Note 3 - Investment Securities - Amortized Cost and Fair Value of Investment Securities by Contractual Maturity (Details) - USD ($) $ in Thousands	Sep. 30, 2019	Dec. 31, 2018
Due In One Year or Less, amortized cost	$ 149
Due In One Year or Less, fair value	149
Due After One Year Through Five Years, amortized cost	4,338
Due After One Year Through Five Years, fair value	4,351
Due After Five Years Through Ten Years, amortized cost	924
Due After Five Years Through Ten Years, fair value	956
Due After Ten Years, amortized cost	1,079
Due After Ten Years, fair value	1,102
Amortized cost with single maturity date	6,490
Fair value with single maturity date	6,558
Mortgage-Backed Securities, amortized cost	360,406
Mortgage-Backed Securities, fair value	362,311
Amortized cost	366,896	$ 363,433
Fair Value	$ 368,869	$ 353,066

Amortized cost of 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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