Condensed Consolidated Balance Sheets (Parenthetical) (USD $) In Thousands, except Share data	Sep. 30, 2011	Dec. 31, 2010
Condensed Consolidated Balance Sheets
Trade accounts receivable-billed, allowance	$ 2,472	$ 1,837
Property and equipment, accumulated depreciation	109,879	94,236
Software, accumulated amortization	53,726	45,579
Client contracts, accumulated amortization	152,931	133,218
Current maturities of long-term debt, unamortized original issue discount	0	621
Long-term debt, unamortized original issue discount	$ 31,435	$ 34,841
Preferred stock, par value	$ 0.01	$ 0.01
Preferred stock, shares authorized	10,000,000	10,000,000
Preferred stock, shares issued	0	0
Preferred stock, shares outstanding	0	0
Common stock, par value	$ 0.01	$ 0.01
Common stock, shares authorized	100,000,000	100,000,000
Common stock, shares outstanding	34,079,251	34,120,789
Treasury stock, shares	30,535,019	29,956,808