Note 3 - Securities - Fair Value of Securities (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Amortized cost	$ 41,732	$ 59,884
Gross unrealized gains	318	322
Gross unrealized losses	(2)	(13)
Fair value	42,048	60,193
Certificates of Deposit [Member]
Amortized cost	32,724	48,666
Gross unrealized gains	0	0
Gross unrealized losses	0	0
Fair value	32,724	48,666
US States and Political Subdivisions Debt Securities [Member]
Amortized cost	503	505
Gross unrealized gains	9	8
Gross unrealized losses	0	0
Fair value	512	513
Residential Mortgage Backed Securities [Member]
Amortized cost	6,124	7,727
Gross unrealized gains	305	310
Gross unrealized losses	0	0
Fair value	6,429	8,037
Collateralized Mortgage Backed Securities [Member]
Amortized cost	2,381	2,986
Gross unrealized gains	4	4
Gross unrealized losses	(2)	(13)
Fair value	$ 2,383	$ 2,977

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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