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Commitments and Contingencies - Narrative (Details) - USD ($) shares in Millions, $ in Millions		3 Months Ended	12 Months Ended
	Feb. 03, 2014	Jun. 30, 2019	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Loss Contingencies [Line Items]
Settlement agreement (as defined therein) and tax deduction			$ 1,490.0
U.S federal tax liability, decrease			525.0
Principal contractual obligations including agreements to purchase an estimated amount of goods, including raw materials, or services			128.2
Asset retirement obligation liabilities			10.6	$ 10.7
Assets held for sale			1,189.7	1,141.9
Accumulated depreciation			2,474.7	2,378.2
Accretion expense			0.3	0.3	$ 0.3
Buildings
Loss Contingencies [Line Items]
Assets held for sale			3.8	3.6
Accumulated depreciation, Depletion and Amortization, Property, Plant and Equipment, Period Increase (Decrease)				4.2
Accumulated depreciation			1.3	1.0
Leasehold Improvements
Loss Contingencies [Line Items]
Assets held for sale			5.9	$ 6.4
Accumulated depreciation			$ 4.4
WRG Asbestos PI Trust and WRG Asbestos PD Trust
Loss Contingencies [Line Items]
Original number of shares expected to be issued under settlement agreement, adjusted	18
North American Foam Trays And Absorbent Pads
Loss Contingencies [Line Items]
Proceeds from sale of businesses	$ 929.7	$ 59.0