Pension and Other Postretirement Plans - Assumptions (Details)	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Defined Benefit Pension Plans
Weighted-average assumptions used to determine benefit obligations:
Discount rate	2.75%	2.25%	3.00%
Weighted-average assumptions used to determine net periodic benefit cost:
Discount rate	2.25%	3.00%	4.00%
Expected long-term return on plan assets	7.00%	7.00%	7.00%
Chairman and President Non-Qualified Defined Benefit Plans
Weighted-average assumptions used to determine benefit obligations:
Discount rate	2.75%	2.25%	3.00%
Rate of compensation increase	8.00%	8.00%
Weighted-average assumptions used to determine net periodic benefit cost:
Discount rate	2.25%	3.00%	4.00%
Rate of compensation increase	8.00%	8.00%	8.00%
Defined Benefit Postretirement Healthcare Plans
Weighted-average assumptions used to determine benefit obligations:
Discount rate	2.75%	2.25%	3.00%
Annual rate of increase in the per capita cost of covered health care benefits (in percentage)	7.50%
Decrease in annual rate of increase in the per capita cost of covered health care benefits (in percentage)	0.50%
Ultimate annual rate of increase in the per capita cost of covered health care benefits (in percentage)	5.00%
Weighted-average assumptions used to determine net periodic benefit cost:
Discount rate	2.25%	3.00%	4.00%

Defined Benefit Plan, Increase (Decrease) In Health Care Cost Trend Rate Assumed

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- Definition

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 increase of compensation, used to determine benefit obligation of defined benefit plan. Plan includes, but is not limited to, pay-related 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.

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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 http://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 http://asc.fasb.org/extlink&oid=123447040&loc=d3e2919-114920

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- Definition

Weighted average rate of compensation increase used to determine net periodic benefit cost of defined benefit plan. Plan includes, but is not limited to, pay-related defined benefit plan.

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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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