Note 3 - Available-for-sale Securities - Investment Securities (Details) - USD ($) $ in Thousands	Jun. 30, 2019	Dec. 31, 2018
Available-for-sale securities, amortized cost	$ 44,606	$ 40,610
Available-for-sale securities, gross unrealized gains	333	108
Available-for-sale securities, gross unrealized losses	(1,100)	(1,222)
Available-for-sale securities	43,839	39,496
Mortgage-backed Securities, Issued by US Government Sponsored Enterprises [Member]
Available-for-sale securities, amortized cost	19,211	20,626
Available-for-sale securities, gross unrealized gains	110	43
Available-for-sale securities, gross unrealized losses	(72)	(196)
Available-for-sale securities	19,249	20,473
Corporate Debt Securities [Member]
Available-for-sale securities, amortized cost	17,000	14,000
Available-for-sale securities, gross unrealized gains	93
Available-for-sale securities, gross unrealized losses	(1,028)	(1,026)
Available-for-sale securities	16,065	12,974
Subordinated Notes [Member]
Available-for-sale securities, amortized cost	6,903	4,500
Available-for-sale securities, gross unrealized gains	126	64
Available-for-sale securities, gross unrealized losses
Available-for-sale securities	7,029	4,564
US Treasury Securities [Member]
Available-for-sale securities, amortized cost	1,492	1,484
Available-for-sale securities, gross unrealized gains	4	1
Available-for-sale securities, gross unrealized losses
Available-for-sale securities	$ 1,496	$ 1,485

Amount, before tax, of unrealized gain in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Amount, before tax, of unrealized loss in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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