Income Taxes (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended								12 Months Ended
	Dec. 31, 2011	Sep. 30, 2011	Jun. 30, 2011	Mar. 31, 2011	Dec. 31, 2010	Sep. 30, 2010	Jun. 30, 2010	Mar. 31, 2010	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Current:
Federal									$ (1,160)	$ 18,524	$ 14,946
State									1,282	5,026	3,160
Foreign									5,632	6,118	7,010
Total									5,754	29,668	25,116
Deferred:
Federal									(25,146)	(4,289)	7,224
State									(8,409)	(766)	664
Foreign									962	740	613
Total									(32,593)	(4,315)	8,501
Total, income tax expense	(2,686)	6,713	(38,448)	7,582	1,318	5,166	11,860	7,009	(26,839)	25,353	33,617
Components of income before income taxes
U.S.									(222,337)	45,000	74,102
Foreign									15,709	4,333	2,349
(Loss) income before income tax expense	(6,358)	17,190	(234,591)	17,131	3,148	11,376	19,368	15,441	(206,628)	49,333	76,451
Deferred tax assets:
Compensation and benefits	9,565				13,999				9,565	13,999
Net operating loss and capital loss carry forward	15,810				14,804				15,810	14,804
Share-based compensation	12,430				12,455				12,430	12,455
Allowance for doubtful accounts	663				569				663	569
Tax benefits on uncertain tax positions	2,846				2,459				2,846	2,459
Goodwill and other intangibles	2,370								2,370
Depreciation					1,868					1,868
Other	8,914				4,373				8,914	4,373
Total deferred tax assets	52,598				50,527				52,598	50,527
Less: valuation allowance	16,279				12,674				16,279	12,674
Total deferred tax assets, net of valuation allowance	36,319				37,853				36,319	37,853
Deferred tax liabilities:
Goodwill and other intangibles					(29,615)					(29,615)
Depreciation	(2,038)								(2,038)
Capitalized software	(17,769)				(20,122)				(17,769)	(20,122)
Other	(738)				(1,328)				(738)	(1,328)
Total deferred tax liabilities	(20,545)				(51,065)				(20,545)	(51,065)
Net deferred tax assets (liabilities)	$ 15,774				$ (13,212)				$ 15,774	$ (13,212)