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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

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- 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 + Details
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- Definition Fair value, after the effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes liabilities not subject to a master netting arrangement and not elected to be offset. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 20 -Section 50 -Paragraph 3 -Subparagraph (c) -URI https://asc.fasb.org/extlink&oid=51824906&loc=SL20225862-175312 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 20 -Section 55 -Paragraph 10 -URI https://asc.fasb.org/extlink&oid=99393222&loc=SL20226008-175313 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 825 -SubTopic 10 -Section 50 -Paragraph 10 -URI https://asc.fasb.org/extlink&oid=123594938&loc=d3e13433-108611 Reference 4: http://www.xbrl.org/2003/role/exampleRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 20 -Section 55 -Paragraph 22 -URI https://asc.fasb.org/extlink&oid=99393222&loc=SL20226052-175313 + Details
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