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Note 2 - Securities - Available-for-sale Securities (Details) - USD ($)	Jun. 30, 2020	Dec. 31, 2019
Securities available for sale, amortized cost	$ 299,958,000	$ 329,979,000
Securities available for sale, gross unrealized gains	7,739,000	5,930,000
Securities available for sale, gross unrealized losses	(36,000)	(1,254,000)
Securities available for sale, fair value	307,661,000	334,655,000
US Government Agencies Debt Securities [Member]
Securities available for sale, amortized cost	161,575,000	185,103,000
Securities available for sale, gross unrealized gains	957,000	2,449,000
Securities available for sale, gross unrealized losses	(35,000)	(1,142,000)
Securities available for sale, fair value	162,497,000	186,410,000
Collateralized Mortgage Backed Securities [Member]
Securities available for sale, amortized cost	34,765,000	41,998,000
Securities available for sale, gross unrealized gains	1,269,000	554,000
Securities available for sale, gross unrealized losses	(1,000)	(82,000)
Securities available for sale, fair value	36,033,000	42,470,000
Municipal General Obligation Bonds [Member]
Securities available for sale, amortized cost	97,171,000	98,245,000
Securities available for sale, gross unrealized gains	5,296,000	2,864,000
Securities available for sale, gross unrealized losses	0	(30,000)
Securities available for sale, fair value	102,467,000	101,079,000
Municipal Revenue Bonds [Member]
Securities available for sale, amortized cost	5,947,000	4,133,000
Securities available for sale, gross unrealized gains	217,000	63,000
Securities available for sale, gross unrealized losses	0	0
Securities available for sale, fair value	6,164,000	4,196,000
Other Debt and Equity Securities [Member]
Securities available for sale, amortized cost	500,000	500,000
Securities available for sale, gross unrealized gains	0	0
Securities available for sale, gross unrealized losses	0	0
Securities available for sale, fair value	$ 500,000	$ 500,000

X

- Definition

Amount, before tax, of unrealized gain in accumulated other comprehensive income (AOCI) 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, before tax, of unrealized loss in accumulated other comprehensive income (AOCI) 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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+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
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-Topic 320
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-Section 45
-Paragraph 1
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Amount of 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
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-Name Accounting Standards Codification
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