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Note 19 - Fair Value Measurements - Balances of Assets Measured at Fair Value on Recurring Basis (Details) - USD ($) $ in Thousands	Dec. 31, 2022	Sep. 30, 2022	Dec. 31, 2021
Fair value, available for sale securities	$ 162,907	$ 74,400	$ 289,495
Fair Value, Inputs, Level 1 [Member]
Fair value, available for sale securities	0
Fair Value, Inputs, Level 2 [Member]
Fair value, available for sale securities	0
Fair Value, Inputs, Level 3 [Member]
Fair value, available for sale securities	0
Fair Value, Recurring [Member]
Fair value, available for sale securities	162,907		289,495
Derivatives - cash flow hedges	2,679		941
Assets, Fair Value	165,586		290,436
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 1 [Member]
Fair value, available for sale securities	0		0
Derivatives - cash flow hedges	0		0
Assets, Fair Value	0		0
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 2 [Member]
Fair value, available for sale securities	162,907		289,495
Derivatives - cash flow hedges	2,679		941
Assets, Fair Value	165,586		290,436
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 3 [Member]
Fair value, available for sale securities	0		0
Derivatives - cash flow hedges	0		0
Assets, Fair Value	0		0
US Treasury Securities [Member]
Fair value, available for sale securities	11,229		39,658
US Treasury Securities [Member] | Fair Value, Recurring [Member]
Fair value, available for sale securities	11,229		39,658
US Treasury Securities [Member] | Fair Value, Recurring [Member] | Fair Value, Inputs, Level 1 [Member]
Fair value, available for sale securities	0		0
US Treasury Securities [Member] | Fair Value, Recurring [Member] | Fair Value, Inputs, Level 2 [Member]
Fair value, available for sale securities	11,229		39,658
US Treasury Securities [Member] | Fair Value, Recurring [Member] | Fair Value, Inputs, Level 3 [Member]
Fair value, available for sale securities	0		0
US Agency and Mortgage-backed Securities [Member]
Fair value, available for sale securities	96,918		176,379
US Agency and Mortgage-backed Securities [Member] | Fair Value, Recurring [Member]
Fair value, available for sale securities	96,918		176,379
US Agency and Mortgage-backed Securities [Member] | Fair Value, Recurring [Member] | Fair Value, Inputs, Level 1 [Member]
Fair value, available for sale securities	0		0
US Agency and Mortgage-backed Securities [Member] | Fair Value, Recurring [Member] | Fair Value, Inputs, Level 2 [Member]
Fair value, available for sale securities	96,918		176,379
US Agency and Mortgage-backed Securities [Member] | Fair Value, Recurring [Member] | Fair Value, Inputs, Level 3 [Member]
Fair value, available for sale securities	0		0
Municipal Bonds [Member] | Fair Value, Recurring [Member]
Fair value, available for sale securities	54,760		71,438
Municipal Bonds [Member] | Fair Value, Recurring [Member] | Fair Value, Inputs, Level 1 [Member]
Fair value, available for sale securities	0		0
Municipal Bonds [Member] | Fair Value, Recurring [Member] | Fair Value, Inputs, Level 2 [Member]
Fair value, available for sale securities	54,760		71,438
Municipal Bonds [Member] | Fair Value, Recurring [Member] | Fair Value, Inputs, Level 3 [Member]
Fair value, available for sale securities	$ 0		0
Corporate Debt Securities [Member]
Fair value, available for sale securities			2,020
Corporate Debt Securities [Member] | Fair Value, Recurring [Member]
Fair value, available for sale securities			2,020
Corporate Debt Securities [Member] | Fair Value, Recurring [Member] | Fair Value, Inputs, Level 1 [Member]
Fair value, available for sale securities			0
Corporate Debt Securities [Member] | Fair Value, Recurring [Member] | Fair Value, Inputs, Level 2 [Member]
Fair value, available for sale securities			2,020
Corporate Debt Securities [Member] | Fair Value, Recurring [Member] | Fair Value, Inputs, Level 3 [Member]
Fair value, available for sale securities			$ 0

X

- Definition

Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)
-URI https://asc.fasb.org/extlink&oid=126976982&loc=d3e19207-110258

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X

- Definition

Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(6))
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-Name Accounting Standards Codification
-Topic 326
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+ References

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-Topic 210
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-Section 50
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