Note 13 - Retirement Benefit Plans - Estimated Future Benefit Payments (Details) $ in Thousands	Dec. 31, 2021 USD ($)
2022, estimated future benefit payment	$ 143
2023, estimated future benefit payment	143
2024, estimated future benefit payment	142
2025, estimated future benefit payment	142
2026, estimated future benefit payment	135
Years 2027-2031, estimated future benefit payment	$ 534

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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