Segment Information (Details) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2015 USD ($)	Jun. 30, 2014 USD ($)	Jun. 30, 2015 USD ($) segment	Jun. 30, 2014 USD ($)
Segment Reporting, Reconciling Item for Operating Profit from Segment to Consolidated
Revenues	$ 304,398	$ 288,216	$ 592,175	$ 563,565
Reimbursements	20,018	18,837	38,857	32,846
Total revenues	324,416	307,053	631,032	596,411
Segment operating earnings	20,729	20,867	35,721	36,671
Net corporate interest expense	(2,042)	(1,551)	(3,906)	(2,852)
Special charges	(4,242)	0	(5,305)	0
Income before income taxes	8,887	17,556	$ 14,409	28,430
Number of operating segments (segments) \| segment			4
Americas
Segment Reporting, Reconciling Item for Operating Profit from Segment to Consolidated
Revenues	99,190	93,601	$ 188,657	181,492
Segment operating earnings	9,896	8,142	14,872	15,076
Europe, Middle East, Africa and Asia-Pacific (EMEA/AP)
Segment Reporting, Reconciling Item for Operating Profit from Segment to Consolidated
Revenues	97,191	87,246	188,454	167,582
Segment operating earnings	1,106	4,310	2,634	6,210
Broadspire
Segment Reporting, Reconciling Item for Operating Profit from Segment to Consolidated
Revenues	73,693	66,706	143,365	131,464
Segment operating earnings	6,006	2,715	9,543	4,718
Legal Settlement Administration
Segment Reporting, Reconciling Item for Operating Profit from Segment to Consolidated
Revenues	34,324	40,663	71,699	83,027
Segment operating earnings	3,721	5,700	8,672	10,667
Corporate Segment
Segment Reporting, Reconciling Item for Operating Profit from Segment to Consolidated
Unallocated corporate and shared (costs) and credits, net	(3,046)	53	(7,342)	(1,690)
Net corporate interest expense	(2,042)	(1,551)	(3,906)	(2,852)
Stock option expense	(178)	(202)	(327)	(496)
Amortization of customer-relationship intangible assets	(2,334)	(1,611)	(4,432)	(3,203)
Special charges	$ (4,242)	$ 0	$ (5,305)	$ 0

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Segment Reporting, Unallocated corporate and shared costs, net

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Amount of the cost of borrowed funds accounted for as interest expense.

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Number of operating segments. An operating segment is a component of an enterprise: (a) that engages in business activities from which it may earn revenues and incur expenses (including revenues and expenses relating to transactions with other components of the same enterprise), (b) whose operating results are regularly reviewed by the enterprise's chief operating decision maker to make decisions about resources to be allocated to the segment and assess its performance, and (c) for which discrete financial information is available. An operating segment may engage in business activities for which it has yet to earn revenues, for example, start-up operations may be operating segments before earning revenues.

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