Note 2 - Investment Securities - Available-for-sale Securities (Details) - USD ($) $ in Thousands	Mar. 31, 2017	Dec. 31, 2016
Securities available-for-sale, amortized cost	$ 52,180	$ 53,060
Securities available-for-sale, gross unrealized gains	517	504
Securities available-for-sale, gross unrealized losses	(538)	(589)
Securities available-for-sale	52,159	52,975
US Government Agencies Debt Securities [Member]
Securities available-for-sale, amortized cost	11,814	12,422
Securities available-for-sale, gross unrealized gains	107	118
Securities available-for-sale, gross unrealized losses	(71)	(96)
Securities available-for-sale	11,850	12,444
Mortgage-backed Securities, Issued by US Government Sponsored Enterprises [Member]
Securities available-for-sale, amortized cost	21,523	19,979
Securities available-for-sale, gross unrealized gains	55	54
Securities available-for-sale, gross unrealized losses	(261)	(265)
Securities available-for-sale	21,317	19,768
Corporate Debt Securities [Member]
Securities available-for-sale, amortized cost	5,000	5,000
Securities available-for-sale, gross unrealized gains	118	66
Securities available-for-sale, gross unrealized losses
Securities available-for-sale	5,118	5,066
US States and Political Subdivisions Debt Securities [Member]
Securities available-for-sale, amortized cost	13,843	15,659
Securities available-for-sale, gross unrealized gains	237	266
Securities available-for-sale, gross unrealized losses	(206)	(228)
Securities available-for-sale	$ 13,874	$ 15,697

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

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
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Reference 2: http://www.xbrl.org/2003/role/presentationRef
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Amount before tax of unrealized gain in accumulated other comprehensive income (AOCI) on investments in debt and equity securities classified as available-for-sale.

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Amount before tax of unrealized loss in accumulated other comprehensive income (AOCI) on investments in debt and equity securities classified as available-for-sale.

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