Note 2 - Investment Securities - Investment Securities (Details) - USD ($) $ in Thousands	Jun. 30, 2020	Dec. 31, 2019
Securities available for sale, amortized cost	$ 249,231	$ 251,819
Securities available for sale, gross unrealized gains	7,950	3,644
Securities available for sale, gross unrealized losses	82	901
Securities available for sale, fair value	257,099	254,562
Mortgage-backed Securities, Issued by US Government Sponsored Enterprises [Member]
Securities available for sale, amortized cost	68,289	69,984
Securities available for sale, gross unrealized gains	1,587	90
Securities available for sale, gross unrealized losses	0	576
Securities available for sale, fair value	69,876	69,498
Agency Collateralized Mortgage Obligations [Member]
Securities available for sale, amortized cost	34,903	43,067
Securities available for sale, gross unrealized gains	368	238
Securities available for sale, gross unrealized losses	80	221
Securities available for sale, fair value	35,191	43,084
US Government Agencies Debt Securities [Member]
Securities available for sale, amortized cost	56,833	64,162
Securities available for sale, gross unrealized gains	1,414	473
Securities available for sale, gross unrealized losses	0	79
Securities available for sale, fair value	58,247	64,556
Municipal Notes [Member]
Securities available for sale, amortized cost	89,206	74,606
Securities available for sale, gross unrealized gains	4,581	2,843
Securities available for sale, gross unrealized losses	2	25
Securities available for sale, fair value	$ 93,785	$ 77,424

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).

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
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Amortized cost 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
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=121645371&loc=d3e27161-111563

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 30
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=121558606&loc=SL82898722-210454

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-Publisher FASB
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-Topic 320
-SubTopic 10
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