Note 3 - Investment Securities (Details Textual) - USD ($)	6 Months Ended
Jun. 30, 2019	Jun. 30, 2018	Dec. 31, 2018
Proceeds from Sale of Debt Securities, Available-for-sale	$ 56,821,000	$ 11,268,000
Debt Securities, Available-for-sale, Realized Gain	117,000	116,000
Debt Securities, Available-for-sale, Realized Loss	52,000	0
Proceeds from Sale of Held-to-maturity Securities	1,766,000	0
Debt Securities, Held-to-maturity, Sold, Realized Gain (Loss)	0	$ 0
Security Owned and Pledged as Collateral, Fair Value, Total	$ 169,821,000		$ 178,978,000
Available-for-sale, Securities in Unrealized Loss Positions, Qualitative Disclosure, Number of Positions, Total	103
Depreciated Debt Securities With Unrealized Losses	1.60%
Other than Temporary Impairment Losses, Investments, Available-for-sale Securities, Total	$ 0

Refers to the depreciated percentage of debt securities with unrealized losses measuring in amortized cost basis.

No definition available.

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- Definition

Number of investment positions in available-for-sale investments in a continuous unrealized loss position for which an other-than-temporary impairment (OTTI) has not been recognized in the income statement.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 6
-Subparagraph (b)(3)
-URI http://asc.fasb.org/extlink&oid=118939692&loc=d3e27290-111563

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- Definition

Amount of realized gain on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
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-Subparagraph (a)
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- Definition

Amount of realized loss on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

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Amount of gain (loss) on sale of investment in debt security measured at amortized cost (held-to-maturity), including other-than-temporary impairment (OTTI).

+ References

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-Paragraph 10
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The amount by which the fair value of an investment in debt and equity securities categorized as Available-for-sale is less than the amortized cost basis or carrying amount of that investment at the balance sheet date and the decline in fair value is deemed to be other than temporary, before considering whether or not such amount is recognized in earnings or other comprehensive income.

+ References

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- Definition

Amount of cash inflow from sale of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

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-Publisher FASB
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The cash inflow associated with the sale of securities that had been designated as held-to-maturity. Excludes proceeds from maturities, prepayments and calls by the issuer.

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- Definition

Fair value of financial instrument held by the entity for its own account (proprietary securities) for trading or investment purposes that are carried at fair value and pledged to counterparties as collateral for financing transactions.

+ References

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-SubTopic 30
-Section 50
-Paragraph 1A
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