Note 4 - Fair Value Measurements - Securities By Contractual Maturity (Details) $ in Thousands	Mar. 31, 2019 USD ($)
Available-for-sale, 5-10 years, amortized cost	$ 27,922
Available-for-sale, 5-10 years, fair value	27,262
Held-to-maturity, 5-10 years, amortized cost	13,633
Held-to-maturity, 5-10 years, fair value	13,122
Available-for-sale, 10+ years, amortized cost	26,651
Available-for-sale, 10+ years, fair value	26,256
Held-to-maturity, 10+ years, amortized cost
Held-to-maturity, 10+ years, fair value
Available-for-sale, total, amortized cost	54,573
Available-for-sale, total, fair value	53,518
Held-to-maturity, total, amortized cost	13,633
Held-to-maturity, total, fair value	$ 13,122

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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