Note 3 - Available for Sale Debt Securities - Available-for-sale Securities by Contractual Maturity (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Due within 1 year, amortized cost	$ 76,966
Due within 1 year, fair value	77,108
Due after 1 but within 5 years, amortized cost	31,054
Due after 1 but within 5 years, fair value	31,618
Due after 5 but within 10 years, amortized cost	5,482
Due after 5 but within 10 years, fair value	5,583
Due after 10 years, amortized cost	103,133
Due after 10 years, fair value	104,932
Mortgage-backed securities – government agencies, amortized cost	219,811
Mortgage-backed securities – government agencies, fair value	226,572
Total securities available-for-sale, amortized cost	436,446	$ 469,313
Total securities available-for-sale, fair value	$ 445,813	$ 470,738

Amortized cost of 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 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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+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=121645371&loc=d3e27198-111563

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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
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 210
-Section S99
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
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-URI http://asc.fasb.org/extlink&oid=121558606&loc=SL82898722-210454

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
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-Section 45
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