Pension and Other Postretirement Benefits Plans - Assumptions Used to Determine Benefit Obligations (Details)	12 Months Ended
Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Postretirement Plans [Member]
Discount rate, net periodic benefit	2.58%	2.18%	3.00%
Initial	7.50%	7.50%	7.50%
Ultimate (year 2026)	5.00%	5.00%	5.00%
Retirement Plan [Member]
Discount rate, benefit obligation	4.93%	2.58%
Discount rate, net periodic benefit	2.58%	2.18%	3.00%
Defined Benefit Plan, Assumptions Used Calculating Net Periodic Benefit Cost, Expected Long-term Rate of Return on Plan Assets	4.25%	4.75%	4.75%
Rate of return on plan assets	4.25%	4.75%	4.75%
Other Postretirement Benefits Plan [Member]
Discount rate, benefit obligation	4.93%	2.58%
Initial	7.50%	7.50%
Ultimate (year 2026)	4.44%	5.00%
Directors' Plan [Member]
Discount rate, benefit obligation	4.93%	2.58%	2.18%
Discount rate, net periodic benefit	2.58%	2.18%	3.00%

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

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- Definition

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

+ References

+ Details

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- Definition

Weighted average rate of return on plan assets, reflecting average rate of earnings expected on existing plan assets and expected contributions, used to determine net periodic benefit cost 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)(3)
-URI https://asc.fasb.org/extlink&oid=123447040&loc=d3e1928-114920

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 8
-URI https://asc.fasb.org/extlink&oid=123447040&loc=d3e2919-114920

+ Details

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- Definition

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.

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- Definition

Ultimate trend rate for health care cost for defined benefit postretirement plan.

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+ Details

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