3. INVESTMENT SECURITIES: Available-for-sale Securities (Details) - USD ($)	Dec. 31, 2020	Dec. 31, 2019
Available-for-sale Securities, Amortized Cost Basis	$ 204,330,167	$ 192,370,566
Available-for-sale Securities, Gross Unrealized Gain	16,725,273	12,111,048
Available-for-sale Securities, Gross Unrealized Loss	(1,022)	(24,092)
Available-for-sale Securities, Estimated Fair Value	221,054,418	204,457,522
US States and Political Subdivisions Debt Securities
Available-for-sale Securities, Amortized Cost Basis	204,199,851	192,240,250
Available-for-sale Securities, Gross Unrealized Gain	16,464,476	11,796,039
Available-for-sale Securities, Gross Unrealized Loss	(1,022)	(24,092)
Available-for-sale Securities, Estimated Fair Value	220,663,305	204,012,197
Corporate Debt Securities
Available-for-sale Securities, Amortized Cost Basis	130,316	130,316
Available-for-sale Securities, Gross Unrealized Gain	260,797	315,009
Available-for-sale Securities, Gross Unrealized Loss	0	0
Available-for-sale Securities, Estimated Fair Value	$ 391,113	$ 445,325

Represents the monetary amount of Available-for-sale Securities, Estimated Fair Value, as of the indicated date.

No definition available.

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- Definition

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.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Amount of unrealized gain before deducting unrealized loss on investments in debt and equity securities classified as available-for-sale securities.

+ References

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

+ Details

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- Definition

Amount of unrealized loss before deducting unrealized gain on investments in available-for-sale securities.

+ References

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

+ Details

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