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Note 15 - Stock Based Compensation - Stock Options Outstanding By Exercise Price Range (Details)	12 Months Ended
	Dec. 31, 2022 $ / shares shares
Exercise Price Range One [Member]
Exercise price of stock options (in dollars per share) | $ / shares	$ 27.25
Number of options outstanding at year-end (in shares)	12,000
Number of options exercisable at year-end (in shares)	12,000
Average remaining contractual life (Year)	6 years 5 months 1 day
Exercise Price Range Two [Member]
Exercise price of stock options (in dollars per share) | $ / shares	$ 25.65
Number of options outstanding at year-end (in shares)	3,000
Number of options exercisable at year-end (in shares)	3,000
Average remaining contractual life (Year)	5 years 6 months
Exercise Price Range Three [Member]
Exercise price of stock options (in dollars per share) | $ / shares	$ 20.86
Number of options outstanding at year-end (in shares)	3,306
Number of options exercisable at year-end (in shares)	3,306
Average remaining contractual life (Year)	4 years 4 months 6 days
Exercise Price Range Four [Member]
Exercise price of stock options (in dollars per share) | $ / shares	$ 21.13
Number of options outstanding at year-end (in shares)	2,325
Number of options exercisable at year-end (in shares)	2,325
Average remaining contractual life (Year)	3 years

X

- Definition

The number of shares reserved for issuance pertaining to the outstanding exercisable stock options as of the balance sheet date in the customized range of exercise prices for which the market and performance vesting condition has been satisfied.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(iii)
-URI https://asc.fasb.org/extlink&oid=128089324&loc=d3e5070-113901

+ Details

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Namespace Prefix:	us-gaap_
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Balance Type:	na
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X

- Definition

The number of shares reserved for issuance pertaining to the outstanding stock options as of the balance sheet date for all option plans in the customized range of exercise prices.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)(i)-(ii)
-URI https://asc.fasb.org/extlink&oid=128089324&loc=d3e5070-113901

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X

- Definition

The weighted average price as of the balance sheet date at which grantees could acquire the underlying shares with respect to all outstanding stock options which are in the customized range of exercise prices.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)(i)-(ii)
-URI https://asc.fasb.org/extlink&oid=128089324&loc=d3e5070-113901

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X

- Definition

Weighted average remaining contractual term of outstanding stock options, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (e)(1)
-URI https://asc.fasb.org/extlink&oid=128089324&loc=d3e5070-113901

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