Summary of Significant Accounting Policies - Additional Information (Detail) (USD $)	12 Months Ended									3 Months Ended	12 Months Ended		0 Months Ended	12 Months Ended
	Dec. 31, 2013 Customer Supplier Institution	Dec. 31, 2012 Customer	Dec. 31, 2011 Customer	Dec. 31, 2010	Dec. 31, 2013 Commercial Use [Member]	Dec. 31, 2013 Residential Use [Member]	Dec. 31, 2013 Trex Trim Trex Reveal Railing [Member] Residential and Commercial Use [Member]	Dec. 31, 2013 Transcend, Enhance, Select and Universal Fascia Product [Member] Commercial Use [Member]	Dec. 31, 2013 Transcend, Enhance, Select and Universal Fascia Product [Member] Residential Use [Member]	Sep. 30, 2013 Contract Termination [Member]	Dec. 31, 2013 Contract Termination [Member] sqft	Dec. 31, 2013 Sublease [Member] sqft	May 02, 2011 Iron Deck Acquisition [Member]	Dec. 31, 2013 Iron Deck Acquisition [Member]	Dec. 31, 2012 Iron Deck Acquisition [Member]	Dec. 31, 2013 Customer Concentration Risk [Member] Customer One [Member]	Dec. 31, 2012 Customer Concentration Risk [Member] Customer One [Member]	Dec. 31, 2011 Customer Concentration Risk [Member] Customer One [Member]	Dec. 31, 2012 Customer Concentration Risk [Member] Customer Two [Member]	Dec. 31, 2013 Customer Concentration Risk [Member] Minimum [Member]	Dec. 31, 2012 Customer Concentration Risk [Member] Minimum [Member]	Dec. 31, 2011 Customer Concentration Risk [Member] Minimum [Member]	Dec. 31, 2013 Credit Concentration Risk [Member] Customer One [Member]	Dec. 31, 2013 Credit Concentration Risk [Member] Customer Two [Member]	Dec. 31, 2013 Credit Concentration Risk [Member] Customer Three [Member]	Dec. 31, 2013 Supplier Concentration Risk [Member]	Dec. 31, 2012 Supplier Concentration Risk [Member]	Dec. 31, 2011 Supplier Concentration Risk [Member]
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
Cash paid for acquisition													2,000,000
Goodwill	10,500,000												3,700,000
Reduction in provision for future contingent payments														200,000	1,400,000
Maximum term of original maturities to classify as cash equivalent	3 months
Number of financial institutions where deposits are maintained	1
Concentration risk as percentage of total																28.00%	26.00%	24.00%	10.00%	10.00%	10.00%	10.00%	29.00%	15.00%	12.00%	44.00%	40.00%	33.00%
Number of customers that accounted for 10% or more of net sales	1	2	1
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	24,497,000	23,719,000
Expiration date of reconsidered corporate headquarters lease											Jun. 30, 2019
Lease square feet											55,047	41,701
Charge recorded due to revised estimate of sublease receipts	1,144,000	727,000								1,100,000
Annual impairment test of goodwill	0	0	0
Warranty period					10 years	25 years	25 years	10 years	25 years
Research and Development costs	2,900,000	2,900,000	2,500,000
Prepaid expenses for production costs of advertising	500,000	600,000
Branding Expenses	$ 20,900,000	$ 20,500,000	$ 19,400,000