0001193125-21-050916 | 10-K | XBRL Viewer

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Cover Page - USD ($) $ in Billions	12 Months Ended
Cover Page - USD ($) $ in Billions	Dec. 31, 2020	Jan. 29, 2021	Jun. 30, 2020
Cover [Abstract]
Amendment Flag	false
Document Fiscal Year Focus	2020
Document Type	10-K
Document Fiscal Period Focus	FY
Entity Central Index Key	0001069878
Current Fiscal Year End Date	--12-31
Document Transition Report	false
Entity Registrant Name	TREX CO INC
Document Period End Date	Dec. 31, 2020
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Trading Symbol	TREX
Entity Shell Company	false
Entity Filer Category	Large Accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
Entity Common Stock, Shares Outstanding		115,799,503
Entity File Number	001-14649
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	54-1910453
Entity Address, Address Line One	160 Exeter Drive
Entity Address, City or Town	Winchester
Entity Address, Postal Zip Code	22603-8605
Entity Address, State or Province	VA
City Area Code	540
Local Phone Number	542-6300
Title of 12(b) Security	Common stock
Security Exchange Name	NYSE
Document Annual Report	true
Entity Well-known Seasoned Issuer	No
Entity Voluntary Filers	No
Entity Public Float			$ 7.5
ICFR Auditor Attestation Flag	true

Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Income Statement [Abstract]
Net sales	$ 880,831	$ 745,347	$ 684,250
Cost of sales	521,374	438,844	389,356
Gross profit	359,457	306,503	294,894
Selling, general and administrative expenses	125,822	118,304	118,225
Income from operations	233,635	188,199	176,669
Interest (income) expense, net	(999)	(1,503)	(192)
Income before income taxes	234,634	189,702	176,861
Provision for income taxes	59,003	44,964	42,289
Net income	$ 175,631	$ 144,738	$ 134,572
Basic earnings per common share	$ 1.52	$ 1.24	$ 1.15
Basic weighted average common shares outstanding	115,888,859	116,861,194	117,479,340
Diluted earnings per common share	$ 1.51	$ 1.24	$ 1.14
Diluted weighted average common shares outstanding	116,252,866	117,315,498	118,134,604
Comprehensive income	$ 175,631	$ 144,738	$ 134,572

Consolidated Balance Sheets - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Current Assets:
Cash and cash equivalents	$ 121,701	$ 148,833
Accounts receivable, net	106,748	78,462
Inventories	68,238	56,106
Prepaid expenses and other assets	25,310	19,803
Total current assets	321,997	303,204
Property, plant and equipment, net	336,537	171,300
Goodwill and other intangible assets, net	73,665	74,084
Operating lease assets	34,382	40,049
Other assets	3,911	3,602
Total Assets	770,492	592,239
Current Liabilities:
Accounts payable	38,622	15,227
Accrued expenses and other liabilities	62,331	58,265
Accrued warranty	5,400	5,178
Total current liabilities	106,353	78,670
Operating lease liabilities	28,579	34,242
Non-current accrued warranty	24,073	20,317
Deferred income taxes	22,956	9,831
Other long-term liabilities		4
Total Liabilities	181,961	143,064
Commitments and contingencies
Stockholders' Equity:
Preferred stock, $0.01 par value, 3,000,000 shares authorized; none issued and outstanding
Common stock, $0.01 par value, 180,000,000 shares authorized; 140,577,005 and 140,374,926 shares issued and 115,799,503 and 116,481,442 shares outstanding at December 31, 2020 and 2019, respectively	1,406	1,404
Additional paid-in capital	126,087	123,294
Retained earnings	737,311	561,680
Treasury stock, at cost, 24,777,502 and 23,893,484 shares at December 31, 2020 and 2019, respectively	(276,273)	(237,203)
Total Stockholders' Equity	588,531	449,175
Total Liabilities and Stockholders' Equity	$ 770,492	$ 592,239

Consolidated Balance Sheets (Parenthetical) - $ / shares	Dec. 31, 2020	Dec. 31, 2019
Statement of Financial Position [Abstract]
Preferred stock, par value	$ 0.01	$ 0.01
Preferred stock, shares authorized	3,000,000	3,000,000
Preferred stock, shares issued	0	0
Preferred stock, shares outstanding	0	0
Common stock, par value	$ 0.01	$ 0.01
Common stock, shares authorized	180,000,000	180,000,000
Common stock, shares issued	140,577,005	140,374,926
Common stock, shares outstanding	115,799,503	116,481,442
Treasury stock, shares	24,777,502	23,893,484

Statements of Changes in Stockholders' Equity - USD ($) $ in Thousands	Total	Common Stock [Member]	Additional Paid-In Capital [Member]	Retained Earnings (Deficit) [Member]	Treasury Stock [Member]
Beginning Balance at Dec. 31, 2017	$ 231,250	$ 1,396	$ 120,996	$ 282,370	$ (173,512)
Beginning Balance, Shares at Dec. 31, 2017		117,713,720			21,974,724
Net income	134,572			134,572
Employee stock plans	882	$ 2	880
Employee stock plans, Shares		126,896
Shares withheld for taxes on awards	(4,695)		(4,695)
Shares withheld for taxes on awards, Shares		(26,056)
Stock-based compensation	6,345	$ 2	6,343
Stock-based compensation, Shares		207,388
Repurchases of common stock	(25,391)				$ (25,391)
Repurchases of common stock, Shares		(918,642)			918,642
Ending Balance at Dec. 31, 2018	342,963	$ 1,400	123,524	416,942	$ (198,903)
Ending Balance, Shares at Dec. 31, 2018		117,103,306			22,893,366
Net income	144,738			144,738
Employee stock plans	1,089	$ 2	1,087
Employee stock plans, Shares		154,282
Shares withheld for taxes on awards	(8,245)		(8,245)
Shares withheld for taxes on awards, Shares		(216,756)
Stock-based compensation	6,930	$ 2	6,928
Stock-based compensation, Shares		440,728
Repurchases of common stock	(38,300)				$ (38,300)
Repurchases of common stock, Shares		(1,000,118)			1,000,118
Ending Balance at Dec. 31, 2019	449,175	$ 1,404	123,294	561,680	$ (237,203)
Ending Balance, Shares at Dec. 31, 2019		116,481,442			23,893,484
Net income	175,631			175,631
Employee stock plans	1,446		1,446
Employee stock plans, Shares		68,061
Shares withheld for taxes on awards	(5,784)		(5,784)
Shares withheld for taxes on awards, Shares		(111,433)
Stock-based compensation	7,133	$ 2	7,131
Stock-based compensation, Shares		245,451
Repurchases of common stock	(39,070)				$ (39,070)
Repurchases of common stock, Shares		(884,018)			884,018
Ending Balance at Dec. 31, 2020	$ 588,531	$ 1,406	$ 126,087	$ 737,311	$ (276,273)
Ending Balance, Shares at Dec. 31, 2020		115,799,503			24,777,502

Consolidated Statements of Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Operating Activities
Net income	$ 175,631	$ 144,738	$ 134,572
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	17,939	14,031	16,597
Deferred income taxes	13,125	7,706	1,037
Stock-based compensation	7,131	6,930	6,344
(Gain) loss on disposal of property, plant and equipment	(56)	285	47
Other non-cash adjustments	51	(218)	(406)
Changes in operating assets and liabilities:
Accounts receivable	(28,286)	12,701	(24,281)
Inventories	(12,132)	1,695	(23,276)
Prepaid expenses and other assets	(358)	(1,652)	(613)
Accounts payable	11,353	(16,666)	21,131
Accrued expenses and other liabilities	7,655	(10,823)	5,040
Income taxes receivable/payable	(4,759)	(2,375)	1,929
Net cash provided by operating activities	187,294	156,352	138,121
Investing Activities
Expenditures for property, plant and equipment and intangibles	(172,823)	(67,265)	(33,816)
Proceeds from sales of property, plant and equipment	2,165	21	83
Net cash used in investing activities	(170,658)	(67,244)	(33,733)
Financing Activities
Borrowings under line of credit	276,000	89,500	172,250
Principal payments under line of credit	(276,000)	(89,500)	(172,250)
Repurchases of common stock	(44,854)	(46,545)	(30,085)
Proceeds from employee stock purchase and option plans	1,446	1,089	882
Financing costs	(360)	(518)
Net cash used in financing activities	(43,768)	(45,974)	(29,203)
Net (decrease) increase in cash and cash equivalents	(27,132)	43,134	75,185
Cash and cash equivalents, beginning of period	148,833	105,699	30,514
Cash and cash equivalents, end of period	121,701	148,833	105,699
Supplemental Disclosure:
Cash paid for interest	187	321	662
Cash paid for income taxes, net	$ 50,744	$ 39,612	$ 48,238

Business and Organization

12 Months Ended

Dec. 31, 2020

Organization, Consolidation and Presentation of Financial Statements [Abstract]

Business and Organization

1.	BUSINESS AND ORGANIZATION

Trex Company, Inc. (together with its wholly-owned subsidiary, the Company), a Delaware corporation, was incorporated on September 4, 1998. The Company operates in two reportable segments, Trex Residential Products (Trex Residential) and Trex Commercial Products (Trex Commercial). The Company’s principal business based on net sales is the manufacture and distribution of Trex Residential wood and plastic composite products, as well as related accessories, primarily for residential decking and railing applications. Trex Commercial designs, engineers and markets modular and architectural railing and staging systems for the commercial and multi-family market, including sports stadiums and performing arts venues. The principal executive offices are located at 160 Exeter Drive, Winchester, Virginia 22603, and the telephone number at that address is

(540) 542-6300.

Summary of Significant Accounting Policies

12 Months Ended

Dec. 31, 2020

Accounting Policies [Abstract]

Summary of Significant Accounting Policies

2.	SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES

Basis of Accounting

The accompanying consolidated financial statements have been prepared in accordance with accounting principles generally accepted in the United States. The consolidated financial statements include the accounts of the Company and its wholly-owned subsidiary, Trex Commercial Products, Inc. Intercompany accounts and transactions have been eliminated in consolidation.

Use of Estimates

The preparation of financial statements in conformity with accounting principles generally accepted in the United States requires management to make estimates and assumptions that affect the amounts reported in the consolidated financial statements and the accompanying notes. Actual results could differ from those estimates.

Cash and Cash Equivalents

Cash equivalents consist of highly liquid investments purchased with original maturities of

three months or less.

Concentrations and Credit Risk

The Company’s financial instruments that are exposed to concentrations of credit risk consist primarily of cash and cash equivalents and trade accounts receivable. The Company from time to time may have bank deposits in excess of insurance limits of the Federal Deposit Insurance Corporation. As of December 31, 2020, substantially all deposits are maintained in one financial institution. The Company has not experienced any losses in such accounts and believes it is not exposed to any significant credit risk related to its cash and cash equivalents.

The Company routinely assesses the financial strength of its customers and believes that its trade receivables credit risk exposure is limited. Trade receivables are recognized at the amount of revenue recognized on each shipment for Trex Residential products and for satisfied performance obligations for Trex Commercial products as the Company has an unconditional right to consideration from the customer and payment is due based solely on the passage of time. An estimate of expected credit losses is recognized as a valuation allowance and adjusted each reporting period. The estimate is based on the current expected credit loss model and is determined using an aging schedule, including past events, current conditions and reasonable and supportable forecasts about the future. There was no material valuation allowance recorded as of December 31, 2020 and December 31, 2019.

In the years ended December 31, 2020, 2019, and 2018 sales to certain customers of Trex Residential accounted for 10% or more of the Company’s total net sales. For the year ended December 31, 2020, three customers represented approximately 56% of the Company’s total net sales. For the year ended December 31, 2019,

three customers of Trex Residential represented approximately 57% of the Company’s total net sales. For the year ended December 31, 2018,

two customers of Trex Residential represented approximately 42% of the Company’s total net sales. At December 31, 2020 two customers represented 27% and 15%, respectively, of the Company’s accounts receivable balance. At December 31, 2019 three customers represented 30%, 24% and 10%, respectively, of the Company’s total accounts receivable balance.

For each year ended December 31, 2020, 2019, and 2018, approximately 28%, 27%, and 33%, respectively, of the Company’s materials purchases at Trex Residential were purchased from its

four largest suppliers.

Inventories

Inventories for the Company’s composite decking and railing products are valued at the lower of cost

(last-in,

first-out,

or LIFO, method) and market as this method results in a better matching of costs and revenues. The Company periodically reviews its inventory for slow moving or obsolete items and writes down the related products to estimated realizable value. The Company’s reserves for estimated slow moving products or obsolescence are not material. At December 31, 2020, the excess of the replacement cost of inventory over the LIFO value of inventory was approximately $16.8 million. Due to the nature of the LIFO valuation methodology, liquidations of inventories will result in a portion of the Company’s cost of sales being based on historical rather than current year costs.

A majority of the Company’s products at Trex Residential are made in a proprietary process that combines reclaimed wood fibers and scrap polyethylene. The Company grinds up scrap materials generated from its manufacturing process and inventories deemed no longer salable and reintroduces the reclaimed material into the manufacturing process as a substitute for raw materials. The reclaimed material is valued at the costs of the raw material components of the material.

Inventories for the Company’s railing and staging products at Trex Commercial for the commercial and multi-family market are valued at the lower of cost

(first-in,

first-out

or FIFO method), using actual cost, and net realizable value.

Work-in

process includes estimated production costs.

Property, Plant and Equipment

Property, plant and equipment are stated at historical cost. The costs of additions and improvements are capitalized, while maintenance and repairs are expensed as incurred. Unpaid liabilities related to property, plant and equipment are included in accounts payable and were $12.9 million and $0.8 million at December 31, 2020 and December 31, 2019, respectively. Cash flows for capital expenditures as reported in cash flows from investing activities in the Consolidated Statements of Cash Flows are adjusted to exclude unpaid amounts accrued at period end. Depreciation is provided using the straight-line method over the following estimated useful lives:


Buildings		40 years
Machinery and equipment		3-11 years
Furniture and equipment		10 years
Forklifts and tractors		5 years
Computer equipment and software		5 years

Leasehold improvements are amortized over the shorter of the lease term or the estimated useful life of the asset.

The Company reviews its long-lived assets, including property, plant and equipment, whenever events or changes in circumstances indicate that the carrying amount of the assets may not be fully recoverable. To determine the recoverability of its long-lived assets, the Company evaluates the probability that future estimated undiscounted net cash flows will be less than the carrying amount of the long-lived assets. If the estimated cash flows are less than the carrying amount of the long-lived assets, the assets are written down to their fair value. The Company’s estimates of anticipated cash flows and the remaining estimated useful lives of long-lived assets could be reduced in the future. As a result, the carrying amount of long-lived assets could be reduced in the future. Long-lived

assets

held for sale are stated at the lower of cost or fair value less cost to sell.

Leases

The Company leases office space, storage warehouses and certain plant equipment under various operating leases. At inception of an arrangement, the Company evaluates, among other things, whether it has the right to control the use of an identified asset in order to determine if the arrangement is or contains a lease. Operating leases are included in operating lease

right-of-use

(ROU) assets, accrued expenses and other current liabilities, and operating lease liabilities in the consolidated balance sheets. Operating leases with an initial term of 12 months or less are not included in the consolidated balance sheet. The Company recognizes lease expense for these leases on a straight-line basis over the lease term. ROU assets represent the right to use an underlying asset for the lease term and operating lease liabilities represent the obligation to make lease payments arising from the lease. Operating lease ROU assets and liabilities are recognized at commencement date based on the present value of lease payments over the lease term. As the Company’s leases do not provide an implicit rate, the Company uses its incremental borrowing rate based on the information available at the commencement date in determining the present value of lease payments. The Company gives consideration to instruments with similar characteristics when calculating its incremental borrowing rate. Certain events, such as a modification to the arrangement or a change in the lease term, are assessed by the Company to determine if it is required to reassess estimates and judgments and remeasure the lease liability and ROU asset. The Company reviews its ROU asset for impairment whenever events or changes in circumstances indicate that the carrying amount of the asset may not be fully recoverable. The carrying amount of the ROU asset is not recoverable if it exceeds the sum of the undiscounted cash flows expected to result from the use of the asset. An impairment loss is measured as the amount by which the carrying amount of the ROU asset exceeds its fair value. The Company’s operating leases have remaining lease terms of 1 year to 8 years. Lease terms may include options to extend or terminate the lease when the Company determines that it is reasonably certain it will exercise the option. Lease expense for operating lease payments is recognized on a straight-line basis over the lease term. The Company has lease agreements with lease and

non-lease

components, which are accounted for separately. Consideration for

non-lease

components is stated on a stand-alone basis in the applicable agreements.

Fair Value Measurement

Assets and liabilities measured at fair value are measured at the amount that would be received for selling an asset or paid to transfer a liability in an orderly transaction between market participants at the measurement date and classified into one of the following fair value hierarchy:

•

Level 1 – Quoted prices for identical instruments in active markets.

•

Level 2 – Quoted prices for similar instruments in active markets; quoted prices for identical or similar instruments in markets that are not active; and model derived valuations in which all significant inputs and significant value drivers are observable in active markets.

•

Level 3 – Valuations derived from management’s best estimate of what market participants would use in pricing the asset or liability at the measurement date. Consideration is given to the risk inherent in the valuation technique and the risk inherent in the inputs to the model.

