Note 8 - Employee Benefit Plans (Details Textual) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020
Defined Contribution Plan, Cost	$ 1.0	$ 0.9
Defined Benefit Plan, Expected Future Employer Contributions, Next Fiscal Year	1.1
Defined Benefit Plan, Expected Future Benefit Payment, Year One	0.7
Defined Benefit Plan, Expected Future Benefit Payment, Year Two	0.8
Defined Benefit Plan, Expected Future Benefit Payment, Year Three	0.7
Defined Benefit Plan, Expected Future Benefit Payment, Year Four	0.9
Defined Benefit Plan, Expected Future Benefit Payment, Year Five	1.0
Defined Benefit Plan, Expected Future Benefit Payment, after Year Five for Next Five Years	$ 4.8

Amount of benefit for defined benefit plan expected to be paid in five fiscal years after fifth fiscal year following current fiscal year.

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- Definition

Amount of benefit for defined benefit plan expected to be paid in next fiscal year following current fiscal year.

+ References

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- Definition

Amount of benefit for defined benefit plan expected to be paid in fifth fiscal year following current fiscal year.

+ References

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- Definition

Amount of benefit for defined benefit plan expected to be paid in fourth fiscal year following current fiscal year.

+ References

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- Definition

Amount of benefit for defined benefit plan expected to be paid in third fiscal year following current fiscal year.

+ References

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Amount of benefit for defined benefit plan expected to be paid in second fiscal year following current fiscal year.

+ References

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- Definition

Amount of contribution expected to be received by defined benefit plan from employer in next fiscal year following current fiscal year.

+ References

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

Reference 2: http://www.xbrl.org/2003/role/exampleRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 55
-Paragraph 18
-URI http://asc.fasb.org/extlink&oid=123450688&loc=d3e4587-114921

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Amount of cost for defined contribution plan.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 70
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=49170846&loc=d3e28014-114942

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