Retirement Benefits (Future Postretirement Health Care and Life Insurance Benefit Payments) (Details) - Postretirement Health Care and Life Insurance Benefit Plans $ in Thousands	Dec. 31, 2021 USD ($)
Pension Postretirement And Other Retirement Plans [Line Items]
Before Medicare Subsidy 2022	$ 892
Before Medicare Subsidy 2023	850
Before Medicare Subsidy 2024	816
Before Medicare Subsidy 2025	775
Before Medicare Subsidy 2026	741
Before Medicare Subsidy 2026-2030	3,204
After Medicare Subsidy, 2022	892
After Medicare Subsidy, 2023	850
After Medicare Subsidy, 2024	816
After Medicare Subsidy, 2025	775
After Medicare Subsidy, 2026	741
After Medicare Subsidy 2026-2030	$ 3,204

Defined Benefit Plan Expected Future Benefit Payments After Medicare Subsidy Five Fiscal Years Thereafter

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- Definition

Defined Benefit Plan Expected Future Benefit Payments After Medicare Subsidy Next Twelve Months

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- Definition

Defined Benefit Plan Expected Future Benefit Payments After Medicare Subsidy Year Five

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- Definition

Defined Benefit Plan Expected Future Benefit Payments After Medicare Subsidy Year Four

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- Definition

Defined Benefit Plan Expected Future Benefit Payments After Medicare Subsidy Year Three

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- Definition

Defined Benefit Plan Expected Future Benefit Payments After Medicare Subsidy Year Two

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- Definition

Pension Postretirement And Other Retirement Plans [Line Items]

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- Definition

Amount of benefit for defined benefit plan expected to be paid in five fiscal years after fifth fiscal year following current fiscal year.

+ 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 (f)
-URI http://asc.fasb.org/extlink&oid=123447040&loc=d3e1928-114920

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- Definition

Amount of benefit for defined benefit plan expected to be paid in next fiscal year following current fiscal year.

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- Definition

Amount of benefit for defined benefit plan expected to be paid in fifth fiscal year following current fiscal year.

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- Definition

Amount of benefit for defined benefit plan expected to be paid in fourth fiscal year following current fiscal year.

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- Definition

Amount of benefit for defined benefit plan expected to be paid in third fiscal year following current fiscal year.

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- Definition

Amount of benefit for defined benefit plan expected to be paid in second fiscal year following current fiscal year.

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