Goodwill

Goodwill represents the excess of cost over net assets acquired resulting from the Company’s 1996 purchase of the Mobil Composite Products Division, the 2011 purchase of the assets of the Iron Deck Corporation, and the 2017 purchase of certain assets and the assumption of certain liabilities of SC Company. The Company evaluates the recoverability of goodwill in accordance with Accounting Standard Codification Topic 350, “

Intangibles – Goodwill and Other

,” annually or more frequently if an event occurs or circumstances change in the interim that would more likely than not reduce the fair value of the asset below its carrying amount. Goodwill is considered to be impaired when the net book value of the reporting unit exceeds its estimated fair value.

The Company assigned its goodwill to reporting units and tests each reporting unit’s goodwill for impairment at least on an annual basis, or more frequently if an event occurs or circumstances change in the interim that indicate the carrying amount of reporting unit goodwill exceeds the implied fair value of that goodwill. The Company identified its reporting units based on the way it manages its operating segments. Each reporting unit constitutes a business with discrete financial information and operating segment management, at a level below the Company’s chief operating decision maker, regularly reviews the operating results of the reporting unit. The Company assigned goodwill to the reporting units based on the excess of the fair values acquired over the fair value of the sum of the individual assets acquired and liabilities assumed that were assigned to the reporting units.

In testing for goodwill impairment, the Company first assesses qualitative factors to determine whether it is more likely than not that the fair value of a reporting unit is less than its carrying amount, including goodwill. If the qualitative assessment indicates that the carrying amount of the reporting unit exceeds its fair value, including goodwill, the Company is then required to perform a quantitative goodwill impairment test. The quantitative goodwill impairment test, used to identify both the existence of impairment and the amount of impairment loss, compares the fair value of a reporting unit with its carrying amount, including goodwill. The fair value of a reporting unit refers to the price that would be received to sell the unit as a whole in an orderly transaction between market participants at the measurement date. If the carrying amount of a reporting unit exceeds its fair value, an impairment loss is recognized in an amount equal to that excess, limited to the total amount of goodwill allocated to that reporting unit.

The Company measures fair value of the reporting units based on a present value of future cash flows (discounted cash flows model) and a market valuation approach. The discounted cash flows model indicates the fair value of the reporting unit based on the present value of the cash flows that the reporting unit is expected to generate in the future. Significant estimates in the discounted cash flows model include: the weighted average cost of capital; long-term rate of growth and profitability of the business; and working capital effects. The market valuation approach indicates the fair value of the business based on a comparison of the Company against certain market information. Significant estimates in the market approach model include identifying appropriate market multiples and assessing earnings before interest, income taxes, depreciation and amortization (EBITDA) in estimating the fair value of the reporting unit.

For the years ended December 31, 2020, 2019, and 2018, the Company completed its annual impairment test of goodwill utilizing the qualitative assessment and concluded it was not more likely than

not that the fair value of the reporting units was less than the carrying amounts. The Company performs the annual impairment testing of its goodwill as of October 31 of each year. However, actual results could differ from the Company’s estimates and projections, which would affect the assessment of impairment. As of December 31, 2020, the Company had goodwill of $68.5 million that is reviewed annually for impairment.

Product Warranty

The Company warrants that its Trex Residential decking products will be free from material defects in workmanship and materials. This warranty generally extends for a period of 25 years for residential use and

10 years for commercial use. With respect to Trex Signature

Railing, the warranty period is 25 years for both residential and commercial use. With respect to the Company’s Transcend

, Enhance

, Select

and Universal Fascia product, the Company further warrants that the product will not fade in color more than a certain amount and will be resistant to permanent staining from food substances or mold, provided the stain is cleaned within seven days of appearance. This warranty extends for a period of

years for residential use and 10 years for commercial use. If there is a breach of such warranties, the Company has an obligation either to replace the defective product or refund the purchase price. Depending on the product and its use, the Company also warrants its Trex Commercial products will be free of manufacturing defects for one to three years. The Company establishes warranty reserves to provide for estimated future expenses as a result of product defects that result in claims. Reserve estimates are based on management’s judgment, considering such factors as cost per claim, historical experience, anticipated rates of claims, and other

available

information. Management reviews and adjusts these estimates, if necessary, based on the differences between

actual

experience and historical estimates.

Treasury Stock

The Company records the repurchase of shares of its common stock at cost. These shares are considered treasury stock, which is a reduction to stockholders’ equity. Treasury stock is included in authorized and issued shares but excluded from outstanding shares.

Revenue Recognition

Effective January 1, 2018, the Company retrospectively adopted the requirements of Financial Accounting Standards Board (FASB) Accounting Standards Update (ASU)

2014-09,

“Revenue from Contracts with Customers” (Topic 606). The Company determined the appropriate revenue recognition for its contracts with customers by analyzing the type, terms and conditions of the contracts with customers. Topic 606 provides a single, comprehensive model for revenue recognition arising from contracts with customers. A performance obligation is a promise in a contract to transfer a distinct good or service to the customer and is the unit of account in Topic 606. A contract’s transaction price is allocated to each distinct performance obligation and revenue is recognized when or as the Company satisfies the performance obligation. Revenue is recognized at an amount that reflects the consideration to which the entity expects to be entitled in exchange for transferring control of the goods or services to a customer. Adoption of Topic 606 did not have an impact on the Company’s financial condition or results of operations. The following provides additional information about the Company’s contracts with customers.

Trex Residential Products.

Trex Residential principally generates revenue from the manufacture and sale of its high-performance,

low-maintenance,

eco-friendly

composite decking and railing products and accessories. Substantially all of its revenues are from contracts with customers, which are individual customer purchase orders of short-term duration of less than one year. Trex Residential satisfies its performance obligations at a point in time. The shipment of each product is a separate performance obligation as the customer is able to derive benefit from each product shipped and no performance obligation remains after shipment. Upon shipment of the product, the customer obtains control over the distinct product and Trex Residential satisfies its performance obligation. Any performance obligation that remains unsatisfied at the end of a reporting period is part of a contract that has an original expected duration of one year or less. Any variable consideration related to the unsatisfied performance obligation is allocated wholly to the unsatisfied performance obligation and recognized when the product ships and the performance obligation is satisfied.

Trex Commercial Products.

Trex Commercial generates revenue from the manufacture and sale of its modular and architectural railing and staging systems. All of its revenues are from fixed-price contracts with customers. Trex Commercial contracts have a single performance obligation as the promise to transfer the individual goods or services is not separately identifiable from other promises in the contract and is, therefore, not distinct.

Trex Commercial satisfies its performance obligation over

time

as work progresses because control is transferred continuously to its customers. Revenue and estimated profit are recognized over time based on the proportion of actual costs incurred to date relative to total estimated costs at completion to measure progress toward satisfying the performance obligation. Incurred costs represent work performed, which corresponds with, and thereby best depicts, the transfer of control to the customer. Incurred costs include all direct material, labor, subcontract and certain indirect costs. The Company reviews and updates its estimates regularly and recognizes adjustments in estimated profit on contracts under the cumulative

catch-up

Stock-Based Compensation

The Company measures stock-based compensation at the grant date of the award based on the fair value. For stock options, stock appreciation rights and time-based restricted stock and time-based restricted stock units, stock-based compensation is recognized on a straight-line basis over the vesting periods of the award. The Company recognizes forfeitures as they occur. For performance-based restricted stock and performance-based restricted stock units, expense is recognized ratably over the performance and vesting period of each tranche based on management’s judgment of the ultimate award that is probable to be paid out based on the achievement of predetermined performance measures. Stock-based compensation expense is included in “Selling, general and administrative expenses” in the accompanying Consolidated Statements of Comprehensive Income.

Income Taxes

The Company recognizes deferred tax assets and liabilities based on the difference between the financial statement basis and tax basis of assets and liabilities using enacted rates expected to be in effect during the year in which the differences reverse. The Company assesses the likelihood that its deferred tax assets will be realized. Deferred tax assets are reduced by a valuation allowance when, after considering all available positive and negative evidence, it is determined that it is more likely than not that some portion, or all, of the deferred tax asset will not be realized. As of December 31, 2020, the Company has a valuation allowance of $2.8 million against these deferred tax assets. The Company analyzes its position in subsequent reporting periods, considering all available positive and negative evidence, in determining the expected realization of its deferred tax assets.

Research and Development Costs

Research and development costs are expensed as incurred. For the years ended December 31, 2020, 2019, and 2018, research and development costs were $3.4 million, $4.5 million, and $4.2 million, respectively, and have been included in “Selling, general and administrative expenses” in the accompanying Consolidated Statements of Comprehensive Income.

Advertising Costs

The Company expenses its branding and advertising communication costs as incurred. Production costs are deferred and recognized as expense in the period that the related advertisement is first used. At December 31, 2020 and December 31, 2019 $0.01 million and $0.5 million was included in prepaid expenses for production costs, respectively.

For the years ended December 31, 2020, 2019, and 2018, branding expenses, including advertising expenses as described above, were $31.7 million, $35.7 million, and $35.0 million, respectively.

Fair Value of Financial Instruments

The Company considers the recorded value of its financial assets and liabilities, consisting primarily of cash and cash equivalents, accounts receivable, accounts payable, accrued expenses and other current liabilities, and debt to approximate the fair value of the respective assets and liabilities on the Consolidated Balance Sheets at December 31, 2020 and 2019.

Recently Adopted Accounting Standards

In August 2018, the Financial Accounting Standards Board (FASB) issued Accounting Standards Update (ASU)

No. 2018-15,

“

Intangibles – Goodwill and Other –

Internal-Use

Software (Subtopic

350-40):

Customer’s Accounting for Implementation Costs Incurred in a Cloud Computing Arrangement That Is a Service Contract (a consensus of FASB Emerging Issues Task Force)

”. The new guidance aligns the requirements for capitalizing implementation costs in a cloud computing arrangement service contract with the requirements for capitalizing implementation costs incurred for an

internal-use

software license. Under that model, implementation costs are capitalized or expensed depending on the nature of the costs and the project stage during which they are incurred. Capitalized implementation costs are amortized over the term of the associated hosted cloud computing arrangement service contract on a straight-line basis, unless another systematic and rational basis is more representative of the pattern in which the entity expects to benefit from its right to access the hosted software. Capitalized implementation costs would then be assessed for impairment in a manner similar to long-lived assets. The new guidance was effective for fiscal years beginning after December 15, 2019, and interim periods within those fiscal years. Entities can adopt the new guidance either prospectively to eligible costs incurred on or after the date the guidance is first applied or retrospectively. The Company adopted the guidance prospectively on January 1, 2020. Adoption did not have a material impact on its consolidated financial condition or results of operations.

In January 2017, the FASB issued ASU

No. 2017-04,

“

Intangibles—Goodwill and Other (Topic 350), Simplifying the Test for Goodwill Impairment

”. The guidance removes Step 2 of the goodwill impairment test and eliminates the need to determine the fair value of individual assets and liabilities to measure goodwill impairment. A goodwill impairment will now be the amount by which a reporting unit’s carrying value exceeds its fair value, not to exceed the carrying amount of goodwill. Entities will continue to have the option to perform a qualitative assessment to determine if a quantitative impairment test is necessary. The guidance was applied prospectively and was effective for annual and interim goodwill impairment tests in fiscal years beginning after December 15, 2019. The Company adopted the guidance on January 1, 2020. Adoption did not have a material impact on its consolidated financial condition or results of operations.

In June 2016, the FASB issued ASU

2016-13,

“

Financial Instruments – Credit Losses (Topic 326): Measurement of Credit Losses in Financial Instruments

,” as amended. The ASU amends the guidance on the impairment of financial instruments and adds an impairment model, known as the current expected credit loss (CECL) model. The CECL model requires an entity to recognize its current estimate of all expected credit losses, rather than incurred losses, and applies to trade receivables and other receivables. The CECL model is designed to capture expected credit losses through the establishment of an allowance account, which will be presented as an offset to the amortized cost basis of the related financial asset. The new guidance was effective for fiscal years beginning after December 15, 2019, including interim periods within those fiscal years, and is applied using the modified-retrospective approach. The Company adopted the guidance on January 1, 2020. Adoption did not have a material impact on its consolidated financial condition or results of operations.

New Accounting Standards Not Yet Adopted

In March 2020, the FASB issued ASU

No. 2020-04,

“

Reference Rate Reform (Topic 848): Facilitation of the Effects of Reference Rate Reform on Financial Reporting

”. The guidance provides temporary optional expedients and exceptions related to contract modifications and hedge accounting to ease entities’ financial

reporting burdens as the market transitions from the London Interbank Offered Rate and other interbank offered rates to alternative reference rates. The new guidance allows entities to elect not to apply certain modification accounting requirements, if certain criteria are met, to contracts affected by what the guidance calls reference rate reform. An entity that makes this election would consider changes in reference rates and other contract modifications related to reference rate reform to be events that do not require contract remeasurement at the modification date or reassessment of a previous accounting determination. The ASU notes that changes in contract terms that are made to affect the reference rate reform transition are considered related to the replacement of a reference rate if they are not the result of a business decision that is separate from or in addition to changes to the terms of a contract to affect that transition. The guidance is effective upon issuance and generally can be applied as of March 12, 2020 through December 31, 2022. The Company does not expect adoption of the guidance to have a material effect on its consolidated financial statements.

In December 2019, the FASB issued ASU

No. 2019-12,

“

Income Taxes (Topic 740), Simplifying the Accounting for Income Taxes

”. The guidance eliminates certain exceptions related to the approach for intraperiod tax allocation, the methodology for calculating income taxes in an interim period, and the recognition of deferred tax liabilities for outside basis differences related to changes in ownership of equity method investments and foreign subsidiaries. The guidance also simplifies aspects of accounting for franchise taxes and enacted changes in tax laws or rates and clarifies the accounting for transactions that result in a

step-up

in the tax basis of goodwill. The standard will be effective for fiscal years, and interim periods within those fiscal years, beginning after December 15, 2020, with early adoption permitted. The Company does not intend to early adopt the standard and does not expect the standard to have a material effect on its consolidated financial statements.

Inventories

12 Months Ended

Dec. 31, 2020

Inventory Disclosure [Abstract]

Inventories

3.	INVENTORIES

Inventories at LIFO value consist of the following as of December 31 (in thousands):


	2020			2019
Finished goods	$	39,048		$	42,281
Raw materials		44,475			31,686

Total FIFO inventories		83,523			73,967
Reserve to adjust inventories to LIFO value		(16,821	)		(19,062	)

Total LIFO inventories	$	66,702		$	54,905

Inventory related to Trex Residential composite decking and railing products is stated at the lower of LIFO cost or market. The Company periodically reviews its inventory for slow moving or obsolete items and writes down the related products to estimated market.

Under the LIFO method, reductions in inventory cause a portion of the Company’s cost of sales to be based on historical costs rather than current year costs. There was

no material inventory reduction during 2020 or 2019.

Inventories valued at lower of cost (FIFO method) and net realizable value as of December 31, 2020 and December 31, 2019, were $1.5 million and $1.2 million, respectively, consisting primarily of raw materials. The Company utilizes the FIFO method of accounting related to its Trex Commercial products.

Prepaid Expenses and Other Assets

12 Months Ended

Dec. 31, 2020

Text Block [Abstract]

Prepaid Expenses and Other Assets

4.	PREPAID EXPENSES AND OTHER ASSETS

Prepaid expenses and other assets consist of the following as of December 31 (in thousands):


	2020		2019
Prepaid expenses	$	7,285	$	8,282
Revenues in excess of billings		6,612		6,664
Contract retainage		2,267		1,832
Income tax receivable		7,823		2,675
Other		1,323		350

Total prepaid expenses and other assets	$	25,310	$	19,803

Goodwill and Other Intangible Assets, Net

12 Months Ended

Dec. 31, 2020

Goodwill and Intangible Assets Disclosure [Abstract]

Goodwill and Other Intangible Assets, Net

5.	GOODWILL AND OTHER INTANGIBLE ASSETS, NET

The carrying amount of goodwill by reportable segment at December 31, 2020 and 2019 was $14.2 million for Trex Residential and $54.3 million for Trex Commercial.

The Company’s intangible assets consist of domain names purchased in May 2018. At December 31, 2020 and 2019, intangible assets were $6.3 million, and accumulated amortization was $1.1 million and $0.7 million, respectively. Intangible asset amounts were determined based on the estimated economics of the asset and are amortized over the estimated useful lives on a straight-line basis over 15 years, which approximates the pattern in which the economic benefits are expected to be received. The Company evaluates the recoverability of intangible assets periodically and considers events or circumstances that may warrant revised estimates of useful lives or that may indicate an impairment. Intangible asset amortization expense for the years ended December 31, 2020, December 31, 2019 and December 31, 2018, was $0.4 million, $0.4 million and $3.1 million, respectively. Intangible asset amortization expense for the year ended December 31, 2018 included amortization expense for customer backlog and trade names and trademarks, which were fully amortized as of December 31, 2018.

Property, Plant and Equipment

12 Months Ended

Dec. 31, 2020

Property, Plant and Equipment [Abstract]

Property, Plant and Equipment

6.	PROPERTY, PLANT AND EQUIPMENT

Property, plant and equipment consist of the following as of December 31 (in thousands):


	2020			2019
Machinery and equipment	$	312,870		$	248,633
Building and improvements		61,860			51,547
Forklifts and tractors		16,003			10,870
Computer equipment		11,948			10,647
Furniture and fixtures		1,534			1,441
Construction in process		157,465			59,257
Land		11,351			11,417

Total property, plant and equipment		573,031			393,812
Accumulated depreciation		(236,494	)		(222,512	)

Total property, plant and equipment, net	$	336,537		$	171,300

The Company had construction in process as of December 31, 2020 of approximately $157.5 million. The Company expects that the construction in process will be completed and put into service in the year ending December 31, 2021.

