Note 7 - Securities Available for Sale - Summary of Securities Available for Sale (Details) - USD ($) $ in Thousands	Sep. 30, 2017	Dec. 31, 2016
Amortized cost	$ 79,120	$ 79,839
Gross unrealized gains	111	92
Gross unrealized losses	(880)	(1,454)
Fair value	78,351	78,477
Mortgage-backed Securities, Issued by US Government Sponsored Enterprises [Member] \| Federal Home Loan Mortgage Corporation Certificates and Obligations (FHLMC) [Member]
Amortized cost	141	327
Gross unrealized gains	4	10
Gross unrealized losses	0	0
Fair value	145	337
Mortgage-backed Securities, Issued by US Government Sponsored Enterprises [Member] \| Federal National Mortgage Association Certificates and Obligations (FNMA) [Member]
Amortized cost	5,086	295
Gross unrealized gains	2	7
Gross unrealized losses	(22)	0
Fair value	5,066	302
Collateralized Mortgage Obligations [Member] \| Federal National Mortgage Association Certificates and Obligations (FNMA) [Member]
Amortized cost	238	371
Gross unrealized gains	1	0
Gross unrealized losses	0	(5)
Fair value	239	366
Collateralized Mortgage Backed Securities [Member]
Amortized cost	5,465	993
Gross unrealized gains	7	17
Gross unrealized losses	(22)	(5)
Fair value	5,450	1,005
Other Marketable Securities [Member]
Amortized cost	73,655	78,846
Gross unrealized gains	104	75
Gross unrealized losses	(858)	(1,449)
Fair value	72,901	77,472
Other Marketable Securities [Member] \| US Government Agencies Debt Securities [Member]
Amortized cost	69,960	74,979
Gross unrealized gains	0	16
Gross unrealized losses	(681)	(1,079)
Fair value	69,279	73,916
Other Marketable Securities [Member] \| US States and Political Subdivisions Debt Securities [Member]
Amortized cost	2,703	2,819
Gross unrealized gains	14	0
Gross unrealized losses	(2)	(20)
Fair value	2,715	2,799
Other Marketable Securities [Member] \| Corporate Debt Securities [Member]
Amortized cost	234	290
Gross unrealized gains	2	2
Gross unrealized losses	0	0
Fair value	236	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	88	57
Gross unrealized losses	0	0
Fair value	$ 146	$ 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
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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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