Revenue - Disaggregation of Revenues by Geographic Region (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Oct. 02, 2022	Oct. 03, 2021	Oct. 02, 2022	Oct. 03, 2021
Disaggregation of Revenue [Line Items]
Revenue	$ 1,167.9	$ 1,195.4	$ 3,731.6	$ 3,659.4
Americas
Disaggregation of Revenue [Line Items]
Revenue	943.5	934.9	2,986.4	2,880.4
Asia-Pacific
Disaggregation of Revenue [Line Items]
Revenue	10.3	10.7	32.6	28.3
Science, Engineering & Technology
Disaggregation of Revenue [Line Items]
Revenue	321.3	306.2	962.7	859.1
Science, Engineering & Technology | Americas
Disaggregation of Revenue [Line Items]
Revenue	317.2	304.3	951.4	854.1
Science, Engineering & Technology | Europe
Disaggregation of Revenue [Line Items]
Revenue	4.1	1.9	11.3	5.0
Outsourcing & Consulting
Disaggregation of Revenue [Line Items]
Revenue	118.5	113.4	352.0	320.0
Outsourcing & Consulting | Americas
Disaggregation of Revenue [Line Items]
Revenue	103.1	97.5	302.5	274.9
Outsourcing & Consulting | Europe
Disaggregation of Revenue [Line Items]
Revenue	5.1	5.2	16.9	16.8
Outsourcing & Consulting | Asia-Pacific
Disaggregation of Revenue [Line Items]
Revenue	10.3	10.7	32.6	28.3
International
Disaggregation of Revenue [Line Items]
Revenue	215.5	256.8	715.9	810.1
International | Americas
Disaggregation of Revenue [Line Items]
Revenue	10.6	14.1	31.5	81.2
International | Europe
Disaggregation of Revenue [Line Items]
Revenue	$ 204.9	$ 242.7	$ 684.4	$ 728.9