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Employee Benefit Plans and Other Postretirement Benefits - Additional Information (Details) - USD ($) shares in Millions, $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2023 | Dec. 31, 2022 | Dec. 31, 2021
Amounts Recognized in Accumulated Other Comprehensive Loss (Income) (Pre-Tax): |  |  |
Accumulated benefit obligation for plans with obligations in excess of plan assets | $ 42.9 | $ 1,100.0 |
Defined Benefit Plan, Pension Plan Benefit Obligation in Excess of Plan Assets, Plan Assets | $ 334.3 | 1,200.0 |
Weighted-Average expected return on plan assets for 2021 | 5.80% |  |
Pension Contributions [Abstract] |  |  |
Contributions to pension plan | $ 50.0 | $ 50.0 | $ 50.0
Company's common stock | 1.1 | 1.2 |
Deferred compensation liability | $ 31.0 | $ 22.8 |
Defined Benefit Plan, Plan Assets, Amount | $ 267.2 | 1,100.0 |
Minimum |  |  |
Pension Contributions [Abstract] |  |  |
Company's contribution to pension plan, percentage | 3.00% |  |
Maximum |  |  |
Pension Contributions [Abstract] |  |  |
Company's contribution to pension plan, percentage | 5.00% |  |
OPEB plans |  |  |
Pension Contributions [Abstract] |  |  |
Defined Benefit Plan, Accumulated Benefit Obligation | $ 10.5 | $ 9.5 |
Pension Plans |  |  |
Amounts Recognized in Accumulated Other Comprehensive Loss (Income) (Pre-Tax): |  |  |
Weighted-Average expected return on plan assets for 2021 | 5.52% | 4.08% | 4.91%
Pension Contributions [Abstract] |  |  |
Contributions to pension plan | $ 51.5 | $ 51.3 |
Defined Benefit Plan, Plan Assets, Amount | 1,161.6 | 1,055.3 | $ 1,382.7
Defined Benefit Plan, Accumulated Benefit Obligation | 1,173.3 | 1,131.0 |
Matching Contributions |  |  |
Pension Contributions [Abstract] |  |  |
Company's contribution to defined contribution plans | 45.2 | 44.3 | 38.2
Service Related Contributions |  |  |
Pension Contributions [Abstract] |  |  |
Company's contribution to defined contribution plans | $ 45.4 | $ 43.7 | $ 46.4

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- Definition The carrying amount of the liability as of the balance sheet date to an individual under a deferred compensation arrangement. This amount may be the result of periodic accruals made over the period of active employment, or reflect termination benefits resulting contractual terms or a death benefit. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Topic 710 -SubTopic 10 -Name Accounting Standards Codification -Section 30 -Paragraph 1 -Publisher FASB -URI https://asc.fasb.org//1943274/2147483043/710-10-30-1 + Details
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- Definition Amount of actuarial present value of benefits attributed to employee service rendered, excluding assumptions about future compensation level. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (e) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480506/715-20-50-1 + Details
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- Definition Weighted average rate of return on plan assets, reflecting average rate of earnings expected on existing plan assets and expected contributions, used to determine net periodic benefit cost of defined benefit plan. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 8 -Publisher FASB -URI https://asc.fasb.org//1943274/2147480506/715-20-50-8 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (k)(3) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480506/715-20-50-1 + Details
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