Note 3 - Investment Securities - Amortized Cost and Fair Value of Securities by Contractual Maturity (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Available for sale securities, due in one year or less, amortized cost	$ 9,116
Available for sale securities, due in one year or less, fair value	9,134
Available for sale securities, due from one to five years, amortized cost	10,005
Available for sale securities, due from one to five years, fair value	10,085
Available for sale securities, due from five to ten years, amortized cost	8,738
Available for sale securities, due from five to ten years, fair value	9,078
Available for sale securities, due after ten years, amortized cost	54,624
Available for sale securities, due after ten years, fair value	55,749
Total available for sale securities debt maturities, amortized cost	82,483
Total available for sale securities, debt maturities, fair value	84,046
Securities available-for-sale, amortized cost	125,072	$ 143,982
Securities available-for-sale	126,875	142,165
Collateralized Mortgage Backed Securities [Member]
Available for sale securities, without single maturity, amortized cost	9,460
Available for sale securities, without single maturity, fair value	9,495
Securities available-for-sale, amortized cost	9,460	19,635
Securities available-for-sale	9,495	19,348
Collateralized Mortgage Obligations [Member]
Available for sale securities, without single maturity, amortized cost	33,129
Available for sale securities, without single maturity, fair value	33,334
Securities available-for-sale, amortized cost	33,129	24,229
Securities available-for-sale	$ 33,334	$ 23,875

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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