Note 4 - Available for Sale Securities - Amortized Cost and Fair Value (Details) - USD ($) $ in Thousands	Jun. 30, 2018	Dec. 31, 2017
Amortized cost	$ 56,480	$ 58,392
Gross unrealized gains	69	164
Gross unrealized losses	(1,414)	(544)
Estimated fair value	55,135	58,012
US Government Corporations and Agencies Securities [Member]
Amortized cost	1,875	2,211
Gross unrealized gains	3	11
Gross unrealized losses	(7)	(2)
Estimated fair value	1,871	2,220
US States and Political Subdivisions Debt Securities [Member]
Amortized cost	9,894	13,102
Gross unrealized gains	40	104
Gross unrealized losses	(149)	(69)
Estimated fair value	9,785	13,137
Collateralized Mortgage Backed Securities [Member]
Amortized cost	35,626	33,908
Gross unrealized gains	17	14
Gross unrealized losses	(1,079)	(455)
Estimated fair value	34,564	33,467
Certificates of Deposit [Member]
Amortized cost	4,000	4,000
Gross unrealized gains	1	6
Gross unrealized losses	(103)	(9)
Estimated fair value	3,898	3,997
Corporate Debt Securities [Member]
Amortized cost	5,085	5,171
Gross unrealized gains	8	29
Gross unrealized losses	(76)	(9)
Estimated fair value	$ 5,017	$ 5,191

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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