Note 7 - Securities Available for Sale - Summary of Securities Available for Sale (Details) - USD ($) $ in Thousands	Jun. 30, 2017	Dec. 31, 2016
Amortized cost	$ 79,410	$ 79,839
Gross unrealized gains	101	92
Gross unrealized losses	(864)	(1,454)
Fair value	78,647	78,477
Mortgage-backed Securities, Issued by US Government Sponsored Enterprises [Member] \| Federal Home Loan Mortgage Corporation Certificates and Obligations (FHLMC) [Member]
Amortized cost	188	327
Gross unrealized gains	6	10
Gross unrealized losses	0	0
Fair value	194	337
Mortgage-backed Securities, Issued by US Government Sponsored Enterprises [Member] \| Federal National Mortgage Association Certificates and Obligations (FNMA) [Member]
Amortized cost	149	295
Gross unrealized gains	3	7
Gross unrealized losses	0	0
Fair value	152	302
Collateralized Mortgage Obligations [Member] \| Federal Home Loan Mortgage Corporation Certificates and Obligations (FHLMC) [Member]
Amortized cost		371
Gross unrealized gains		0
Gross unrealized losses		(5)
Fair value		366
Collateralized Mortgage Obligations [Member] \| Federal National Mortgage Association Certificates and Obligations (FNMA) [Member]
Amortized cost	266
Gross unrealized gains	2
Gross unrealized losses	(1)
Fair value	267
Collateralized Mortgage Backed Securities [Member]
Amortized cost	603	993
Gross unrealized gains	11	17
Gross unrealized losses	(1)	(5)
Fair value	613	1,005
Other Marketable Securities [Member]
Amortized cost	78,807	78,846
Gross unrealized gains	90	75
Gross unrealized losses	(863)	(1,449)
Fair value	78,034	77,472
Other Marketable Securities [Member] \| US Government Agencies Debt Securities [Member]
Amortized cost	74,978	74,979
Gross unrealized gains	4	16
Gross unrealized losses	(686)	(1,079)
Fair value	74,296	73,916
Other Marketable Securities [Member] \| US States and Political Subdivisions Debt Securities [Member]
Amortized cost	2,809	2,819
Gross unrealized gains	11	0
Gross unrealized losses	(2)	(20)
Fair value	2,818	2,799
Other Marketable Securities [Member] \| Corporate Debt Securities [Member]
Amortized cost	262	290
Gross unrealized gains	3	2
Gross unrealized losses	0	0
Fair value	265	292
Other Marketable Securities [Member] \| Preferred Stock [Member]
Amortized cost	700	700
Gross unrealized gains	0	0
Gross unrealized losses	(175)	(350)
Fair value	525	350
Other Marketable Securities [Member] \| Equity Securities [Member]
Amortized cost	58	58
Gross unrealized gains	72	57
Gross unrealized losses	0	0
Fair value	$ 130	$ 115

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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