Note 6 - Securities (Details Textual)	3 Months Ended	12 Months Ended
Mar. 31, 2020 USD ($)	Mar. 31, 2019 USD ($)	Dec. 31, 2019 USD ($)
Equity Securities, FV-NI	$ 994,000		$ 979,000
Mutual Fund [Member]
Available-for-sale, Securities in Unrealized Loss Positions, Qualitative Disclosure, Number of Positions, Total	1		1
Equity Securities Unrealized Loss Cumulative Amount	$ 6,000		$ 21,000
Equity Securities, FV-NI, Unrealized Gain (Loss), Total	(15,000)	$ (12,000)
Federal Home Loan Bank of Pittsburgh [Member] \| FHLB Stock [Member]
Other than Temporary Impairment Losses, Investments, Total	0		0
Other Assets [Member] \| Federal Home Loan Bank of Pittsburgh [Member]
Federal Home Loan Bank Stock	9,206,000		10,131,000
Investment Securities [Member]
Debt Securities, Available-for-sale, Restricted	$ 206,718,000		$ 215,270,000

The cumulative amount of unrealized loss from equity securities.

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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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Amount of restricted 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
-Name Accounting Standards Codification
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Amount of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

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-Name Accounting Standards Codification
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Amount of unrealized gain (loss) on investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

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Federal Home Loan Bank (FHLB) stock represents an equity interest in a FHLB. It does not have a readily determinable fair value because its ownership is restricted and it lacks a market (liquidity).

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The amount by which the fair value of an investment 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.

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