Segment and Geographical Information - Schedule of Long Lived Assets by Geographical Areas (Detail) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2012	Dec. 31, 2011
Revenues from External Customers and Long-Lived Assets [Line Items]
Total consolidated assets	$ 382,127	$ 366,692
United States [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Total consolidated assets	213,912	198,578
International [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Total consolidated assets	$ 168,215	$ 168,114