Regulatory Matters (Regulatory capital amounts and ratios) (Details) - Security Federal Bank [Member]	Dec. 31, 2018
Tier 1 Risk-Based Core Capital (To Risk Weighted Assets)
For Capital Adequacy, Ratio	6.00%
To Be Well Capitalized Under Prompt Corrective Action Provisions, Ratio	8.00%
Total Risk-Based Capital (To Risk Weighted Assets)
For Capital Adequacy, Ratio	8.00%
To Be Well Capitalized Under Prompt Corrective Action Provisions, Ratio	10.00%
Tier 1 Leverage (Core) Capital (To Adjusted Tangible Assets)
For Capital Adequacy, Ratio	4.00%
To Be Well Capitalized Under Prompt Corrective Action Provisions, Ratio	5.00%

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The minimum Total risk based capital ratio (total capital divided by risk weighted assets) required for capital adequacy purposes under the regulatory framework for prompt corrective action.

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The Total risk based capital ratio (total capital divided by risk weighted assets) required to be categorized as "well capitalized", in the regulatory framework for prompt corrective action.

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The minimum amount of Tier 1 Leverage Capital for capital adequacy purposes divided by average assets as defined in the regulations.

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The amount of Tier 1 Leverage Capital required to be categorized as well capitalized divided by average assets as defined in the regulatory framework for prompt corrective action.

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The minimum Tier One Capital Ratio (Tier one capital divided by risk-weighted assets) required for capital adequacy purposes under the regulatory framework for prompt corrective action.

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-Publisher FASB
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