Note 3 - Securities - Securities Available-for-sale With Unrealized Losses (Details) - USD ($) $ in Thousands	Sep. 30, 2019	Dec. 31, 2018
Less than 12 Months - Fair Value	$ 24,046	$ 10,545
Less than 12 Months - Unrealized Loss	(89)	(44)
12 Months or More - Fair Value	24,523	71,298
12 Months or More - Unrealized Loss	(286)	(2,759)
Fair Value	48,569	81,843
Unrealized Loss	(375)	(2,803)
US Government-sponsored Enterprises Debt Securities [Member]
Less than 12 Months - Fair Value		1,981
Less than 12 Months - Unrealized Loss		(1)
12 Months or More - Fair Value	1,995	8,679
12 Months or More - Unrealized Loss	(12)	(214)
Fair Value	1,995	10,660
Unrealized Loss	(12)	(215)
Mortgage-backed Securities, Issued by Private Enterprises [Member]
Less than 12 Months - Fair Value	24,046	8,564
Less than 12 Months - Unrealized Loss	(89)	(43)
12 Months or More - Fair Value	22,528	62,619
12 Months or More - Unrealized Loss	(274)	(2,545)
Fair Value	46,574	71,183
Unrealized Loss	$ (363)	$ (2,588)

Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in continuous unrealized loss position for more than 12 months, without allowance for credit loss. Includes beneficial interest in securitized financial asset.

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