Capitalized Software, Furniture, Equipment and Leasehold Improvements - Capitalized Software Development Costs, Furniture, Equipment and Leasehold Improvements, Net of Accumulated Depreciation and Amortization (Detail) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012
Property, Plant and Equipment [Line Items]
Accumulated depreciation and amortization	$ (44,115)	$ (37,907)
Total capitalized software, furniture, equipment and leasehold improvements, net of accumulated depreciation and amortization	32,703	18,009
Software Development Costs [Member]
Property, Plant and Equipment [Line Items]
Total capitalized software, furniture, equipment and leasehold improvements, net of accumulated depreciation and amortization	41,062	30,482
Computer Hardware and Related Software [Member]
Property, Plant and Equipment [Line Items]
Total capitalized software, furniture, equipment and leasehold improvements, net of accumulated depreciation and amortization	22,051	15,702
Office Hardware [Member]
Property, Plant and Equipment [Line Items]
Total capitalized software, furniture, equipment and leasehold improvements, net of accumulated depreciation and amortization	2,380	2,125
Furniture and Fixtures [Member]
Property, Plant and Equipment [Line Items]
Total capitalized software, furniture, equipment and leasehold improvements, net of accumulated depreciation and amortization	1,777	1,479
Leasehold Improvements [Member]
Property, Plant and Equipment [Line Items]
Total capitalized software, furniture, equipment and leasehold improvements, net of accumulated depreciation and amortization	8,129	4,709
Computer Hardware Under Capital Lease [Member]
Property, Plant and Equipment [Line Items]
Total capitalized software, furniture, equipment and leasehold improvements, net of accumulated depreciation and amortization	$ 1,419	$ 1,419