Note 4 - Securities - Securities Reconciliation (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Securities available-for-sale securities, at amortized costs	$ 176,518	$ 157,432
Securities available-for-sale securities, gross unrealized gains	1,164	2,346
Securities available-for-sale securities, gross unrealized losses	(2,508)	(748)
Securities available-for-sale, at fair value	175,174	159,030
Securities held-to-maturity, at amortized cost	31,187	35,899
Securities held-to-maturity	31,374
US States and Political Subdivisions Debt Securities [Member]
Securities available-for-sale securities, at amortized costs	58,847	59,332
Securities available-for-sale securities, gross unrealized gains	1,001	1,811
Securities available-for-sale securities, gross unrealized losses	(420)	(39)
Securities available-for-sale, at fair value	59,428	61,104
Securities held-to-maturity, at amortized cost	31,187	35,899
Securities held-to-maturity securities, gross unrealized gains	710	966
Securities held-to-maturity securities, gross unrealized losses	(523)	(220)
Securities held-to-maturity	31,374	36,645
US Government Agencies Debt Securities [Member]
Securities available-for-sale securities, at amortized costs		3,886
Securities available-for-sale securities, gross unrealized gains		57
Securities available-for-sale securities, gross unrealized losses
Securities available-for-sale, at fair value		3,943
Residential Mortgage Backed Securities and Collateralized Mortgage Obligations [Member]
Securities available-for-sale securities, at amortized costs	71,068	32,215
Securities available-for-sale securities, gross unrealized gains	33	192
Securities available-for-sale securities, gross unrealized losses	(1,497)	(270)
Securities available-for-sale, at fair value	69,604	32,137
Corporate Debt Securities [Member]
Securities available-for-sale securities, at amortized costs	16,153	33,775
Securities available-for-sale securities, gross unrealized gains	103	194
Securities available-for-sale securities, gross unrealized losses	(140)	(191)
Securities available-for-sale, at fair value	16,116	33,778
Commercial Mortgage Backed Securities [Member]
Securities available-for-sale securities, at amortized costs	15,786	12,893
Securities available-for-sale securities, gross unrealized gains	9	10
Securities available-for-sale securities, gross unrealized losses	(281)	(134)
Securities available-for-sale, at fair value	15,514	12,769
Asset-backed Securities [Member]
Securities available-for-sale securities, at amortized costs	14,664	15,331
Securities available-for-sale securities, gross unrealized gains	18	82
Securities available-for-sale securities, gross unrealized losses	(170)	(114)
Securities available-for-sale, at fair value	$ 14,512	$ 15,299

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

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