Property and Equipment by Geographic Area (Detail) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Revenues from External Customers and Long-Lived Assets [Line Items]
Total property and equipment	$ 64,643	$ 60,538
UNITED STATES
Revenues from External Customers and Long-Lived Assets [Line Items]
Total property and equipment	49,957	45,116
India
Revenues from External Customers and Long-Lived Assets [Line Items]
Total property and equipment	3,123	3,226
Europe
Revenues from External Customers and Long-Lived Assets [Line Items]
Total property and equipment	7,840	9,095
Other International
Revenues from External Customers and Long-Lived Assets [Line Items]
Total property and equipment	$ 3,723	$ 3,101