Note 3 - Available-for-sale Securities - Investment Securities (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Available-for-sale securities, amortized cost	$ 47,181	$ 48,860
Available-for-sale securities, gross unrealized gains	431	405
Available-for-sale securities, gross unrealized losses	(2,782)	(948)
Available-for-sale securities	44,830	48,317
Mortgage-backed Securities, Issued by US Government Sponsored Enterprises [Member]
Available-for-sale securities, amortized cost	15,334	16,663
Available-for-sale securities, gross unrealized gains	305	90
Available-for-sale securities, gross unrealized losses	(21)	(68)
Available-for-sale securities	15,618	16,685
Corporate Debt Securities [Member]
Available-for-sale securities, amortized cost	18,017	18,018
Available-for-sale securities, gross unrealized gains		133
Available-for-sale securities, gross unrealized losses	(2,522)	(838)
Available-for-sale securities	15,495	17,313
Subordinated Notes [Member]
Available-for-sale securities, amortized cost	9,025	9,022
Available-for-sale securities, gross unrealized gains	126	182
Available-for-sale securities, gross unrealized losses	(204)
Available-for-sale securities	8,947	9,204
SBA Loan Pools [Member]
Available-for-sale securities, amortized cost	4,805	5,157
Available-for-sale securities, gross unrealized gains
Available-for-sale securities, gross unrealized losses	(35)
Available-for-sale securities	$ 4,770	5,115
US Treasury Securities [Member]
Available-for-sale securities, amortized cost		5,157
Available-for-sale securities, gross unrealized gains
Available-for-sale securities, gross unrealized losses		(42)
Available-for-sale securities		$ 5,115

Amount, before tax, of unrealized gain in accumulated other comprehensive income (AOCI) 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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Amount, before tax, of unrealized loss in accumulated other comprehensive income (AOCI) 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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