Summary of Significant Accounting Policies - Reconciliation of Reserve for Warranty Expense (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Movement in Standard and Extended Product Warranty Accrual, Increase (Decrease) [Roll Forward]
Beginning balance	$ 5,706	$ 5,607	$ 6,406
Provision	5,493	5,220	4,724
Claims paid/costs incurred	(5,804)	(5,121)	(5,523)
Ending balance	$ 5,395	$ 5,706	$ 5,607