Summary of Significant Accounting Policies - Property and Equipment, Net Estimated Useful Lives (Detail)	12 Months Ended
	Dec. 31, 2013
Computer Equipment And Software [Member] | Minimum [Member]
Property and equipment estimated useful lives
Property and Equipment useful lives	3 years
Computer Equipment And Software [Member] | Maximum [Member]
Property and equipment estimated useful lives
Property and Equipment useful lives	5 years
Furniture and Fixtures [Member] | Minimum [Member]
Property and equipment estimated useful lives
Property and Equipment useful lives	3 years
Furniture and Fixtures [Member] | Maximum [Member]
Property and equipment estimated useful lives
Property and Equipment useful lives	5 years
Leasehold Improvements [Member]
Property and equipment estimated useful lives
Property and Equipment useful lives	shorter of the lease term or estimated useful life