Note 7 - Deposits - Certificates of Deposit with Balances of $100,000 or More (Details) - USD ($)	Dec. 31, 2021	Dec. 31, 2020
Up to three months	$ 68,887,000	$ 79,500,000
Three months to six months	53,077,000	79,373,000
Six months to twelve months	56,612,000	77,363,000
Over twelve months	120,545,000	153,331,000
Total certificates of deposit	$ 299,121,000	$ 389,567,000

- Definition

Amount of time deposit liabilities, including certificates of deposit, in denominations of $100,000 or more, maturing after twelve months from the balance sheet date.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher SEC
-Name Industry Guide
-Number 3
-Section V
-Paragraph D-E

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- Definition

Amount of time deposit liabilities, including certificates of deposit, in denominations of $100,000 or more, maturing within six to twelve months after the balance sheet date.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher SEC
-Name Industry Guide
-Number 3
-Section V
-Paragraph D-E

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- Definition

Amount of time deposit liabilities, including certificates of deposit, in denominations of $100,000 or more, maturing within three months or fewer from the balance sheet date.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher SEC
-Name Industry Guide
-Number 3
-Section V
-Paragraph D-E

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- Definition

Amount of time deposit liabilities, including certificates of deposit, in denominations of $100,000 or more, maturing within three to six months after the balance sheet date.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher SEC
-Name Industry Guide
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-Paragraph D-E

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- Definition

Amount of time deposit liabilities, including certificates of deposit, in denominations of $100,000 or more.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher SEC
-Name Industry Guide
-Number 3
-Section V
-Paragraph D-E

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