Income Taxes Reconciliation of income tax expense and rate based on the U.S. statutory rate to the Companys income tax expense (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2012		Dec. 31, 2011		Dec. 31, 2010
Income Tax Expense (Benefit), Continuing Operations, Income Tax Reconciliation [Abstract]
Income tax expense based on the U.S. statutory rate	$ 11,205		$ 7,046		$ (1,101)
Effect of impairment charge related to a goodwill write-down	0.00%		0.00%		(92.50%)
Effect of impairment charge related to a goodwill write-down	0		0		2,909
Effect of settlement with the DOJ	0	[1]	0	[1]	(863)	[1]
Effect of charge related to the UK OFT matter	0		(3,381)		0
State income taxes, net of federal tax benefit	1,013		684		563
Permanent items	148		164		283
Effect of foreign operations	2		289		1,373
Net change in uncertain tax positions	(274)		(139)		119
Adjustment to deferred taxes, pertaining to prior years	0		0		558
Change in valuation allowance - foreign loss carryforwards	477		634		3,293
HIRE Act income tax credit	0		(947)		0
Effective Income Tax Rate Reconciliation, Tax Credits, Other	0.00%		(4.70%)		0.00%
Stock-based compensation	382		689		408
Other	(371)		91		126
Income tax expense	$ 12,582		$ 5,130		$ 7,668
Effective Income Tax Rate, Continuing Operations, Tax Rate Reconciliation [Abstract]
Income tax expense based on the U.S. statutory rate (as a percentage)	35.00%		35.00%		35.00%
Effect of charge related to DOJ matter, as a percentage	0.00%	[1]	0.00%	[1]	27.40%	[1]
State income taxes, net of federal tax benefit, as a percentage	3.20%		3.40%		(17.90%)
Permanent items, as a percentage	0.50%		0.80%		(9.00%)
Effect of foreign operations, as a percenage	0.00%		1.40%		(43.60%)
Net change in uncertain tax positions, as a percentage	(0.90%)		(0.70%)		(3.80%)
Adjustment to deferred taxes, pertaining to prior years, as a percentage	0.00%		0.00%		(17.70%)
Change in valuation allowance - federal foreign tax credits, as a percentage	0.00%		(16.80%)		0.00%
Change in valuation allowance - foreign loss carryforwards, as a percentage	1.50%		3.20%		(104.70%)
Stock-based compensation, as a percentage	1.20%		3.40%		(13.00%)
Other, as a perentage	(1.20%)		0.50%		(4.00%)
Income tax expense, as a percentage	39.30%		25.50%		(243.70%)

[1] The Company paid $2.4 million in 2010 to settle a claim brought by the U.S. Department of Justice ("DOJ") and an individual relator. The Company originally reserved $4.3 million in 2009 and reversed $1.8 million concurrent with the settlement through "Operating and administrative expenses" in the consolidated statements of operations.