Note 5 - Investment Securities (Details Textual) - USD ($)		12 Months Ended
Apr. 30, 2018	Dec. 31, 2018	Dec. 31, 2017
Other than Temporary Impairment, Credit Losses Recognized in Earnings, Credit Losses on Debt Securities Held, Ending Balance		$ 0
Debt Securities, Available-for-sale, Realized Gain		0	$ 207,000
Debt Securities, Available-for-sale, Realized Loss		0	8,000
Increase (Decrease) in Income Taxes			(22,000)
First West Virginia Bancorp [Member]
Proceeds from Sale of Debt Securities, Available-for-sale	$ 80,300,000
Collateral Pledged [Member]
Debt Securities, Available-for-sale, Restricted		$ 126,100,000	$ 83,800,000

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).

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 9
-Subparagraph (a)
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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).

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Amount of restricted 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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The cumulative amount of credit losses recognized in earnings related to debt securities held for which a portion of an other than temporary impairment (OTTI) was recognized in other comprehensive income (a component of shareholders' equity).

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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).

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