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Goodwill and Intangible Assets - Narrative (Details) - USD ($) $ in Millions	3 Months Ended		12 Months Ended
	Jan. 01, 2023	Oct. 02, 2022	Dec. 31, 2023	Jan. 01, 2023	Jan. 02, 2022
Finite-Lived Intangible Assets [Line Items]
Finite-lived intangible assets, amortization expense, next 12 months			$ 20.6
Finite-lived intangible assets, amortization expense, year 2			18.5
Finite-lived intangible assets, amortization expense, year 3			17.9
Finite-lived intangible assets, amortization expense, year 4			17.3
Finite-lived intangible assets, amortization expense, year 5			16.1
Goodwill impairment charge	$ 10.3	$ 30.7	0.0	$ 41.0	$ 0.0
Goodwill, net	151.1		$ 151.1	151.1	114.8
Softworld, Inc.
Finite-Lived Intangible Assets [Line Items]
Reporting unit, percentage of fair value in excess of carrying amount			10.00%
Outsourcing & Consulting
Finite-Lived Intangible Assets [Line Items]
Goodwill impairment charge			$ 0.0	41.0
Goodwill, net	$ 0.0	$ 10.3	0.0	0.0	0.0
Selling, General and Administrative Expenses
Finite-Lived Intangible Assets [Line Items]
Amortization expense			$ 20.9	$ 19.4	$ 13.0