Product Warranty Accrual Included in Other Accrued Liabilities (Detail) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014
Other Accrued Liabilities [Line Items]
Balance as of January 1	$ 15,462	$ 14,719
Provision for warranties issued in current year	5,578	4,975
Recovery of pre-existing warranties	(289)	(112)
Payments	(3,764)	(4,097)
Balance as of September 30	$ 16,987	$ 15,485