Note 3 - Available-for-sale Securities - Investment Securities (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Available-for-sale securities, amortized cost	$ 48,860	$ 40,610
Available-for-sale securities, gross unrealized gains	405	108
Available-for-sale securities, gross unrealized losses	(948)	(1,222)
Available-for-sale securities	48,317	39,496
Mortgage-backed Securities, Issued by US Government Sponsored Enterprises [Member]
Available-for-sale securities, amortized cost	16,663	20,626
Available-for-sale securities, gross unrealized gains	90	43
Available-for-sale securities, gross unrealized losses	(68)	(196)
Available-for-sale securities	16,685	20,473
Corporate Debt Securities [Member]
Available-for-sale securities, amortized cost	18,018	14,000
Available-for-sale securities, gross unrealized gains	133
Available-for-sale securities, gross unrealized losses	(838)	(1,026)
Available-for-sale securities	17,313	12,974
Subordinated Notes [Member]
Available-for-sale securities, amortized cost	9,022	4,500
Available-for-sale securities, gross unrealized gains	182	64
Available-for-sale securities, gross unrealized losses
Available-for-sale securities	9,204	4,564
SBA Loan Pools [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
US Treasury Securities [Member]
Available-for-sale securities, amortized cost		1,484
Available-for-sale securities, gross unrealized gains		1
Available-for-sale securities, gross unrealized losses
Available-for-sale securities		$ 1,485

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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