Property and Equipment, Net (Detail) (USD $) In Thousands, unless otherwise specified	Jun. 30, 2013	Dec. 31, 2012
Property, Plant and Equipment [Line Items]
Capitalized software costs	$ 189,670	$ 186,538
Furniture and equipment	22,641	24,359
Leasehold improvements	40,610	45,184
Computer and communications equipment	184,556	191,377
Property, Plant and Equipment, Gross, Total	437,477	447,458
Less: accumulated depreciation	305,084	299,845
Property and equipment, net	$ 132,393	$ 147,613