Note 3 - Investment Securities - Amortized Cost and Fair Value of Securities by Contractual Maturity (Details) - USD ($) $ in Thousands	Jun. 30, 2021	Dec. 31, 2020
Available for sale securities, due in one year or less, amortized cost	$ 4,706
Available for sale securities, due in one year or less, fair value	4,743
Available for sale securities, due from one to five years, amortized cost	13,736
Available for sale securities, due from one to five years, fair value	14,263
Available for sale securities, due from five to ten years, amortized cost	48,293
Available for sale securities, due from five to ten years, fair value	49,090
Available for sale securities, due after ten years, amortized cost	98,418
Available for sale securities, due after ten years, fair value	103,009
Total available for sale securities debt maturities, amortized cost	165,153
Total available for sale securities, debt maturities, fair value	171,105
Securities available-for-sale, amortized cost	227,291	$ 155,005
Securities available-for-sale	233,992	162,946
Collateralized Mortgage Backed Securities [Member]
Available for sale securities, without single maturity, amortized cost	14,029
Available for sale securities, without single maturity, fair value	14,118
Securities available-for-sale, amortized cost	14,029	7,513
Securities available-for-sale	14,118	7,669
Collateralized Mortgage Obligations [Member]
Available for sale securities, without single maturity, amortized cost	48,109
Available for sale securities, without single maturity, fair value	48,769
Securities available-for-sale, amortized cost	48,109	30,339
Securities available-for-sale	$ 48,769	$ 31,189

Amortized cost of 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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