Note 7 - Investment and Equity Securities - Amortized Cost and Fair Values of Securities Available for Sale (Details) - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017
Amortized cost	$ 91,732	$ 93,631
Gross unrealized gains	979	2,048
Gross unrealized losses	(1,449)	(396)
Investment securities available for sale, at fair value	91,262	95,283
US Government Agencies Debt Securities [Member]
Amortized cost	8,342	8,664
Gross unrealized gains	70	126
Gross unrealized losses	(107)	(71)
Investment securities available for sale, at fair value	8,305	8,719
Taxable Municipal Bonds [Member]
Amortized cost	504	504
Gross unrealized gains	14	8
Gross unrealized losses
Investment securities available for sale, at fair value	518	512
Nontaxable Municipal Bonds [Member]
Amortized cost	64,986	65,408
Gross unrealized gains	829	1,547
Gross unrealized losses	(754)	(38)
Investment securities available for sale, at fair value	65,061	66,917
Mortgage-backed Securities, Issued by US Government Sponsored Enterprises [Member]
Amortized cost	17,900	18,640
Gross unrealized gains	66	157
Gross unrealized losses	(588)	(287)
Investment securities available for sale, at fair value	$ 17,378	18,510
Debt Securities [Member]
Amortized cost		93,216
Gross unrealized gains		1,838
Gross unrealized losses		(396)
Investment securities available for sale, at fair value		94,658
Equity Securities [Member]
Amortized cost		415
Gross unrealized gains		210
Gross unrealized losses
Investment securities available for sale, at fair value		$ 625

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

No definition available.

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- Definition

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

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27161-111563

+ Details

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- Definition

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

+ References

No definition available.

+ Details

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- Definition

This item represents the cost of debt and equity securities, which are categorized neither as held-to-maturity nor trading, net of adjustments including accretion, amortization, collection of cash, previous other-than-temporary impairments recognized in earnings (less any cumulative-effect adjustments recognized, as defined), and fair value hedge accounting adjustments, if any.

+ References

No definition available.

+ Details

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