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Pension and Other Postretirement Benefits - Pension Plan Asset Allocation (Details)	Dec. 31, 2021	Dec. 31, 2020
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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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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