Note 11 - Equity Incentive Plan - Performance Stock Units (Details) - Performance Shares [Member] - $ / shares	3 Months Ended
Mar. 31, 2023	Mar. 31, 2022
Outstanding, shares (in shares)	117,897
Outstanding, weighted average grant date fair value (in dollars per share)		$ 34.98
Forfeited and cancelled, shares (in shares)	(117,897)
Forfeited and cancelled, weighted average grant date fair value (in dollars per share)		34.98
Outstanding, shares (in shares)	0
Outstanding, weighted average grant date fair value (in dollars per share)		$ 0

The number of equity-based payment instruments, excluding stock (or unit) options, that were forfeited during the reporting period.

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- Definition

Weighted average fair value as of the grant date of equity-based award plans other than stock (unit) option plans that were not exercised or put into effect as a result of the occurrence of a terminating event.

+ References

+ Details

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- Definition

The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (c)(2)(i)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480429/718-10-50-2

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (c)(2)(ii)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480429/718-10-50-2

+ Details

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- Definition

Per share or unit weighted-average fair value of nonvested award under share-based payment arrangement. Excludes share and unit options.

+ References

+ Details

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- Details

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