Retirement Benefits (Estimated future benefit payments) (Details) $ in Thousands	Dec. 31, 2021 USD ($)
Pension Benefits
Estimated future benefit payments
2022	$ 13,553
2023	15,097
2024	16,801
2025	16,182
2026	18,073
Years 2027-2031	102,198
Postretirement Medical Benefits
Estimated future benefit payments
2022	1,768
2023	1,775
2024	1,755
2025	1,734
2026	1,713
Years 2027-2031	$ 8,362

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

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

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

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

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

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