Licenses - Additional Information (Detail) (USD $) In Thousands, unless otherwise specified	1 Months Ended	12 Months Ended
	Nov. 09, 2012	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Licenses Agreements [Line Items]
Payment of royalty obligation	$ 816
Second payment for royalty obligation		1,611
Royalty expense under license agreement		$ 3,079	$ 1,698	$ 1,631