Valuation and Qualifying Accounts and Reserves (Detail) (Allowance for inventory reserves [Member], USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Allowance for inventory reserves [Member]
Valuation and Qualifying Accounts Disclosure [Line Items]
Balance at Beginning of Year	$ 2,439	$ 3,982	$ 3,336
Charged to Costs and Expenses, Net of Reversals	1,225	2,766	1,012
Utilizations	(2,716)	(4,309)	(366)
Balance at End of Year	$ 948	$ 2,439	$ 3,982