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Retirement Plans and Other Postretirement Benefits - Asset Allocation (Details) | Dec. 31, 2021
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Pension Benefits |
Defined Benefit Plan Disclosure [Line Items] |
Target Allocation | 100.00%
Actual Allocation | 100.00%
Pension Benefits | Long-term fixed income assets |
Defined Benefit Plan Disclosure [Line Items] |
Target Allocation | 80.00%
Actual Allocation | 79.00%
Pension Benefits | Return-generating assets |
Defined Benefit Plan Disclosure [Line Items] |
Target Allocation | 20.00%
Actual Allocation | 21.00%
Target Allocation | 20.00%
Pension Benefits | Equities in US and other developed markets |
Defined Benefit Plan Disclosure [Line Items] |
Target Allocation | 12.00%
Pension Benefits | Equities in emerging markets |
Defined Benefit Plan Disclosure [Line Items] |
Target Allocation | 4.00%
Pension Benefits | Alternative investments |
Defined Benefit Plan Disclosure [Line Items] |
Target Allocation | 4.00%
Other Benefits |
Defined Benefit Plan Disclosure [Line Items] |
Actual Allocation | 100.00%
Other Benefits | Long-term fixed income assets |
Defined Benefit Plan Disclosure [Line Items] |
Actual Allocation | 63.00%
Other Benefits | Return-generating assets |
Defined Benefit Plan Disclosure [Line Items] |
Actual Allocation | 37.00%

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