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Employee Postretirement Benefits - Asset Allocation Ranges By Asset Class and PBO Funded Status (Details) - Pension Plan	Dec. 31, 2021	Dec. 31, 2020
Defined Benefit Plan Disclosure [Line Items]
Actual Allocation	100.00%	100.00%
Return Enhancement
Defined Benefit Plan Disclosure [Line Items]
Actual Allocation	47.00%	58.00%
Return Enhancement | 20 - 60% | Minimum
Defined Benefit Plan Disclosure [Line Items]
Permitted Range	20.00%
Return Enhancement | 20 - 60% | Maximum
Defined Benefit Plan Disclosure [Line Items]
Permitted Range	60.00%
Risk Management
Defined Benefit Plan Disclosure [Line Items]
Actual Allocation	50.00%	39.00%
Risk Management | 40 - 80% | Minimum
Defined Benefit Plan Disclosure [Line Items]
Permitted Range	40.00%
Risk Management | 40 - 80% | Maximum
Defined Benefit Plan Disclosure [Line Items]
Permitted Range	80.00%
Alternatives
Defined Benefit Plan Disclosure [Line Items]
Actual Allocation	3.00%	3.00%
Alternatives | 0 - 20% | Minimum
Defined Benefit Plan Disclosure [Line Items]
Permitted Range	0.00%
Alternatives | 0 - 20% | Maximum
Defined Benefit Plan Disclosure [Line Items]
Permitted Range	20.00%

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- Definition

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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

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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

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