Regulatory Matters (Regulatory capital amounts and ratios) (Details) - Security Federal Bank [Member]	Dec. 31, 2021
Tier 1 Leverage (Core) Capital (To Adjusted Tangible Assets)
For Capital Adequacy, Ratio	0.040
To Be Well Capitalized Under Prompt Corrective Action Provisions, Ratio	0.050
Tier 1 Risk-Based Core Capital (To Risk Weighted Assets)
For Capital Adequacy, Ratio	0.060
To Be Well Capitalized Under Prompt Corrective Action Provisions, Ratio	0.080
Total Risk-Based Capital (To Risk Weighted Assets)
For Capital Adequacy, Ratio	0.080
To Be Well Capitalized Under Prompt Corrective Action Provisions, Ratio	0.100
For Capital Adequacy, Ratio	0.060
To Be Well Capitalized Under Prompt Corrective Action Provisions, Ratio	0.080
For Capital Adequacy, Ratio	0.080
To Be Well Capitalized Under Prompt Corrective Action Provisions, Ratio	0.100
For Capital Adequacy, Ratio	0.040
To Be Well Capitalized Under Prompt Corrective Action Provisions, Ratio	0.050

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Ratio of minimum total risk-based capital to risk-weighted assets required for capital adequacy as defined by regulatory framework.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 505
-Section 50
-Paragraph 1B
-URI https://asc.fasb.org/extlink&oid=117337116&loc=SL5958570-112826

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
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-Section 50
-Paragraph 1
-Subparagraph (c)(1)
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Ratio of minimum total risk-based capital to risk-weighted assets categorized as well capitalized as defined by regulatory framework for prompt corrective action.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 505
-Section 50
-Paragraph 1
-Subparagraph (c)(1)
-URI https://asc.fasb.org/extlink&oid=117337116&loc=SL5958568-112826

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Ratio of minimum Tier 1 leverage capital to average assets required for capital adequacy as defined by regulatory framework.

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Ratio of minimum Tier 1 leverage capital to average assets categorized as well capitalized as defined by regulatory framework for prompt corrective action.

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Ratio of minimum Tier 1 risk-based capital to risk-weighted assets required for capital adequacy as defined by regulatory framework.

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Ratio of minimum Tier 1 risk-based capital to risk-weighted assets categorized as well capitalized as defined by regulatory framework for prompt corrective action.

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