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Employee Postretirement Benefits - Assumptions Used to Determine Benefit Obligations (Details)	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Pension Plan
Defined Benefit Plan Disclosure [Line Items]
Discount Rate	3.03%	2.78%
Pension Plan | Participants to Age 39
Defined Benefit Plan Disclosure [Line Items]
Rate of Increase in Future Compensation	4.50%	4.50%
Pension Plan | Participants Ages 40 to 49
Defined Benefit Plan Disclosure [Line Items]
Rate of Increase in Future Compensation	3.50%	3.50%
Pension Plan | Participants Age 50 and Older
Defined Benefit Plan Disclosure [Line Items]
Rate of Increase in Future Compensation	2.75%	2.75%
Executive Survivor and Supplemental Retirement Plan
Defined Benefit Plan Disclosure [Line Items]
Discount Rate	2.93%	2.61%
Rate of Increase in Future Compensation	3.00%	3.00%
Other Postretirement Benefits Plan
Defined Benefit Plan Disclosure [Line Items]
Discount Rate	3.01%	2.75%
Healthcare Cost Immediate Trend Rate	6.16%	6.44%
Healthcare Cost Ultimate Trend Rate	4.50%	4.50%
Year the Rate Reaches the Ultimate Trend Rate	2038	2038

X

- 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

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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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+ References

No definition available.

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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

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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

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Year ultimate health care cost trend rate is expected to be reached, in YYYY format.

+ 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

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