Reserves and Related Activities for 2008 Product Recall (Detail) (2008 Product recall, Warranty Reserves [Member], USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2011
Product Liability Contingency [Line Items]
Beginning balance	$ 2,893
Changes in Estimates	(236)
Reserves Used	(2,778)
Ending balance	(121)
Excise tax credit
Product Liability Contingency [Line Items]
Beginning balance	(158)
Changes in Estimates	(348)
Reserves Used	264
Ending balance	(242)
Recall-related costs
Product Liability Contingency [Line Items]
Beginning balance	255
Changes in Estimates	105
Reserves Used	(306)
Ending balance	54
Inventory resreves
Product Liability Contingency [Line Items]
Beginning balance	2,796
Changes in Estimates	7
Reserves Used	(2,736)
Ending balance	$ 67