Income Taxes - Net Deferred Income Tax Asset (Liability) (Details) - USD ($) $ in Millions		Dec. 31, 2019	Dec. 31, 2018
Deferred income tax asset (liability):
Depreciation and amortization		$ (366.7)	$ (371.2)
Investment in partnership		(38.1)	0.0
Right of use assets		(30.5)	0.0
Unremitted earnings		(29.0)	(8.3)
Inventory basis differences		32.7	27.8
Accrued liabilities		91.3	87.1
Lease obligations		30.5	0.0
Share-based compensation		23.2	19.6
Federal benefit of unrecognized tax positions		20.7	18.2
Loss and credit carryforwards		373.3	359.2
R&D credit carryforwards		54.1	58.8
Interest carryforwards		60.5	76.1
Other, net		4.1	9.5
Subtotal		226.1	276.8
Valuation allowance	[1]	(501.3)	(557.9)
Net deferred income tax liability:		(275.2)	(281.1)
Deferred income tax assets		5.4	1.2
Deferred income tax liabilities		$ (280.6)	$ (282.3)

[1] The movement in the valuation allowance balance differs from the amount in the effective tax rate reconciliation due to adjustments affecting balance sheet only items and foreign currency.