Acquisition - Additional Information (Detail) - USD ($) $ in Thousands			3 Months Ended								5 Months Ended	12 Months Ended
	Aug. 17, 2017	Jul. 31, 2017	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2017	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Business Acquisition [Line Items]
Fund used to acquire business from revolving credit facility			$ 0				$ 0				$ 0	$ 0	$ 0
Repayment of revolving credit facility												201,000	249,700	$ 218,500
Goodwill			68,461				10,523				68,461	68,461	10,523
Net sales			122,212	$ 140,194	$ 157,941	$ 144,806	95,322	$ 106,168	$ 146,450	$ 131,676		565,153	479,616	440,804
Net income (loss)			18,299	$ 20,098	$ 28,782	$ 27,949	$ 12,629	$ 7,787	$ 23,725	$ 23,706		95,128	$ 67,847	$ 48,098
Acquisition-related expenses												$ 500
Blended statutory rate												38.00%
Trex Commercial Products, Inc. (TCP) [Member]
Business Acquisition [Line Items]
Net sales											21,800
Net income (loss)											(2,300)
Staging Concepts Acquisition, LLC [Member]
Business Acquisition [Line Items]
Certain assets and liabilities acquired in cash		$ 71,800
Estimated consideration			71,804								71,804	$ 71,804
Goodwill			57,938								57,938	57,938
Goodwill expected to be amortized and deductible for tax purposes			$ 1,600								$ 1,600	$ 1,600
Amortization period for intangible assets												12 months
Staging Concepts Acquisition, LLC [Member] | Revolving Credit Facility [Member]
Business Acquisition [Line Items]
Fund used to acquire business from revolving credit facility		$ 30,000
Repayment of revolving credit facility	$ 30,000