v3.22.0.1

Pension and Other Postretirement Benefits - Plan Asset Allocations (Details) - Pension benefits​	Dec. 31, 2021	Dec. 31, 2020
Defined Benefit Plan Disclosure [Line Items]
Plan asset, weighted average asset allocations	100.00%	100.00%
Equities
Defined Benefit Plan Disclosure [Line Items]
Plan asset, weighted average asset allocations	31.00%	20.00%
Equities | Maximum
Defined Benefit Plan Disclosure [Line Items]
Policy maximum	40.00%
Fixed income
Defined Benefit Plan Disclosure [Line Items]
Plan asset, weighted average asset allocations	56.00%	51.00%
Fixed income | Maximum
Defined Benefit Plan Disclosure [Line Items]
Policy maximum	100.00%
Other investments
Defined Benefit Plan Disclosure [Line Items]
Plan asset, weighted average asset allocations	13.00%	29.00%
Other investments | Maximum
Defined Benefit Plan Disclosure [Line Items]
Policy maximum	30.00%

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+ References

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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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- 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

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