Note 8 - Benefit Plans - Projected Benefit Payments (Details) $ in Thousands	Dec. 31, 2020 USD ($)
2021	$ 1,788
2022	2,203
2023	1,939
2024	1,898
2025	1,869
2026-2030	8,427
Pension Plan [Member]
2021	1,686
2022	1,028
2023	1,351
2024	1,317
2025	1,297
2026-2030	4,651
Supplemental Employee Retirement Plan [Member]
2021	102
2022	1,175
2023	588
2024	581
2025	572
2026-2030	$ 3,776

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=118255775&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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