Note 18 - Employee Benefit Plans - Weighted Average Asset Allocation by Asset Category (Details)	Dec. 31, 2021	Dec. 31, 2020
Asset allocations	100.00%	100.00%
Fixed Income Securities [Member]
Asset allocations	56.50%	65.60%
Defined Benefit Plan, Equity Securities [Member]
Asset allocations	22.90%	31.50%
Defined Benefit Plan, Cash and Accrued Income [Member]
Asset allocations	20.60%	2.90%

Percentage of actual investment allocation to total plan assets. Includes, but is not limited to, percentage on weighted-average basis if more than one plan.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (d)(i)
-URI http://asc.fasb.org/extlink&oid=123447040&loc=d3e1928-114920

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