Pension and Other Benefit Programs (Schedule of Amounts in Accumulated Other Comprehensive) (Details) - USD ($) $ in Millions	Dec. 31, 2020	Dec. 31, 2019
U.S. Pension Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Net actuarial (loss) gain	$ (142.6)	$ (540.7)
Accumulated other comprehensive (loss) income	(142.6)	(540.7)
U.S. Defined-Benefit Retiree Health And Life Insurance Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Net actuarial (loss) gain	17.9	32.8
Prior service credit	1.7	2.0
Accumulated other comprehensive (loss) income	$ 19.6	$ 34.8

Amount, before tax, of accumulated other comprehensive (income) loss for defined benefit plan, that has not been recognized in net periodic benefit cost (credit).

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Amount, before tax, of accumulated other comprehensive income (loss) for gain (loss) of defined benefit plan, that has not been recognized in net periodic benefit (cost) credit.

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Amount, before tax, of accumulated other comprehensive (income) loss for cost (credit) of benefit change attributable to participants' prior service from plan amendment or plan initiation of defined benefit plan, that has not been recognized in net periodic benefit cost (credit).

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