Note 3 - Investment Securities - Investment Securities (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Securities available for sale, amortized cost	$ 266,437	$ 273,878
Securities available for sale, gross unrealized gains	862	1,275
Securities available for sale, gross unrealized losses	5,458	3,981
Securities available for sale	261,841	271,172
Securities-held to maturity		1
Securities held to maturity, gross unrealized gains
Securities held to maturity, gross unrealized losses
Securities held to maturity		1
Mortgage-backed Securities, Issued by US Government Sponsored Enterprises [Member]
Securities available for sale, amortized cost	94,746	114,902
Securities available for sale, gross unrealized gains
Securities available for sale, gross unrealized losses	3,489	2,253
Securities available for sale	91,257	112,649
Securities-held to maturity		1
Securities held to maturity, gross unrealized gains
Securities held to maturity, gross unrealized losses
Securities held to maturity		1
Agency Collateralized Mortgage Obligations [Member]
Securities available for sale, amortized cost	33,222	15,660
Securities available for sale, gross unrealized gains	152	1
Securities available for sale, gross unrealized losses	382	338
Securities available for sale	32,992	15,323
US Government Agencies Debt Securities [Member]
Securities available for sale, amortized cost	75,461	70,013
Securities available for sale, gross unrealized gains	59
Securities available for sale, gross unrealized losses	1,016	985
Securities available for sale	74,504	69,028
Municipal Notes [Member]
Securities available for sale, amortized cost	63,008	73,303
Securities available for sale, gross unrealized gains	651	1,274
Securities available for sale, gross unrealized losses	571	405
Securities available for sale	$ 63,088	$ 74,172

Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

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Amount before tax of unrealized gain in accumulated other comprehensive income (AOCI) on investments in debt and equity securities classified as available-for-sale.

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-Publisher FASB
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Amount before tax of unrealized loss in accumulated other comprehensive income (AOCI) on investments in debt and equity securities classified as available-for-sale.

+ References

No definition available.

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This item represents the cost of debt and equity securities, which are categorized neither as held-to-maturity nor trading, net of adjustments including accretion, amortization, collection of cash, previous other-than-temporary impairments recognized in earnings (less any cumulative-effect adjustments recognized, as defined), and fair value hedge accounting adjustments, if any.

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Amount of investment in debt security measured at amortized cost (held-to-maturity).

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
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Amount of accumulated unrecognized gain on investment in debt security measured at amortized cost (held-to-maturity).

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Amount of accumulated unrealized loss on investment in debt security measured at amortized cost (held-to-maturity).

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Fair value of investment in debt security measured at amortized cost (held-to-maturity).

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