Accounting Policies - Schedule of Undiscounted Amounts and Material Changes in Insurance Claims (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021
Liability For Claims And Claims Adjustment Expense [Line Items]
Undiscounted amount	$ 373.0	$ 345.2
Estimated settlement cost	120.9	130.5
Claim payments, net of recoveries	(163.3)	(135.8)
Change in estimated settlement cost for prior claim years	16.5	33.1
Undiscounted amount	347.1	373.0
Discounted settlement cost estimate	325.2
Workers’ Compensation
Liability For Claims And Claims Adjustment Expense [Line Items]
Undiscounted amount	267.3	275.2
Estimated settlement cost	84.3	92.4
Claim payments, net of recoveries	(86.5)	(94.8)
Change in estimated settlement cost for prior claim years	(20.4)	(5.5)
Undiscounted amount	244.7	267.3
Discounted settlement cost estimate	225.7
Third-Party Liability Claims
Liability For Claims And Claims Adjustment Expense [Line Items]
Undiscounted amount	105.7	70.0
Estimated settlement cost	36.6	38.1
Claim payments, net of recoveries	(76.8)	(41.0)
Change in estimated settlement cost for prior claim years	36.9	38.6
Undiscounted amount	102.4	$ 105.7
Discounted settlement cost estimate	$ 99.5