Note 7 - Investment and Equity Securities - Amortized Cost and Fair Values of Securities Available for Sale (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Amortized cost	$ 105,790	$ 103,401
Gross unrealized gains	1,007	2,466
Gross unrealized losses	(3,838)	(134)
Investment securities available for sale, at fair value	102,959	105,733
Subordinated Debt Securities [Member]
Amortized cost	4,000	4,000
Gross unrealized gains	221	126
Gross unrealized losses
Investment securities available for sale, at fair value	4,221	4,126
Taxable Municipal Bonds [Member]
Amortized cost	500	500
Gross unrealized gains	1	1
Gross unrealized losses
Investment securities available for sale, at fair value	501	501
Nontaxable Municipal Bonds [Member]
Amortized cost	84,343	80,436
Gross unrealized gains	236	2,065
Gross unrealized losses	(3,824)	(25)
Investment securities available for sale, at fair value	80,755	82,476
Mortgage-backed Securities, Issued by US Government Sponsored Enterprises [Member]
Amortized cost	16,947	18,465
Gross unrealized gains	549	274
Gross unrealized losses	(14)	(109)
Investment securities available for sale, at fair value	$ 17,482	$ 18,630

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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