Goodwill (Details) $ in Thousands	9 Months Ended
Sep. 30, 2019 USD ($)
Goodwill [Roll Forward]
Balance as of December 31, 2018	$ 209,958
Foreign currency translation adjustments	27
Balance as of September 30, 2019	209,985
Temporary and consulting staffing
Goodwill [Roll Forward]
Balance as of December 31, 2018	134,067
Foreign currency translation adjustments	(87)
Balance as of September 30, 2019	133,980
Permanent placement staffing
Goodwill [Roll Forward]
Balance as of December 31, 2018	26,058
Foreign currency translation adjustments	(24)
Balance as of September 30, 2019	26,034
Risk consulting and internal audit services
Goodwill [Roll Forward]
Balance as of December 31, 2018	49,833
Foreign currency translation adjustments	138
Balance as of September 30, 2019	$ 49,971

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://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=77989000&loc=SL49117168-202975

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=99380562&loc=d3e13770-109266

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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.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (f)
-URI http://asc.fasb.org/extlink&oid=108376223&loc=d3e13816-109267

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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.

+ References

No definition available.

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