Pension And Other Postretirement Benefit Programs - Amounts Recognized in AOCI (Details) - USD ($) $ in Millions |
Dec. 31, 2020 |
Dec. 31, 2019 |
|---|---|---|
| Retiree Health and Life Insurance Plans | ||
| Defined Benefit Plan Disclosure [Line Items] | ||
| Net actuarial gain (loss) | $ 25.6 | $ 30.5 |
| United States | Pension Plan | ||
| Defined Benefit Plan Disclosure [Line Items] | ||
| Net actuarial gain (loss) | (106.7) | (123.1) |
| Canadian Pension Plan | Pension Plan | ||
| Defined Benefit Plan Disclosure [Line Items] | ||
| Net actuarial gain (loss) | $ (4.9) | $ (4.8) |
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- Definition 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. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. No definition available.
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