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Pension and Other Postretirement Benefits - Pension Plan Asset Allocation (Details) | Dec. 31, 2021 | Dec. 31, 2020
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Defined Benefit Plan Disclosure [Line Items] |  |
Target allocation percentage of assets | 100.00% |
Actual plan asset allocations | 100.00% | 100.00%
U.S. equities |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Target allocation percentage of assets | 0.00% |
Actual plan asset allocations | 0.00% | 31.00%
International equities |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Target allocation percentage of assets | 0.00% |
Actual plan asset allocations | 0.00% | 27.00%
Fixed income |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Target allocation percentage of assets | 0.00% |
Actual plan asset allocations | 0.00% | 42.00%
Global equity |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Target allocation percentage of assets | 52.00% |
Actual plan asset allocations | 51.00% | 0.00%
Diversified credit |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Target allocation percentage of assets | 15.00% |
Actual plan asset allocations | 15.00% | 0.00%
Real assets |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Target allocation percentage of assets | 8.00% |
Actual plan asset allocations | 9.00% | 0.00%
Liability hedging assets |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Target allocation percentage of assets | 25.00% |
Actual plan asset allocations | 25.00% | 0.00%
Cash |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Target allocation percentage of assets | 0.00% |
Actual plan asset allocations | 0.00% | 0.00%

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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. + References Reference 1: http://www.xbrl.org/2003/role/exampleRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 55 -Paragraph 17 -URI http://asc.fasb.org/extlink&oid=123450688&loc=d3e4179-114921 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (d)(i) -URI http://asc.fasb.org/extlink&oid=123447040&loc=d3e1928-114920 + Details
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- Definition Percentage of actual investment allocation to total plan assets. Includes, but is not limited to, percentage on weighted-average basis if more than one plan. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (d)(i) -URI http://asc.fasb.org/extlink&oid=123447040&loc=d3e1928-114920 + Details
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