Goodwill - Changes in the Net Carrying Amount of Goodwill (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2017	Jan. 01, 2017	Jan. 03, 2016
Goodwill [Line Items]
Goodwill, Gross		$ 189.3	$ 191.2
Accumulated Impairment Losses		(100.9)	(100.9)
Adjustments to Goodwill		(1.9)
Goodwill, Net	$ 107.1	88.4
Allocation of Goodwill	0.0
Additions to Goodwill	18.7
Americas Commercial
Goodwill [Line Items]
Goodwill, Gross		40.0	40.0
Accumulated Impairment Losses		(16.4)	(16.4)
Adjustments to Goodwill		0.0
Goodwill, Net	0.0	23.6
Allocation of Goodwill	(23.6)
Americas PT
Goodwill [Line Items]
Goodwill, Gross		37.9	37.9
Accumulated Impairment Losses		0.0	0.0
Adjustments to Goodwill		0.0
Goodwill, Net	0.0	37.9
Allocation of Goodwill	(37.9)
Total Americas
Goodwill [Line Items]
Goodwill, Gross		77.9	77.9
Accumulated Impairment Losses		(16.4)	(16.4)
Adjustments to Goodwill		0.0
Goodwill, Net		61.5
EMEA Commercial
Goodwill [Line Items]
Goodwill, Gross		50.4	50.4
Accumulated Impairment Losses		(50.4)	(50.4)
Adjustments to Goodwill		0.0
Goodwill, Net	0.0	0.0
Allocation of Goodwill	0.0
EMEA PT
Goodwill [Line Items]
Goodwill, Gross		22.0	22.0
Accumulated Impairment Losses		(22.0)	(22.0)
Adjustments to Goodwill		0.0
Goodwill, Net	0.0	0.0
Allocation of Goodwill	0.0
Total EMEA
Goodwill [Line Items]
Goodwill, Gross		72.4	72.4
Accumulated Impairment Losses		(72.4)	(72.4)
Adjustments to Goodwill		0.0
Goodwill, Net		0.0
APAC Commercial
Goodwill [Line Items]
Goodwill, Gross		12.1	12.1
Accumulated Impairment Losses		(12.1)	(12.1)
Adjustments to Goodwill		0.0
Goodwill, Net	0.0	0.0
Allocation of Goodwill	0.0
APAC PT
Goodwill [Line Items]
Goodwill, Gross		0.0	1.4
Accumulated Impairment Losses		0.0	0.0
Adjustments to Goodwill		(1.4)
Goodwill, Net	0.0	0.0
Allocation of Goodwill	0.0
Total APAC
Goodwill [Line Items]
Goodwill, Gross		12.1	13.5
Accumulated Impairment Losses		(12.1)	(12.1)
Adjustments to Goodwill		(1.4)
Goodwill, Net		0.0
OCG
Goodwill [Line Items]
Goodwill, Gross		26.9	27.4
Accumulated Impairment Losses		0.0	$ 0.0
Adjustments to Goodwill		(0.5)
Goodwill, Net	0.0	26.9
Allocation of Goodwill	(26.9)
Americas Staffing
Goodwill [Line Items]
Goodwill, Gross		0.0
Accumulated Impairment Losses		0.0
Goodwill, Net	44.6	0.0
Allocation of Goodwill	25.9
Additions to Goodwill	18.7
GTS
Goodwill [Line Items]
Goodwill, Gross		0.0
Accumulated Impairment Losses		0.0
Goodwill, Net	62.5	0.0
Allocation of Goodwill	62.5
International Staffing
Goodwill [Line Items]
Goodwill, Gross		0.0
Accumulated Impairment Losses		0.0
Goodwill, Net	0.0	$ 0.0
Allocation of Goodwill	$ 0.0

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=77989000&loc=SL49117168-202975

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