Warranty Accrual - Warranty Accrual Activity (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2012	Sep. 30, 2011
Product Liability Contingency [Line Items]
Beginning Balance	$ 24,036	$ 31,200	$ 25,525	$ 34,704
Expense provisions	1,479	1,265	3,122	3,140
Cash payments	(2,433)	(2,707)	(5,565)	(5,823)
Adjustments		(955)		(3,218)
Ending Balance	$ 23,082	$ 28,803	$ 23,082	$ 28,803