Note 16 - Fair Value Measurements - Fair Value of Assets Measured on Recurring Basis, Unobservable Input Reconciliation (Details) $ in Thousands	Dec. 31, 2022 USD ($)	Dec. 31, 2021 USD ($)
Valuation Technique, Pricing Model [Member]
Impaired mortgage servicing rights		$ 0
Measurement Input, Discount Rate [Member] \| Valuation Technique, Pricing Model [Member] \| Minimum [Member]
Mortgage servicing rights, measurement input		0.000
Measurement Input, Discount Rate [Member] \| Valuation Technique, Pricing Model [Member] \| Maximum [Member]
Mortgage servicing rights, measurement input		0.120
Measurement Input, Discount Rate [Member] \| Valuation Technique, Pricing Model [Member] \| Weighted Average [Member]
Mortgage servicing rights, measurement input		0.102
Measurement Input, Discount Rate [Member] \| Valuation, Market Approach [Member]
Real estate owned	$ 145	$ 148
Measurement Input, Discount Rate [Member] \| Valuation, Market Approach [Member] \| Minimum [Member]
Real estate owned measurement input	0.348	0.348
Measurement Input, Discount Rate [Member] \| Valuation, Market Approach [Member] \| Maximum [Member]
Real estate owned measurement input	0.348	0.348
Measurement Input, Discount Rate [Member] \| Valuation, Market Approach [Member] \| Weighted Average [Member]
Real estate owned measurement input	0.348	0.348
Measurement Input, Prepayment Rate [Member] \| Valuation Technique, Pricing Model [Member] \| Minimum [Member]
Mortgage servicing rights, measurement input		0.098
Measurement Input, Prepayment Rate [Member] \| Valuation Technique, Pricing Model [Member] \| Maximum [Member]
Mortgage servicing rights, measurement input		0.434
Measurement Input, Prepayment Rate [Member] \| Valuation Technique, Pricing Model [Member] \| Weighted Average [Member]
Mortgage servicing rights, measurement input		0.118
Measurement Input, Cost to Service [Member] \| Valuation Technique, Pricing Model [Member] \| Minimum [Member]
Mortgage servicing rights, measurement input		84.06
Measurement Input, Cost to Service [Member] \| Valuation Technique, Pricing Model [Member] \| Maximum [Member]
Mortgage servicing rights, measurement input		839.53
Measurement Input, Cost to Service [Member] \| Valuation Technique, Pricing Model [Member] \| Weighted Average [Member]
Mortgage servicing rights, measurement input		108.37
Mortgage Derivative [Member] \| Pull Through Rate [Member] \| Valuation Technique, Pricing Model [Member]
Mortgage banking derivatives, fair value	$ (994)	$ (4,369)
Mortgage banking derivatives, fair value	$ 994	$ 4,369
Mortgage Derivative [Member] \| Pull Through Rate [Member] \| Valuation Technique, Pricing Model [Member] \| Minimum [Member]
Mortgage banking derivatives, measurement input	0.206	0.260
Mortgage Derivative [Member] \| Pull Through Rate [Member] \| Valuation Technique, Pricing Model [Member] \| Maximum [Member]
Mortgage banking derivatives, measurement input	1.000	0.998
Mortgage Derivative [Member] \| Pull Through Rate [Member] \| Valuation Technique, Pricing Model [Member] \| Weighted Average [Member]
Mortgage banking derivatives, measurement input	0.892	0.882

Value of input used to measure derivative asset.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (bbb)(2)
-URI https://asc.fasb.org/extlink&oid=126976982&loc=d3e19207-110258

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Balance Type:	na
Period Type:	instant

- Definition

Fair value, after the effects of master netting arrangements, of a financial asset or other 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 assets 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 55
-Paragraph 10
-URI https://asc.fasb.org/extlink&oid=99393222&loc=SL20226008-175313

Reference 2: 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

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/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

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Value of input used to measure real estate owned by financial institution by financial institution which is not directly related to its business.

+ References

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:decimalItemType
Balance Type:	na
Period Type:	instant

- Definition

Value of input used to measure servicing asset.

+ References

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:decimalItemType
Balance Type:	na
Period Type:	instant

- Definition

The fair value of impaired mortgage servicing rights.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
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- Definition

Represents fair value disclosure of real estate owned.

+ References

No definition available.

+ Details

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- Details

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- Details

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