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Note 8 - Loans and Related Allowance for Loan and Lease Losses (Details Textual) Pure in Thousands	3 Months Ended		12 Months Ended
	Mar. 31, 2022 USD ($)	Mar. 31, 2021 USD ($)	Dec. 31, 2021 USD ($)
Loans and Leases Receivable, Deferred Income	$ 2,800,000		$ 3,600,000
Financing Receivable, Troubled Debt Restructuring	2,400,000		2,600,000
Financing Receivable, Allowance for Credit Loss, Writeoff	$ 159,000		150,000
Number of Days Past Due (Day)	90 days
Loans and Leases Receivable, Impaired, Interest Lost on Nonaccrual Loans	$ 64,000	$ 124,000
Financing Receivable, Troubled Debt Restructuring, Subsequent Default, Number of Contracts	0	0
Threshold For Loans Evaluated For Impairment [Member]
Loans and Leases Receivable, before Fees, Gross	$ 750,000
Small Business Administration (SBA), CARES Act, Paycheck Protection Program [Member]
Loans and Leases Receivable, Deferred Income	$ 602,000		$ 1,300,000

X

- Definition

The number of days past due.

+ References

No definition available.

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- Definition

Amount of writeoff of financing receivable, charged against allowance for credit loss.

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Amount of financing receivable modified as troubled debt restructuring.

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Number of financing receivable contracts modified as troubled debt restructuring within previous 12 months, with subsequent payment default.

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- Definition

Amount, before allowance and fees, of loans and leases receivable. Excludes loans and leases covered under loss sharing agreements.

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Amount of deferred interest and fee income, unamortized costs incurred to originate loans and leases, unamortized loan commitments and loan syndication fees, and premiums over or discounts from face amounts of acquired loans. Excludes amounts for loans and leases covered under loss sharing agreements.

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