Depreciation expense for the years ended December 31, 2020, 2019, and 2018, totaled $17.5 million, $13.6 million, and $13.4 million, respectively.

Accrued Expenses and Other Liabilities

12 Months Ended

Dec. 31, 2020

Payables and Accruals [Abstract]

Accrued Expenses and Other Liabilities

7.	ACCRUED EXPENSES AND OTHER LIABILITIES

Accrued expenses and other liabilities consist of the following as of December 31 (in thousands):


	2020		2019
Sales and marketing	$	22,938	$	28,402
Compensation and benefits		21,156		13,475
Operating lease liabilities		6,708		7,079
Manufacturing costs		3,641		2,564
Customer deposits		1,174		2,905
Billings in excess of revenues		1,244		816
Other		5,470		3,024

Total accrued expenses	$	62,331	$	58,265

Debt

12 Months Ended

Dec. 31, 2020

Debt Disclosure [Abstract]

Debt

DEBT

The Company’s debt consists of a revolving credit facility. At December 31, 2020 and 2019, the Company had no outstanding indebtedness. Available borrowing capacity at December 31, 2020, was $300 million.

Revolving Credit Facility

On November 5, 2019, the Company entered into a Fourth Amended and Restated Credit Agreement (Fourth Amended Credit Agreement) as borrower, Trex Commercial Products, Inc., as guarantor; Bank of America, N.A. as a Lender, Administrative Agent, Swing Line Lender and L/C Issuer; and certain other lenders including Wells Fargo Bank, N.A., who is also Syndication Agent, and Truist Bank, arranged by BOA Securities, Inc., as Sole Lead Arranger and Sole Bookrunner, to amend and restate the Third Amended and Restated Credit Agreement (Third Amended Credit Agreement), dated as of January 12, 2016, as amended. The Fourth Amended Credit Agreement provides the Company with one or more Revolving Loans in a collective maximum principal amount of $250 million from January 1 through June 30 of each year and a maximum principal amount of $200 million from July 1 through December 31 of each year throughout the term, which ends November 5, 2024.

On May 26, 2020, the Company entered into a First Amendment to the Original Credit Agreement (the First Amendment) to provide for an additional $100 million line of credit through May 26, 2022. The purpose of the additional $100 million line of credit is primarily to reduce risk associated with the

COVID-19

pandemic should the Company need to secure additional capital to continue its strategy of accelerating the conversion of wood decking to Trex composite decking and expanding its addressable market. As a matter of convenience, the parties incorporated the amendments to the Original Credit Agreement made by the First Amendment into a new Fourth Amended and Restated Credit Agreement (New Credit Agreement). In the New Credit Agreement, the revolving commitments under the Original Credit Agreement are referred to as Revolving A Commitments and the new $100 million line of credit is referred to as Revolving B Commitments. In the New Credit Agreement, all of the material terms and conditions related to the original line of credit (Revolving A Commitments) remain unchanged from the Original Credit Agreement.

The Company entered into the First Amendment, as borrower; Trex Commercial Products, Inc. (TCP), as guarantor; Bank of America, N.A. (BOA), as a Lender, Administrative Agent, Swing Line Lender and L/C Issuer; and certain other lenders including Wells Fargo Bank, N.A. (Wells Fargo), who is also Syndication Agent; Truist Bank (Truist); and Regions Bank (Regions) (each, a Lender and collectively, the Lenders), arranged by BofA Securities, Inc. as Sole Lead Arranger and Sole Bookrunner. The First Amendment further provides that the New Credit Agreement is amended and restated by changing Schedule 2.01 to add applicable Lender percentages related to the Revolving B Commitment for BOA of 47.5%,

Wells

Fargo of 28.0% and Regions of 24.5%.

The Notes and interest rates for the Revolving A Commitments remained unchanged and are the same as previously disclosed. The Notes for Revolving A Commitments and Revolving B Commitments provide the Company, in the aggregate, the ability to borrow an amount up to the respective Revolving A Loan Limit and Revolving B Loan Limit during the respective Revolving A Term and Revolving B Term. The Company is not obligated to borrow any amount under either the Revolving A Loan or the Revolving B Loan. Within either the Revolving A Loan or the Revolving B Loan, the Company may borrow, repay and reborrow at any time or from time to time while the respective Revolving A Loan or Revolving B Loan remains in effect.

Base Rate Loans (as defined in the Fourth Amended Credit Agreement) under the Revolving Loans and the Swing Line Loans accrue interest at the Base Rate plus the Applicable Rate (as defined in the Fourth Amended Credit Agreement) and Eurodollar Rate Loans for the Revolving Loans and Swing Line Loans accrue interest at the Adjusted London InterBank Offered Rate plus the Applicable Rate (as defined in the Fourth Amended Credit Agreement).

The Base Rate for any day is a fluctuating rate per annum equal to the highest of (a) the Federal Funds Rate plus 0.50%, (b) the rate of interest in effect for such day as publicly announced from time to time by BOA as its prime rate, and (c) the Eurodollar Rate plus 1.0%.

The Applicable Rate for Revolving B Commitments means the following percentages per annum, based upon the Consolidated Debt to Consolidated EBITDA Ratio as set forth in the most recent Compliance Certificate received by BOA as the Administrative Agent and as set forth in the New Credit Agreement:


Pricing Tier	Consolidated Debt to Consolidated EBITDA Ratio	Eurodollar Rate Loans / LIBOR Index Rate			Base Rate Loans			Revolving B Commitment Fee
1	> 2.50:1.00		2.75	%		1.75	%		0.60	%
2	< 2.50:1.00 but > 2.00:1.00		2.50	%		1.50	%		0.55	%
3	< 2.00:1.00 but > 1.50:1.00		2.25	%		1.25	%		0.50	%
4	< 1.50:1.00		1.80	%		0.80	%		0.45	%

Compliance with Debt Covenants and Restrictions

Pursuant to the terms of the Fourth Amended Credit Agreement, the Company is subject to certain loan compliance covenants. The Company was in compliance with all covenants as of December 31, 2020. Failure to comply with the financial covenants could be considered a default of repayment obligations and, among other remedies, could accelerate payment of any amounts outstanding.

Leases

12 Months Ended

Dec. 31, 2020

Leases [Abstract]

Leases

LEASES

For the years ended December 31, 2020 and December 31, 2019, total operating lease cost was $8.5 million and $8.4 million, respectively. The weighted average remaining lease term at December 31, 2020 and December 31, 2019 was 5.6 years and 6.5 years, respectively. The weighted average discount rate at December 31, 2020 and December 31, 2020 was 3.47% and 3.66%, respectively.

The following table includes supplemental cash flow information for the years ended December 31, 2020 and December 31, 2019 and supplemental balance sheet information at December 31, 2020 and December 31, 2019 related to operating leases:


	For the Year Ended December 31
Supplemental Cash Flow Information	2020		2019
Cash paid for amounts included in the measurement of operating lease liabilities	$	8,736	$	8,479
Operating ROU assets obtained in exchange for lease liabilities	$	1,427	$	1,319

Supplemental Balance Sheet Information	December 31, 2020		December 31, 2019
Operating lease ROU assets	$	34,382	$	40,049
Operating lease liabilities:
Accrued expenses and other current liabilities	$	6,708	$	7,079
Operating lease liabilities		28,579		34,242

Total operating lease liabilities	$	35,287	$	41,321

The following table summarizes maturities of operating lease liabilities at December 31, 2020 (in thousands):


Maturities of operating lease liabilities
2021	$	7,835
2022		7,345
2023		6,608
2024		6,265
2025		4,480
Thereafter		6,599

Total lease payments		39,132
Less imputed interest		(3,845	)

Total operating liabilities	$	35,287

Financial Instruments

12 Months Ended

Dec. 31, 2020

Investments, All Other Investments [Abstract]

Financial Instruments

10.	FINANCIAL INSTRUMENTS

Stockholders' Equity

12 Months Ended

Dec. 31, 2020

Equity [Abstract]

Stockholders' Equity

11.	STOCKHOLDERS’ EQUITY

Earnings Per Share

The following table sets forth the computation of basic and diluted earnings per share (in thousands, except share and per share data):


	Year Ended December 31,
	2020		2019		2018
Numerator:
Net income	$	175,631	$	144,738	$	134,572

Denominator:
Basic weighted average shares outstanding		115,888,859		116,861,194		117,479,340
Effect of dilutive securities:
Stock appreciation rights		192,579		248,850		353,400
Restricted stock		171,428		205,454		301,864

Diluted weighted average shares outstanding		116,252,866		117,315,498		118,134,604

Basic earnings per share	$	1.52	$	1.24	$	1.15

Diluted earnings per share	$	1.51	$	1.24	$	1.14

Diluted earnings per share is computed using the weighted average number of shares determined for the basic earnings per share computation plus the dilutive effect of common stock equivalents using the treasury stock method.

The computation of diluted earnings per share excludes the following potentially dilutive securities because the effect would be anti-dilutive:


	Year Ended December 31,
	2020		2019		2018
Restricted stock		—		—		428
Stock appreciation rights		14,697		41,540		26,694

Stock Repurchase Program

On February 16, 2018, the Board of Directors adopted a stock repurchase program of up to 11.6 million shares of the Company’s outstanding common stock (Stock Repurchase Program). On March 12, 2020, the Company suspended repurchases of its common stock under the Stock Repurchase Program due to the volatility and uncertainty in the stock market associated with the

COVID-19

pandemic. On October 30, 2020, the Company lifted the suspension of repurchases of its common stock under the Stock Repurchase Program. As of December 31, 2020, the Company has repurchased 2.8 million shares of the Company’s outstanding common stock under the Stock Repurchase Program.

Amendment of Restated Certificate of Incorporation

At the annual meeting of stockholders of the Company held on April 29, 2020, the Company’s stockholders approved an amendment of the Company’s Restated Certificate of Incorporation (Amendment), effective as of April 29, 2020. The Company’s Board of Directors unanimously approved the Amendment on February 19, 2020, subject to stockholder approval. The Amendment increases the number of shares of common stock, par value $0.01 per share, that the Company is authorized to issue from 120 million shares to 180 million shares.

Stock Split

On July 29, 2020, the Company’s Board of Directors approved a

two-for-one

stock split of the Company’s common stock, par value, $0.01. The stock split was in the form of a stock dividend distributed on September 14, 2020, to stockholders of record at the close of business on August 19, 2020. The stock split entitled each stockholder to receive one additional share of common stock for each share they held as of the record date. All common stock share and per share data for all periods presented in the accompanying consolidated financial statements and notes thereto have been retroactively adjusted to reflect the stock split.

Revenue From Contracts With Customers

12 Months Ended

Dec. 31, 2020

Revenue from Contract with Customer [Abstract]

Revenue From Contracts With Customers

12.	REVENUE FROM CONTRACTS WITH CUSTOMERS

Topic 606 provides a single, comprehensive model for revenue recognition arising from contracts with customers. A performance obligation is a promise in a contract to transfer a distinct good or service to the customer and is the unit of account in Topic 606. A contract’s transaction price is allocated to each distinct performance obligation and revenue is recognized when or as the Company satisfies the performance obligation. Revenue is recognized at an amount that reflects the consideration to which the entity expects to be entitled in exchange for transferring control of the goods or services to a customer.

Trex Residential Products

Trex Residential principally generates revenue from the manufacture and sale of its high-performance,

low-maintenance,

eco-friendly

wood-alternative composite decking and residential railing products and accessories. Substantially all of its revenues are from contracts with customers, which are purchase orders of short-term duration of less than one year. Its customers, in turn, sell primarily to the residential market, which includes replacement, remodeling and new construction related to outdoor living products. Trex Residential satisfies its performance obligations at a point in time. The shipment of each product is a separate performance obligation as the customer is able to derive benefit from each product shipped and no performance obligation remains after shipment. Upon shipment of the product, the customer obtains control over the distinct product and Trex Residential satisfies its performance obligation. Any performance obligation that remains unsatisfied at the end of a reporting period is part of a contract that has an original expected duration of one year or less. Any variable consideration related to the unsatisfied performance obligation is allocated wholly to the unsatisfied performance obligation and recognized when the product ships and the performance obligation is satisfied.

For each product shipped, the transaction price by product is specified in the purchase order. The Company recognizes revenue on the transaction price less any amount offered under a sales incentive program. The Company recognizes an account receivable for the amount of revenue recognized as it has an unconditional right to consideration at the time of shipment and payment from the customer is due based solely on the passage of time. The Company receives payments from its customers based on the payment terms applicable to each individual contract and the customer pays in accordance with the billing terms specified in the purchase order, which is less than one year. The related accounts receivables are included in “Accounts receivable, net” in the Consolidated Balance Sheets.

Trex Residential may offer various sales incentive programs throughout the year. It estimates the amount of sales incentive to allocate to each performance obligation, or product shipped, based on direct sales to the customer. The estimate is updated each reporting period and any changes are allocated to the performance obligations on the same basis as at inception. Changes in estimate allocated to a previously satisfied performance obligation are recognized as a reduction of revenue in the period in which the change occurs under the cumulative

catch-up

method. In addition to sales incentive programs, Trex Residential may offer payment discounts. It estimates the payment discount that it believes will be taken by the customer based on prior history using the most-likely-amount method of estimation.

Trex Residential pays commissions to certain employees. However, the sales commissions are not directly attributable to identifiable contracts, are discretionary in nature and are based on other factors not related to obtaining a contract, such as individual performance, profitability of the entity, annual sales targets, etc. These costs are included in selling, general and administrative expenses as incurred. Trex Residential does not grant contractual product return rights to customers other than pursuant to its assurance product warranty (see related disclosure on product warranties in Note 18, “Commitments and Contingencies”. Trex Residential accounts for all shipping and handling fees invoiced to the customer in net sales and the related costs in cost of sales.

Trex Commercial Products

Trex Commercial satisfies its performance obligation over time as work progresses because control is transferred continuously to its customers. Revenue and estimated profit is recognized over time based on the proportion of actual costs incurred to date relative to total estimated costs at completion to measure progress toward satisfying the performance obligation. Incurred costs represent work performed, which corresponds with, and thereby best depicts, the transfer of control to the customer. Incurred costs include all direct material, labor, subcontract and certain indirect costs. The Company reviews and updates its estimates regularly and recognizes adjustments in estimated profit on contracts under the cumulative

catch-up

method. Under this method, the impact of the adjustment on revenue and estimated profit to date on a contract is recognized in the period the adjustment is identified. Revenues and profits in future periods are recognized using the adjusted estimate. If at any time the estimate of contract profitability indicates an anticipated loss on the contract, the Company recognizes the total loss in the period it is identified. During the year ended December 31, 2020, no adjustment to any one contract was material to the Company’s Consolidated Financial Statements. The Company discloses only the transaction price allocated to its remaining performance obligations on contracts with an original duration greater than one year, which was $65.8 million as of December 31, 2020. The Company will recognize this revenue as performance obligations are satisfied, which is expected to occur within the next 18 months.

The Company recognizes an account receivable for satisfied performance obligations as it has an unconditional right to consideration and payment from the customer is due based solely on the passage of time. The Company receives payments from its customers on the accounts receivable based on the payment terms applicable to each individual contract and the customer pays in less than one year. Accounts receivables are included in “Accounts receivable, net” in the Consolidated Balance Sheets.

In addition, the timing of revenue recognition, billings and cash collections may result in revenues in excess of billings and contract retainage (contract assets), and billings in excess of revenues and customer deposits (contract liabilities). These assets and liabilities are reported on a

contract-by-contract

basis at the end of each reporting period in prepaid expenses and other assets (contract assets), and accrued expenses and other liabilities (contract liabilities). These assets and liabilities and changes in these assets and liabilities, respectively, were not material as of and for the year ended December 31, 2020.

Trex Commercial pays sales commissions that are directly attributable to identifiable contracts to certain of its employees. If the amortization period of the commission is one year or less, then the Company recognizes the commission expense as incurred. Otherwise, the Company capitalizes the commission and amortizes it on a straight-line basis over the life of the contract. Trex Commercial does not grant contractual product return rights to customers other than pursuant to its assurance product warranty. All shipping and handling fees invoiced to the customer are included in net sales and the related costs are included in cost of sales.

