Property and Equipment, Net - Components of Company's Property and Equipment (Detail) - USD ($)
$ in Thousands
Dec. 31, 2015
Dec. 31, 2014
Property, Plant and Equipment [Line Items]    
Property and equipment, gross $ 85,465 $ 93,374
Accumulated depreciation (48,967) (62,957)
Property and equipment, net 36,498 30,417
Leasehold Improvements [Member]    
Property, Plant and Equipment [Line Items]    
Property and equipment, gross 40,583 43,930
Office Furniture, Fixtures and Equipment [Member]    
Property, Plant and Equipment [Line Items]    
Property and equipment, gross 16,234 18,693
Computer Equipment and Software [Member]    
Property, Plant and Equipment [Line Items]    
Property and equipment, gross $ 28,648 $ 30,751