Note 9 - Long-term Borrowings (Details Textual) - USD ($)	Jun. 30, 2020	Dec. 31, 2019
Federal Home Loan Bank, Advances, General Debt Obligations, Disclosures, Collateral Pledged	$ 873,986,000
Long-term Federal Home Loan Bank Advances, Total	0	$ 0
Public Deposit Accounts	267,663,000
US States and Political Subdivisions Debt Securities [Member]
Deposit Liabilities, Collateral Issued, Financial Instruments	$ 73,293,000
FHLB Line of Credit [Member]
Debt Instrument, Percentage of Assets	30.00%
Letters of Credit Outstanding, Amount	$ 205,000,000

The percentage of assets equal to the debt instrument.

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- Definition

Amount of funds accepted from public in form of deposit.

+ References

No definition available.

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- Definition

Amount of securities, mortgage loans, or other financial instruments pledged as collateral for deposits.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 405
-Section 50
-Paragraph 1
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- Definition

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

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 470
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-Paragraph 3
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- Definition

Including both current and noncurrent portions, Federal Home Loan Bank borrowings initially due beyond one year or beyond the normal operating cycle if longer.

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The total amount of the contingent obligation under letters of credit outstanding as of the reporting date.

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