Note 9 - Employee Retirement Plans - Assumptions of Net Periodic Costs (Details) - Pension Plan [Member]	12 Months Ended
Dec. 31, 2022	Dec. 31, 2021
Discount rate	2.90%	2.50%
Expected long-term rate of return on assets	5.50%	4.00%

Weighted average rate of return on plan assets, reflecting average rate of earnings expected on existing plan assets and expected contributions, used to determine net periodic benefit cost of defined benefit plan.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (k)(3)
-URI https://asc.fasb.org/extlink&oid=123447040&loc=d3e1928-114920

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 8
-URI https://asc.fasb.org/extlink&oid=123447040&loc=d3e2919-114920

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Namespace Prefix:	us-gaap_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration