Note 3 - Securities - Securities Available-for-sale With Unrealized Losses (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Less than 12 Months - Fair Value		$ 15,041
Less than 12 Months - Unrealized Loss		(84)
12 Months or More - Fair Value	198	23,343
12 Months or More - Unrealized Loss	(2)	(218)
Fair Value	198	38,384
Unrealized Loss	(2)	(302)
Mortgage-backed Securities, Issued by Private Enterprises [Member]
Less than 12 Months - Fair Value		15,041
Less than 12 Months - Unrealized Loss		(84)
12 Months or More - Fair Value	198	21,344
12 Months or More - Unrealized Loss	(2)	(212)
Fair Value	198	36,385
Unrealized Loss	$ (2)	(296)
US Government-sponsored Enterprises Debt Securities [Member]
Less than 12 Months - Fair Value
Less than 12 Months - Unrealized Loss
12 Months or More - Fair Value		1,999
12 Months or More - Unrealized Loss		(6)
Fair Value		1,999
Unrealized Loss		$ (6)

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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