Product Warranties - Summary of Changes in Product Warranties Reserve (Detail) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Product Warranties Disclosures [Abstract]
Warranty reserve, beginning of period	$ 89,743	$ 98,765	$ 94,060	$ 101,507
Provision	11,144	13,193	20,226	23,453
Payments	(15,013)	(14,768)	(28,412)	(27,770)
Warranty reserve, end of period	$ 85,874	$ 97,190	$ 85,874	$ 97,190