For each year in the three years ended December 31, 2020, net sales were disaggregated in the following tables by (1) market (2) timing of revenue recognition, and (3) type of contract. The tables also include a reconciliation of the respective disaggregated net sales with the Company’s reportable segments (in thousands):


Year Ended December 31, 2020	Reportable Segment
	Trex Residential		Trex Commercial		Total
Timing of Revenue Recognition and Type of Contract
Products transferred at a point in time and variable consideration contracts	$	827,792	$	—	$	827,792
Products transferred over time and fixed price contracts		—		53,039		53,039

	$	827,792	$	53,039	$	880,831


Year Ended December 31, 2019	Reportable Segment
	Trex Residential		Trex Commercial		Total
Timing of Revenue Recognition and Type of Contract
Products transferred at a point in time and variable consideration contracts	$	694,267	$	—	$	694,267
Products transferred over time and fixed price contracts		—		51,080		51,080

	$	694,267	$	51,080	$	745,347


Year Ended December 31, 2018	Reportable Segment
	Trex Residential		Trex Commercial		Total
Timing of Revenue Recognition and Type of Contract
Products transferred at a point in time and variable consideration contracts	$	613,229	$	—	$	613,229
Products transferred over time and fixed price contracts		—		71,021		71,021

	$	613,229	$	71,021	$	684,250

- Definition

The entire disclosure of revenue from contract with customer to transfer good or service and to transfer nonfinancial asset. Includes, but is not limited to, disaggregation of revenue, credit loss recognized from contract with customer, judgment and change in judgment related to contract with customer, and asset recognized from cost incurred to obtain or fulfill contract with customer. Excludes insurance and lease contracts.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-URI http://asc.fasb.org/topic&trid=49130388

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 10
-URI http://asc.fasb.org/extlink&oid=121604090&loc=SL49130551-203045

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 13
-Subparagraph (b)(2)
-URI http://asc.fasb.org/extlink&oid=121604090&loc=SL49130556-203045

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 12
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=121604090&loc=SL49130554-203045

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 9
-URI http://asc.fasb.org/extlink&oid=121604090&loc=SL49130550-203045

Reference 6: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 12
-Subparagraph (e)
-URI http://asc.fasb.org/extlink&oid=121604090&loc=SL49130554-203045

Reference 7: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 12
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=121604090&loc=SL49130554-203045

Reference 8: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 12
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=121604090&loc=SL49130554-203045

Reference 9: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 15
-URI http://asc.fasb.org/extlink&oid=121604090&loc=SL49130558-203045

Reference 10: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 12
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=121604090&loc=SL49130554-203045

+ Details

Stock-Based Compensation

12 Months Ended

Dec. 31, 2020

Disclosure of Compensation Related Costs, Share-based Payments [Abstract]

Stock-Based Compensation

13.	STOCK-BASED COMPENSATION

On April 30, 2014, the Company’s stockholders approved the Trex Company, Inc. 2014 Stock Incentive Plan (Plan), which was previously approved by the Board of Directors on February 19, 2014. The Plan amended and restated in its entirety the Trex Company, Inc. 2005 Stock Incentive Plan, as previously disclosed. The Plan is administered by the Compensation Committee of the Company’s Board of Directors. Stock-based compensation is granted to officers, directors and certain key employees in accordance with the provisions of the Plan. The Plan provides for grants of stock options, restricted stock, restricted stock units, stock appreciation rights (SARs), and unrestricted stock. The total aggregate number of shares of the Company’s common stock that may be issued under the Plan is 25,680,000 and as of December 31, 2020, the total number of shares available for future issuance was 11,253,930.

The Company recognizes stock-based compensation expense ratably over the period from grant date to the earlier of (1) the vesting date of the award, or (2) the date the grantee is eligible to retire without forfeiting the

award. For performance-based restricted stock and performance-based restricted stock units, expense is recognized ratably over the performance and vesting period of each tranche based on management’s judgment of the ultimate award that is probable to be paid out based on the achievement of the predetermined performance measures. For the employee stock purchase plan, compensation expense is recognized related to the discount on purchases. The following table summarizes the Company’s stock-based compensation expense (in thousands):


	Year Ended December 31,
	2020		2019		2018
Time-based restricted stock and restricted stock units	$	3,219	$	3,676	$	2,687
Performance-based restricted stock and restricted stock units		2,881		2,399		3,144
Stock appreciation rights		648		662		370
Employee stock purchase plan		383		193		143

Total stock-based compensation	$	7,131	$	6,930	$	6,344

Stock-based compensation expense is included in “Selling, general and administrative expenses” in the accompanying Consolidated Statements of Comprehensive Income.

Time-Based Restricted Stock and Time-Based Restricted Stock Units

The fair value of time-based restricted stock and time-based restricted stock units is determined based on the closing price of the Company’s shares on the grant date. Time-based restricted stock and time-based restricted stock units vest based on the terms of the awards. Unvested time-based restricted stock and unvested time-based restricted stock units are generally forfeitable upon the resignation of employment or termination of employment with cause. The total fair value of vested time-based restricted shares and vested time-based restricted stock units for the years ended December 31, 2020, 2019 and 2018 was $6.1 million, $6.0 million and $5.1 million, respectively. At December 31, 2020, there was $2.9 million of total compensation expense related to unvested time-based restricted stock and unvested time-based restricted stock units remaining to be recognized over a weighted-average period of approximately 1.7 years.

Time-based restricted stock and restricted stock unit activity under the Plan and all predecessor stock incentive plans is as follows:


	Time-based Restricted Stock and Restricted Stock Unit			Weighted-Average Grant Price Per Share
Nonvested at December 31, 2017		306,236		$	13.45
Granted		174,528		$	27.36
Vested		(169,100	)	$	13.33
Forfeited		(568	)	$	17.53

Nonvested at December 31, 2018		311,096		$	21.34
Granted		71,300		$	38.12
Vested		(162,650	)	$	18.67
Forfeited		(1,280	)	$	31.17

Nonvested at December 31, 2019		218,466		$	28.75
Granted		54,406		$	53.97
Vested		(111,036	)	$	30.94
Forfeited		(1,114	)	$	40.34

Nonvested at December 31, 2020		160,722		$	35.68

Performance-based Restricted Stock and Performance-Based Restricted Stock Units

The fair value of performance-based restricted stock and performance-based restricted stock units is determined based on the closing price of the Company’s shares on the grant date. Unvested performance-based restricted stock and unvested performance-based restricted stock units are generally forfeitable upon the resignation of employment or termination of employment with cause. The performance-based restricted shares and performance-based restricted stock units have a three-year vesting period, vesting

one-third

each year based on target earnings before interest, taxes, depreciation and amortization (EBITDA) for 1 year, cumulative 2 years and cumulative 3 years, respectively. The number of shares that will vest, with respect to each vesting, will be between 0% and 200% of the target number of shares. At December 31, 2020, 2019 and 2018 there was $1.7 million, $0.8 million and $1.6 million, respectively, of total compensation expense related to unvested performance-based restricted stock and unvested performance-based restricted stock units remaining to be recognized over a weighted-average period of approximately two years.

Performance-based restricted stock activity under the Plan is as follows:


	Performance-based Restricted Stock and Performance-based Restricted Stock Units			Weighted- Average Grant Price Per Share
Nonvested at December 31, 2017		233,316		$	12.93
Granted		161,140		$	17.63
Vested		(212,044	)	$	11.76
Forfeited		—		$	—

Nonvested at December 31, 2018		182,412		$	18.43
Granted		164,270		$	23.82
Vested		(222,004	)	$	15.55
Forfeited		(1,022	)	$	29.23

Nonvested at December 31, 2019		123,656		$	30.67
Granted		78,404		$	39.60
Vested		(128,762	)	$	28.87
Forfeited		(728	)	$	41.12

Nonvested at December 31, 2020		72,570		$	43.42

Stock Appreciation Rights

SARs are granted with a grant price equal to the closing market price of the Company’s common stock on the date of grant. These awards expire ten years after the date of grant and vest based on the terms of the individual awards. The SARs are generally forfeitable upon the resignation of employment or termination of employment with cause. The Company recognizes forfeitures as they occur. The Company recognizes compensation cost on a straight-line basis over the vesting period for the award.

As of December 31, 2020, there was $0.6 million of unrecognized compensation cost related to SARs. The fair value of each SAR is estimated on the date of grant using a Black-Scholes option-pricing model. For SARs issued in the years ended December 31, 2020, December 31, 2019 and December 31, 2018, respectively, the assumptions shown in the following table were used:


	Year Ended December 31,
	2020			2019			2018
Dividend yield		0	%		0	%		0	%
Average risk-free interest rate		1.3	%		2.5	%		2.7	%
Expected term (years)		5			5			5
Expected volatility		38.3	%		39.1	%		40.5	%

Dividend Yield.

The Company has never paid cash dividends on its common stock.

Average Risk-Free Interest Rate.

The Company uses the U.S. Treasury rate having a term that most closely resembles the expected term of the option.

Expected Term.

The expected term is the period of time that the SARs granted are expected to remain unexercised. SARs granted during the years ended December 31, 2020, December 31, 2019 and December 31, 2018 had a maximum term of ten years. The Company used historical exercise behavior with further consideration given to the class of employees to whom the equity awards were granted to estimate the expected term of the SAR.

Expected Volatility.

Volatility is a measure of the amount by which a financial variable such as a share price has fluctuated (historical volatility) or is expected to fluctuate (expected volatility) during a period. The Company has used the historical volatility over the average expected term of the options granted as the expected volatility.

The weighted-average grant date fair value of SARs granted during the years ended December 31, 2020, December 31, 2019 and December 31, 2018 was $17.81, $14.78 and $11.05, respectively.

SAR activity under the Plan and all predecessor stock incentive plans is as follows:


	SARs			Weighted-Average Grant Price Per Share		Weighted-Average Remaining Contractual Life (Years)		Aggregate Intrinsic Value as of December 31, 2020
Outstanding at December 31, 2017		556,232		$	6.73
Granted		42,520		$	28.30
Exercised		(121,800	)	$	2.64
Canceled		—		$	—

Outstanding at December 31, 2018		476,952		$	9.63
Granted		49,072		$	38.85
Exercised		(217,528	)	$	6.95
Canceled		(4,458	)	$	38.85

Outstanding at December 31, 2019		304,038		$	15.79
Granted		43,830		$	50.39
Exercised		(54,592	)	$	9.41
Canceled		—		$	—

Outstanding at December 31, 2020		293,276		$	22.15		5.4	$	18,058,138
Vested at December 31, 2020		237,323		$	17.05		4.7	$	15,821,712
Exercisable at December 31, 2020		237,323		$	17.05		4.7	$	15,821,712

Employee Stock Purchase Plan

The Company has an employee stock purchase plan (ESPP) that permits eligible employees to purchase shares of common stock of the Company at a purchase price which is the lesser of 85% of the market price on either the first day of the calendar quarter or the last day of the calendar quarter. Eligible employees may elect to

participate in the plan by

authorizing

payroll deductions of up to 15% of gross compensation for each payroll period. On the last day of each quarter, each participant’s contribution account is used to purchase the maximum number of whole shares of common stock determined by dividing the contribution account balance by the purchase price. The aggregate number of shares of common stock that may be purchased under the plan is 2,400,000. Through December 31, 2020, employees had purchased approximately 1,811,165 shares under the plan.

Employee Benefit Plans

12 Months Ended

Dec. 31, 2020

Postemployment Benefits [Abstract]

Employee Benefit Plans

14.	EMPLOYEE BENEFIT PLANS

The Company has two 401(k) Profit Sharing Plans for the benefit of its employees who meet certain eligibility requirements and it matches qualifying employee contributions. The Company’s contributions to the plans totaled $5.7 million, $4.6 million and $4.2 million for the years ended December 31, 2020, 2019 and 2018, respectively.

Income Taxes

12 Months Ended

Dec. 31, 2020

Income Tax Disclosure [Abstract]

Income Taxes

15.	INCOME TAXES

Income tax provision (benefit) consists of the following (in thousands):


	Year Ended December 31,
	2020		2019		2018
Current income tax provision:
Federal	$	35,423	$	30,306	$	33,578
State		10,455		6,952		7,674

		45,878		37,258		41,252

Deferred income tax provision:
Federal		12,603		6,928		988
State		522		778		49

		13,125		7,706		1,037

Total income tax provision	$	59,003	$	44,964	$	42,289

The income tax provision differs from the amount of income tax determined by applying the U.S. Federal statutory rate to income before taxes as a result of the following (in thousands):


	Year Ended December 31,
	2020			2019			2018
U.S. Federal statutory taxes	$	49,273		$	39,838		$	37,141
State and local taxes, net of U.S. Federal benefit		10,641			8,412			7,716
Permanent items		1,198			1,266			470
Excess tax benefits from vesting or settlement of stock compensation awards		(1,635	)		(3,540	)		(2,368	)
Federal credits		(565	)		(654	)		(662	)
Other		91			(358	)		(8	)

Total income tax provision	$	59,003		$	44,964		$	42,289

Deferred tax assets and liabilities consist of the following (in thousands):


	As of December 31,
	2020			2019
Deferred tax assets:
Net operating losses	$	43		$	88
Residential product warranty reserve		7,532			6,486
Stock-based compensation		1,071			1,055
Accruals not currently deductible and other		2,041			2,245
Inventories		5,548			5,780
Operating lease liability		9,081			10,618
State tax credit carryforwards		3,345			3,461

Gross deferred tax assets, before valuation allowance		28,661			29,733
Valuation allowance		(2,775	)		(2,988	)

Gross deferred tax assets, after valuation allowance		25,886			26,745

Deferred tax liabilities:
Depreciation		(29,792	)		(17,267	)
Operating lease right-of-use asset		(8,755	)		(10,162	)
Goodwill amortization		(5,775	)		(4,782	)
Inventories and other		(4,520	)		(4,365	)

Gross deferred tax liabilities		(48,842	)		(36,576	)

Net deferred tax liability	$	(22,956	)	$	(9,831	)

The Company recognizes deferred tax assets and liabilities based on the difference between the financial statement basis and tax basis of assets and liabilities using enacted rates expected to be in effect during the year in which the differences reverse. In accordance with accounting standards, the Company assesses the likelihood that its deferred tax assets will be realized. Deferred tax assets are reduced by a valuation allowance when, after considering all available positive and negative evidence, it is determined that it is more likely than not that some portion, or all, of the deferred tax asset will not be realized. As of December 31, 2020, the Company had a valuation allowance of $2.8 million against deferred tax assets it estimates will not be realized. The Company will analyze its position in subsequent reporting periods, considering all available positive and negative evidence, in determining the expected realization of its deferred tax assets.

The Company recognizes interest and penalties related to tax matters as a component of “Selling, general and administrative expenses” in the accompanying Consolidated Statements of Comprehensive Income. As of December 31, 2020, the Company has identified no uncertain tax position and, accordingly, has not recorded any unrecognized tax benefits or associated interest and penalties.

The Company operates in multiple tax jurisdictions and, in the normal course of business, its tax returns are subject to examination by various taxing authorities. Such examinations may result in future assessments by these taxing authorities, and the Company has accrued a liability when it believes that it is not more likely than not that it will realize the benefits of tax positions that it has taken or for the amount of any tax benefit that exceeds the cumulative probability threshold in accordance with accounting standards. As of December 31, 2020, for certain tax jurisdictions, tax years 2016 through 2019 remain subject to examination. The Company’s returns filed with the state of Utah for the tax years 2014 through 2018 are currently under examination. No material adjustments are expected as a result of the audit. The Company believes that adequate provisions have been made for all tax returns subject to examination. Sales made to foreign distributors are not taxable in any foreign jurisdictions as the Company does not have a taxable presence.

- Definition

The entire disclosure for income taxes. Disclosures may include net deferred tax liability or asset recognized in an enterprise's statement of financial position, net change during the year in the total valuation allowance, approximate tax effect of each type of temporary difference and carryforward that gives rise to a significant portion of deferred tax liabilities and deferred tax assets, utilization of a tax carryback, and tax uncertainties information.

+ References + Details

Segment Information

12 Months Ended

Dec. 31, 2020

Segment Reporting [Abstract]

Segment Information

16.	SEGMENT INFORMATION

The Company operates in two reportable segments:

•

Trex Residential manufactures composite decking and railing and related products marketed under the brand name Trex

. The products are sold to its distributors and two national retailers who, in turn, sell primarily to the residential market, which includes replacement, remodeling and new construction related to outdoor living products.

•

Trex Commercial designs, engineers, and markets modular and architectural railing and staging systems for commercial and multi-family market, including sports stadiums and performing arts venues. The segment’s products are sold through architects, specifiers, contractors, and others doing business within the segment’s commercial market.

The Company’s reportable segments have been determined in accordance with its internal management structure, which is organized based on residential and commercial operations. The Company evaluates performance of each segment primarily based on net sales and earnings before interest, taxes, depreciation and amortization (EBITDA). The Company uses net sales to assess performance and allocate resources as this measure represents the amount of business the segment engaged in during a given period of time, is an indicator of market growth and acceptance of segment products and represents the segment’s customers’ spending habits along with the amount of product the segment sells relative to its competitors. The Company uses EBITDA to assess performance and allocate resources because it believes that EBITDA facilitates performance comparison between the segments by eliminating interest, taxes, and depreciation and amortization charges to income.

