Accumulated Other Comprehensive Income (Loss) - Reclassifications (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Reclassifications out of AOCI [Line Items]
Other income (expense)- net	$ (5.3)	$ 13.9	$ 14.9
Interest expense	221.9	193.2	206.4
Tax benefit (expense)	34.2	28.8	(23.4)
Net income (loss)	(43.7)	4.1	(65.9)
Reclassification out of Accumulated Other Comprehensive Income
Reclassifications out of AOCI [Line Items]
Interest expense	(75.4)	(13.2)	3.9
Total before tax	(78.2)	(13.0)	5.8
Tax benefit (expense)	20.7	3.4	(1.5)
Net income (loss)	(57.5)	(9.6)	4.3
Amortization of prior service costs | Reclassification out of Accumulated Other Comprehensive Income
Reclassifications out of AOCI [Line Items]
Other income (expense)- net	(0.4)	0.1	(0.4)
Amortization of actuarial gain/loss | Reclassification out of Accumulated Other Comprehensive Income
Reclassifications out of AOCI [Line Items]
Other income (expense)- net	$ (2.4)	$ 0.1	$ 2.3