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Period of time between grant and maturity of financing receivable.

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Lending threshold requiring additional loan review.

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The maximum term of low income housing tax credit permanent loans.

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Interest, dividends, rents, ancillary and other revenues earned but not yet received by the entity on its investments.

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Amount of allowance for credit loss for debt security measured at amortized cost (held-to-maturity).

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Amount of allowance for credit loss on financing receivable. Excludes allowance for financing receivable covered under loss sharing agreement.

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Note 1 - SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Details)	3 Months Ended
	Mar. 31, 2021 USD ($) subsidiary segment	Dec. 31, 2021 USD ($)	Jan. 01, 2021 USD ($)	Dec. 31, 2020 USD ($)	Mar. 31, 2020 USD ($)	Dec. 31, 2019 USD ($)
Retained earnings	$ 316,900,000			$ 300,804,000
Less allowance	81,831,000	$ 84,376,000		84,376,000	$ 42,233,000	$ 36,001,000
Debt Securities, Held-to-maturity, Allowance for Credit Loss	$ 174,000
Number of subsidiaries commercial banks \| subsidiary	4
Number of portfolio segments \| segment	8
Financing Receivable, Lines of Credit Maximum Term	1 year
Lending Threshold Requiring Additional Loan Review	$ 1,000,000
Accrued Investment Income Receivable	19,000,000
Cumulative Effect, Period of Adoption, Adjustment [Member]
Less allowance			$ (8,102,000)
Debt Securities, Held-to-maturity, Allowance for Credit Loss			183,000
Off-Balance Sheet, Credit Loss, Liability			9,117,000
Accounting Standards Update 2016-13
Retained earnings	937,000
Less allowance				(8,102,000)
Debt Securities, Held-to-maturity, Allowance for Credit Loss	$ 183,000
Accounting Standards Update 2016-13 \| Cumulative Effect, Period of Adoption, Adjustment [Member]
Retained earnings			937,000
Less allowance			(8,100,000)
Debt Securities, Held-to-maturity, Allowance for Credit Loss			183,000
Off-Balance Sheet, Credit Loss, Liability			9,100,000
Subsidiaries [Member] \| Fixed Rate Residential Mortgage [Member]
Financing Receivable, Term	15 years
Commercial Portfolio Segment [Member]
Less allowance	$ 36,714,000	$ 35,421,000		35,421,000	$ 18,151,000	$ 16,072,000
Financing Receivable, Term Loans, Generally Maximum Term	7 years
Commercial Portfolio Segment [Member] \| Cumulative Effect, Period of Adoption, Adjustment [Member]
Less allowance			$ (35,421,000)
Commercial Portfolio Segment [Member] \| Accounting Standards Update 2016-13
Less allowance				$ (35,421,000)
Minimum
Financing Receivable, Lines of Credit Maximum Term	6 months
Residual Value Percent of Cost	3.00%
Minimum \| Subsidiaries [Member] \| Adjustable Rate Residential Mortgage [Member]
Financing Receivable, Term	1 year
Minimum \| Commercial Portfolio Segment [Member] \| Term Loan [Member]
Financing Receivable, Term	3 years
Maximum
Permanent loans term	20 years
Financing Receivable, Credit Weaknesses Borrowers, Term	365 days
Financing Receivable, Lines of Credit Maximum Term	1 year
Residual Value Percent of Cost	25.00%
Maximum \| Subsidiaries [Member] \| Adjustable Rate Residential Mortgage [Member]
Financing Receivable, Term	5 years
Maximum \| Commercial Portfolio Segment [Member] \| Term Loan [Member]
Financing Receivable, Term	5 years