Note 4 - Investment Securities - Schedule of Investment Securities (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Available for sale, at amortized cost	$ 190,803	$ 197,960
Available for sale, gross unrealized gains	696	1,369
Available for sale, gross unrealized losses	(3,023)	(744)
Available for sale securities, at fair value	188,476	198,585
Held to maturity, at amortized cost	26,977	0
Held to maturity, gross unrealized gains	16
Held to maturity, gross unrealized losses	(1,903)
Held to maturity securities, fair value	25,090	0
US Treasury and Government [Member]
Available for sale, at amortized cost	5,657	49,612
Available for sale, gross unrealized gains	5	5
Available for sale, gross unrealized losses	(31)	(117)
Available for sale securities, at fair value	5,631	49,500
US States and Political Subdivisions Debt Securities [Member]
Available for sale, at amortized cost	88,276	63,276
Available for sale, gross unrealized gains	343	717
Available for sale, gross unrealized losses	(1,569)	(60)
Available for sale securities, at fair value	87,050	63,933
Held to maturity, at amortized cost	26,977
Held to maturity, gross unrealized gains	16
Held to maturity, gross unrealized losses	(1,903)
Held to maturity securities, fair value	25,090
Collateralized Mortgage Backed Securities [Member]
Available for sale, at amortized cost	96,870	85,072
Available for sale, gross unrealized gains	348	647
Available for sale, gross unrealized losses	(1,423)	(567)
Available for sale securities, at fair value	$ 95,795	$ 85,152

Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

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