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Pension and Other Postretirement Benefit Plans - Assumptions Used to Determine Benefit Obligation and Net Periodic Benefit Costs (Details) | 12 Months Ended
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Dec. 31, 2021 | Dec. 31, 2020 | Dec. 31, 2019
Pension [Member] |  |  |  |
Defined Benefit Plans and Other Postretirement Benefit Plans [Line Items] |  |  |  |
Defined Benefit Plan, Assumptions Used Calculating Net Periodic Benefit Costs, Future Period |  | 6.00% |  |
Assumptions Used to Determine Benefit Obligation [Abstract] |  |  |  |
Discount Rate |  | 3.05% | 2.62% |
Rate of Compensation Increase |  | 3.58% | 3.61% |
Assumptions Used to Determine Net Periodic Benefit Costs [Abstract] |  |  |  |
Defined Benefit Plan, Assumptions Used Calculating Net Periodic Benefit Cost, Discount Rate |  | 2.87% | 3.52% | 4.67%
Expected Long-Term Return on Plan Assets | [1] | 6.50% | 6.75% | 7.25%
Rate of Compensation Increase |  | 3.62% | 4.06% | 4.04%
Postretirement Health and Life [Member] |  |  |  |
Assumptions Used to Determine Benefit Obligation [Abstract] |  |  |  |
Discount Rate |  | 3.09% | 2.70% |
Health Care Trend Rates [Abstract] |  |  |  |
Trend Rate |  | 5.66% | 5.81% |
Ultimate Trend Rate |  | 4.50% | 4.50% |
Year Ultimate Trend Rate Effective |  | 2038 | 2038 |
Assumptions Used to Determine Net Periodic Benefit Costs [Abstract] |  |  |  |
Defined Benefit Plan, Assumptions Used Calculating Net Periodic Benefit Cost, Discount Rate |  | 2.70% | 3.45% | 4.47%
Expected Long-Term Return on Plan Assets | [1] | 5.85% | 6.08% | 6.51%
Postretirement Health and Life [Member] | Minimum [Member] |  |  |  |
Defined Benefit Plans and Other Postretirement Benefit Plans [Line Items] |  |  |  |
Defined Benefit Plan, Assumptions Used Calculating Net Periodic Benefit Costs, Future Period |  | 4.80% |  |
Postretirement Health and Life [Member] | Maximum [Member] |  |  |  |
Defined Benefit Plans and Other Postretirement Benefit Plans [Line Items] |  |  |  |
Defined Benefit Plan, Assumptions Used Calculating Net Periodic Benefit Costs, Future Period |  | 6.00% |  |
[1] | The expected long-term rates of return used to determine net periodic benefit expense for 2022 have been reduced to 6.00 percent for pension expense and 4.80 percent to 6.00 percent for postretirement health and life expense.

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- Definition Defined Benefit Plan, Assumptions Used Calculating Net Periodic Benefit Costs, Future Period + 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 benefit obligation 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 increase of compensation, used to determine benefit obligation 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 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 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 -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (k)(3) -URI http://asc.fasb.org/extlink&oid=123447040&loc=d3e1928-114920 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 8 -URI http://asc.fasb.org/extlink&oid=123447040&loc=d3e2919-114920 + 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 Assumed rate, for next fiscal year, based on annual change in cost of health care cost benefits used to measure expected cost of benefits covered by defined benefit postretirement plan. Factors include, but are not limited to, estimate of health care inflation, change in health care utilization or delivery pattern, technological advances, and change in health status of participant. Excludes factors for change in composition of plan population by age and dependency status. + 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 (l) -URI http://asc.fasb.org/extlink&oid=123447040&loc=d3e1928-114920 + Details
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- Definition Ultimate trend rate for health care cost for defined benefit postretirement 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 (l) -URI http://asc.fasb.org/extlink&oid=123447040&loc=d3e1928-114920 + Details
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