Income Taxes - Components of Deferred Tax Assets (Liabilities) (Details) - USD ($) $ in Millions	Dec. 31, 2022	Dec. 31, 2021
Income Tax Disclosure [Abstract]
Accruals not yet deductible for tax purposes	$ 17.6	$ 17.1
Net operating loss carryforwards	208.4	219.4
Foreign, federal and state credits	9.5	6.4
Employee benefit items	40.3	45.4
Capitalized expenses	36.5	3.9
Intangibles	12.6	15.4
Derivatives and other	44.7	45.4
Sub-total deferred tax assets	369.6	353.0
Valuation allowance	(179.5)	(189.6)
Total deferred tax assets	190.1	163.4
Depreciation and amortization	(89.1)	(78.6)
Other	0.0	(0.2)
Total deferred tax liabilities	(89.1)	(78.8)
Net deferred tax assets	$ 101.0	$ 84.6