Note 3 - Investment Securities: Schedule of amortized cost and estimated fair values of debt securities (Details) - USD ($)	Mar. 31, 2020	Dec. 31, 2019
US States and Political Subdivisions Debt Securities
Available-for-sale Securities, Amortized Cost Basis	$ 196,209,243	$ 192,240,250
Debt Securities, Available-for-sale, Maturity, without Single Maturity Date, Fair Value	208,800,652	204,012,197
Held to Maturity, at amortized cost	380,177	380,561
Debt Securities, Held-to-maturity, Fair Value	386,726	389,520
Corporate Debt Securities
Available-for-sale Securities, Amortized Cost Basis	130,316	130,316
Debt Securities, Available-for-sale, Maturity, without Single Maturity Date, Fair Value	275,228	445,325
Available-for-sale Securities, Amortized Cost Basis	196,339,559	192,370,566
Debt Securities, Available-for-sale, Maturity, without Single Maturity Date, Fair Value	209,075,880	204,457,522
Held to Maturity, at amortized cost	$ 380,177	$ 380,561

This item represents the cost of debt and equity securities, which are categorized neither as held-to-maturity nor trading, net of adjustments including accretion, amortization, collection of cash, previous other-than-temporary impairments recognized in earnings (less any cumulative-effect adjustments recognized, as defined), and fair value hedge accounting adjustments, if any.

No definition available.

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- Definition

Fair value of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), without single maturity date and not allocated over maturity grouping.

+ 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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- Definition

Amount, before other-than-temporary impairment (OTTI) accretion, of investment in debt securities measured at amortized cost (held-to-maturity).

+ References

No definition available.

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- Definition

Fair value of investment in debt security measured at amortized cost (held-to-maturity).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 5
-Subparagraph (aa)
-URI http://asc.fasb.org/extlink&oid=121645371&loc=d3e27232-111563

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(6))
-URI http://asc.fasb.org/extlink&oid=120398452&loc=d3e534808-122878

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 5A
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=121645371&loc=SL120269820-111563

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