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Summary of Significant Accounting Policies - Additional Information (Detail) (USD $)	0 Months Ended	12 Months Ended
	May 07, 2014	Dec. 31, 2014 Supplier Institution Customer	Dec. 31, 2013 Customer	Dec. 31, 2012 Customer	Dec. 31, 2010	May 07, 2014	Apr. 30, 2014	Feb. 28, 2014
Schedule Of Significant Accounting Policies [Line Items]
Holding company's interest in Denplax		35.00%
Charge to earning to fully reserve the equity investment and note					$ 2,400,000
Stock split description		Each stockholder to receive one additional share of common stock, par value $0.01, 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 related notes are presented on a post-split basis.
Common stock, par value	$ 0.01	$ 0.01	$ 0.01			$ 0.01		$ 0.01
Stock split conversion ratio	2
Number of authorized shares of common stock		80,000,000us-gaap_CommonStockSharesAuthorized	80,000,000us-gaap_CommonStockSharesAuthorized				80,000,000us-gaap_CommonStockSharesAuthorized
Maximum term of original maturities to classify as cash equivalent		3 months
Number of financial institutions where deposits are maintained		1
Number of customers that accounted for 10% or more of net sales		1	1	2
Number of customer accounted for 10% or more account receivable		3
Number of largest raw material suppliers		4
Excess of the replacement cost of inventory over the LIFO value of inventory		25,299,000us-gaap_InventoryLIFOReserve	24,497,000us-gaap_InventoryLIFOReserve
Charge recorded		1,471,000us-gaap_RestructuringCharges	1,144,000us-gaap_RestructuringCharges
Annual impairment test of goodwill		0us-gaap_GoodwillImpairmentLoss	0us-gaap_GoodwillImpairmentLoss	0us-gaap_GoodwillImpairmentLoss
Goodwill		10,500,000us-gaap_Goodwill
Valuation allowance		4,465,000	4,201,000
Research and Development costs		2,300,000us-gaap_ResearchAndDevelopmentExpense	2,900,000us-gaap_ResearchAndDevelopmentExpense	2,900,000us-gaap_ResearchAndDevelopmentExpense
Prepaid expenses for production costs of advertising		500,000us-gaap_PrepaidAdvertising	500,000us-gaap_PrepaidAdvertising
Branding Expenses		20,800,000us-gaap_AdvertisingExpense	20,900,000us-gaap_AdvertisingExpense	20,500,000us-gaap_AdvertisingExpense
Scenario, Previously Reported [Member]
Schedule Of Significant Accounting Policies [Line Items]
Number of authorized shares of common stock							40,000,000
Contract Termination [Member]
Schedule Of Significant Accounting Policies [Line Items]
Expiration date of reconsidered corporate headquarters lease		Jun. 30, 2019
Lease square feet		55,047
Charge recorded		$ 1,471,000	$ 1,144,000
Sublease [Member]
Schedule Of Significant Accounting Policies [Line Items]
Lease square feet		24,732
Residential Use [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
TrexTrim and Trex Reveal Railing [Member] \| Residential Use [Member]
Schedule Of Significant Accounting Policies [Line Items]
Warranty period		25 years
TrexTrim and Trex Reveal Railing [Member] \| Commercial Use [Member]
Schedule Of Significant Accounting Policies [Line Items]
Warranty period		25 years
Transcend, Enhance, Select and Universal Fascia Product [Member] \| Residential Use [Member]
Schedule Of Significant Accounting Policies [Line Items]
Warranty period		25 years
Transcend, Enhance, Select and Universal Fascia Product [Member] \| Commercial Use [Member]
Schedule Of Significant Accounting Policies [Line Items]
Warranty period		10 years
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		24.00%	28.00%	26.00%
Sales Revenue, Net [Member] \| Customer Concentration Risk [Member] \| Customer Two [Member]
Schedule Of Significant Accounting Policies [Line Items]
Concentration risk as percentage of total				10.00%
Accounts Receivable [Member] \| Customer Concentration Risk [Member] \| Customer One [Member]
Schedule Of Significant Accounting Policies [Line Items]
Concentration risk as percentage of total		28.00%
Accounts Receivable [Member] \| Customer Concentration Risk [Member] \| Customer Two [Member]
Schedule Of Significant Accounting Policies [Line Items]
Concentration risk as percentage of total		13.00%
Accounts Receivable [Member] \| Customer Concentration Risk [Member] \| Customer Three [Member]
Schedule Of Significant Accounting Policies [Line Items]
Concentration risk as percentage of total		11.00%
Raw Materials [Member] \| Supplier Concentration Risk [Member]
Schedule Of Significant Accounting Policies [Line Items]
Concentration risk as percentage of total		38.00%	44.00%	40.00%