Note 7 - Investment and Equity Securities - Amortized Cost and Fair Values of Securities Available for Sale (Details) - USD ($) $ in Thousands	Jun. 30, 2020	Dec. 31, 2019
Amortized cost	$ 107,768	$ 103,401
Gross unrealized gains	4,761	2,466
Gross unrealized losses	0	(134)
Investment securities available for sale, at fair value	112,529	105,733
Subordinated Debt Securities [Member]
Amortized cost	11,050	4,000
Gross unrealized gains	239	126
Gross unrealized losses	0	0
Investment securities available for sale, at fair value	11,289	4,126
Taxable Municipal Bonds [Member]
Amortized cost	500	500
Gross unrealized gains	2	1
Gross unrealized losses	0	0
Investment securities available for sale, at fair value	502	501
Nontaxable Municipal Bonds [Member]
Amortized cost	80,155	80,436
Gross unrealized gains	3,883	2,065
Gross unrealized losses	0	(25)
Investment securities available for sale, at fair value	84,038	82,476
Mortgage-backed Securities, Issued by US Government Sponsored Enterprises [Member]
Amortized cost	16,063	18,465
Gross unrealized gains	637	274
Gross unrealized losses	0	(109)
Investment securities available for sale, at fair value	$ 16,700	$ 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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