Capitalized Software, Furniture, Equipment and Leasehold Improvements (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2012	Dec. 31, 2011
Capitalized software development costs, furniture, equipment and leasehold improvements, net of accumulated depreciation and amortization
Accumulated depreciation and amortization	$ (37,087)	$ (30,470)
Total capitalized software, furniture, equipment and leasehold improvements, net of accumulated depreciation and amortization	18,009	14,460
Software development costs [Member]
Capitalized software development costs, furniture, equipment and leasehold improvements, net of accumulated depreciation and amortization
Total capitalized software, furniture, equipment and leasehold improvements, net of accumulated depreciation and amortization	29,662	24,440
Computer hardware and related software [Member]
Capitalized software development costs, furniture, equipment and leasehold improvements, net of accumulated depreciation and amortization
Total capitalized software, furniture, equipment and leasehold improvements, net of accumulated depreciation and amortization	15,702	11,126
Office hardware [Member]
Capitalized software development costs, furniture, equipment and leasehold improvements, net of accumulated depreciation and amortization
Total capitalized software, furniture, equipment and leasehold improvements, net of accumulated depreciation and amortization	2,125	1,832
Furniture and fixtures [Member]
Capitalized software development costs, furniture, equipment and leasehold improvements, net of accumulated depreciation and amortization
Total capitalized software, furniture, equipment and leasehold improvements, net of accumulated depreciation and amortization	1,479	1,446
Leasehold improvements [Member]
Capitalized software development costs, furniture, equipment and leasehold improvements, net of accumulated depreciation and amortization
Total capitalized software, furniture, equipment and leasehold improvements, net of accumulated depreciation and amortization	4,709	4,667
Computer hardware under capital lease [Member]
Capitalized software development costs, furniture, equipment and leasehold improvements, net of accumulated depreciation and amortization
Total capitalized software, furniture, equipment and leasehold improvements, net of accumulated depreciation and amortization	$ 1,419	$ 1,419