Segment Data (in thousands):


	Net Sales		Net Income		EBITDA		Depreciation and Amortization		Income Tax Expense		Capital Expenditures		Total Assets
December 31, 2020
Trex Residential	$	827,792	$	171,197	$	244,817	$	17,131	$	57,488	$	171,784	$	676,948
Trex Commercial		53,039		4,434		6,758		809		1,515		1,039		93,544

Total	$	880,831	$	175,631	$	251,575	$	17,940	$	59,003	$	172,823	$	770,492

December 31, 2019
Trex Residential	$	694,267	$	142,811	$	199,020	$	13,413	$	44,292	$	65,399	$	503,883
Trex Commercial		51,080		1,927		3,210		618		672		1,866		88,356

Total	$	745,347	$	144,738	$	202,230	$	14,031	$	44,964	$	67,265	$	592,239

December 31, 2018
Trex Residential	$	613,229	$	131,823	$	186,268	$	13,216	$	41,421	$	31,392	$	380,682
Trex Commercial		71,021		2,749		6,868		3,251		868		2,424		84,440

Total	$	684,250	$	134,572	$	193,136	$	16,467	$	42,289	$	33,816	$	465,122

Reconciliation of Net Income (Loss) to EBITDA (in thousands):


	Net Income		Interest (Income) Expense, Net			Income Tax Expense		Depreciation and Amortization		EBITDA
December 31, 2020
Trex Residential	$	171,197	$	(999	)	$	57,488	$	17,131	$	244,817
Trex Commercial		4,434		—			1,515		809		6,758

Total	$	175,631	$	(999	)	$	59,003	$	17,940	$	251,575

December 31, 2019
Trex Residential	$	142,811	$	(1,496	)	$	44,292	$	13,413	$	199,020
Trex Commercial		1,927		(7	)		672		618		3,210

Total	$	144,738	$	(1,503	)	$	44,964	$	14,031	$	202,230

December 31, 2018
Trex Residential	$	131,823	$	(192	)	$	41,421	$	13,216	$	186,268
Trex Commercial		2,749		—			868		3,251		6,868

Total	$	134,572	$	(192	)	$	42,289	$	16,467	$	193,136

- Definition

The entire disclosure for reporting segments including data and tables. Reportable segments include those that meet any of the following quantitative thresholds a) it's reported revenue, including sales to external customers and intersegment sales or transfers is 10 percent or more of the combined revenue, internal and external, of all operating segments b) the absolute amount of its reported profit or loss is 10 percent or more of the greater, in absolute amount of 1) the combined reported profit of all operating segments that did not report a loss or 2) the combined reported loss of all operating segments that did report a loss c) its assets are 10 percent or more of the combined assets of all operating segments.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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+ Details

Seasonality

12 Months Ended

Dec. 31, 2020

Text Block [Abstract]

Seasonality

17.	SEASONALITY

The operating results for Trex Residential have historically varied from quarter to quarter. Seasonal, erratic or prolonged adverse weather conditions in certain geographic regions reduce the level of home improvement and construction activity and can shift demand for its products to a later period. As part of its normal business practice and consistent with industry practice, Trex Residential has historically offered incentive programs to its distributors and dealers to build inventory levels before the start of the prime deck-building season in order to ensure adequate availability of its product to meet anticipated seasonal consumer demand. The seasonal effects are often offset by the positive effect of the incentive programs. The operating results for Trex Commercial have not historically varied from quarter to quarter as a result of seasonality. However, they are driven by the timing of individual projects, which may vary significantly each period.

Commitments and Contingencies

12 Months Ended

Dec. 31, 2020

Commitments and Contingencies Disclosure [Abstract]

Commitments and Contingencies

18.	COMMITMENTS AND CONTINGENCIES

Legal Matters

The Company has lawsuits, as well as other claims, pending against it which are ordinary routine litigation and claims incidental to the business. Management has evaluated the merits of these lawsuits and claims and believes that their ultimate resolution will not have a material effect on the Company’s consolidated financial condition, results of operations, liquidity or competitive position.

Purchase Commitments

The Company fulfills requirements for raw materials under both purchase orders and supply contracts. In the year ended December 31, 2020, the Company purchased reclaimed wood fiber requirements under purchase orders and long-term supply commitments not exceeding

four years

. All of the Company’s scrap polyethylene, aluminum and stainless-steel purchases are under short-term supply contracts that may average approximately one to two years, for which pricing is negotiated as needed, or under purchase orders that do not involve long-term supply commitments.

The wood and polyethylene supply contracts generally provide that the Company is obligated to purchase all wood or polyethylene a supplier provides, if the wood or polyethylene meets certain specifications. The amount

of wood and polyethylene the Company is required to purchase under these contracts varies with the production of its suppliers and, accordingly, is not fixed or determinable. As of December 31, 2020, the Company has purchase commitments under material supply contracts of $33.6 million

and

$15.0 million for the years ending December 31, 2021 and 2022, respectively, and a total of $22.7 million for the years ending December 31, 2023 and 2024.

Product Warranty

The Company warrants that its Trex Residential products will be free from material defects in workmanship and materials. This warranty generally extends for a period of 25 years for residential use and 10 years for commercial use, excluding Trex Signature

Railing, which has a warranty period of 25 years for both residential and commercial use. The Company further warrants that Trex Transcend

, Trex Enhance

, Trex Select

and Universal Fascia products will not fade in color more than a certain amount and will be resistant to permanent staining from food substances or mold, provided the stain is cleaned within seven days of appearance. This warranty extends for a period of 25 years for residential use and 10 years for commercial use. If there is a breach of such warranties, the Company has an obligation either to replace the defective product or refund the purchase price. Depending on the product and its use, the Company also warrants its Trex Commercial products will be free of manufacturing defects for one to three years.

The Company continues to receive and settle claims for decking products manufactured at its Nevada facility prior to 2007 that exhibit surface flaking and maintains a warranty reserve to provide for the settlement of these claims. Estimating the warranty reserve for surface flaking claims requires management to estimate (1) the number of claims to be settled with payment and (2) the average cost to settle each claim.

To estimate the number of claims to be settled with payment, the Company utilizes actuarial techniques to determine a reasonable possible range of claims to be received and the percentage of those claims that will ultimately require payment (collectively, elements). Estimates for these elements are quantified using a range of assumptions derived from claim count history and the identification of factors influencing the claim counts to determine its best estimate of future claims for which to record a related liability. The cost per claim varies due to a number of factors, including the size of affected decks, the availability and type of replacement material used, the cost of production of replacement material and the method of claim settlement.

The Company monitors surface flaking claims activity each quarter for indications that its estimates require revision. Typically, a majority of surface flaking claims received in a year are received during the summer outdoor season, which spans the second and third quarters. It has been the Company’s practice to utilize the actuarial techniques discussed above during the third quarter, after a significant portion of all claims has been received for the fiscal year and variances to annual claims expectations are more meaningful.

The number of incoming claims received in the year ended December 31, 2020 was higher than the number of claims received in the year ended December 31, 2019 and exceeded the Company’s expectations for 2020. Prior to 2020, the number of incoming claims received declined each year since 2009. After evaluating the rise in incoming claims in its actuarial analysis, the Company increased its estimate of the number of future claims to be settled with payment. Average cost per claim experienced in the year ended December 31, 2020 was lower than that experienced in the year ended December 31, 2019, but slightly higher than the Company’s expectations for 2020. The Company estimates that average cost per claim will increase in future years, primarily due to inflation.

As a result of the increase in estimated future claims and expected rise in future average cost per claim, in the three-month period ended September 30, 2020, the Company recorded a provision of $6.5 million to its warranty reserve for the future settlement of surface flaking claims. The Company believes its reserve at December 31, 2020 is sufficient to cover future surface flaking obligations.

The Company’s analysis is based on currently known facts and a number of assumptions, as discussed above, and current expectations. Projecting future events such as the number of claims to be received, the number of claims that will require payment and the average cost of claims could cause the actual warranty liabilities to be higher or lower than those projected, which could materially affect the Company’s financial condition, results of operations or cash flows. The Company estimates that the annual number of claims received will continue to decline over time and that the average cost per claim will increase slightly, primarily due to inflation. If the level of claims received or average cost per claim differs materially from expectations, it could result in additional increases or decreases to the warranty reserve and a decrease or increase in earnings and cash flows in future periods. The Company estimates that a 10% change in the expected number of remaining claims to be settled with payment or the expected cost to settle claims may result in approximately a $2.1 million change in the surface flaking warranty reserve.

The Company also maintains a warranty reserve for the settlement of other residential product warranty claims and records the provision at the time of product sale.

The following is a reconciliation of the Company’s residential product warranty reserve (in thousands):


	Year Ended December 31, 2020
	Surface Flaking			Other Residential			Total
Beginning balance, January 1	$	19,024		$	6,470		$	25,494
Provisions and changes in estimates		6,479			3,382			9,861
Settlements made during the period		(4,178	)		(1,704	)		(5,882	)

Ending balance, December 31	$	21,325		$	8,148		$	29,473


	Year Ended December 31, 2019
	Surface Flaking			Other Residential			Total
Beginning balance, January 1	$	23,951		$	6,803		$	30,754
Provisions and changes in estimates		—			979			979
Settlements made during the period		(4,927	)		(1,312	)		(6,239	)

Ending balance, December 31	$	19,024		$	6,470		$	25,494

Interim Financial Data (Unaudited)

12 Months Ended

Dec. 31, 2020

Quarterly Financial Information Disclosure [Abstract]

Interim Financial Data (Unaudited)

19.	INTERIM FINANCIAL DATA (Unaudited)


	Three Months Ended
	December 31, 2020		September 30, 2020		June 30, 2020		March 31, 2020		December 31, 2019		September 30, 2019		June 30, 2019		March 31, 2019
	(In thousands, except share and per share data)
Net sales	$	228,286	$	231,502	$	220,648	$	200,395	$	164,772	$	194,551	$	206,453	$	179,571
Gross profit	$	92,392	$	84,964	$	92,405	$	89,696	$	71,263	$	82,431	$	83,444	$	69,365
Net income	$	43,301	$	42,710	$	47,218	$	42,402	$	35,497	$	41,976	$	35,710	$	31,555
Basic earnings per common share	$	0.37	$	0.37	$	0.41	$	0.37	$	0.31	$	0.36	$	0.31	$	0.27
Basic weighted average common shares outstanding		115,791,757		115,773,030		115,733,934		116,259,058		116,591,434		116,800,120		116,972,384		117,086,956
Diluted earnings per common share	$	0.37	$	0.37	$	0.41	$	0.37	$	0.31	$	0.36	$	0.31	$	0.27
Diluted weighted average common shares outstanding		116,169,754		116,134,623		116,061,988		116,647,442		117,025,466		117,209,206		117,375,080		117,658,354

and construction activity and can shift demand for its products to a later period. The operating results for Trex Commercial have not historically varied from quarter to quarter as a result of seasonality; however, they are driven by the timing of individual projects, which may vary significantly each period.

On July 29, 2020, the Company’s Board of Directors approved a

two-for-one

stock split of the Company’s common stock, par value, $0.01. The stock split was in the form of a stock dividend distributed on September 14, 2020, to stockholders of record at the close of business on August 19, 2020. The stock split entitled each stockholder to receive one additional share of common stock for each share they held as of the record date. All common stock share and per share data for all periods presented in the accompanying unaudited condensed consolidated financial statements and notes thereto have been retroactively adjusted to reflect the stock split.

Schedule II - Valuation and Qualifying Accounts and Reserves

12 Months Ended

Dec. 31, 2020

SEC Schedule, 12-09, Valuation and Qualifying Accounts [Abstract]

Schedule II - Valuation and Qualifying Accounts and Reserves

TREX COMPANY, INC.

SCHEDULE II—VALUATION AND QUALIFYING ACCOUNTS AND RESERVES

(In thousands)


Descriptions	Balance at Beginning of Period		Additions Charged to Cost and Expenses		Deductions			Balance at End of Period
Year ended December 31, 2020:
Trex Residential product warranty reserve	$	25,494	$	9,861	$	(5,882	)	$	29,473

Income tax valuation allowance	$	2,988	$	1	$	(214	)	$	2,775

Year ended December 31, 2019:
Trex Residential product warranty reserve	$	30,754	$	979	$	(6,239	)	$	25,494

Income tax valuation allowance	$	3,015	$	—	$	(27	)	$	2,988

Year ended December 31, 2018:
Trex Residential product warranty reserve	$	34,999	$	1,104	$	(5,349	)	$	30,754

Income tax valuation allowance	$	3,096	$	—	$	(81	)	$	3,015

Summary of Significant Accounting Policies (Policies)

12 Months Ended

Dec. 31, 2020

Accounting Policies [Abstract]

Basis of Accounting

Use of Estimates

Cash and Cash Equivalents

Cash equivalents consist of highly liquid investments purchased with original maturities of

three months or less.

Concentrations and Credit Risk

three customers of Trex Residential represented approximately 57% of the Company’s total net sales. For the year ended December 31, 2018,

For each year ended December 31, 2020, 2019, and 2018, approximately 28%, 27%, and 33%, respectively, of the Company’s materials purchases at Trex Residential were purchased from its

four largest suppliers.

Inventories

Inventories for the Company’s composite decking and railing products are valued at the lower of cost

(last-in,

first-out,

Inventories for the Company’s railing and staging products at Trex Commercial for the commercial and multi-family market are valued at the lower of cost

(first-in,

first-out

or FIFO method), using actual cost, and net realizable value.

Work-in

process includes estimated production costs.

Property, Plant and Equipment


Buildings		40 years
Machinery and equipment		3-11 years
Furniture and equipment		10 years
Forklifts and tractors		5 years
Computer equipment and software		5 years

Leasehold improvements are amortized over the shorter of the lease term or the estimated useful life of the asset.

assets

held for sale are stated at the lower of cost or fair value less cost to sell.

Leases

right-of-use

non-lease

components, which are accounted for separately. Consideration for

non-lease

components is stated on a stand-alone basis in the applicable agreements.

Fair Value Measurement

•

Level 1 – Quoted prices for identical instruments in active markets.

•

Goodwill

Intangibles – Goodwill and Other

For the years ended December 31, 2020, 2019, and 2018, the Company completed its annual impairment test of goodwill utilizing the qualitative assessment and concluded it was not more likely than

Product Warranty

10 years for commercial use. With respect to Trex Signature

Railing, the warranty period is 25 years for both residential and commercial use. With respect to the Company’s Transcend

, Enhance

, Select

available

information. Management reviews and adjusts these estimates, if necessary, based on the differences between

actual

experience and historical estimates.

Treasury Stock

Revenue Recognition

Effective January 1, 2018, the Company retrospectively adopted the requirements of Financial Accounting Standards Board (FASB) Accounting Standards Update (ASU)

2014-09,

Trex Residential Products.

Trex Residential principally generates revenue from the manufacture and sale of its high-performance,

low-maintenance,

eco-friendly

Trex Commercial Products.

Trex Commercial satisfies its performance obligation over

time

catch-up

Stock-Based Compensation

Income Taxes

Research and Development Costs

Advertising Costs

For the years ended December 31, 2020, 2019, and 2018, branding expenses, including advertising expenses as described above, were $31.7 million, $35.7 million, and $35.0 million, respectively.

Fair Value of Financial Instruments

Recently Adopted Accounting Standards

In August 2018, the Financial Accounting Standards Board (FASB) issued Accounting Standards Update (ASU)

No. 2018-15,

“

Intangibles – Goodwill and Other –

Internal-Use

Software (Subtopic

350-40):

Customer’s Accounting for Implementation Costs Incurred in a Cloud Computing Arrangement That Is a Service Contract (a consensus of FASB Emerging Issues Task Force)

internal-use

In January 2017, the FASB issued ASU

No. 2017-04,

“

Intangibles—Goodwill and Other (Topic 350), Simplifying the Test for Goodwill Impairment

In June 2016, the FASB issued ASU

2016-13,

“

Financial Instruments – Credit Losses (Topic 326): Measurement of Credit Losses in Financial Instruments

New Accounting Standards Not Yet Adopted

In March 2020, the FASB issued ASU

No. 2020-04,

“

Reference Rate Reform (Topic 848): Facilitation of the Effects of Reference Rate Reform on Financial Reporting

”. The guidance provides temporary optional expedients and exceptions related to contract modifications and hedge accounting to ease entities’ financial

In December 2019, the FASB issued ASU

No. 2019-12,

“

Income Taxes (Topic 740), Simplifying the Accounting for Income Taxes

step-up

Summary of Significant Accounting Policies (Tables)

12 Months Ended

Dec. 31, 2020

Accounting Policies [Abstract]

Estimated Useful Lives of Property Plant and Equipment


Buildings		40 years
Machinery and equipment		3-11 years
Furniture and equipment		10 years
Forklifts and tractors		5 years
Computer equipment and software		5 years

Inventories (Tables)

12 Months Ended

Dec. 31, 2020

Inventory Disclosure [Abstract]

Summary of Inventories

Inventories at LIFO value consist of the following as of December 31 (in thousands):


	2020			2019
Finished goods	$	39,048		$	42,281
Raw materials		44,475			31,686

Total FIFO inventories		83,523			73,967
Reserve to adjust inventories to LIFO value		(16,821	)		(19,062	)

Total LIFO inventories	$	66,702		$	54,905

Prepaid Expenses and Other Assets (Tables)

12 Months Ended

Dec. 31, 2020

Text Block [Abstract]

Summary of Prepaid Expenses and Other Assets

Prepaid expenses and other assets consist of the following as of December 31 (in thousands):


	2020		2019
Prepaid expenses	$	7,285	$	8,282
Revenues in excess of billings		6,612		6,664
Contract retainage		2,267		1,832
Income tax receivable		7,823		2,675
Other		1,323		350

Total prepaid expenses and other assets	$	25,310	$	19,803

Property, Plant and Equipment (Tables)

12 Months Ended

Dec. 31, 2020

Property, Plant and Equipment [Abstract]

Summary of Property, Plant and Equipment

Property, plant and equipment consist of the following as of December 31 (in thousands):


	2020			2019
Machinery and equipment	$	312,870		$	248,633
Building and improvements		61,860			51,547
Forklifts and tractors		16,003			10,870
Computer equipment		11,948			10,647
Furniture and fixtures		1,534			1,441
Construction in process		157,465			59,257
Land		11,351			11,417

Total property, plant and equipment		573,031			393,812
Accumulated depreciation		(236,494	)		(222,512	)

Total property, plant and equipment, net	$	336,537		$	171,300

Accrued Expenses and Other Liabilities (Tables)

12 Months Ended

Dec. 31, 2020

Payables and Accruals [Abstract]

Summary of Accrued Expenses and Other Liabilities

Accrued expenses and other liabilities consist of the following as of December 31 (in thousands):


	2020		2019
Sales and marketing	$	22,938	$	28,402
Compensation and benefits		21,156		13,475
Operating lease liabilities		6,708		7,079
Manufacturing costs		3,641		2,564
Customer deposits		1,174		2,905
Billings in excess of revenues		1,244		816
Other		5,470		3,024

Total accrued expenses	$	62,331	$	58,265

Debt (Tables)

