Employee Benefits - Assumptions Used to Determine Benefit Obligation (Details)	Dec. 31, 2021	Dec. 31, 2020
Salaried VEBA
Defined Benefit Plan Disclosure [Line Items]
Discount rate	2.49%	2.05%
Pension Plan
Defined Benefit Plan Disclosure [Line Items]
Discount rate	2.90%	2.50%
Rate of compensation increase	2.74%	3.00%
Other Postretirement Benefits Plan
Defined Benefit Plan Disclosure [Line Items]
Discount rate	2.64%

Weighted average rate for present value of future retirement benefits cash flows, used to determine benefit obligation of defined benefit plan.

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

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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

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- Definition

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+ References

No definition available.

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