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Postretirement Benefits Other Than Pensions - Actuarial Assumptions of OPEB Expense (Details) - Other Postretirement Benefit Plan, Defined Benefit | 12 Months Ended
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Dec. 31, 2021 | Dec. 31, 2020 | Dec. 31, 2019
Defined Benefit Plan Disclosure [Line Items] |  |  |
Weighted-average Discount Rate | 1.99% | 2.96% | 4.08%
Service Cost Discount Rate | 2.06% | 2.94% | 4.16%
Interest Cost Discount Rate | 1.19% | 2.47% | 3.69%
Rate of Increase in Future Compensation Levels | 2.20% | 2.20% | 2.20%

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- Definition Defined Benefit Plan, Assumptions Used Calculating Net Periodic Benefit Cost, Interest Cost Discount Rate + References No definition available. + Details
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- Definition Defined Benefit Plan, Assumptions Used in Calculating Net Periodic Benefit Cost, Service Cost Discount Rate + References No definition available. + Details
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- Definition Weighted average rate for present value of future retirement benefits cash flows, used to determine net periodic benefit cost of defined benefit plan. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (k)(1) -URI http://asc.fasb.org/extlink&oid=123447040&loc=d3e1928-114920 + Details
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- Definition Weighted average rate of compensation increase used to determine net periodic benefit cost of defined benefit plan. Plan includes, but is not limited to, pay-related defined benefit plan. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (k)(2) -URI http://asc.fasb.org/extlink&oid=123447040&loc=d3e1928-114920 + Details
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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. + References No definition available. + Details
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- Details
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