Note 3 - Securities (Details Textual) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2021 USD ($)	Sep. 30, 2020 USD ($)	Sep. 30, 2021 USD ($)	Sep. 30, 2020 USD ($)	Jun. 30, 2021 USD ($)	Dec. 31, 2020 USD ($)
Debt Securities, Available-for-sale, Restricted	$ 114,320		$ 114,320		$ 96,970
Debt Securities, Available-for-sale, Unrealized Loss Position, Number of Positions	87		87
Equity Securities, FV-NI, Cost	$ 400		$ 400			$ 400
Equity Securities, FV-NI, Total	424		424			$ 424
Equity Securities, FV-NI, Unrealized Gain (Loss), Total	0	$ 0	0	$ 0
Proceeds from Sale of Equity Securities, FV-NI	$ 0	$ 0	$ 0	$ 0

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

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 954
-SubTopic 210
-Section 45
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=120413173&loc=SL6242262-115580

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
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-Section 50
-Paragraph 1A
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Number of investments in debt securities measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in unrealized loss position, without allowance for credit loss. Includes beneficial interest in securitized financial asset.

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Cost of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI). Excludes equity method investment and investment in equity security without readily determinable fair value.

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Amount of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

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Amount of unrealized gain (loss) on investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

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Amount of cash inflow from sale of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI), classified as investing activity.

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