Regulatory Matters (Regulatory capital amounts and ratios) (Details) - USD ($)	Sep. 30, 2016	Dec. 31, 2015
Tier 1 Risk-Based Core Capital (To Risk Weighted Assets)
Actual, Amount	$ 90,047	$ 84,671,763
Actual, Ratio	21.20%	21.70%
For Capital Adequacy, Amount	$ 25,475	$ 23,429,060
For Capital Adequacy, Ratio	6.00%	6.00%
Total Risk-Based Capital (To Risk Weighted Assets)
Actual, Amount	$ 99,874	$ 95,428,763
Actual, Ratio	23.50%	24.40%
For Capital Adequacy, Amount	$ 33,967	$ 31,238,746
For Capital Adequacy, Ratio	8.00%	8.00%
Common Equity Tier One Capital	$ 67,536
Tier 1 Leverage (Core) Capital (To Adjusted Tangible Assets)
Actual, Amount	$ 90,047	$ 84,672,000
Actual, Ratio	11.10%	10.60%
For Capital Adequacy, Amount	$ 32,338	$ 31,810,743
For Capital Adequacy, Ratio	4.00%	4.00%
Security Federal Bank [Member]
Tier 1 Risk-Based Core Capital (To Risk Weighted Assets)
Actual, Amount	$ 88,588,000	$ 87,728,000
Actual, Ratio	20.90%	22.50%
For Capital Adequacy, Amount	$ 25,456,920	$ 23,440,440
For Capital Adequacy, Ratio	6.00%	6.00%
To Be Well Capitalized Under Prompt Corrective Action Provisions, Amount	$ 33,943	$ 31,253,920
To Be Well Capitalized Under Prompt Corrective Action Provisions, Ratio	8.00%	8.00%
Total Risk-Based Capital (To Risk Weighted Assets)
Actual, Amount	$ 93,926,000	$ 92,653,000
Actual, Ratio	22.10%	23.70%
For Capital Adequacy, Amount	$ 33,942,560	$ 31,253,920
For Capital Adequacy, Ratio	8.00%	8.00%
To Be Well Capitalized Under Prompt Corrective Action Provisions, Amount	$ 42,428	$ 39,067,400
To Be Well Capitalized Under Prompt Corrective Action Provisions, Ratio	10.00%	10.00%
Common Equity Tier One Capital	$ 88,588,000
Tier 1 Leverage (Core) Capital (To Adjusted Tangible Assets)
Actual, Amount	$ 88,588,000	$ 87,728,000
Actual, Ratio	11.00%	11.00%
For Capital Adequacy, Amount	$ 32,329,120	$ 31,800,960
For Capital Adequacy, Ratio	4.00%	4.00%
To Be Well Capitalized Under Prompt Corrective Action Provisions, Amount	$ 40,411	$ 39,751,200
To Be Well Capitalized Under Prompt Corrective Action Provisions, Ratio	5.00%	5.00%