Goodwill and Intangible Assets - Schedule of Goodwill by Reportable Segment (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2017	Dec. 31, 2016
Goodwill
Beginning balance	$ 13,823	$ 11,810
Goodwill recorded in connection with business combinations	3,694	2,146
Foreign currency translation	131	(133)
Ending balance	17,648	13,823
Recovery Audit Services – Americas
Goodwill
Beginning balance	10,755	10,755
Goodwill recorded in connection with business combinations	2,685	0
Foreign currency translation	0	0
Ending balance	13,440	10,755
Recovery Audit Services – Europe/Asia- Pacific
Goodwill
Beginning balance	680	813
Goodwill recorded in connection with business combinations	869	0
Foreign currency translation	131	(133)
Ending balance	1,680	680
Adjacent Services
Goodwill
Beginning balance	2,388	242
Goodwill recorded in connection with business combinations	140	2,146
Foreign currency translation	0	0
Ending balance	$ 2,528	$ 2,388

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13816-109267

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6388280&loc=d3e13770-109266

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=64834752&loc=SL49117168-202975

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Amount of increase in asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized resulting from a business combination.

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Amount of foreign currency translation gain (loss) which increases (decreases) an asset representing future economic benefits from other assets acquired in a business combination that are not individually identified and separately recognized.

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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