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Note 3 - Loans and Allowance for Loan Losses - Concentrations Within the Loan Portfolio (Details) - USD ($)	Dec. 31, 2022	Dec. 31, 2021
Financing Receivable, before Allowance for Credit Loss, Total	$ 3,916,619,000	$ 3,453,459,000
Percent of portfolio	100.00%	100.00%
Commercial Real Estate Loans to Lessors of Non Residential Buildings [Member]
Financing Receivable, before Allowance for Credit Loss, Total	$ 738,891,000	$ 737,589,000
Percent of portfolio	18.90%	21.40%

X

- Definition

Loan portfolio classes and segments expressed as a percentage of the companies aggregate loans.

+ References

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- Definition

Amortized cost, before allowance for credit loss, of financing receivable. Excludes financing receivable covered under loss sharing agreement and net investment in lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
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