Note 8 - Investment Securities (Details Textual) $ in Thousands	3 Months Ended
Mar. 31, 2022 USD ($)	Mar. 31, 2021 USD ($)	Dec. 31, 2021 USD ($)
Interest Receivable	$ 60,056		$ 56,994
Equity Securities, FV-NI, Unrealized Gain (Loss), Total	5,874	$ (2,752)
Equity Securities, FV-NI, Current	$ 27,740		$ 22,319
Debt Securities, Available-for-Sale, Unrealized Loss Position, Number of Positions	156		88
Debt Securities, Available-for-Sale, Allowance for Credit Loss, Ending Balance	$ 0	$ 0
Pledged Investment Securities	$ 28,800		$ 30,500
Mortgage-Backed Securities, Issued by US Government Sponsored Enterprises [Member]
Debt Securities, Available-for-Sale, Unrealized Loss Position, Number of Positions	135		70
Corporate Debt Securities [Member]
Debt Securities, Available-for-Sale, Unrealized Loss Position, Number of Positions	14		12
Debt Securities, Available-for-sale [Member]
Interest Receivable	$ 2,900

Pledged investment securities at carrying value.

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Amount of allowance for credit loss on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Number of investments in debt securities measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in unrealized loss position, without allowance for credit loss. Includes beneficial interest in securitized financial asset.

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Amount of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI), classified as current.

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Amount of unrealized gain (loss) on investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

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Carrying amount as of the balance sheet date of interest earned but not received. Also called accrued interest or accrued interest receivable.

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