Note 3 - Investment Securities: Schedule of amortized cost and estimated fair values of debt securities (Details) - USD ($)	Mar. 31, 2019	Dec. 31, 2018
US States and Political Subdivisions Debt Securities
Available-for-sale Securities, Amortized Cost Basis	$ 211,069,360	$ 212,613,724
Debt Securities, Available-for-sale, Maturity, without Single Maturity Date, Fair Value	217,735,663	211,888,274
Held to Maturity, at amortized cost	381,695	787,987
Debt Securities, Held-to-maturity, Fair Value	93,645	793,283
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	371,140	311,442
Available-for-sale Securities, Amortized Cost Basis	211,199,676	212,744,040
Debt Securities, Available-for-sale, Maturity, without Single Maturity Date, Fair Value	218,106,803	212,199,716
Held to Maturity, at amortized cost	$ 381,695	$ 787,987

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=118939692&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=118939692&loc=d3e27232-111563

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