Refers to number of securities included in investment portfolio.

No definition available.

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- Definition

Amount of accumulated unrealized loss on investments in debt securities classified as held-to-maturity and available-for-sale in a continuous loss position.

+ References

No definition available.

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- Definition

This item represents the fair value of securities categorized as held-to-maturity and available-for-sale which are in an unrealized loss position.

+ References

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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- 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

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- Definition

Amount of realized gain (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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- 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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- Definition

Amount of tax expense (benefit) of reclassification adjustment from accumulated other comprehensive income for unrealized gain (loss) realized upon the sale of available-for-sale securities.

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This item represents an increase to the cumulative amount of credit losses recognized in earnings for an other than temporary impairment (OTTI) of a debt security held for which a previous OTTI was recognized and the investor does not intend to sell the debt security and it is not more likely than not that the investor will be required to sell the debt security before recovery of its amortized cost basis.

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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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Note 5 - Investment Securities (Details Textual)	3 Months Ended		9 Months Ended		12 Months Ended
Note 5 - Investment Securities (Details Textual)	Sep. 30, 2020 USD ($)	Sep. 30, 2019 USD ($)	Sep. 30, 2020 USD ($)	Sep. 30, 2019 USD ($)	Dec. 31, 2019 USD ($)
Other than Temporary Impairment, Credit Losses Recognized in Earnings, Additions, Additional Credit Losses			$ 0		$ 0
Securities, Continuous Loss Position, Accumulated Loss	$ 4,100,000		4,100,000		5,900,000
Securities, Continuous Unrealized Loss Position, Fair Value	169,600,000		169,600,000		$ 353,200,000
Proceeds from Sale of Debt Securities, Available-for-sale	32,400,000	$ 11,500,000	125,222,000	$ 54,742,000
Debt Securities, Available-for-sale, Realized Gain (Loss), Total	279,000	520,000	2,800,000	1,100,000
Other Comprehensive Income (Loss), Reclassification Adjustment from AOCI for Sale of Securities, Tax, Total	$ 71,000	$ 132,000	$ 700,000	280,000
Debt Securities, Available-for-sale, Realized Gain				1,200,000
Debt Securities, Available-for-sale, Realized Loss				$ 67,000
Mortgage-backed Securities, Issued by Private Enterprises [Member]
Number of Securities in Investment Portfolio	0		0		0
Mortgage-backed Securities, Issued by Private Enterprises [Member] \| Subprime [Member]
Number of Securities in Investment Portfolio	0		0		0
Mortgage-backed Securities, Issued by Private Enterprises [Member] \| AltA [Member]
Number of Securities in Investment Portfolio	0		0		0
US Government Agencies Debt Securities [Member]
Available-for-sale, Securities in Unrealized Loss Positions, Qualitative Disclosure, Number of Positions, Total	4		4
Collateralized Mortgage Obligations [Member]
Number of Securities in Investment Portfolio	0		0		0
Available-for-sale, Securities in Unrealized Loss Positions, Qualitative Disclosure, Number of Positions, Total	14		14
Agency Mortgage-backed Securities [Member]
Available-for-sale, Securities in Unrealized Loss Positions, Qualitative Disclosure, Number of Positions, Total	2		2
Corporate Debt Securities [Member]
Available-for-sale, Securities in Unrealized Loss Positions, Qualitative Disclosure, Number of Positions, Total	7		7