- Changes in Carrying Amount of Goodwill (Details) - USD ($) $ in Thousands	3 Months Ended
Apr. 01, 2018	Dec. 31, 2017
Goodwill [Line Items]
Goodwill before impairment	$ 319,178	$ 338,773
Accumulated impairment loss	(95,079)	(112,079)
Goodwill, net	224,099	226,694
Divested goodwill before impairment	(19,054)
Divested accumulated impairment loss	17,000
Foreign currency translation	(541)
PeopleReady
Goodwill [Line Items]
Goodwill before impairment	106,304	106,304
Accumulated impairment loss	(46,210)	(46,210)
Goodwill, net	60,094	60,094
PeopleManagement
Goodwill [Line Items]
Goodwill before impairment	81,092	100,146
Accumulated impairment loss	(33,700)	(50,700)
Goodwill, net	47,392	49,446
Divested goodwill before impairment	(19,054)
Divested accumulated impairment loss	17,000
PeopleScout
Goodwill [Line Items]
Goodwill before impairment	131,782	132,323
Accumulated impairment loss	(15,169)	(15,169)
Goodwill, net	116,613	$ 117,154
Foreign currency translation	$ (541)

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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