Segment Disclosures - Segment Earnings (loss) From Operations (Details) - USD ($) $ in Millions	3 Months Ended
Apr. 03, 2022	Apr. 04, 2021
Earnings (loss) from Operations
Gross profit	$ 258.6	$ 213.3
SG&A expenses	(235.2)	(202.7)
Earnings (loss) from operations	23.4	10.6
Gain (loss) on investment in Persol Holdings	(67.2)	30.0
Loss on currency translation from liquidation of subsidiary	(20.4)	0.0
Other income (expense), net	2.8	(3.4)
Earnings (loss) before taxes and equity in net earnings (loss) of affiliate	(61.4)	37.2
Corporate
Earnings (loss) from Operations
Earnings (loss) from operations	(24.5)	(21.9)
Professional & Industrial \| Reporting Segments
Earnings (loss) from Operations
Gross profit	83.1	75.9
SG&A expenses	(71.4)	(69.4)
Earnings (loss) from operations	11.7	6.5
Science, Engineering & Technology \| Reporting Segments
Earnings (loss) from Operations
Gross profit	73.8	53.2
SG&A expenses	(53.2)	(35.7)
Earnings (loss) from operations	20.6	17.5
Education \| Reporting Segments
Earnings (loss) from Operations
Gross profit	26.6	17.2
SG&A expenses	(18.6)	(14.2)
Earnings (loss) from operations	8.0	3.0
Outsourcing & Consulting \| Reporting Segments
Earnings (loss) from Operations
Gross profit	37.3	31.3
SG&A expenses	(34.3)	(28.4)
Earnings (loss) from operations	3.0	2.9
International \| Reporting Segments
Earnings (loss) from Operations
Gross profit	37.8	35.7
SG&A expenses	(33.2)	(33.1)
Earnings (loss) from operations	$ 4.6	$ 2.6

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