Defined Benefit Plan, Amortization of Actuarial Losses, Amortization Period

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- Definition

Defined Benefit Plan, Recognized Net Gain (Loss) Due to Settlements, Lump-Sum Payout Offer

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- Definition

Multiemployer Plans, Collective-Bargaining Arrangement, Number of Agreements

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Multiemployer Plans, Number of Plans

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- Definition

For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

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- Definition

Amount of actuarial present value of benefits attributed to employee service rendered, excluding assumptions about future compensation level.

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- Definition

Weighted-average interest crediting rate used to determine benefit obligation of defined benefit plan. Plan includes, but is not limited to, cash balance and other defined benefit plans with promised interest crediting rate.

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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.

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No definition available.

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- Definition

Amount of contribution expected to be received by defined benefit plan from employer in next fiscal year following current fiscal year.

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- Definition

Percentage of target investment allocation to total plan assets. Includes, but is not limited to, percentage on weighted-average basis if more than one plan.

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- Definition

Amount of gain (loss) recognized in net periodic benefit (cost) credit from irrevocable action relieving primary responsibility for benefit obligation and eliminating risk related to obligation and assets used to effect settlement.

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- Definition

Amount of cost for defined contribution plan.

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- Definition

Amount, after reclassification adjustment, of tax (expense) benefit for (increase) decrease in accumulated other comprehensive income for defined benefit plan, attributable to parent.

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- Definition

Amount of expenses associated with exit or disposal activities pursuant to an authorized plan. Excludes expenses related to a discontinued operation or an asset retirement obligation.

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Pension and Other Postretirement Benefit Plans - Narrative (Details) $ in Millions	3 Months Ended		12 Months Ended
	Dec. 31, 2020 USD ($) pension_plan agreement	Oct. 03, 2020 USD ($)	Dec. 31, 2020 USD ($) pension_plan agreement	Dec. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)	Dec. 31, 2021 USD ($)
Defined Benefit Plan Disclosure [Line Items]
Accumulated benefit obligation	$ 1,079.6		$ 1,079.6	$ 990.3
Tax (expense) benefit related to defined benefit plans recognized in other comprehensive income (loss)			18.5	13.7	$ (3.0)
Defined benefit plan, loss due to settlement	2.7	$ 10.2	12.9
Charges	$ 8.1		$ 132.0	194.2	88.0
Number of multi-employer pension plans \| pension_plan	2		2
Number of collective bargaining agreements \| agreement	4		4
Defined Contribution Retirement Program
Defined Benefit Plan Disclosure [Line Items]
Defined contribution expense			$ 18.3	$ 17.6	21.5
Unionized Employees \| Multi-employer Plan Total Contributions
Defined Benefit Plan Disclosure [Line Items]
Concentration risk percentage (more than)			5.00%	5.00%
Pension Benefit Plan Curtailment Gain
Defined Benefit Plan Disclosure [Line Items]
Charges				$ 10.6
U.S. \| Minimum
Defined Benefit Plan Disclosure [Line Items]
Debt, weighted average interest rate	4.00%		4.00%	4.00%
Foreign
Defined Benefit Plan Disclosure [Line Items]
Defined contribution expense			$ 17.1	$ 14.0	13.7
Pension \| Minimum
Defined Benefit Plan Disclosure [Line Items]
Period for amortizing actuarial losses			4 years
Pension \| Minimum \| Forecast
Defined Benefit Plan Disclosure [Line Items]
Estimated required contributions to pension plans in next fiscal year						$ 5.0
Pension \| Maximum
Defined Benefit Plan Disclosure [Line Items]
Period for amortizing actuarial losses			34 years
Pension \| Maximum \| Forecast
Defined Benefit Plan Disclosure [Line Items]
Estimated required contributions to pension plans in next fiscal year						$ 10.0
Pension \| U.S.
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, loss due to settlement			$ 0.3	0.1	5.7
Settlement charge					5.4
Pension \| U.S. \| Minimum \| Return Seeking Assets
Defined Benefit Plan Disclosure [Line Items]
Target percentage of asset allocation	45.00%		45.00%
Pension \| U.S. \| Minimum \| Risk Mitigating Assets
Defined Benefit Plan Disclosure [Line Items]
Target percentage of asset allocation	35.00%		35.00%
Pension \| U.S. \| Maximum \| Return Seeking Assets
Defined Benefit Plan Disclosure [Line Items]
Target percentage of asset allocation	65.00%		65.00%
Pension \| U.S. \| Maximum \| Risk Mitigating Assets
Defined Benefit Plan Disclosure [Line Items]
Target percentage of asset allocation	55.00%		55.00%
Pension \| Foreign
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, loss due to settlement			$ 13.0	$ 0.0	$ 0.0
Pension \| Foreign \| Minimum \| Equity Securities
Defined Benefit Plan Disclosure [Line Items]
Target percentage of asset allocation	45.00%		45.00%
Pension \| Foreign \| Minimum \| Fixed Income
Defined Benefit Plan Disclosure [Line Items]
Target percentage of asset allocation	25.00%		25.00%
Pension \| Foreign \| Minimum \| Alternative Investments
Defined Benefit Plan Disclosure [Line Items]
Target percentage of asset allocation	0.00%		0.00%
Pension \| Foreign \| Minimum \| Cash and Other
Defined Benefit Plan Disclosure [Line Items]
Target percentage of asset allocation	0.00%		0.00%
Pension \| Foreign \| Maximum \| Equity Securities
Defined Benefit Plan Disclosure [Line Items]
Target percentage of asset allocation	65.00%		65.00%
Pension \| Foreign \| Maximum \| Fixed Income
Defined Benefit Plan Disclosure [Line Items]
Target percentage of asset allocation	45.00%		45.00%
Pension \| Foreign \| Maximum \| Alternative Investments
Defined Benefit Plan Disclosure [Line Items]
Target percentage of asset allocation	25.00%		25.00%
Pension \| Foreign \| Maximum \| Cash and Other
Defined Benefit Plan Disclosure [Line Items]
Target percentage of asset allocation	15.00%		15.00%
Other Postretirement \| Minimum
Defined Benefit Plan Disclosure [Line Items]
Period for amortizing actuarial losses			1 year
Other Postretirement \| Maximum
Defined Benefit Plan Disclosure [Line Items]
Period for amortizing actuarial losses			17 years