Employee Retirement Plans and Postretirement Benefits - Projected Benefit Obligation (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Change in benefit obligation
Prior year benefit obligation	$ 5,744.5	$ 6,276.2
Service cost, net of expected employee contributions	6.5	8.3
Interest cost	120.0	108.5
Actual employee contributions	0.3	0.4
Actuarial (gain) loss	(1,325.6)	(264.7)
Plan amendments	(0.1)	0.0
Benefits paid	(302.5)	(333.4)
Curtailment, settlement and special termination	(460.4)	(35.4)
Foreign currency exchange rate change	(326.4)	(15.4)
Benefit obligation at end of year	3,456.3	5,744.5	$ 6,276.2
Change in plan assets
Prior year fair value of assets	5,667.5	5,958.4
Actual return on plan assets	(1,272.9)	55.5
Employer contributions	38.2	42.5
Curtailment, settlement and special termination	(460.6)	(35.4)
Benefits and plan expenses paid	(302.5)	(333.4)
Foreign currency exchange rate change	(333.2)	(20.5)
Fair value of plan assets at end of year	3,336.8	5,667.5	5,958.4
Funded (underfunded) status	(119.5)	(77.0)
Amounts recognized in the Consolidated Balance Sheets
Other non-current assets	397.2	622.9
Accounts payable and other current liabilities	(43.4)	(45.5)
Pension and postretirement benefits	(473.3)	(654.4)
Net amounts recognized	(119.5)	(77.0)
Amounts in Accumulated Other Comprehensive Loss (Income) not yet recognized as components of net periodic pension cost or (benefit), pre-tax:
Net actuarial (gain) loss	488.2	411.1
Net prior service (benefit) cost	8.9	6.9
Total not yet recognized	497.1	418.0
Pension
Change in benefit obligation
Prior year benefit obligation	5,095.8	5,571.5
Service cost, net of expected employee contributions	1.0	2.3
Interest cost	103.9	93.9	120.5
Actual employee contributions	0.3	0.4
Actuarial (gain) loss	(1,181.0)	(227.4)
Plan amendments	0.0	0.0
Benefits paid	(263.8)	(293.1)
Curtailment, settlement and special termination	(460.6)	(35.4)
Foreign currency exchange rate change	(317.6)	(16.4)
Benefit obligation at end of year	2,978.0	5,095.8	5,571.5
Change in plan assets
Prior year fair value of assets	5,667.5	5,958.4
Actual return on plan assets	(1,272.9)	55.5
Employer contributions	(0.5)	2.2
Curtailment, settlement and special termination	(460.6)	(35.4)
Benefits and plan expenses paid	(263.8)	(293.1)
Foreign currency exchange rate change	(333.2)	(20.5)
Fair value of plan assets at end of year	3,336.8	5,667.5	5,958.4
Funded (underfunded) status	358.8	571.7
Amounts recognized in the Consolidated Balance Sheets
Other non-current assets	397.2	622.9
Accounts payable and other current liabilities	(3.9)	(4.1)
Pension and postretirement benefits	(34.5)	(47.1)
Net amounts recognized	358.8	571.7
Funded status:
Accumulated benefit obligation	38.4	51.2
Projected benefit obligation	38.4	51.2
Fair value of plan assets	0.0	0.0
Amounts in Accumulated Other Comprehensive Loss (Income) not yet recognized as components of net periodic pension cost or (benefit), pre-tax:
Net actuarial (gain) loss	766.4	553.4
Net prior service (benefit) cost	9.7	10.1
Total not yet recognized	776.1	563.5
OPEB
Change in benefit obligation
Prior year benefit obligation	648.7	704.7
Service cost, net of expected employee contributions	5.5	6.0
Interest cost	16.1	14.6	18.8
Actual employee contributions	0.0	0.0
Actuarial (gain) loss	(144.6)	(37.3)
Plan amendments	(0.1)	0.0
Benefits paid	(38.7)	(40.3)
Curtailment, settlement and special termination	0.2	0.0
Foreign currency exchange rate change	(8.8)	1.0
Benefit obligation at end of year	478.3	648.7	704.7
Change in plan assets
Prior year fair value of assets	0.0	0.0
Actual return on plan assets	0.0	0.0
Employer contributions	38.7	40.3
Curtailment, settlement and special termination	0.0	0.0
Benefits and plan expenses paid	(38.7)	(40.3)
Foreign currency exchange rate change	0.0	0.0
Fair value of plan assets at end of year	0.0	0.0	$ 0.0
Funded (underfunded) status	(478.3)	(648.7)
Amounts recognized in the Consolidated Balance Sheets
Other non-current assets	0.0	0.0
Accounts payable and other current liabilities	(39.5)	(41.4)
Pension and postretirement benefits	(438.8)	(607.3)
Net amounts recognized	(478.3)	(648.7)
Amounts in Accumulated Other Comprehensive Loss (Income) not yet recognized as components of net periodic pension cost or (benefit), pre-tax:
Net actuarial (gain) loss	(278.2)	(142.3)
Net prior service (benefit) cost	(0.8)	(3.2)
Total not yet recognized	$ (279.0)	$ (145.5)