Pension and Other Postretirement Benefit Plans - Benefit Payments Expected to be Paid (Details) $ in Thousands	Dec. 31, 2023 USD ($)
Retirement Plan [Member]
2024	$ 1,247
2025	1,238
2026	1,237
2027	1,239
2028	1,232
2029 - 2033	6,052
Other Postretirement Benefits Plan [Member]
2024	255
2025	297
2026	347
2027	399
2028	414
2029 - 2033	2,751
Directors' Plan [Member]
2024	124
2025	96
2026	96
2027	96
2028	96
2029 - 2033	$ 444

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
-Topic 715
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (f)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480506/715-20-50-1

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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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