Certain Balance Sheet Accounts - Summary of Property and Equipment (Detail) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012
Property, Plant and Equipment [Line Items]
Total property and equipment	$ 75,692	$ 74,057
Less accumulated depreciation and amortization	35,824	27,757
Property and equipment, net	39,868	46,300
Computers and Equipment [Member]
Property, Plant and Equipment [Line Items]
Total property and equipment	18,446	17,614
Computer Software [Member]
Property, Plant and Equipment [Line Items]
Total property and equipment	22,315	22,242
Furniture and Fixtures [Member]
Property, Plant and Equipment [Line Items]
Total property and equipment	8,902	8,561
Leasehold Improvements [Member]
Property, Plant and Equipment [Line Items]
Total property and equipment	$ 26,029	$ 25,640