Goodwill - Changes in the Net Carrying Amount of Goodwill (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 29, 2020	Mar. 31, 2019
Goodwill [Roll Forward]
Goodwill, beginning balance	$ 127.8
Additions to Goodwill	19.9
Goodwill, Impairment Loss	(147.7)	$ 0.0
Goodwill, ending balance	0.0
Americas Staffing
Goodwill [Roll Forward]
Goodwill, beginning balance	58.5
Additions to Goodwill	19.9
Goodwill, Impairment Loss	(78.4)
Goodwill, ending balance	0.0
Global Talent Solutions
Goodwill [Roll Forward]
Goodwill, beginning balance	69.3
Additions to Goodwill	0.0
Goodwill, Impairment Loss	(69.3)
Goodwill, ending balance	$ 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://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
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-Section 45
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- Definition

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.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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- Definition

Amount of loss from the write-down of an asset representing the future economic benefits arising 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
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- Definition

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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