Business and Significant Accounting Policies (Detail) - Property, Equipment and Leasehold Improvements, Less Accumulated Depreciation and Amortization - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014
Property, Plant and Equipment [Line Items]
Property, equipment and Leasehold Improvements, gross	$ 274,370	$ 259,608
Less — accumulated depreciation and amortization	(165,637)	(161,618)
Property, equipment and leasehold improvements, net	108,733	97,990
Software
Property, Plant and Equipment [Line Items]
Property, equipment and Leasehold Improvements, gross	$ 148,195	144,293
Software | Minimum
Property, Plant and Equipment [Line Items]
Useful Life	2 years
Software | Maximum
Property, Plant and Equipment [Line Items]
Useful Life	7 years
Furniture and equipment
Property, Plant and Equipment [Line Items]
Property, equipment and Leasehold Improvements, gross	$ 39,072	37,221
Furniture and equipment | Minimum
Property, Plant and Equipment [Line Items]
Useful Life	3 years
Furniture and equipment | Maximum
Property, Plant and Equipment [Line Items]
Useful Life	8 years
Leasehold improvements
Property, Plant and Equipment [Line Items]
Property, equipment and Leasehold Improvements, gross	$ 87,103	$ 78,094
Leasehold improvements | Minimum
Property, Plant and Equipment [Line Items]
Useful Life	2 years
Leasehold improvements | Maximum
Property, Plant and Equipment [Line Items]
Useful Life	15 years