12 Months Ended

Dec. 31, 2020

Debt Disclosure [Abstract]

Schedule of Debt


Pricing Tier	Consolidated Debt to Consolidated EBITDA Ratio	Eurodollar Rate Loans / LIBOR Index Rate			Base Rate Loans			Revolving B Commitment Fee
1	> 2.50:1.00		2.75	%		1.75	%		0.60	%
2	< 2.50:1.00 but > 2.00:1.00		2.50	%		1.50	%		0.55	%
3	< 2.00:1.00 but > 1.50:1.00		2.25	%		1.25	%		0.50	%
4	< 1.50:1.00		1.80	%		0.80	%		0.45	%

Leases (Tables)

12 Months Ended

Dec. 31, 2020

Leases [Abstract]

Supplemental Cash Flow information and Supplemental balance sheet information related to operating leases to operating leases


	For the Year Ended December 31
Supplemental Cash Flow Information	2020		2019
Cash paid for amounts included in the measurement of operating lease liabilities	$	8,736	$	8,479
Operating ROU assets obtained in exchange for lease liabilities	$	1,427	$	1,319

Supplemental Balance Sheet Information	December 31, 2020		December 31, 2019
Operating lease ROU assets	$	34,382	$	40,049
Operating lease liabilities:
Accrued expenses and other current liabilities	$	6,708	$	7,079
Operating lease liabilities		28,579		34,242

Total operating lease liabilities	$	35,287	$	41,321

Maturities of operating lease liabilities

The following table summarizes maturities of operating lease liabilities at December 31, 2020 (in thousands):


Maturities of operating lease liabilities
2021	$	7,835
2022		7,345
2023		6,608
2024		6,265
2025		4,480
Thereafter		6,599

Total lease payments		39,132
Less imputed interest		(3,845	)

Total operating liabilities	$	35,287

Stockholders' Equity (Tables)

12 Months Ended

Dec. 31, 2020

Equity [Abstract]

Computation of Basic and Diluted Earnings Per Share

The following table sets forth the computation of basic and diluted earnings per share (in thousands, except share and per share data):


	Year Ended December 31,
	2020		2019		2018
Numerator:
Net income	$	175,631	$	144,738	$	134,572

Denominator:
Basic weighted average shares outstanding		115,888,859		116,861,194		117,479,340
Effect of dilutive securities:
Stock appreciation rights		192,579		248,850		353,400
Restricted stock		171,428		205,454		301,864

Diluted weighted average shares outstanding		116,252,866		117,315,498		118,134,604

Basic earnings per share	$	1.52	$	1.24	$	1.15

Diluted earnings per share	$	1.51	$	1.24	$	1.14

Antidilutive Securities Excluded from Computation of Earnings Per Share

The computation of diluted earnings per share excludes the following potentially dilutive securities because the effect would be anti-dilutive:


	Year Ended December 31,
	2020		2019		2018
Restricted stock		—		—		428
Stock appreciation rights		14,697		41,540		26,694

Revenue From Contracts With Customers (Tables)

12 Months Ended

Dec. 31, 2020

Revenue from Contract with Customer [Abstract]

Summary of Disaggregated Net Sales

The tables also include a reconciliation of the respective disaggregated net sales with the Company’s reportable segments (in thousands):


Year Ended December 31, 2020	Reportable Segment
	Trex Residential		Trex Commercial		Total
Timing of Revenue Recognition and Type of Contract
Products transferred at a point in time and variable consideration contracts	$	827,792	$	—	$	827,792
Products transferred over time and fixed price contracts		—		53,039		53,039

	$	827,792	$	53,039	$	880,831


Year Ended December 31, 2019	Reportable Segment
	Trex Residential		Trex Commercial		Total
Timing of Revenue Recognition and Type of Contract
Products transferred at a point in time and variable consideration contracts	$	694,267	$	—	$	694,267
Products transferred over time and fixed price contracts		—		51,080		51,080

	$	694,267	$	51,080	$	745,347


Year Ended December 31, 2018	Reportable Segment
	Trex Residential		Trex Commercial		Total
Timing of Revenue Recognition and Type of Contract
Products transferred at a point in time and variable consideration contracts	$	613,229	$	—	$	613,229
Products transferred over time and fixed price contracts		—		71,021		71,021

	$	613,229	$	71,021	$	684,250

Stock-Based Compensation (Tables)

12 Months Ended

Dec. 31, 2020

Summary of Stock-Based Compensation Expense

The following table summarizes the Company’s stock-based compensation expense (in thousands):


	Year Ended December 31,
	2020		2019		2018
Time-based restricted stock and restricted stock units	$	3,219	$	3,676	$	2,687
Performance-based restricted stock and restricted stock units		2,881		2,399		3,144
Stock appreciation rights		648		662		370
Employee stock purchase plan		383		193		143

Total stock-based compensation	$	7,131	$	6,930	$	6,344

Summary of Assumptions Used to Estimate Fair Value of Each SAR

For SARs issued in the years ended December 31, 2020, December 31, 2019 and December 31, 2018, respectively, the assumptions shown in the following table were used:


	Year Ended December 31,
	2020			2019			2018
Dividend yield		0	%		0	%		0	%
Average risk-free interest rate		1.3	%		2.5	%		2.7	%
Expected term (years)		5			5			5
Expected volatility		38.3	%		39.1	%		40.5	%

SAR Activity

SAR activity under the Plan and all predecessor stock incentive plans is as follows:


	SARs			Weighted-Average Grant Price Per Share		Weighted-Average Remaining Contractual Life (Years)		Aggregate Intrinsic Value as of December 31, 2020
Outstanding at December 31, 2017		556,232		$	6.73
Granted		42,520		$	28.30
Exercised		(121,800	)	$	2.64
Canceled		—		$	—

Outstanding at December 31, 2018		476,952		$	9.63
Granted		49,072		$	38.85
Exercised		(217,528	)	$	6.95
Canceled		(4,458	)	$	38.85

Outstanding at December 31, 2019		304,038		$	15.79
Granted		43,830		$	50.39
Exercised		(54,592	)	$	9.41
Canceled		—		$	—

Outstanding at December 31, 2020		293,276		$	22.15		5.4	$	18,058,138
Vested at December 31, 2020		237,323		$	17.05		4.7	$	15,821,712
Exercisable at December 31, 2020		237,323		$	17.05		4.7	$	15,821,712

Time-Based Restricted Stock and Time-Based Restricted Stock Units [Member]

Restricted Stock Activity

Time-based restricted stock and restricted stock unit activity under the Plan and all predecessor stock incentive plans is as follows:


	Time-based Restricted Stock and Restricted Stock Unit			Weighted-Average Grant Price Per Share
Nonvested at December 31, 2017		306,236		$	13.45
Granted		174,528		$	27.36
Vested		(169,100	)	$	13.33
Forfeited		(568	)	$	17.53

Nonvested at December 31, 2018		311,096		$	21.34
Granted		71,300		$	38.12
Vested		(162,650	)	$	18.67
Forfeited		(1,280	)	$	31.17

Nonvested at December 31, 2019		218,466		$	28.75
Granted		54,406		$	53.97
Vested		(111,036	)	$	30.94
Forfeited		(1,114	)	$	40.34

Nonvested at December 31, 2020		160,722		$	35.68

Performance-Based Restricted Stock and Performance-Based Restricted Stock Units [Member]

Restricted Stock Activity

Performance-based restricted stock activity under the Plan is as follows:


	Performance-based Restricted Stock and Performance-based Restricted Stock Units			Weighted- Average Grant Price Per Share
Nonvested at December 31, 2017		233,316		$	12.93
Granted		161,140		$	17.63
Vested		(212,044	)	$	11.76
Forfeited		—		$	—

Nonvested at December 31, 2018		182,412		$	18.43
Granted		164,270		$	23.82
Vested		(222,004	)	$	15.55
Forfeited		(1,022	)	$	29.23

Nonvested at December 31, 2019		123,656		$	30.67
Granted		78,404		$	39.60
Vested		(128,762	)	$	28.87
Forfeited		(728	)	$	41.12

Nonvested at December 31, 2020		72,570		$	43.42

Income Taxes (Tables)

12 Months Ended

Dec. 31, 2020

Income Tax Disclosure [Abstract]

Income Tax Provision (Benefit)

Income tax provision (benefit) consists of the following (in thousands):


	Year Ended December 31,
	2020		2019		2018
Current income tax provision:
Federal	$	35,423	$	30,306	$	33,578
State		10,455		6,952		7,674

		45,878		37,258		41,252

Deferred income tax provision:
Federal		12,603		6,928		988
State		522		778		49

		13,125		7,706		1,037

Total income tax provision	$	59,003	$	44,964	$	42,289

Reconciliation of Differences between Income Tax Provision and Income Tax Determined by Applying US Federal Statutory Rate

The income tax provision differs from the amount of income tax determined by applying the U.S. Federal statutory rate to income before taxes as a result of the following (in thousands):


	Year Ended December 31,
	2020			2019			2018
U.S. Federal statutory taxes	$	49,273		$	39,838		$	37,141
State and local taxes, net of U.S. Federal benefit		10,641			8,412			7,716
Permanent items		1,198			1,266			470
Excess tax benefits from vesting or settlement of stock compensation awards		(1,635	)		(3,540	)		(2,368	)
Federal credits		(565	)		(654	)		(662	)
Other		91			(358	)		(8	)

Total income tax provision	$	59,003		$	44,964		$	42,289

Schedule of Deferred Tax Assets and Liabilities

Deferred tax assets and liabilities consist of the following (in thousands):


	As of December 31,
	2020			2019
Deferred tax assets:
Net operating losses	$	43		$	88
Residential product warranty reserve		7,532			6,486
Stock-based compensation		1,071			1,055
Accruals not currently deductible and other		2,041			2,245
Inventories		5,548			5,780
Operating lease liability		9,081			10,618
State tax credit carryforwards		3,345			3,461

Gross deferred tax assets, before valuation allowance		28,661			29,733
Valuation allowance		(2,775	)		(2,988	)

Gross deferred tax assets, after valuation allowance		25,886			26,745

Deferred tax liabilities:
Depreciation		(29,792	)		(17,267	)
Operating lease right-of-use asset		(8,755	)		(10,162	)
Goodwill amortization		(5,775	)		(4,782	)
Inventories and other		(4,520	)		(4,365	)

Gross deferred tax liabilities		(48,842	)		(36,576	)

Net deferred tax liability	$	(22,956	)	$	(9,831	)

Segment Information (Tables)

12 Months Ended

Dec. 31, 2020

Segment Reporting [Abstract]

Details of Segment Information

Segment Data (in thousands):


	Net Sales		Net Income		EBITDA		Depreciation and Amortization		Income Tax Expense		Capital Expenditures		Total Assets
December 31, 2020
Trex Residential	$	827,792	$	171,197	$	244,817	$	17,131	$	57,488	$	171,784	$	676,948
Trex Commercial		53,039		4,434		6,758		809		1,515		1,039		93,544

Total	$	880,831	$	175,631	$	251,575	$	17,940	$	59,003	$	172,823	$	770,492

December 31, 2019
Trex Residential	$	694,267	$	142,811	$	199,020	$	13,413	$	44,292	$	65,399	$	503,883
Trex Commercial		51,080		1,927		3,210		618		672		1,866		88,356

Total	$	745,347	$	144,738	$	202,230	$	14,031	$	44,964	$	67,265	$	592,239

December 31, 2018
Trex Residential	$	613,229	$	131,823	$	186,268	$	13,216	$	41,421	$	31,392	$	380,682
Trex Commercial		71,021		2,749		6,868		3,251		868		2,424		84,440

Total	$	684,250	$	134,572	$	193,136	$	16,467	$	42,289	$	33,816	$	465,122

Schedule of Reconciliation of Net Income to EBITDA

Reconciliation of Net Income (Loss) to EBITDA (in thousands):


	Net Income		Interest (Income) Expense, Net			Income Tax Expense		Depreciation and Amortization		EBITDA
December 31, 2020
Trex Residential	$	171,197	$	(999	)	$	57,488	$	17,131	$	244,817
Trex Commercial		4,434		—			1,515		809		6,758

Total	$	175,631	$	(999	)	$	59,003	$	17,940	$	251,575

December 31, 2019
Trex Residential	$	142,811	$	(1,496	)	$	44,292	$	13,413	$	199,020
Trex Commercial		1,927		(7	)		672		618		3,210

Total	$	144,738	$	(1,503	)	$	44,964	$	14,031	$	202,230

December 31, 2018
Trex Residential	$	131,823	$	(192	)	$	41,421	$	13,216	$	186,268
Trex Commercial		2,749		—			868		3,251		6,868

Total	$	134,572	$	(192	)	$	42,289	$	16,467	$	193,136

Commitments and Contingencies (Tables)

12 Months Ended

Dec. 31, 2020

Commitments and Contingencies Disclosure [Abstract]

Summary of Reconciliation of Company's Residential Product Warranty Reserve

The following is a reconciliation of the Company’s residential product warranty reserve (in thousands):


	Year Ended December 31, 2020
	Surface Flaking			Other Residential			Total
Beginning balance, January 1	$	19,024		$	6,470		$	25,494
Provisions and changes in estimates		6,479			3,382			9,861
Settlements made during the period		(4,178	)		(1,704	)		(5,882	)

Ending balance, December 31	$	21,325		$	8,148		$	29,473


	Year Ended December 31, 2019
	Surface Flaking			Other Residential			Total
Beginning balance, January 1	$	23,951		$	6,803		$	30,754
Provisions and changes in estimates		—			979			979
Settlements made during the period		(4,927	)		(1,312	)		(6,239	)

Ending balance, December 31	$	19,024		$	6,470		$	25,494

Interim Financial Data (Unaudited) (Tables)

12 Months Ended

Dec. 31, 2020

Quarterly Financial Information Disclosure [Abstract]

Summary of Interim Financial Data


	Three Months Ended
	December 31, 2020		September 30, 2020		June 30, 2020		March 31, 2020		December 31, 2019		September 30, 2019		June 30, 2019		March 31, 2019
	(In thousands, except share and per share data)
Net sales	$	228,286	$	231,502	$	220,648	$	200,395	$	164,772	$	194,551	$	206,453	$	179,571
Gross profit	$	92,392	$	84,964	$	92,405	$	89,696	$	71,263	$	82,431	$	83,444	$	69,365
Net income	$	43,301	$	42,710	$	47,218	$	42,402	$	35,497	$	41,976	$	35,710	$	31,555
Basic earnings per common share	$	0.37	$	0.37	$	0.41	$	0.37	$	0.31	$	0.36	$	0.31	$	0.27
Basic weighted average common shares outstanding		115,791,757		115,773,030		115,733,934		116,259,058		116,591,434		116,800,120		116,972,384		117,086,956
Diluted earnings per common share	$	0.37	$	0.37	$	0.41	$	0.37	$	0.31	$	0.36	$	0.31	$	0.27
Diluted weighted average common shares outstanding		116,169,754		116,134,623		116,061,988		116,647,442		117,025,466		117,209,206		117,375,080		117,658,354

Business and Organization - Additional Information (Detail)	12 Months Ended
	Dec. 31, 2020 Segment
Accounting Policies [Abstract]
Number of reportable segments	2

Summary of Significant Accounting Policies - Additional Information (Detail) $ in Thousands	12 Months Ended
	Dec. 31, 2020 USD ($) Institution Customer Supplier	Dec. 31, 2019 USD ($) Customer	Dec. 31, 2018 USD ($) Customer
Schedule Of Significant Accounting Policies [Line Items]
Maximum term of original maturities to classify as cash equivalent	3 months
Number of financial institutions where deposits are maintained \| Institution	1
Valuation allowance	$ 0	$ 0
Number of customers that accounted for 10% or more of net sales \| Customer	3	3	2
Number of customer accounted for 10% or more account receivable \| Customer	2	3
Number of largest raw material suppliers \| Supplier	4
Excess of the replacement cost of inventory over the LIFO value of inventory	$ (16,821)	$ (19,062)
Annual impairment test of goodwill	0	0	$ 0
Goodwill	68,500
Valuation allowance	2,775	2,988
Research and Development costs	3,400	4,500	4,200
Prepaid expenses for production costs of advertising	10	500
Branding Expenses	31,700	35,700	$ 35,000
Unpaid Liabilities relates to property plant and equipment	$ 12,900	$ 800
Operating leases with an initial term	12 months or less
Maximum [Member]
Schedule Of Significant Accounting Policies [Line Items]
Operating Lease terms	8 years
Minimum [Member]
Schedule Of Significant Accounting Policies [Line Items]
Operating Lease terms	1 year
Residential Use [Member]
Schedule Of Significant Accounting Policies [Line Items]
Warranty period	25 years
Residential Use [Member] \| Transcend Enhance Select And Universal Fascia Product [Member]
Schedule Of Significant Accounting Policies [Line Items]
Warranty period	25 years
Residential Use [Member] \| Trex Signature Railing [Member]
Schedule Of Significant Accounting Policies [Line Items]
Warranty period	25 years
Commercial Use [Member]
Schedule Of Significant Accounting Policies [Line Items]
Warranty period	10 years
Commercial Use [Member] \| Transcend Enhance Select And Universal Fascia Product [Member]
Schedule Of Significant Accounting Policies [Line Items]
Warranty period	10 years
Commercial Use [Member] \| Trex Signature Railing [Member]
Schedule Of Significant Accounting Policies [Line Items]
Warranty period	25 years
Commercial Use [Member] \| Maximum [Member] \| Commercial Railing And Staging Systems [Member]
Schedule Of Significant Accounting Policies [Line Items]
Warranty period	3 years
Commercial Use [Member] \| Minimum [Member] \| Commercial Railing And Staging Systems [Member]
Schedule Of Significant Accounting Policies [Line Items]
Warranty period	1 year
Sales Revenue, Net [Member] \| Customer Concentration Risk [Member] \| Minimum [Member]
Schedule Of Significant Accounting Policies [Line Items]
Concentration risk as percentage of total	10.00%	10.00%	10.00%
Sales Revenue, Net [Member] \| Customer Concentration Risk [Member] \| Customer One [Member]
Schedule Of Significant Accounting Policies [Line Items]
Concentration risk as percentage of total	56.00%	57.00%	42.00%
Accounts Receivable [Member] \| Customer Concentration Risk [Member] \| Customer One [Member]
Schedule Of Significant Accounting Policies [Line Items]
Concentration risk as percentage of total	27.00%	30.00%
Accounts Receivable [Member] \| Customer Concentration Risk [Member] \| Customer Two [Member]
Schedule Of Significant Accounting Policies [Line Items]
Concentration risk as percentage of total	15.00%	24.00%
Accounts Receivable [Member] \| Customer Concentration Risk [Member] \| Customer Three [Member]
Schedule Of Significant Accounting Policies [Line Items]
Concentration risk as percentage of total		10.00%
Raw Materials [Member] \| Supplier Concentration Risk [Member]
Schedule Of Significant Accounting Policies [Line Items]
Concentration risk as percentage of total	28.00%	27.00%	33.00%

