Note 4 - Securities - Available-for-sale Debt Securities by Contractual Maturity (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
One year or less, amortized cost	$ 2,195
One year or less, fair value	2,201
After one year through five years, amortized cost	49,724
After one year through five years, fair value	50,936
After five years through ten years, amortized cost	51,056
After five years through ten years, fair value	52,525
After ten years, amortized cost	20,147
After ten years, fair value	19,979
Total, amortized cost	268,971	$ 301,779
Available-for-sale debt securities	272,839	296,032
Asset-backed Securities [Member]
Securities without a single maturity, amortized cost	5,618
Securities without a single maturity, fair value	5,621
Total, amortized cost	5,618	1,825
Available-for-sale debt securities	5,621	1,802
Collateralized Mortgage Obligations [Member]
Securities without a single maturity, amortized cost	122,089
Securities without a single maturity, fair value	123,092
Collateralized Mortgage Backed Securities [Member]
Securities without a single maturity, amortized cost	18,142
Securities without a single maturity, fair value	18,485
Total, amortized cost	18,142	24,165
Available-for-sale debt securities	$ 18,485	$ 23,934

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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