11) Retirement Plans: Deferred Compensation Plans (Details) - Employee Stock Ownership Plan - USD ($)	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019
Pretax contributions	$ 19,500	$ 19,000
Contribution to plan	1,690,568	695,560
Compensation expenses	900,000	660,000
Present value of anticipated benefits	6,656,363	5,722,837
Payment to retirement compensation	133,843	133,843
Deferred Compensation Arrangement with Individual, Recorded Liability	$ 669,212	$ 803,055
Common Class A
Shares reserved for future issuance	231,312
Common Class C
Shares reserved for future issuance	118,880

No definition available.

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- Definition

Represents the monetary amount of Present value of anticipated benefits, during the indicated time period.

+ References

No definition available.

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- Definition

Aggregate number of common shares reserved for future issuance.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.29)
-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

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- Definition

The carrying amount of the liability as of the balance sheet date to an individual under a deferred compensation arrangement. This amount may be the result of periodic accruals made over the period of active employment, or reflect termination benefits resulting contractual terms or a death benefit.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 710
-SubTopic 10
-Section 30
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6409875&loc=d3e20015-108363

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- Definition

This item represents the amount of cash contributions during the period made by the entity to the Employee Stock Ownership Plan (ESOP).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 40
-Section 50
-Paragraph 1
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=109244661&loc=d3e17540-113929

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- Definition

The amount of plan compensation cost recognized during the period.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 40
-Section 50
-Paragraph 1
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-URI http://asc.fasb.org/extlink&oid=109244661&loc=d3e17540-113929

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