Summary of Significant Accounting Policies - Estimated Useful Lives of Property Plant and Equipment (Detail)	12 Months Ended
	Dec. 31, 2020
Buildings [Member]
Property, Plant and Equipment [Line Items]
Property, plant, and equipment estimated useful life	40 years
Furniture and Fixtures [Member]
Property, Plant and Equipment [Line Items]
Property, plant, and equipment estimated useful life	10 years
Forklifts and Tractors [Member]
Property, Plant and Equipment [Line Items]
Property, plant, and equipment estimated useful life	5 years
Computer Equipment and Software [Member]
Property, Plant and Equipment [Line Items]
Property, plant, and equipment estimated useful life	5 years
Maximum [Member] \| Machinery and Equipment [Member]
Property, Plant and Equipment [Line Items]
Property, plant, and equipment estimated useful life	11 years
Minimum [Member] \| Machinery and Equipment [Member]
Property, Plant and Equipment [Line Items]
Property, plant, and equipment estimated useful life	3 years

Inventories - Summary of Inventories (Detail) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Inventory Disclosure [Abstract]
Finished goods	$ 39,048	$ 42,281
Raw materials	44,475	31,686
Total FIFO inventories	83,523	73,967
Reserve to adjust inventories to LIFO value	(16,821)	(19,062)
Total LIFO inventories	$ 66,702	$ 54,905

Inventories - Additional Information (Detail) - USD ($)	12 Months Ended
Inventories - Additional Information (Detail) - USD ($)	Dec. 31, 2020	Dec. 31, 2019
Inventory Disclosure [Abstract]
LIFO inventory liquidations	$ 0	$ 0
Raw materials	$ 1,500,000	$ 1,200,000

Prepaid Expenses and Other Assets - Summary of Prepaid Expenses and Other Assets (Detail) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Prepaid Expense and Other Assets [Abstract]
Prepaid expenses	$ 7,285	$ 8,282
Revenues in excess of billings	6,612	6,664
Contract retainage	2,267	1,832
Income tax receivable	7,823	2,675
Other	1,323	350
Total prepaid expenses and other assets	$ 25,310	$ 19,803

Goodwill and Other Intangible Assets, Net - Additional Information (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Goodwill [Line Items]
Goodwill	$ 68.5
Amortization of intangible asset	0.4	$ 0.4	$ 3.1
Intangible Assets	6.3	6.3
Accumulated Amortization	1.1	0.7
Commercial [Member]
Goodwill [Line Items]
Goodwill		$ 54.3
Residential [Member]
Goodwill [Line Items]
Goodwill	$ 14.2
Domain Names [Member]
Goodwill [Line Items]
Amortization period	15 years

Property, Plant and Equipment - Summary of Property, Plant and Equipment (Detail) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Gross	$ 573,031	$ 393,812
Accumulated depreciation	(236,494)	(222,512)
Total property, plant and equipment, net	336,537	171,300
Machinery and Equipment [Member]
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Gross	312,870	248,633
Building and Improvements [Member]
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Gross	61,860	51,547
Forklifts and Tractors [Member]
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Gross	16,003	10,870
Computer Equipment and Software [Member]
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Gross	11,948	10,647
Furniture and Fixtures [Member]
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Gross	1,534	1,441
Construction in Process [Member]
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Gross	157,465	59,257
Land [Member]
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Gross	$ 11,351	$ 11,417

Property, Plant and Equipment - Additional Information (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Gross	$ 573,031	$ 393,812
Depreciation expense	17,500	13,600	$ 13,400
Construction in Process [Member]
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Gross	$ 157,465	$ 59,257

Accrued Expenses and Other Liabilities - Summary of Accrued Expenses and Other Liabilities (Detail) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Payables and Accruals [Abstract]
Sales and marketing	$ 22,938	$ 28,402
Compensation and benefits	21,156	13,475
Operating lease liabilities	$ 6,708	7,079
Operating lease liability current statement of financial position [Extensible List]	us-gaap:OperatingLeaseLiabilityCurrent
Manufacturing costs	$ 3,641	2,564
Customer deposits	1,174	2,905
Billings in excess of revenues	1,244	816
Other	5,470	3,024
Total accrued expenses and other liabilities	$ 62,331	$ 58,265

Debt - Schedule Of Debt (Detail)	12 Months Ended
Debt - Schedule Of Debt (Detail)	Dec. 31, 2020
Pricing Tier One [Member]
Line of Credit Facility [Line Items]
Consolidated Debt to Consolidated EBITDA Ratio	> 2.50:1.00
Revolving B Commitment Fee	0.60%
Pricing Tier Two [Member]
Line of Credit Facility [Line Items]
Consolidated Debt to Consolidated EBITDA Ratio	< 2.50:1.00 but > 2.00:1.00
Revolving B Commitment Fee	0.55%
Pricing Tier Three [Member]
Line of Credit Facility [Line Items]
Consolidated Debt to Consolidated EBITDA Ratio	< 2.00:1.00 but > 1.50:1.00
Revolving B Commitment Fee	0.50%
Pricing Tier Four [Member]
Line of Credit Facility [Line Items]
Consolidated Debt to Consolidated EBITDA Ratio	< 1.50:1.00
Revolving B Commitment Fee	0.45%
London Interbank Offered Rate (LIBOR) [Member] \| Pricing Tier One [Member]
Line of Credit Facility [Line Items]
Eurodollar Rate Loans / LIBOR Index	2.75%
London Interbank Offered Rate (LIBOR) [Member] \| Pricing Tier Two [Member]
Line of Credit Facility [Line Items]
Eurodollar Rate Loans / LIBOR Index	2.50%
London Interbank Offered Rate (LIBOR) [Member] \| Pricing Tier Three [Member]
Line of Credit Facility [Line Items]
Eurodollar Rate Loans / LIBOR Index	2.25%
London Interbank Offered Rate (LIBOR) [Member] \| Pricing Tier Four [Member]
Line of Credit Facility [Line Items]
Eurodollar Rate Loans / LIBOR Index	1.80%
Base Rate [Member] \| Pricing Tier One [Member]
Line of Credit Facility [Line Items]
Base Rate Loans	1.75%
Base Rate [Member] \| Pricing Tier Two [Member]
Line of Credit Facility [Line Items]
Base Rate Loans	1.50%
Base Rate [Member] \| Pricing Tier Three [Member]
Line of Credit Facility [Line Items]
Base Rate Loans	1.25%
Base Rate [Member] \| Pricing Tier Four [Member]
Line of Credit Facility [Line Items]
Base Rate Loans	0.80%

Debt - Additional Information (Detail) - USD ($)	May 26, 2020	Nov. 05, 2019	May 26, 2022	Dec. 31, 2020	Dec. 31, 2019
Line of Credit Facility [Line Items]
Company indebtedness				$ 0	$ 0
Remaining available borrowing capacity				300,000,000
Federal Funds Rate [Member]
Line of Credit Facility [Line Items]
Interest rate	0.50%
Eurodollar Rate Loans [Member]
Line of Credit Facility [Line Items]
Interest rate	1.00%
Fourth Amended And Restated Credit Agreement [Member]
Line of Credit Facility [Line Items]
Termination date of the Credit Agreement		Nov. 05, 2024
Revolver Loans Portion Effective January 1 through June 30 [Member] \| Fourth Amended And Restated Credit Agreement [Member]
Line of Credit Facility [Line Items]
Revolving loans in a collective maximum principal amount				250,000,000
Revolver Loans Portion Effective July 1 through December 31 [Member] \| Fourth Amended And Restated Credit Agreement [Member]
Line of Credit Facility [Line Items]
Revolving loans in a collective maximum principal amount				$ 200,000,000
Revolving Credit Facility [Member]
Line of Credit Facility [Line Items]
Line of Credit Facility, Additional Borrowing Capacity	$ 100,000,000		$ 100,000,000
Revolving Credit Facility [Member] \| BOA [Member]
Line of Credit Facility [Line Items]
Lender Percentage	47.50%
Revolving Credit Facility [Member] \| Well Fargo [Member]
Line of Credit Facility [Line Items]
Lender Percentage	28.00%
Revolving Credit Facility [Member] \| Regions [Member]
Line of Credit Facility [Line Items]
Lender Percentage	24.50%

Leases - Additional Information (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Weighted average discount rate	3.47%	3.66%
Operating lease cost	$ 8.5	$ 8.4
Weighted average remaining lease term	5 years 7 months 6 days	6 years 6 months

Leases - Supplemental Cash flow Information to operating leases (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Supplemental cash flow information
Cash paid for amounts included in the measurement of operating lease liabilities	$ 8,736	$ 8,479
Operating ROU assets obtained in exchange for lease liabilities	1,427	1,319
Supplemental balance sheet information
Operating lease ROU assets	34,382	40,049
Operating lease liabilities:
Accrued expenses and other current liabilities	6,708	7,079
Operating lease liabilities	28,579	34,242
Total operating lease liabilities	$ 35,287	$ 41,321

Leases - Maturities of Operating Lease Liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Operating Lease Liabilities, Payments Due [Abstract]
2021	$ 7,835
2022	7,345
2023	6,608
2024	6,265
2025	4,480
Thereafter	6,599
Total lease payments	39,132
Less imputed interest	(3,845)
Total operating liabilities	$ 35,287	$ 41,321

Stockholders' Equity - Additional Information (Detail) - $ / shares		12 Months Ended
	Sep. 14, 2020	Dec. 31, 2020	Jul. 29, 2020	Apr. 29, 2020	Feb. 19, 2020	Dec. 31, 2019
Equity, Class of Treasury Stock [Line Items]
Common stock, par value		$ 0.01	$ 0.01
Common stock, shares authorized		180,000,000		180,000,000	120,000,000	180,000,000
Description of stock split	two-for-one stock split
Stock Repurchase Programs [Member]
Equity, Class of Treasury Stock [Line Items]
Common stock repurchase program, authorized shares		11,600,000
Number of shares repurchased by the Company		2,800,000

Stockholders' Equity - Computation of Basic and Diluted Earnings Per Share (Detail) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2020	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Numerator:
Net income	$ 43,301	$ 42,710	$ 47,218	$ 42,402	$ 35,497	$ 41,976	$ 35,710	$ 31,555	$ 175,631	$ 144,738	$ 134,572
Denominator:
Basic weighted average shares outstanding	115,791,757	115,773,030	115,733,934	116,259,058	116,591,434	116,800,120	116,972,384	117,086,956	115,888,859	116,861,194	117,479,340
Effect of dilutive securities:
Diluted weighted average shares outstanding	116,169,754	116,134,623	116,061,988	116,647,442	117,025,466	117,209,206	117,375,080	117,658,354	116,252,866	117,315,498	118,134,604
Basic earnings per share	$ 0.37	$ 0.37	$ 0.41	$ 0.37	$ 0.31	$ 0.36	$ 0.31	$ 0.27	$ 1.52	$ 1.24	$ 1.15
Diluted earnings per share	$ 0.37	$ 0.37	$ 0.41	$ 0.37	$ 0.31	$ 0.36	$ 0.31	$ 0.27	$ 1.51	$ 1.24	$ 1.14
Stock appreciation rights [Member]
Effect of dilutive securities:
Dilutive securities									192,579	248,850	353,400
Restricted stock [Member]
Effect of dilutive securities:
Dilutive securities									171,428	205,454	301,864

Stockholders' Equity - Antidilutive Securities Excluded from Computation of Earnings Per Share (Detail) - shares	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Restricted stock [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Anti-dilutive securities excluded from the computation of diluted earnings per share	0	0	428
Stock appreciation rights [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Anti-dilutive securities excluded from the computation of diluted earnings per share	14,697	41,540	26,694

Revenue From Contracts With Customers - Additional Information (Detail) $ in Millions	12 Months Ended
	Dec. 31, 2020 USD ($)
Revenue from Contract with Customer [Abstract]
Revenue remaining performance obligation	$ 65.8
Revenue remaining performance obligation description	greater than one year

Revenue From Contracts With Customers - Summary of Disaggregated Net Sales (Detail) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2020	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Disaggregation of Revenue [Line Items]
Revenue from contract with customers	$ 228,286	$ 231,502	$ 220,648	$ 200,395	$ 164,772	$ 194,551	$ 206,453	$ 179,571	$ 880,831	$ 745,347	$ 684,250
Products Transferred at a Point in Time and Variable Consideration Contracts [Member]
Disaggregation of Revenue [Line Items]
Revenue from contract with customers									827,792	694,267	613,229
Products Transferred Over Time and Fixed Price Contracts [Member]
Disaggregation of Revenue [Line Items]
Revenue from contract with customers									53,039	51,080	71,021
Residential [Member]
Disaggregation of Revenue [Line Items]
Revenue from contract with customers									827,792	694,267	613,229
Residential [Member] \| Products Transferred at a Point in Time and Variable Consideration Contracts [Member]
Disaggregation of Revenue [Line Items]
Revenue from contract with customers									827,792	694,267	613,229
Commercial [Member]
Disaggregation of Revenue [Line Items]
Revenue from contract with customers									53,039	51,080	71,021
Commercial [Member] \| Products Transferred Over Time and Fixed Price Contracts [Member]
Disaggregation of Revenue [Line Items]
Revenue from contract with customers									$ 53,039	$ 51,080	$ 71,021

- Definition

Amount, excluding tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value added and excise.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
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-Section 50
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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-Subparagraph (a)
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Reference 4: http://www.xbrl.org/2003/role/disclosureRef
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-Name Accounting Standards Codification
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Reference 5: http://www.xbrl.org/2003/role/disclosureRef
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-Name Accounting Standards Codification
-Topic 280
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Reference 6: http://www.xbrl.org/2003/role/disclosureRef
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-Name Accounting Standards Codification
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Reference 7: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
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Reference 8: http://www.xbrl.org/2003/role/disclosureRef
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-Name Accounting Standards Codification
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Reference 9: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
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-URI http://asc.fasb.org/extlink&oid=120311839&loc=d3e9054-108599

Reference 10: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
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-URI http://asc.fasb.org/extlink&oid=121604090&loc=SL49130545-203045

Reference 11: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 924
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-URI http://asc.fasb.org/extlink&oid=6472922&loc=d3e499488-122856

+ Details

Stock-Based Compensation - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Approximate number of shares employees purchased under the Employee Stock Purchase Plan	1,811,165
2014 Stock Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total aggregate number of shares of common stock that may be issued	25,680,000
Number of common stock available for future issuance	11,253,930
Performance-Based Restricted Stock and Performance-Based Restricted Stock Units [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation cost recognition period for unvested awards	2 years
Unrecognized compensation cost related to unvested awards	$ 1.7	$ 0.8	$ 1.6
Vesting period	3 years
Stock Appreciation Rights [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation cost related to unvested awards	$ 0.6
Fair value assumptions method used	Black-Scholes option-pricing
Weighted-average fair value of grants	$ 17.81	$ 14.78	$ 11.05
Time-Based Restricted Stock and Time-Based Restricted Stock Units [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation cost related to unvested awards	$ 2.9
Total fair value of restricted shares vested	$ 6.1	$ 6.0	$ 5.1
Employee Stock Purchase Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total aggregate number of shares of common stock that may be issued	2,400,000
Percentage of market price on lesser of either first day of calendar quarter or last day of calendar quarter for purchase price	85.00%
Percentage of gross compensation eligible employees may elect to participate in the plan	15.00%
Maximum [Member] \| Performance-Based Restricted Stock and Performance-Based Restricted Stock Units [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of target number of shares that will vest	200.00%
Minimum [Member] \| Performance-Based Restricted Stock and Performance-Based Restricted Stock Units [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of target number of shares that will vest	0.00%

Stock-Based Compensation - Summary of Stock-Based Compensation Expenses (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense	$ 7,131	$ 6,930	$ 6,344
Stock Appreciation Rights [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense	648	662	370
Time-Based Restricted Stock and Restricted Stock Units [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense	3,219	3,676	2,687
Performance-Based Restricted Stock and Restricted Stock Units [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense	2,881	2,399	3,144
Employee Stock Purchase Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense	$ 383	$ 193	$ 143

