Warranty Costs - Changes in Carrying Amount of Accrued Product Warranty Costs (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Movement in Liabilities for Guarantees on Long-Duration Contracts, Guaranteed Benefit Liability, Gross [Roll Forward]
Balance at beginning of period	$ 7,479	$ 9,158	$ 9,468
Accrued current period warranty expense	2,365	1,057	1,355
Acquired warranty reserve	6,621		1,636
Payments and adjustments	(7,042)	(2,736)	(3,301)
Balance at end of period	$ 9,423	$ 7,479	$ 9,158