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.

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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.

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Amount of increase (decrease) from adjustments after acquisition date under purchase accounting 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.

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Goodwill and Intangible Assets - Rollforward (Details) - USD ($) $ in Millions	3 Months Ended	12 Months Ended
	Mar. 29, 2020	Jan. 02, 2022	Jan. 03, 2021	Dec. 29, 2019
Goodwill [Roll Forward]
Goodwill, beginning balance	$ 127.8	$ 3.5	$ 127.8
Additions to Goodwill		111.3	23.4
Goodwill impairment charge	(147.7)	0.0	(147.7)	$ 0.0
Goodwill, ending balance		114.8	3.5	127.8
Science, Engineering & Technology
Goodwill [Roll Forward]
Goodwill, beginning balance		0.0
Additions to Goodwill		111.3
Goodwill impairment charge		0.0
Goodwill, ending balance		111.3	0.0
Americas Staffing
Goodwill [Roll Forward]
Goodwill, beginning balance	58.5	0.0	58.5
Additions to Goodwill			19.9
Goodwill impairment charge			(78.4)
Goodwill, ending balance			0.0	58.5
Global Talent Solutions
Goodwill [Roll Forward]
Goodwill, beginning balance	69.3	0.0	69.3
Additions to Goodwill			0.0
Goodwill impairment charge			(69.3)
Goodwill, ending balance			0.0	69.3
Education
Goodwill [Roll Forward]
Goodwill, beginning balance	$ 0.0	3.5	0.0
Additions to Goodwill		0.0	3.5
Goodwill impairment charge		0.0	0.0
Goodwill, ending balance		$ 3.5	$ 3.5	$ 0.0