Stock-Based Compensation - Time-Based Restricted Stock and Restricted Stock Unit Activity (Detail) - Time-Based Restricted Stock and Time-Based Restricted Stock Units [Member] - $ / shares	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Schedule Of Restricted Stock Activity [Line Items]
Nonvested, Shares, Beginning Balance	218,466	311,096	306,236
Time-based Restricted Stock, Granted	54,406	71,300	174,528
Time-based Restricted Stock, Vested	(111,036)	(162,650)	(169,100)
Time-based Restricted Stock, Forfeited	(1,114)	(1,280)	(568)
Nonvested, Shares, Ending Balance	160,722	218,466	311,096
Nonvested, Weighted-Average Grant Price Per Share, Beginning Balance	$ 28.75	$ 21.34	$ 13.45
Weighted-Average Grant Price Per Share, Granted	53.97	38.12	27.36
Weighted-Average Grant Price Per Share, Vested	30.94	18.67	13.33
Weighted-Average Grant Price Per Share, Forfeited	40.34	31.17	17.53
Nonvested, Weighted-Average Grant Price Per Share, Ending Balance	$ 35.68	$ 28.75	$ 21.34

Stock-Based Compensation - Performance-Based Restricted Stock Activity (Detail) - Performance-Based Restricted Stock and Performance-Based Restricted Stock Units [Member] - $ / shares	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Schedule Of Restricted Stock Activity [Line Items]
Nonvested, Shares, Beginning Balance	123,656	182,412	233,316
Performance-based Restricted Stock, Granted	78,404	164,270	161,140
Performance-based Restricted Stock, Vested	(128,762)	(222,004)	(212,044)
Performance-based Restricted Stock, Forfeited	(728)	(1,022)
Nonvested, Shares, Ending Balance	72,570	123,656	182,412
Nonvested, Weighted-Average Grant Price Per Share, Beginning Balance	$ 30.67	$ 18.43	$ 12.93
Weighted-Average Grant Price Per Share, Granted	39.60	23.82	17.63
Weighted-Average Grant Price Per Share, Vested	28.87	15.55	11.76
Weighted-Average Grant Price Per Share, Forfeited	41.12	29.23
Nonvested, Weighted-Average Grant Price Per Share, Ending Balance	$ 43.42	$ 30.67	$ 18.43

Stock-Based Compensation - Summary of Assumptions Used to Estimate Fair Value of Each SAR (Detail) - Stock Appreciation Rights [Member]	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Share Based Compensation Arrangement by Share Based Payment Award Fair Value Assumptions and Methodology [Line Items]
Dividend yield	0.00%	0.00%	0.00%
Average risk-free interest rate	1.30%	2.50%	2.70%
Expected term (years)	5 years	5 years	5 years
Expected volatility	38.30%	39.10%	40.50%

Stock-Based Compensation - SAR Activity (Detail) - Stock Appreciation Rights [Member] - USD ($)	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Schedule Of Stock Appreciation Rights Activity [Line Items]
SARs Outstanding, Beginning Balance	304,038	476,952	556,232
Granted, SARs	43,830	49,072	42,520
Exercised, SARs	(54,592)	(217,528)	(121,800)
Canceled, SARs		(4,458)
Shares Outstanding, SARs, Ending Balance	293,276	304,038	476,952
Outstanding, Weighted Average Grant Price Per Share, Beginning Balance	$ 15.79	$ 9.63	$ 6.73
Vested, SARs	237,323
Granted, Weighted Average Grant Price Per Share	$ 50.39	38.85	28.30
Exercisable, SARs	237,323
Exercised, Weighted Average Grant Price Per Share	$ 9.41	6.95	2.64
Canceled, Weighted Average Grant Price Per Share		38.85
Outstanding, Weighted Average Grant Price Per Share, Ending Balance	22.15	$ 15.79	$ 9.63
Vested, Weighted Average Grant Price Per Share	17.05
Exercisable, Weighted Average Grant Price Per Share	$ 17.05
Weighted Average Remaining Contractual Life, Outstanding	5 years 4 months 24 days
Weighted Average Remaining Contractual Life, Vested	4 years 8 months 12 days
Weighted Average Remaining Contractual Life, Exercisable	4 years 8 months 12 days
Aggregate Intrinsic Value, Outstanding	$ 18,058,138
Aggregate Intrinsic Value, Vested	15,821,712
Aggregate Intrinsic Value, Exercisable	$ 15,821,712

Employee Benefit Plans - Additional Information (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Defined Benefit Plan Disclosure [Line Items]
Employer's contribution	$ 5.7	$ 4.6	$ 4.2

Income Taxes - Income Tax Provision (Benefit) (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Current income tax provision:
Federal	$ 35,423	$ 30,306	$ 33,578
State	10,455	6,952	7,674
Total	45,878	37,258	41,252
Deferred income tax provision:
Federal	12,603	6,928	988
State	522	778	49
Total	13,125	7,706	1,037
Total income tax provision	$ 59,003	$ 44,964	$ 42,289

- Definition

Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

+ References + Details

Income Taxes - Reconciliation of Differences between Income Tax Provision and Income Tax Determined by Applying US Federal Statutory Rate (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Effective Income Tax Rate Reconciliation, Amount [Abstract]
U.S. Federal statutory taxes	$ 49,273	$ 39,838	$ 37,141
State and local taxes, net of U.S. Federal benefit	10,641	8,412	7,716
Permanent items	1,198	1,266	470
Excess tax benefits from vesting or settlement of stock compensation awards	(1,635)	(3,540)	(2,368)
Federal credits	(565)	(654)	(662)
Other	91	(358)	(8)
Total income tax provision	$ 59,003	$ 44,964	$ 42,289

- Definition

Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

+ References + Details

Income Taxes - Schedule of Deferred Tax Assets and Liabilities (Detail) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Deferred tax assets:
Net operating losses	$ 43	$ 88
Residential product warranty reserve	7,532	6,486
Stock-based compensation	1,071	1,055
Accruals not currently deductible and other	2,041	2,245
Inventories	5,548	5,780
Operating lease liability	9,081	10,618
State tax credit carryforwards	3,345	3,461
Gross deferred tax assets, before valuation allowance	28,661	29,733
Valuation allowance	(2,775)	(2,988)
Gross deferred tax assets, after valuation allowance	25,886	26,745
Deferred tax liabilities:
Depreciation	(29,792)	(17,267)
Operating lease right-of-use asset	(8,755)	(10,162)
Goodwill amortization	(5,775)	(4,782)
Inventories and other	(4,520)	(4,365)
Gross deferred tax liabilities	(48,842)	(36,576)
Net deferred tax liability	$ (22,956)	$ (9,831)

Income Taxes - Additional Information (Detail)	12 Months Ended
Income Taxes - Additional Information (Detail)	Dec. 31, 2020 USD ($) Tax_Positions	Dec. 31, 2019 USD ($)
Income Tax Contingency [Line Items]
Valuation allowance	$ 2,775,000	$ 2,988,000
Unrecognized tax benefits number of tax matters \| Tax_Positions	0
Unrecognized tax benefits related to identified uncertain tax positions	$ 0
Tax years subject to examination	2016 2017 2018

Segment Information - Additional Information (Detail)	12 Months Ended
Segment Information - Additional Information (Detail)	Dec. 31, 2020 Segment Retailer
Segment Reporting Information [Line Items]
Number of reportable segment \| Segment	2
Number of national retailers \| Retailer	2

Segment Information - Details of Segment Information (Detail) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2020	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Segment Reporting Information [Line Items]
Net Sales	$ 228,286	$ 231,502	$ 220,648	$ 200,395	$ 164,772	$ 194,551	$ 206,453	$ 179,571	$ 880,831	$ 745,347	$ 684,250
Net Income	43,301	$ 42,710	$ 47,218	$ 42,402	35,497	$ 41,976	$ 35,710	$ 31,555	175,631	144,738	134,572
Depreciation and amortization									17,939	14,031	16,597
Income Tax Expense									59,003	44,964	42,289
Total Assets	770,492				592,239				770,492	592,239
Residential [Member]
Segment Reporting Information [Line Items]
Net Sales									827,792	694,267	613,229
Commercial [Member]
Segment Reporting Information [Line Items]
Net Sales									53,039	51,080	71,021
Operating Segments [Member]
Segment Reporting Information [Line Items]
Net Sales									880,831	745,347	684,250
Net Income									175,631	144,738	134,572
EBITDA									251,575	202,230	193,136
Depreciation and amortization									17,940	14,031	16,467
Income Tax Expense									59,003	44,964	42,289
Capital Expenditures									172,823	67,265	33,816
Total Assets	770,492				592,239				770,492	592,239	465,122
Operating Segments [Member] \| Residential [Member]
Segment Reporting Information [Line Items]
Net Sales									827,792	694,267	613,229
Net Income									171,197	142,811	131,823
EBITDA									244,817	199,020	186,268
Depreciation and amortization									17,131	13,413	13,216
Income Tax Expense									57,488	44,292	41,421
Capital Expenditures									171,784	65,399	31,392
Total Assets	676,948				503,883				676,948	503,883	380,682
Operating Segments [Member] \| Commercial [Member]
Segment Reporting Information [Line Items]
Net Sales									53,039	51,080	71,021
Net Income									4,434	1,927	2,749
EBITDA									6,758	3,210	6,868
Depreciation and amortization									809	618	3,251
Income Tax Expense									1,515	672	868
Capital Expenditures									1,039	1,866	2,424
Total Assets	$ 93,544				$ 88,356				$ 93,544	$ 88,356	$ 84,440

Segment Information - Schedule of Reconciliation of Net Income to EBITDA (Detail) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2020	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Segment Reporting Information [Line Items]
Net Income	$ 43,301	$ 42,710	$ 47,218	$ 42,402	$ 35,497	$ 41,976	$ 35,710	$ 31,555	$ 175,631	$ 144,738	$ 134,572
Interest (income) expense, net									(999)	(1,503)	(192)
Income Tax Expense									59,003	44,964	42,289
Depreciation and Amortization									17,939	14,031	16,597
Operating Segments [Member]
Segment Reporting Information [Line Items]
Net Income									175,631	144,738	134,572
Interest (income) expense, net									(999)	(1,503)	(192)
Income Tax Expense									59,003	44,964	42,289
Depreciation and Amortization									17,940	14,031	16,467
EBITDA									251,575	202,230	193,136
Operating Segments [Member] \| Residential [Member]
Segment Reporting Information [Line Items]
Net Income									171,197	142,811	131,823
Interest (income) expense, net									(999)	(1,496)	(192)
Income Tax Expense									57,488	44,292	41,421
Depreciation and Amortization									17,131	13,413	13,216
EBITDA									244,817	199,020	186,268
Operating Segments [Member] \| Commercial [Member]
Segment Reporting Information [Line Items]
Net Income									4,434	1,927	2,749
Interest (income) expense, net									0	(7)	0
Income Tax Expense									1,515	672	868
Depreciation and Amortization									809	618	3,251
EBITDA									$ 6,758	$ 3,210	$ 6,868

- Definition

Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

+ References + Details

- Definition

The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

+ References

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+ Details

Commitments and Contingencies - Additional Information (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Schedule Of Commitments And Contingencies [Line Items]
Change in warranty reserve for disclosure purposes only	$ 2,100
Surface Flaking [Member]
Schedule Of Commitments And Contingencies [Line Items]
Provisions and changes in estimates for the future settlement of surface flaking claims	$ 6,500
Minimum [Member]
Schedule Of Commitments And Contingencies [Line Items]
Average period for PE material purchases under short-term supply contracts for which pricing is negotiated as needed	1 year
Maximum [Member]
Schedule Of Commitments And Contingencies [Line Items]
Average period for PE material purchases under short-term supply contracts for which pricing is negotiated as needed	2 years
Surface Flaking Warranty Reserve [Member]
Schedule Of Commitments And Contingencies [Line Items]
Percentage change in warranty claims used as a threshold for disclosure	10.00%
Provisions and changes in estimates for the future settlement of surface flaking claims	$ 9,861	$ 979
Surface Flaking Warranty Reserve [Member] \| Surface Flaking [Member]
Schedule Of Commitments And Contingencies [Line Items]
Provisions and changes in estimates for the future settlement of surface flaking claims	$ 6,479	$ 0
Residential Use [Member]
Schedule Of Commitments And Contingencies [Line Items]
Warranty period	25 years
Commercial Use [Member]
Schedule Of Commitments And Contingencies [Line Items]
Warranty period	10 years
Transcend Enhance Select And Universal Fascia Product [Member] \| Residential Use [Member]
Schedule Of Commitments And Contingencies [Line Items]
Warranty period	25 years
Transcend Enhance Select And Universal Fascia Product [Member] \| Commercial Use [Member]
Schedule Of Commitments And Contingencies [Line Items]
Warranty period	10 years
Trex Signature Railing [Member] \| Residential Use [Member]
Schedule Of Commitments And Contingencies [Line Items]
Warranty period	25 years
Trex Signature Railing [Member] \| Commercial Use [Member]
Schedule Of Commitments And Contingencies [Line Items]
Warranty period	25 years
Commercial Railing And Staging Systems [Member] \| Commercial Use [Member] \| Minimum [Member]
Schedule Of Commitments And Contingencies [Line Items]
Warranty period	1 year
Commercial Railing And Staging Systems [Member] \| Commercial Use [Member] \| Maximum [Member]
Schedule Of Commitments And Contingencies [Line Items]
Warranty period	3 years
Raw Material Supply Contracts [Member]
Schedule Of Commitments And Contingencies [Line Items]
Purchase commitment	$ 33,600
Purchase commitment, due in second year	15,000
Purchase commitment, due in third year	22,700
Purchase commitment, due in fourth year	$ 22,700

Commitments and Contingencies - Summary of Reconciliation of Company's Residential Product Warranty Reserve (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Surface Flaking Warranty Reserve [Member]
Product Warranty Liability [Line Items]
Beginning balance	$ 25,494	$ 30,754
Provisions and changes in estimates	9,861	979
Settlements made during the period	(5,882)	(6,239)
Ending balance	29,473	25,494
Surface Flaking [Member]
Product Warranty Liability [Line Items]
Provisions and changes in estimates	6,500
Surface Flaking [Member] \| Surface Flaking Warranty Reserve [Member]
Product Warranty Liability [Line Items]
Beginning balance	19,024	23,951
Provisions and changes in estimates	6,479	0
Settlements made during the period	(4,178)	(4,927)
Ending balance	21,325	19,024
Other Residential [Member] \| Surface Flaking Warranty Reserve [Member]
Product Warranty Liability [Line Items]
Beginning balance	6,470	6,803
Provisions and changes in estimates	3,382	979
Settlements made during the period	(1,704)	(1,312)
Ending balance	$ 8,148	$ 6,470

Interim Financial Data (Unaudited) - Summary of Interim Financial Data (Detail) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2020	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Quarterly Financial Data [Abstract]
Net sales	$ 228,286	$ 231,502	$ 220,648	$ 200,395	$ 164,772	$ 194,551	$ 206,453	$ 179,571	$ 880,831	$ 745,347	$ 684,250
Gross profit	92,392	84,964	92,405	89,696	71,263	82,431	83,444	69,365	359,457	306,503	294,894
Net income	$ 43,301	$ 42,710	$ 47,218	$ 42,402	$ 35,497	$ 41,976	$ 35,710	$ 31,555	$ 175,631	$ 144,738	$ 134,572
Basic earnings per common share	$ 0.37	$ 0.37	$ 0.41	$ 0.37	$ 0.31	$ 0.36	$ 0.31	$ 0.27	$ 1.52	$ 1.24	$ 1.15
Basic weighted average common shares outstanding	115,791,757	115,773,030	115,733,934	116,259,058	116,591,434	116,800,120	116,972,384	117,086,956	115,888,859	116,861,194	117,479,340
Diluted earnings per common share	$ 0.37	$ 0.37	$ 0.41	$ 0.37	$ 0.31	$ 0.36	$ 0.31	$ 0.27	$ 1.51	$ 1.24	$ 1.14
Diluted weighted average common shares outstanding	116,169,754	116,134,623	116,061,988	116,647,442	117,025,466	117,209,206	117,375,080	117,658,354	116,252,866	117,315,498	118,134,604

- Definition

The amount of net income (loss) for the period per each share of common stock or unit outstanding during the reporting period.

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- Definition

The amount of net income (loss) for the period available to each share of common stock or common unit outstanding during the reporting period and to each share or unit that would have been outstanding assuming the issuance of common shares or units for all dilutive potential common shares or units outstanding during the reporting period.

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Aggregate revenue less cost of goods and services sold or operating expenses directly attributable to the revenue generation activity.

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The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

Interim Financial Data (Unaudited) - Additional Information (Detail)	Jul. 29, 2020
Quarterly Financial Data [Abstract]
Stock split	2

Schedule II - Valuation and Qualifying Accounts and Reserves (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Warranty Reserve [Member]
SEC Schedule, 12-09, Valuation and Qualifying Accounts Disclosure [Line Items]
Balance at Beginning of Period	$ 25,494	$ 30,754	$ 34,999
Additions (Reductions) Charged to Cost and Expenses	9,861	979	1,104
Deductions	(5,882)	(6,239)	(5,349)
Balance at End of Period	29,473	25,494	30,754
Valuation Allowance of Deferred Tax Assets [Member]
SEC Schedule, 12-09, Valuation and Qualifying Accounts Disclosure [Line Items]
Balance at Beginning of Period	2,988	3,015	3,096
Additions (Reductions) Charged to Cost and Expenses	1
Deductions	(214)	(27)	(81)
Balance at End of Period	$ 2,775	$ 2,988	$ 3,015