Note 3 - Investment Securities - Amortized Cost and Fair Value (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Amortized cost	$ 32,771	$ 32,817
Unrealized gains	767	229
Unrealized losses	(31)	(165)
Fair value	33,507	32,881
Collateralized Mortgage Backed Securities [Member]
Amortized cost	15,212	19,540
Unrealized gains	472	61
Unrealized losses		(97)
Fair value	15,684	19,504
Corporate Debt Securities [Member]
Amortized cost	1,500	1,500
Unrealized gains
Unrealized losses		(67)
Fair value	1,500	1,433
US States and Political Subdivisions Debt Securities [Member]
Amortized cost	16,059	11,777
Unrealized gains	295	168
Unrealized losses	(31)	(1)
Fair value	$ 16,323	$ 11,944

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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