Consolidated Statements of Operations (Unaudited) - USD ($) shares in Millions, $ in Millions	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022
Income Statement [Abstract]
Revenues from services	$ 4,752.3	$ 5,143.3
Cost of services	3,889.2	4,246.2
Gross profit	863.1	897.1
Selling and administrative expenses	745.2	758.4
Operating profit	117.9	138.7
Interest and other expenses, net	7.5	2.7
Earnings before income taxes	110.4	136.0
Provision for income taxes	32.6	44.4
Net earnings	$ 77.8	$ 91.6
Net earnings (loss) per share - basic	$ 1.53	$ 1.71
Net earnings (loss) per share - diluted	$ 1.51	$ 1.68
Weighted average shares - basic (in shares)	50.9	53.6
Weighted average shares - diluted (in shares)	51.6	54.4