Operating Segments and Related Information - Schedule of Segment Information (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Segment information
Revenue, net of refund liabilities	$ 49,633	$ 43,320	$ 42,102	$ 36,721	$ 47,074	$ 42,467	$ 38,510	$ 33,569	$ 171,776	$ 161,620	$ 140,844
Net income from continuing operations									3,351	4,556	2,229
Income tax expense	(252)	597	189	787	526	930	879	627	1,321	2,962	1,242
Interest expense, net	363	416	486	398	1,312	142	48	37	1,663	1,539	(153)
EBIT									6,335	9,057	3,318
Depreciation of property, equipment and software assets	2,074	1,713	2,360	1,223	1,107	1,133	1,109	1,220	7,370	4,569	5,033
Amortization of intangible assets	871	872	864	788	1,468	722	722	722	3,395	3,634	1,832
EBITDA									17,100	17,260	10,183
Foreign currency transaction losses (gains) on short-term intercompany balances	272	70	880	(220)	(263)	(418)	(957)	(552)	1,002	(2,190)	84
Acquisition-related charges									(1,628)	(2,283)
Transformation and severance expenses									3,122	1,666	(1,329)
Other (income) loss	5	$ (1)	$ 5	$ 12	17	$ 17	$ 5	$ (199)	21	(160)	(121)
Stock-based compensation									5,056	7,052	5,123
Adjusted EBITDA									24,673	21,345	16,598
Capital expenditures									10,398	9,355	5,887
Allocated assets	97,357				73,035				104,652	97,357	73,035
Cash and cash equivalents	18,823				15,723				13,973	18,823	15,723	$ 15,122
Restricted cash	51								46	51
Deferred loan costs	131								65	131
Deferred income taxes	1,538								2,895	1,538
Total assets	120,218				93,474				124,829	120,218	93,474
Long-lived assets	54,006								37,540	54,006
Continuing operations
Segment information
Cash and cash equivalents	18,823				15,723				13,973	18,823	15,723
Restricted cash	51				47				46	51	47
Deferred loan costs	0									0
Deferred income taxes	1,538				2,269				3,561	1,538	2,269
Prepaid expenses and other assets	910				800				910	910	800
Discontinued Operations
Segment information
Discontinued operations	1,539				1,600				1,687	1,539	1,600
United States
Segment information
Revenue, net of refund liabilities									100,458	93,447	80,857
Cash and cash equivalents									5,700
Long-lived assets	47,371								34,236	47,371
United Kingdom
Segment information
Revenue, net of refund liabilities									27,774	23,408	17,501
Long-lived assets	5,510								2,909	5,510
Canada
Segment information
Revenue, net of refund liabilities									14,700	14,375	14,531
Cash and cash equivalents									1,200
Australia
Segment information
Revenue, net of refund liabilities									8,397	8,732	7,354
France
Segment information
Revenue, net of refund liabilities									6,721	5,987	6,934
Mexico
Segment information
Revenue, net of refund liabilities									3,793	5,385	4,900
Brazil
Segment information
Revenue, net of refund liabilities									1,799	2,053	1,169
Spain
Segment information
Revenue, net of refund liabilities									1,443	1,127	964
Hong Kong
Segment information
Revenue, net of refund liabilities									1,219	889	824
Thailand
Segment information
Revenue, net of refund liabilities									1,094	699	654
Ireland
Segment information
Revenue, net of refund liabilities									741	929	337
Colombia
Segment information
Revenue, net of refund liabilities									465	709	583
New Zealand
Segment information
Revenue, net of refund liabilities									338	899	979
Other
Segment information
Revenue, net of refund liabilities									2,834	2,981	3,257
Cash and cash equivalents									7,100
Long-lived assets	1,125								395	1,125
Recovery Audit Services – Americas
Segment information
Revenue, net of refund liabilities									115,920	113,122	99,861
EBIT									26,602	29,163	25,476
Depreciation of property, equipment and software assets									5,545	3,165	3,750
Amortization of intangible assets									1,664	1,919	1,477
EBITDA									33,811	34,247	30,703
Foreign currency transaction losses (gains) on short-term intercompany balances									367	(249)	31
Acquisition-related charges									0	0
Transformation and severance expenses									944	313	(517)
Other (income) loss									(4)	751	0
Stock-based compensation									0	0	0
Adjusted EBITDA									35,118	35,062	31,251
Capital expenditures									2,050	2,389	4,393
Allocated assets	65,397				47,690				71,211	65,397	47,690
Total assets	65,397				47,690				71,211	65,397	47,690
Recovery Audit Services – Europe/Asia- Pacific
Segment information
Revenue, net of refund liabilities									49,526	44,372	37,335
EBIT									12,413	11,700	6,455
Depreciation of property, equipment and software assets									683	599	529
Amortization of intangible assets									172	142	0
EBITDA									13,268	12,441	6,984
Foreign currency transaction losses (gains) on short-term intercompany balances									1,044	(1,769)	107
Acquisition-related charges									0	0
Transformation and severance expenses									1,194	655	(312)
Other (income) loss									8	184	0
Stock-based compensation									0	0	0
Adjusted EBITDA									15,514	11,511	7,403
Capital expenditures									1,200	2,383	600
Allocated assets	22,474				14,813				26,147	22,474	14,813
Total assets	22,474				14,813				26,147	22,474	14,813
Adjacent Services
Segment information
Revenue, net of refund liabilities									6,330	4,126	3,648
EBIT									(5,231)	(7,942)	(4,617)
Depreciation of property, equipment and software assets									1,142	805	754
Amortization of intangible assets									1,559	1,573	355
EBITDA									(2,530)	(5,564)	(3,508)
Foreign currency transaction losses (gains) on short-term intercompany balances									14	(9)	17
Acquisition-related charges									0	0
Transformation and severance expenses									66	320	(258)
Other (income) loss									0	(195)	(121)
Stock-based compensation									0	0	0
Adjusted EBITDA									(2,450)	(5,448)	(3,354)
Capital expenditures									257	1,335	894
Allocated assets	9,486				10,532				7,294	9,486	10,532
Total assets	9,486				10,532				7,294	9,486	10,532
Corporate Support
Segment information
Revenue, net of refund liabilities									0	0	0
EBIT									(27,449)	(23,864)	(23,996)
Depreciation of property, equipment and software assets									0	0	0
Amortization of intangible assets									0	0	0
EBITDA									(27,449)	(23,864)	(23,996)
Foreign currency transaction losses (gains) on short-term intercompany balances									(423)	(163)	(71)
Acquisition-related charges									(1,628)	(2,283)
Transformation and severance expenses									918	378	(242)
Other (income) loss									17	(900)	0
Stock-based compensation									5,056	7,052	5,123
Adjusted EBITDA									(23,509)	(19,780)	(18,702)
Capital expenditures									6,891	3,248	0
Allocated assets	0				0				0	0	0
Total assets	22,861				20,439				20,177	22,861	20,439
Corporate Support | Continuing operations
Segment information
Cash and cash equivalents	18,823				15,723				13,973	18,823	15,723
Restricted cash	51				47				46	51	47
Deferred loan costs	0									0
Deferred income taxes	1,538				2,269				3,561	1,538	2,269
Prepaid expenses and other assets	910				800				910	910	800
Corporate Support | Discontinued Operations
Segment information
Discontinued operations	$ 1,539				$ 1,600				$ 1,687	$ 1,539	$ 1,600