Note 3 - Securities - Securities Available-for-sale With Unrealized Losses (Details) - USD ($) $ in Thousands	Sep. 30, 2017	Dec. 31, 2016
Less than 12 Months - Fair Value	$ 53,395	$ 74,587
Less than 12 Months - Unrealized Loss	(379)	(1,996)
12 Months or More - Fair Value	12,823
12 Months or More - Unrealized Loss	(291)
Fair Value	66,218	74,587
Unrealized Loss	(670)	(1,996)
US Government-sponsored Enterprises Debt Securities [Member]
Less than 12 Months - Fair Value	10,987	10,544
Less than 12 Months - Unrealized Loss	(24)	(80)
12 Months or More - Fair Value	2,592
12 Months or More - Unrealized Loss	(24)
Fair Value	13,579	10,544
Unrealized Loss	(48)	(80)
Mortgage-backed Securities, Issued by Private Enterprises [Member]
Less than 12 Months - Fair Value	42,408	64,043
Less than 12 Months - Unrealized Loss	(355)	(1,916)
12 Months or More - Fair Value	10,231
12 Months or More - Unrealized Loss	(267)
Fair Value	52,639	64,043
Unrealized Loss	$ (622)	$ (1,916)

Amount of accumulated unrealized loss on investments in debt and equity securities classified as available-for-sale that have been in a continuous loss position for twelve months or longer.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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