Note 12 - Borrowings and Financing Activities - FHLB Advances (Details) $ in Thousands	12 Months Ended
Dec. 31, 2020 USD ($)	Dec. 31, 2019 USD ($)
Federal Home Loan Bank Advances
Federal Home Loan Bank, Advances [Line Items]
Advances from Federal Home Loan Banks	$ 176,483	$ 134,875
Federal Home Loan Bank, Advances, Weighted Average Interest Rate	1.12%
Federal Home Loan Bank, Advances, Maturity Period, Fixed Rate	90 days
Federal Home Loan Bank Certificates and Obligations (FHLB) [Member] \| Minimum
Federal Home Loan Bank, Advances [Line Items]
Federal Home Loan Bank, Ratio of Market Value of Collateral to Advances	1.03
Federal Home Loan Bank Certificates and Obligations (FHLB) [Member] \| Maximum
Federal Home Loan Bank, Advances [Line Items]
Federal Home Loan Bank, Ratio of Market Value of Collateral to Advances	1.11
Fixed-maturities available for sale \| Debt Securities
Federal Home Loan Bank, Advances [Line Items]
Investments serving as collateral for FHLB advances	$ 188,000	$ 143,100

The ratio of the market value of the collateralized eligible assets to the principal balance of the FHLB advances

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- Definition

Amount of borrowings as of the balance sheet date from the Federal Home Loan Bank, which are primarily used to cover shortages in the required reserve balance and liquidity shortages.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 470
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6479118&loc=d3e64650-112822

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- Definition

Amount of the collateral pledged in support of federal home loan bank advances outstanding.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 470
-Section 50
-Paragraph 3
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=75038535&loc=d3e64711-112823

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-Publisher FASB
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-Topic 942
-SubTopic 470
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6479118&loc=d3e64650-112822

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

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Maturity period on fixed rate advances made and reported by Federal Home Loan Bank (FHLBank), in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

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Weighted average interest rate on advances made and reported by Federal Home Loan Bank (FHLBank).

+ References

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