Pension and Other Postretirement Benefit Plans - Benefit Payments Expected to be Paid (Details) $ in Thousands	Dec. 31, 2021 USD ($)
Retirement Plan [Member]
2022	$ 1,273
2023	1,206
2024	1,197
2025	1,188
2026	1,186
2027 - 2031	5,943
Other Postretirement Benefits Plan [Member]
2022	251
2023	261
2024	298
2025	323
2026	343
2027 - 2031	2,189
Directors' Plan [Member]
2022	288
2023	256
2024	220
2025	192
2026	192
2027 - 2031	$ 592

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

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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