Schedule II - Valuation and Qualifying Accounts (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Allowance for Doubtful Accounts [Member]
Valuation and Qualifying Accounts Disclosure [Line Items]
Balance at Beginning of period	$ 200	$ 450	$ 200
Charged to Costs and Expenses	24	(242)	296
Charged to Other Accounts
Deductions	(24)	(8)	(46)
Balance at End of Period	200	200	450
Allowance for Excess and Obsolete Inventory [Member]
Valuation and Qualifying Accounts Disclosure [Line Items]
Balance at Beginning of period	2,320	4,431	351
Charged to Costs and Expenses	595	554	4,610
Charged to Other Accounts
Deductions	(1,916)	(2,665)	(530)
Balance at End of Period	999	2,320	4,431
Warranty Reserve [Member]
Valuation and Qualifying Accounts Disclosure [Line Items]
Balance at Beginning of period	484	427	646
Charged to Costs and Expenses	1,001	527	310
Charged to Other Accounts
Deductions	(530)	(470)	(529)
Balance at End of Period	$ 955	$ 484	$ 427