Goodwill (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020
Goodwill [Roll Forward]
Beginning balance	$ 223,055	$ 210,364
Acquisitions		12,199
Foreign currency translation adjustments	(200)	492
Ending balance	222,855	223,055
Temporary and consultant staffing
Goodwill [Roll Forward]
Beginning balance	134,511	134,210
Acquisitions		0
Foreign currency translation adjustments	73	301
Ending balance	134,584	134,511
Permanent placement staffing
Goodwill [Roll Forward]
Beginning balance	26,180	26,097
Acquisitions		0
Foreign currency translation adjustments	9	83
Ending balance	26,189	26,180
Risk consulting and internal audit services
Goodwill [Roll Forward]
Beginning balance	62,364	50,057
Acquisitions		12,199
Foreign currency translation adjustments	(282)	108
Ending balance	$ 62,082	$ 62,364

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/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
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-URI http://asc.fasb.org/extlink&oid=120398452&loc=d3e534808-122878

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
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Reference 3: http://www.xbrl.org/2003/role/exampleRef
-Publisher FASB
-Name Accounting Standards Codification
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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.

+ References

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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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