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Note 7 - Investment and Equity Securities - Amortized Cost and Fair Values of Securities Available for Sale (Details) - USD ($) $ in Thousands	Sep. 30, 2019	Dec. 31, 2018
Amortized cost	$ 102,418	$ 98,516
Gross unrealized gains	2,742	855
Gross unrealized losses	(119)	(1,049)
Investment securities available for sale, at fair value	105,041	98,322
US Government Agencies Debt Securities [Member]
Amortized cost	2,000	7,442
Gross unrealized gains		90
Gross unrealized losses	(1)	(61)
Investment securities available for sale, at fair value	1,999	7,471
Subordinated Debt Securities [Member]
Amortized cost	4,000
Gross unrealized gains	150
Gross unrealized losses
Investment securities available for sale, at fair value	4,150
Taxable Municipal Bonds [Member]
Amortized cost	500	502
Gross unrealized gains	3	10
Gross unrealized losses
Investment securities available for sale, at fair value	503	512
Nontaxable Municipal Bonds [Member]
Amortized cost	76,816	72,387
Gross unrealized gains	2,322	667
Gross unrealized losses		(473)
Investment securities available for sale, at fair value	79,138	72,581
Mortgage-backed Securities, Issued by US Government Sponsored Enterprises [Member]
Amortized cost	19,102	18,185
Gross unrealized gains	267	88
Gross unrealized losses	(118)	(515)
Investment securities available for sale, at fair value	$ 19,251	$ 17,758

X

- Definition

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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