$SFDL
SECURITY FEDERAL CORP Stock $sfdl

$sfdl Overview Financials Valuation SEC Filings Company Website

2020 Q4 Form 10-K Financial Statement

#000093905721000114 Filed on March 29, 2021

Income Statement

Concept	2020 Q4	2020 Q3	2020 Q2
Revenue	$9.564M	$9.339M	$9.098M
YoY Change	4.71%	-3.13%	-0.33%
Cost Of Revenue
YoY Change
Gross Profit
YoY Change
Gross Profit Margin
Selling, General & Admin
YoY Change
% of Gross Profit
Research & Development
YoY Change
% of Gross Profit
Depreciation & Amortization	$490.0K	$689.1K	$746.6K
YoY Change	16.67%	6.87%	16.69%
% of Gross Profit
Operating Expenses
YoY Change
Operating Profit
YoY Change
Interest Expense	$1.175M	$1.431M	$1.756M
YoY Change	-47.47%	-37.54%	-12.59%
% of Operating Profit
Other Income/Expense, Net		$513.7K	$558.9K
YoY Change		-51.23%	-68.96%
Pretax Income	$3.832M	$1.010M	$2.457M
YoY Change	112.77%	-62.51%	3.67%
Income Tax	$767.0K	$105.0K	$441.0K
% Of Pretax Income	20.02%	10.4%	17.95%
Net Earnings	$3.065M	$3.179M	$2.016M
YoY Change	91.32%	198.71%	7.01%
Net Earnings / Revenue	32.05%	34.04%	22.16%
Basic Earnings Per Share	$0.94	$0.28	$0.62
Diluted Earnings Per Share	$0.94	$0.28	$0.62
COMMON SHARES
Basic Shares Outstanding	3.253M shares	3.253M shares	3.253M shares
Diluted Shares Outstanding	3.253M shares	3.253M shares	3.253M shares

Balance Sheet

Concept	2020 Q4	2020 Q3	2020 Q2
SHORT-TERM ASSETS
Cash & Short-Term Investments
YoY Change
Cash & Equivalents	$18.03M	$15.61M	$15.34M
Short-Term Investments
Other Short-Term Assets
YoY Change
Inventory
Prepaid Expenses
Receivables
Other Receivables
Total Short-Term Assets
YoY Change
LONG-TERM ASSETS
Property, Plant & Equipment	$26.58M	$26.70M	$27.05M
YoY Change	-2.37%	1.22%	6.06%
Goodwill	$1.200M	$1.200M	$1.200M
YoY Change	0.0%	0.0%	0.0%
Intangibles
YoY Change
Long-Term Investments
YoY Change
Other Assets
YoY Change
Total Long-Term Assets
YoY Change
TOTAL ASSETS
Total Short-Term Assets
Total Long-Term Assets
Total Assets	$1.172B	$1.129B	$1.101B
YoY Change	21.64%	13.92%	13.06%
SHORT-TERM LIABILITIES
YoY Change
Accounts Payable
YoY Change
Accrued Expenses	$2.400M	$2.500M	$2.600M
YoY Change	-11.11%	-10.71%	-10.34%
Deferred Revenue
YoY Change
Short-Term Debt	$61.80M	$35.80M	$30.70M
YoY Change	432.76%	138.67%	94.3%
Long-Term Debt Due
YoY Change
Total Short-Term Liabilities	$2.400M	$2.500M	$2.600M
YoY Change	-11.11%	-10.71%	-10.34%
LONG-TERM LIABILITIES
Long-Term Debt	$35.20M	$35.20M	$35.20M
YoY Change	-14.56%	214.29%	214.29%
Other Long-Term Liabilities	$7.100M	$6.400M	$6.900M
YoY Change	14.52%	-7.25%	2.99%
Total Long-Term Liabilities	$42.30M	$41.60M	$42.10M
YoY Change	-10.76%	129.83%	135.2%
TOTAL LIABILITIES
Total Short-Term Liabilities	$2.400M	$2.500M	$2.600M
Total Long-Term Liabilities	$42.30M	$41.60M	$42.10M
Total Liabilities	$1.060B	$1.020B	$993.4M
YoY Change	21.61%	13.48%	12.35%
SHAREHOLDERS EQUITY
Retained Earnings	$85.03M	$82.29M	$81.71M
YoY Change	7.25%	5.53%	7.44%
Common Stock
YoY Change
Preferred Stock
YoY Change
Treasury Stock (at cost)	$4.331M	$4.331M	$4.331M
YoY Change	0.0%	0.0%	0.0%
Treasury Stock Shares	200.9K shares	200.9K shares	200.9K shares
Shareholders Equity	$111.9M	$109.3M	$107.1M
YoY Change
Total Liabilities & Shareholders Equity	$1.172B	$1.129B	$1.101B
YoY Change	21.64%	13.92%	13.06%

Cashflow Statement

Concept	2020 Q4	2020 Q3	2020 Q2
OPERATING ACTIVITIES
Net Income	$3.065M	$3.179M	$2.016M
YoY Change	91.32%	198.71%	7.01%
Depreciation, Depletion And Amortization	$490.0K	$689.1K	$746.6K
YoY Change	16.67%	6.87%	16.69%
Cash From Operating Activities	$2.020M	$2.660M	$3.530M
YoY Change	-41.45%	-25.07%	186.99%
INVESTING ACTIVITIES
Capital Expenditures	-$360.0K	-$110.0K	-$480.0K
YoY Change	-71.43%	-91.27%	-28.36%
Acquisitions
YoY Change
Other Investing Activities	-$38.24M	-$29.20M	-$62.51M
YoY Change	-265.4%	112.52%	52.84%
Cash From Investing Activities	-$38.61M	-$29.32M	-$62.98M
YoY Change	-276.62%	95.34%	51.47%
FINANCING ACTIVITIES
Cash Dividend Paid
YoY Change
Common Stock Issuance & Retirement, Net
YoY Change
Debt Paid & Issued, Net
YoY Change
Cash From Financing Activities	39.01M	26.92M	59.33M
YoY Change	-246.87%	89.31%	83.97%
NET CHANGE
Cash From Operating Activities	2.020M	2.660M	3.530M
Cash From Investing Activities	-38.61M	-29.32M	-62.98M
Cash From Financing Activities	39.01M	26.92M	59.33M
Net Change In Cash	2.420M	260.0K	-120.0K
YoY Change	-293.6%	-90.58%	-98.52%
FREE CASH FLOW
Cash From Operating Activities	$2.020M	$2.660M	$3.530M
Capital Expenditures	-$360.0K	-$110.0K	-$480.0K
Free Cash Flow	$2.380M	$2.770M	$4.010M
YoY Change	-49.47%	-42.41%	111.05%

Facts In Submission

Frame	Concept Type	Concept / XBRL Key	Value	Unit
CY2020	dei	Entity Registrant Name EntityRegistrantName	Security Federal Corporation
CY2020	dei	Document Type DocumentType	10-K
CY2020	dei	Document Period End Date DocumentPeriodEndDate	2020-12-31
CY2020	dei	Amendment Flag AmendmentFlag	false
CY2020	dei	Entity Central Index Key EntityCentralIndexKey	0000818677
CY2020	dei	Current Fiscal Year End Date CurrentFiscalYearEndDate	--12-31
CY2021Q1	dei	Entity Common Stock Shares Outstanding EntityCommonStockSharesOutstanding	3252884	shares
CY2020Q2	dei	Entity Public Float EntityPublicFloat	44800000	USD
CY2020	dei	Entity Filer Category EntityFilerCategory	Non-accelerated Filer
CY2020	dei	Entity Current Reporting Status EntityCurrentReportingStatus	Yes
CY2020	dei	Entity Voluntary Filers EntityVoluntaryFilers	No
CY2020	dei	Entity Well Known Seasoned Issuer EntityWellKnownSeasonedIssuer	No
CY2020	dei	Document Fiscal Year Focus DocumentFiscalYearFocus	2020
CY2020	dei	Document Fiscal Period Focus DocumentFiscalPeriodFocus	FY
CY2020	dei	Entity Emerging Growth Company EntityEmergingGrowthCompany	false
CY2020	dei	Entity Small Business EntitySmallBusiness	true
CY2020	dei	Entity Shell Company EntityShellCompany	false
CY2020	dei	Document Transition Report DocumentTransitionReport	false
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CY2019	sfdl	Grant Revenue GrantRevenue	478049	USD
CY2018	sfdl	Grant Revenue GrantRevenue	343078	USD
CY2020	us-gaap	Noninterest Income Other Operating Income NoninterestIncomeOtherOperatingIncome	1081188	USD
CY2019	us-gaap	Noninterest Income Other Operating Income NoninterestIncomeOtherOperatingIncome	1137614	USD
CY2018	us-gaap	Noninterest Income Other Operating Income NoninterestIncomeOtherOperatingIncome	960792	USD
CY2020	us-gaap	Noninterest Income NoninterestIncome	11421133	USD
CY2019	us-gaap	Noninterest Income NoninterestIncome	9097143	USD
CY2018	us-gaap	Noninterest Income NoninterestIncome	7669146	USD
CY2020	us-gaap	Labor And Related Expense LaborAndRelatedExpense	17991666	USD
CY2019	us-gaap	Labor And Related Expense LaborAndRelatedExpense	16838702	USD
CY2018	us-gaap	Labor And Related Expense LaborAndRelatedExpense	15504020	USD
CY2020	us-gaap	Occupancy Net OccupancyNet	2574549	USD
CY2019	us-gaap	Occupancy Net OccupancyNet	2354347	USD
CY2018	us-gaap	Occupancy Net OccupancyNet	2228521	USD
CY2020	us-gaap	Advertising Expense AdvertisingExpense	1053658	USD
CY2019	us-gaap	Advertising Expense AdvertisingExpense	796213	USD
CY2018	us-gaap	Advertising Expense AdvertisingExpense	546799	USD
CY2018	us-gaap	Depreciation Depreciation	2307555	USD
CY2020	us-gaap	Federal Deposit Insurance Corporation Premium Expense FederalDepositInsuranceCorporationPremiumExpense	134859	USD
CY2020	us-gaap	Depreciation Depreciation	2876832	USD
CY2019	us-gaap	Depreciation Depreciation	2601104	USD
CY2019	us-gaap	Federal Deposit Insurance Corporation Premium Expense FederalDepositInsuranceCorporationPremiumExpense	84022	USD
CY2018	us-gaap	Federal Deposit Insurance Corporation Premium Expense FederalDepositInsuranceCorporationPremiumExpense	278287	USD
CY2020	us-gaap	Other Revenue Expense From Real Estate Operations OtherRevenueExpenseFromRealEstateOperations	-2033	USD
CY2019	us-gaap	Other Revenue Expense From Real Estate Operations OtherRevenueExpenseFromRealEstateOperations	65772	USD
CY2018	us-gaap	Other Revenue Expense From Real Estate Operations OtherRevenueExpenseFromRealEstateOperations	361513	USD
CY2020	us-gaap	Other Expenses OtherExpenses	5074608	USD
CY2019	us-gaap	Other Expenses OtherExpenses	5262101	USD
CY2018	us-gaap	Other Expenses OtherExpenses	5086386	USD
CY2020	us-gaap	General And Administrative Expense GeneralAndAdministrativeExpense	29708205	USD
CY2019	us-gaap	General And Administrative Expense GeneralAndAdministrativeExpense	27870717	USD
CY2018	us-gaap	General And Administrative Expense GeneralAndAdministrativeExpense	25590055	USD
CY2020	us-gaap	Income Loss From Continuing Operations Before Income Taxes Domestic IncomeLossFromContinuingOperationsBeforeIncomeTaxesDomestic	8627561	USD
CY2019	us-gaap	Income Loss From Continuing Operations Before Income Taxes Domestic IncomeLossFromContinuingOperationsBeforeIncomeTaxesDomestic	9474037	USD
CY2018	us-gaap	Income Loss From Continuing Operations Before Income Taxes Domestic IncomeLossFromContinuingOperationsBeforeIncomeTaxesDomestic	8776747	USD
CY2020	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	1576957	USD
CY2019	sfdl	Incometaxexpenseexcludingadjustment Incometaxexpenseexcludingadjustment	1679550	USD
CY2018	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	1569526	USD
CY2020	us-gaap	Net Income Loss NetIncomeLoss	7050604	USD
CY2019	us-gaap	Net Income Loss NetIncomeLoss	7794487	USD
CY2018	us-gaap	Net Income Loss NetIncomeLoss	7207221	USD
CY2020	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	2.19
CY2019	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	2.64
CY2018	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	2.44
CY2020	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	2.19
CY2019	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	2.50
CY2018	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	2.32
CY2020	us-gaap	Common Stock Dividends Per Share Cash Paid CommonStockDividendsPerShareCashPaid	0.40
CY2019	us-gaap	Common Stock Dividends Per Share Cash Paid CommonStockDividendsPerShareCashPaid	0.40
CY2018	us-gaap	Common Stock Dividends Per Share Cash Paid CommonStockDividendsPerShareCashPaid	0.36
CY2020	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	3212996	shares
CY2019	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	2955737	shares
CY2018	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	2953446	shares
CY2020	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	3212996	shares
CY2019	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	3257937	shares
CY2018	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	3256646	shares
CY2020	us-gaap	Net Income Loss NetIncomeLoss	7050604	USD
CY2019	us-gaap	Net Income Loss NetIncomeLoss	7794487	USD
CY2018	us-gaap	Net Income Loss NetIncomeLoss	7207221	USD
CY2020	us-gaap	Other Comprehensive Income Loss Available For Sale Securities Adjustment Before Reclassification Adjustments Net Of Tax OtherComprehensiveIncomeLossAvailableForSaleSecuritiesAdjustmentBeforeReclassificationAdjustmentsNetOfTax	9494218	USD
CY2019	us-gaap	Other Comprehensive Income Loss Available For Sale Securities Adjustment Before Reclassification Adjustments Net Of Tax OtherComprehensiveIncomeLossAvailableForSaleSecuritiesAdjustmentBeforeReclassificationAdjustmentsNetOfTax	5133884	USD
CY2018	us-gaap	Other Comprehensive Income Loss Available For Sale Securities Adjustment Before Reclassification Adjustments Net Of Tax OtherComprehensiveIncomeLossAvailableForSaleSecuritiesAdjustmentBeforeReclassificationAdjustmentsNetOfTax	-3065211	USD
CY2020	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci For Sale Of Securities Net Of Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesNetOfTax	999499	USD
CY2019	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci For Sale Of Securities Net Of Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesNetOfTax	614290	USD
CY2018	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci For Sale Of Securities Net Of Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesNetOfTax	429949	USD
CY2020	sfdl	Amortizationof Unrealized Gainson Afs Securities Transferredto Htm AmortizationofUnrealizedGainsonAFSSecuritiesTransferredtoHTM	-21296	USD
CY2019	sfdl	Amortizationof Unrealized Gainson Afs Securities Transferredto Htm AmortizationofUnrealizedGainsonAFSSecuritiesTransferredtoHTM	-24158	USD
CY2018	sfdl	Amortizationof Unrealized Gainson Afs Securities Transferredto Htm AmortizationofUnrealizedGainsonAFSSecuritiesTransferredtoHTM	-75962	USD
CY2020	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	8473423	USD
CY2019	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	4495436	USD
CY2018	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	-3571122	USD
CY2020	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	15524027	USD
CY2019	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	12289923	USD
CY2018	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	3636099	USD
CY2017Q4	us-gaap	Stockholders Equity StockholdersEquity	77923454	USD
CY2018	us-gaap	Net Income Loss NetIncomeLoss	7207221	USD
CY2018	us-gaap	Net Income Loss NetIncomeLoss	7207221	USD
CY2018	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	-3571122	USD
CY2018	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	-3571122	USD
CY2018	us-gaap	Dividends Common Stock Cash DividendsCommonStockCash	1063626	USD
CY2018Q4	us-gaap	Stockholders Equity StockholdersEquity	80518433	USD
CY2019	us-gaap	Net Income Loss NetIncomeLoss	7794487	USD
CY2019	us-gaap	Net Income Loss NetIncomeLoss	7794487	USD
CY2019	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	4495436	USD
CY2019	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	4495436	USD
CY2019	us-gaap	Dividends Common Stock Cash DividendsCommonStockCash	1123219	USD
CY2019Q4	us-gaap	Stockholders Equity StockholdersEquity	91758005	USD
CY2020	us-gaap	Net Income Loss NetIncomeLoss	7050604	USD
CY2020	us-gaap	Net Income Loss NetIncomeLoss	7050604	USD
CY2020	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	8473423	USD
CY2020	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	8473423	USD
CY2020	us-gaap	Dividends Common Stock Cash DividendsCommonStockCash	1301254	USD
CY2020	us-gaap	Dividends Common Stock Cash DividendsCommonStockCash	1301254	USD
CY2020Q4	us-gaap	Stockholders Equity StockholdersEquity	111905746	USD
CY2020	us-gaap	Net Income Loss NetIncomeLoss	7050604	USD
CY2019	us-gaap	Net Income Loss NetIncomeLoss	7794487	USD
CY2018	us-gaap	Net Income Loss NetIncomeLoss	7207221	USD
CY2020	us-gaap	Depreciation And Amortization DepreciationAndAmortization	1888280	USD
CY2019	us-gaap	Depreciation And Amortization DepreciationAndAmortization	1589671	USD
CY2018	us-gaap	Depreciation And Amortization DepreciationAndAmortization	1487734	USD
CY2020	us-gaap	Accretion Amortization Of Discounts And Premiums Investments AccretionAmortizationOfDiscountsAndPremiumsInvestments	-4462996	USD
CY2019	us-gaap	Accretion Amortization Of Discounts And Premiums Investments AccretionAmortizationOfDiscountsAndPremiumsInvestments	-5290316	USD
CY2018	us-gaap	Accretion Amortization Of Discounts And Premiums Investments AccretionAmortizationOfDiscountsAndPremiumsInvestments	-5705663	USD
CY2020	us-gaap	Provision For Loan Lease And Other Losses ProvisionForLoanLeaseAndOtherLosses	3600000	USD
CY2019	us-gaap	Provision For Loan Lease And Other Losses ProvisionForLoanLeaseAndOtherLosses	375000	USD
CY2018	us-gaap	Provision For Loan Lease And Other Losses ProvisionForLoanLeaseAndOtherLosses	925000	USD
CY2020	us-gaap	Life Insurance Corporate Or Bank Owned Change In Value LifeInsuranceCorporateOrBankOwnedChangeInValue	573250	USD
CY2019	us-gaap	Life Insurance Corporate Or Bank Owned Change In Value LifeInsuranceCorporateOrBankOwnedChangeInValue	540000	USD
CY2018	us-gaap	Life Insurance Corporate Or Bank Owned Change In Value LifeInsuranceCorporateOrBankOwnedChangeInValue	540000	USD
CY2020	sfdl	Bol Ideathbenefits BOLIdeathbenefits	0	USD
CY2019	sfdl	Bol Ideathbenefits BOLIdeathbenefits	138609	USD
CY2018	sfdl	Bol Ideathbenefits BOLIdeathbenefits	0	USD
CY2020	us-gaap	Loans And Leases Receivable Gain Loss On Sales Net LoansAndLeasesReceivableGainLossOnSalesNet	3508397	USD
CY2019	us-gaap	Loans And Leases Receivable Gain Loss On Sales Net LoansAndLeasesReceivableGainLossOnSalesNet	1728741	USD
CY2018	us-gaap	Loans And Leases Receivable Gain Loss On Sales Net LoansAndLeasesReceivableGainLossOnSalesNet	1250530	USD
CY2020	us-gaap	Gain Loss On Sales Of Mortgage Backed Securities Mbs GainLossOnSalesOfMortgageBackedSecuritiesMBS	625923	USD
CY2019	us-gaap	Gain Loss On Sales Of Mortgage Backed Securities Mbs GainLossOnSalesOfMortgageBackedSecuritiesMBS	-139390	USD
CY2018	us-gaap	Gain Loss On Sales Of Mortgage Backed Securities Mbs GainLossOnSalesOfMortgageBackedSecuritiesMBS	139739	USD
CY2020	us-gaap	Availableforsale Securities Gross Realized Gain Loss Excluding Other Than Temporary Impairments AvailableforsaleSecuritiesGrossRealizedGainLossExcludingOtherThanTemporaryImpairments	706743	USD
CY2019	us-gaap	Availableforsale Securities Gross Realized Gain Loss Excluding Other Than Temporary Impairments AvailableforsaleSecuritiesGrossRealizedGainLossExcludingOtherThanTemporaryImpairments	958443	USD
CY2018	us-gaap	Availableforsale Securities Gross Realized Gain Loss Excluding Other Than Temporary Impairments AvailableforsaleSecuritiesGrossRealizedGainLossExcludingOtherThanTemporaryImpairments	204185	USD
CY2020	us-gaap	Gain Loss On Sale Of Other Investments GainLossOnSaleOfOtherInvestments	0	USD
CY2019	us-gaap	Gain Loss On Sale Of Other Investments GainLossOnSaleOfOtherInvestments	0	USD
CY2018	us-gaap	Gain Loss On Sale Of Other Investments GainLossOnSaleOfOtherInvestments	229342	USD
CY2020	us-gaap	Gains Losses On Sales Of Other Real Estate GainsLossesOnSalesOfOtherRealEstate	46354	USD
CY2019	us-gaap	Gains Losses On Sales Of Other Real Estate GainsLossesOnSalesOfOtherRealEstate	184864	USD
CY2018	us-gaap	Gains Losses On Sales Of Other Real Estate GainsLossesOnSalesOfOtherRealEstate	588720	USD
CY2020	us-gaap	Real Estate Owned Valuation Allowance Amounts Applied RealEstateOwnedValuationAllowanceAmountsApplied	15000	USD
CY2019	us-gaap	Real Estate Owned Valuation Allowance Amounts Applied RealEstateOwnedValuationAllowanceAmountsApplied	22000	USD
CY2018	us-gaap	Real Estate Owned Valuation Allowance Amounts Applied RealEstateOwnedValuationAllowanceAmountsApplied	56000	USD
CY2020	us-gaap	Amortization Of Deferred Loan Origination Fees Net AmortizationOfDeferredLoanOriginationFeesNet	-1799236	USD
CY2019	us-gaap	Amortization Of Deferred Loan Origination Fees Net AmortizationOfDeferredLoanOriginationFeesNet	-202684	USD
CY2018	us-gaap	Amortization Of Deferred Loan Origination Fees Net AmortizationOfDeferredLoanOriginationFeesNet	-110036	USD
CY2020	us-gaap	Proceeds From Sale Of Loans Held For Sale ProceedsFromSaleOfLoansHeldForSale	112914762	USD
CY2019	us-gaap	Proceeds From Sale Of Loans Held For Sale ProceedsFromSaleOfLoansHeldForSale	61466054	USD
CY2018	us-gaap	Proceeds From Sale Of Loans Held For Sale ProceedsFromSaleOfLoansHeldForSale	46595060	USD
CY2020	us-gaap	Payments For Origination And Purchases Of Loans Held For Sale PaymentsForOriginationAndPurchasesOfLoansHeldForSale	111109159	USD
CY2019	us-gaap	Payments For Origination And Purchases Of Loans Held For Sale PaymentsForOriginationAndPurchasesOfLoansHeldForSale	61945934	USD
CY2018	us-gaap	Payments For Origination And Purchases Of Loans Held For Sale PaymentsForOriginationAndPurchasesOfLoansHeldForSale	44074565	USD
CY2020	us-gaap	Increase Decrease In Interest And Dividends Receivable IncreaseDecreaseInInterestAndDividendsReceivable	40197	USD
CY2019	us-gaap	Increase Decrease In Interest And Dividends Receivable IncreaseDecreaseInInterestAndDividendsReceivable	-45857	USD
CY2018	us-gaap	Increase Decrease In Interest And Dividends Receivable IncreaseDecreaseInInterestAndDividendsReceivable	190026	USD
CY2020	us-gaap	Increase Decrease In Other Receivables IncreaseDecreaseInOtherReceivables	80235	USD
CY2019	us-gaap	Increase Decrease In Other Receivables IncreaseDecreaseInOtherReceivables	-40635	USD
CY2018	us-gaap	Increase Decrease In Other Receivables IncreaseDecreaseInOtherReceivables	2849	USD
CY2020	us-gaap	Increase Decrease In Accrued Investment Income Receivable IncreaseDecreaseInAccruedInvestmentIncomeReceivable	-21420	USD
CY2019	us-gaap	Increase Decrease In Accrued Investment Income Receivable IncreaseDecreaseInAccruedInvestmentIncomeReceivable	-242347	USD
CY2018	us-gaap	Increase Decrease In Accrued Investment Income Receivable IncreaseDecreaseInAccruedInvestmentIncomeReceivable	177883	USD
CY2020	us-gaap	Increase Decrease In Customer Advances IncreaseDecreaseInCustomerAdvances	-1472	USD
CY2019	us-gaap	Increase Decrease In Customer Advances IncreaseDecreaseInCustomerAdvances	-50923	USD
CY2018	us-gaap	Increase Decrease In Customer Advances IncreaseDecreaseInCustomerAdvances	-11256	USD
CY2020	us-gaap	Operating Lease Right Of Use Asset Amortization Expense OperatingLeaseRightOfUseAssetAmortizationExpense	367015	USD
CY2019	us-gaap	Operating Lease Right Of Use Asset Amortization Expense OperatingLeaseRightOfUseAssetAmortizationExpense	371836	USD
CY2018	us-gaap	Operating Lease Right Of Use Asset Amortization Expense OperatingLeaseRightOfUseAssetAmortizationExpense	0	USD
CY2020	us-gaap	Increase Decrease In Other Operating Assets IncreaseDecreaseInOtherOperatingAssets	2470309	USD
CY2019	us-gaap	Increase Decrease In Other Operating Assets IncreaseDecreaseInOtherOperatingAssets	-233478	USD
CY2018	us-gaap	Increase Decrease In Other Operating Assets IncreaseDecreaseInOtherOperatingAssets	177273	USD
CY2020	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	12957274	USD
CY2019	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	12266241	USD
CY2018	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	14500346	USD
CY2020	us-gaap	Payments To Acquire Mortgage Backed Securities Mbs Categorized As Available For Sale PaymentsToAcquireMortgageBackedSecuritiesMBSCategorizedAsAvailableForSale	117864801	USD
CY2019	us-gaap	Payments To Acquire Mortgage Backed Securities Mbs Categorized As Available For Sale PaymentsToAcquireMortgageBackedSecuritiesMBSCategorizedAsAvailableForSale	106828636	USD
CY2018	us-gaap	Payments To Acquire Mortgage Backed Securities Mbs Categorized As Available For Sale PaymentsToAcquireMortgageBackedSecuritiesMBSCategorizedAsAvailableForSale	55486020	USD
CY2020	us-gaap	Proceeds From Maturities Prepayments And Calls Of Mortgage Backed Securities Mbs ProceedsFromMaturitiesPrepaymentsAndCallsOfMortgageBackedSecuritiesMBS	32888318	USD
CY2019	us-gaap	Proceeds From Maturities Prepayments And Calls Of Mortgage Backed Securities Mbs ProceedsFromMaturitiesPrepaymentsAndCallsOfMortgageBackedSecuritiesMBS	32283649	USD
CY2018	us-gaap	Proceeds From Maturities Prepayments And Calls Of Mortgage Backed Securities Mbs ProceedsFromMaturitiesPrepaymentsAndCallsOfMortgageBackedSecuritiesMBS	37491568	USD
CY2020	us-gaap	Proceeds From Sale Of Mortgage Backed Securities Mbs Categorized As Available For Sale ProceedsFromSaleOfMortgageBackedSecuritiesMBSCategorizedAsAvailableForSale	13884602	USD
CY2019	us-gaap	Proceeds From Sale Of Mortgage Backed Securities Mbs Categorized As Available For Sale ProceedsFromSaleOfMortgageBackedSecuritiesMBSCategorizedAsAvailableForSale	61306939	USD
CY2018	us-gaap	Proceeds From Sale Of Mortgage Backed Securities Mbs Categorized As Available For Sale ProceedsFromSaleOfMortgageBackedSecuritiesMBSCategorizedAsAvailableForSale	18081756	USD
CY2020	us-gaap	Payments To Acquire Mortgage Backed Securities Mbs Categorized As Held To Maturity PaymentsToAcquireMortgageBackedSecuritiesMBSCategorizedAsHeldToMaturity	3726280	USD
CY2019	us-gaap	Payments To Acquire Mortgage Backed Securities Mbs Categorized As Held To Maturity PaymentsToAcquireMortgageBackedSecuritiesMBSCategorizedAsHeldToMaturity	0	USD
CY2018	us-gaap	Payments To Acquire Mortgage Backed Securities Mbs Categorized As Held To Maturity PaymentsToAcquireMortgageBackedSecuritiesMBSCategorizedAsHeldToMaturity	1989922	USD
CY2020	us-gaap	Proceeds From Maturities Prepayments And Calls Of Longterm Investments ProceedsFromMaturitiesPrepaymentsAndCallsOfLongtermInvestments	4525687	USD
CY2019	us-gaap	Proceeds From Maturities Prepayments And Calls Of Longterm Investments ProceedsFromMaturitiesPrepaymentsAndCallsOfLongtermInvestments	3165575	USD
CY2018	us-gaap	Proceeds From Maturities Prepayments And Calls Of Longterm Investments ProceedsFromMaturitiesPrepaymentsAndCallsOfLongtermInvestments	3119612	USD
CY2020	us-gaap	Payments To Acquire Available For Sale Securities PaymentsToAcquireAvailableForSaleSecurities	135015731	USD
CY2019	us-gaap	Payments To Acquire Available For Sale Securities PaymentsToAcquireAvailableForSaleSecurities	83980247	USD
CY2018	us-gaap	Payments To Acquire Available For Sale Securities PaymentsToAcquireAvailableForSaleSecurities	57280900	USD
CY2020	us-gaap	Proceeds From Sale And Maturity Of Available For Sale Securities ProceedsFromSaleAndMaturityOfAvailableForSaleSecurities	28579348	USD
CY2019	us-gaap	Proceeds From Sale And Maturity Of Available For Sale Securities ProceedsFromSaleAndMaturityOfAvailableForSaleSecurities	35243895	USD
CY2018	us-gaap	Proceeds From Sale And Maturity Of Available For Sale Securities ProceedsFromSaleAndMaturityOfAvailableForSaleSecurities	31024291	USD
CY2020	us-gaap	Proceeds From Sale Of Available For Sale Securities ProceedsFromSaleOfAvailableForSaleSecurities	11148752	USD
CY2019	us-gaap	Proceeds From Sale Of Available For Sale Securities ProceedsFromSaleOfAvailableForSaleSecurities	35174873	USD
CY2018	us-gaap	Proceeds From Sale Of Available For Sale Securities ProceedsFromSaleOfAvailableForSaleSecurities	15198888	USD
CY2020	us-gaap	Proceeds From Maturities Prepayments And Calls Of Held To Maturity Securities ProceedsFromMaturitiesPrepaymentsAndCallsOfHeldToMaturitySecurities	0	USD
CY2019	us-gaap	Proceeds From Maturities Prepayments And Calls Of Held To Maturity Securities ProceedsFromMaturitiesPrepaymentsAndCallsOfHeldToMaturitySecurities	1000000	USD
CY2018	us-gaap	Proceeds From Maturities Prepayments And Calls Of Held To Maturity Securities ProceedsFromMaturitiesPrepaymentsAndCallsOfHeldToMaturitySecurities	2000000	USD
CY2020	us-gaap	Proceeds From Payments For In Interest Bearing Deposits In Banks ProceedsFromPaymentsForInInterestBearingDepositsInBanks	600000	USD
CY2019	us-gaap	Proceeds From Payments For In Interest Bearing Deposits In Banks ProceedsFromPaymentsForInInterestBearingDepositsInBanks	250005	USD
CY2018	us-gaap	Proceeds From Payments For In Interest Bearing Deposits In Banks ProceedsFromPaymentsForInInterestBearingDepositsInBanks	750000	USD
CY2020	sfdl	Purchase Of Fhlb Stock PurchaseOfFhlbStock	7239800	USD
CY2019	sfdl	Purchase Of Fhlb Stock PurchaseOfFhlbStock	11907800	USD
CY2018	sfdl	Purchase Of Fhlb Stock PurchaseOfFhlbStock	5717400	USD
CY2020	us-gaap	Payments For Proceeds From Federal Home Loan Bank Stock PaymentsForProceedsFromFederalHomeLoanBankStock	-7422300	USD
CY2019	us-gaap	Payments For Proceeds From Federal Home Loan Bank Stock PaymentsForProceedsFromFederalHomeLoanBankStock	-11575300	USD
CY2018	us-gaap	Payments For Proceeds From Federal Home Loan Bank Stock PaymentsForProceedsFromFederalHomeLoanBankStock	-6445300	USD
CY2020	us-gaap	Payments To Acquire Life Insurance Policies PaymentsToAcquireLifeInsurancePolicies	4000000	USD
CY2019	us-gaap	Payments To Acquire Life Insurance Policies PaymentsToAcquireLifeInsurancePolicies	0	USD
CY2018	us-gaap	Payments To Acquire Life Insurance Policies PaymentsToAcquireLifeInsurancePolicies	1900000	USD
CY2020	us-gaap	Proceeds From Life Insurance Policies ProceedsFromLifeInsurancePolicies	0	USD
CY2019	us-gaap	Proceeds From Life Insurance Policies ProceedsFromLifeInsurancePolicies	414855	USD
CY2018	us-gaap	Proceeds From Life Insurance Policies ProceedsFromLifeInsurancePolicies	0	USD
CY2020	us-gaap	Increase Decrease In Loans Held For Sale IncreaseDecreaseInLoansHeldForSale	30373589	USD
CY2019	us-gaap	Increase Decrease In Loans Held For Sale IncreaseDecreaseInLoansHeldForSale	22007081	USD
CY2018	us-gaap	Increase Decrease In Loans Held For Sale IncreaseDecreaseInLoansHeldForSale	42300871	USD
CY2020	us-gaap	Proceeds From Sale Of Foreclosed Assets ProceedsFromSaleOfForeclosedAssets	578994	USD
CY2019	us-gaap	Proceeds From Sale Of Foreclosed Assets ProceedsFromSaleOfForeclosedAssets	1040366	USD
CY2018	us-gaap	Proceeds From Sale Of Foreclosed Assets ProceedsFromSaleOfForeclosedAssets	1361499	USD
CY2020	us-gaap	Payments To Acquire Property Plant And Equipment PaymentsToAcquirePropertyPlantAndEquipment	1243654	USD
CY2019	us-gaap	Payments To Acquire Property Plant And Equipment PaymentsToAcquirePropertyPlantAndEquipment	4634847	USD
CY2018	us-gaap	Payments To Acquire Property Plant And Equipment PaymentsToAcquirePropertyPlantAndEquipment	2864597	USD
CY2020	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-199835854	USD
CY2019	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-47903154	USD
CY2018	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-52066796	USD
CY2020	us-gaap	Increase Decrease In Customer Deposits IncreaseDecreaseInCustomerDeposits	146688753	USD
CY2019	us-gaap	Increase Decrease In Customer Deposits IncreaseDecreaseInCustomerDeposits	3910775	USD
CY2018	us-gaap	Increase Decrease In Customer Deposits IncreaseDecreaseInCustomerDeposits	65390088	USD
CY2020	us-gaap	Proceeds From Federal Home Loan Bank Advances ProceedsFromFederalHomeLoanBankAdvances	237585000	USD
CY2019	us-gaap	Proceeds From Federal Home Loan Bank Advances ProceedsFromFederalHomeLoanBankAdvances	342223000	USD
CY2018	us-gaap	Proceeds From Federal Home Loan Bank Advances ProceedsFromFederalHomeLoanBankAdvances	204923000	USD
CY2020	us-gaap	Payments For Federal Home Loan Bank Advances PaymentsForFederalHomeLoanBankAdvances	240723000	USD
CY2019	us-gaap	Payments For Federal Home Loan Bank Advances PaymentsForFederalHomeLoanBankAdvances	338115000	USD
CY2018	us-gaap	Payments For Federal Home Loan Bank Advances PaymentsForFederalHomeLoanBankAdvances	222573000	USD
CY2020	us-gaap	Proceeds From Repayments Of Notes Payable ProceedsFromRepaymentsOfNotesPayable	0	USD
CY2019	us-gaap	Proceeds From Repayments Of Notes Payable ProceedsFromRepaymentsOfNotesPayable	-2362500	USD
CY2018	us-gaap	Proceeds From Repayments Of Notes Payable ProceedsFromRepaymentsOfNotesPayable	-6137500	USD
CY2020	us-gaap	Proceeds From Repayments Of Other Debt ProceedsFromRepaymentsOfOtherDebt	1537211	USD
CY2019	us-gaap	Proceeds From Repayments Of Other Debt ProceedsFromRepaymentsOfOtherDebt	881390	USD
CY2018	us-gaap	Proceeds From Repayments Of Other Debt ProceedsFromRepaymentsOfOtherDebt	-608732	USD
CY2020	us-gaap	Proceeds From Issuance Of Subordinated Long Term Debt ProceedsFromIssuanceOfSubordinatedLongTermDebt	0	USD
CY2019	us-gaap	Proceeds From Issuance Of Subordinated Long Term Debt ProceedsFromIssuanceOfSubordinatedLongTermDebt	30000000	USD
CY2018	us-gaap	Proceeds From Issuance Of Subordinated Long Term Debt ProceedsFromIssuanceOfSubordinatedLongTermDebt	0	USD
CY2020	us-gaap	Repayments Of Convertible Debt RepaymentsOfConvertibleDebt	-132000	USD
CY2019	us-gaap	Repayments Of Convertible Debt RepaymentsOfConvertibleDebt	0	USD
CY2018	us-gaap	Repayments Of Convertible Debt RepaymentsOfConvertibleDebt	0	USD
CY2020	us-gaap	Proceeds From Bank Debt ProceedsFromBankDebt	259600000	USD
CY2019	us-gaap	Proceeds From Bank Debt ProceedsFromBankDebt	0	USD
CY2018	us-gaap	Proceeds From Bank Debt ProceedsFromBankDebt	0	USD
CY2020	us-gaap	Repayments Of Bank Debt RepaymentsOfBankDebt	-210900000	USD
CY2019	us-gaap	Repayments Of Bank Debt RepaymentsOfBankDebt	0	USD
CY2018	us-gaap	Repayments Of Bank Debt RepaymentsOfBankDebt	0	USD
CY2020	us-gaap	Proceeds From Stock Options Exercised ProceedsFromStockOptionsExercised	0	USD
CY2019	us-gaap	Proceeds From Stock Options Exercised ProceedsFromStockOptionsExercised	0	USD
CY2018	us-gaap	Proceeds From Stock Options Exercised ProceedsFromStockOptionsExercised	10310	USD
CY2020	us-gaap	Proceeds From Stock Plans ProceedsFromStockPlans	12968	USD
CY2019	us-gaap	Proceeds From Stock Plans ProceedsFromStockPlans	52868	USD
CY2018	us-gaap	Proceeds From Stock Plans ProceedsFromStockPlans	12196	USD
CY2020	us-gaap	Payments Of Dividends Common Stock PaymentsOfDividendsCommonStock	1301254	USD
CY2019	us-gaap	Payments Of Dividends Common Stock PaymentsOfDividendsCommonStock	1123219	USD
CY2018	us-gaap	Payments Of Dividends Common Stock PaymentsOfDividendsCommonStock	1063626	USD
CY2020	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	192367678	USD
CY2019	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	35467314	USD
CY2018	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	39952736	USD
CY2020	us-gaap	Cash And Cash Equivalents Period Increase Decrease CashAndCashEquivalentsPeriodIncreaseDecrease	5489098	USD
CY2019	us-gaap	Cash And Cash Equivalents Period Increase Decrease CashAndCashEquivalentsPeriodIncreaseDecrease	-169599	USD
CY2018	us-gaap	Cash And Cash Equivalents Period Increase Decrease CashAndCashEquivalentsPeriodIncreaseDecrease	2386286	USD
CY2019Q4	us-gaap	Cash And Cash Equivalents At Carrying Value CashAndCashEquivalentsAtCarryingValue	12536311	USD
CY2018Q4	us-gaap	Cash And Cash Equivalents At Carrying Value CashAndCashEquivalentsAtCarryingValue	12705910	USD
CY2017Q4	us-gaap	Cash And Cash Equivalents At Carrying Value CashAndCashEquivalentsAtCarryingValue	10319624	USD
CY2020Q4	us-gaap	Cash And Cash Equivalents At Carrying Value CashAndCashEquivalentsAtCarryingValue	18025409	USD
CY2019Q4	us-gaap	Cash And Cash Equivalents At Carrying Value CashAndCashEquivalentsAtCarryingValue	12536311	USD
CY2018Q4	us-gaap	Cash And Cash Equivalents At Carrying Value CashAndCashEquivalentsAtCarryingValue	12705910	USD
CY2020	us-gaap	Interest Paid InterestPaid	6834112	USD
CY2019	us-gaap	Interest Paid InterestPaid	7882527	USD
CY2018	us-gaap	Interest Paid InterestPaid	5574723	USD
CY2020	us-gaap	Income Taxes Paid IncomeTaxesPaid	1475401	USD
CY2019	us-gaap	Income Taxes Paid IncomeTaxesPaid	1764541	USD
CY2018	us-gaap	Income Taxes Paid IncomeTaxesPaid	1521811	USD
CY2020	us-gaap	Transfer Of Portfolio Loans And Leases To Held For Sale1 TransferOfPortfolioLoansAndLeasesToHeldForSale1	368510	USD
CY2019	us-gaap	Transfer Of Portfolio Loans And Leases To Held For Sale1 TransferOfPortfolioLoansAndLeasesToHeldForSale1	832800	USD
CY2018	us-gaap	Transfer Of Portfolio Loans And Leases To Held For Sale1 TransferOfPortfolioLoansAndLeasesToHeldForSale1	435550	USD
CY2020	us-gaap	Other Comprehensive Income Loss Available For Sale Securities Adjustment Net Of Tax OtherComprehensiveIncomeLossAvailableForSaleSecuritiesAdjustmentNetOfTax	-8473423	USD
CY2019	us-gaap	Other Comprehensive Income Loss Available For Sale Securities Adjustment Net Of Tax OtherComprehensiveIncomeLossAvailableForSaleSecuritiesAdjustmentNetOfTax	-4495436	USD
CY2018	us-gaap	Other Comprehensive Income Loss Available For Sale Securities Adjustment Net Of Tax OtherComprehensiveIncomeLossAvailableForSaleSecuritiesAdjustmentNetOfTax	3571122	USD
CY2020	sfdl	Cash Equivalents Original Maturity Period Maximum CashEquivalentsOriginalMaturityPeriodMaximum	P3M
CY2020	sfdl	Investor Funding Period InvestorFundingPeriod	P30D
CY2020	us-gaap	Revenue Recognition Interest RevenueRecognitionInterest	<div style="margin-top:12pt;text-align:justify"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-style:italic;font-weight:700;line-height:120%">Interest Income</span></div><div style="margin-top:12pt;text-align:justify"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">Interest on loans is accrued and credited to income monthly based on the principal balance outstanding and the contractual rate on the loan. The Company places loans on non-accrual status when they become greater than 90 days delinquent or when, in the opinion of management, full collection of principal or interest is unlikely. When interest accrual is discontinued, all unpaid accrued interest is reversed. Interest income is subsequently recognized only to the extent cash payments are received first to principal and then to interest income. The loans are returned to an accrual status when full collection of principal and interest appears likely.</span></div>
CY2020	sfdl	Loans And Leases Receivable Placed On Nonaccrual Status Period Delinquent LoansAndLeasesReceivablePlacedOnNonaccrualStatusPeriodDelinquent	P90D
CY2020	us-gaap	Advertising Expense AdvertisingExpense	1100000	USD
CY2019	us-gaap	Advertising Expense AdvertisingExpense	796000	USD
CY2018	us-gaap	Advertising Expense AdvertisingExpense	547000	USD
CY2020	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	7050604	USD
CY2020	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	3212996	shares
CY2020	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	2.19
CY2020	us-gaap	Dilutive Securities Effect On Basic Earnings Per Share Other DilutiveSecuritiesEffectOnBasicEarningsPerShareOther	0	USD
CY2020	us-gaap	Incremental Common Shares Attributable To Conversion Of Debt Securities IncrementalCommonSharesAttributableToConversionOfDebtSecurities	0	shares
CY2020	sfdl	Dilutive Securities Common Shares Attributable To Conversion Of Debt Securities Effect On Basic Earnings Per Share DilutiveSecuritiesCommonSharesAttributableToConversionOfDebtSecuritiesEffectOnBasicEarningsPerShare	0
CY2020	us-gaap	Net Income Loss Available To Common Stockholders Diluted NetIncomeLossAvailableToCommonStockholdersDiluted	7050604	USD
CY2020	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	3212996	shares
CY2019	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	2.64
CY2020	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	2.19
CY2019	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	7794487	USD
CY2019	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	2955737	shares
CY2019	us-gaap	Dilutive Securities Effect On Basic Earnings Per Share Other DilutiveSecuritiesEffectOnBasicEarningsPerShareOther	362640	USD
CY2019	us-gaap	Incremental Common Shares Attributable To Conversion Of Debt Securities IncrementalCommonSharesAttributableToConversionOfDebtSecurities	302200	shares
CY2019	sfdl	Dilutive Securities Common Shares Attributable To Conversion Of Debt Securities Effect On Basic Earnings Per Share DilutiveSecuritiesCommonSharesAttributableToConversionOfDebtSecuritiesEffectOnBasicEarningsPerShare	-0.14
CY2019	us-gaap	Net Income Loss Available To Common Stockholders Diluted NetIncomeLossAvailableToCommonStockholdersDiluted	8157127	USD
CY2019	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	3257937	shares
CY2019	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	2.50
CY2020	us-gaap	Use Of Estimates UseOfEstimates	.
CY2020	us-gaap	Concentration Risk Credit Risk ConcentrationRiskCreditRisk	Risks and UncertaintiesIn the normal course of its business, the Company encounters two significant types of risk: economic and regulatory. There are three main components of economic risk: interest rate risk, credit risk, and market risk. The Company is subject to interest rate risk to the degree that its interest-bearing liabilities mature or reprice at different speeds, or on different bases, than its interest-earning assets. Credit risk is the risk of default on the Company’s loan portfolio that results from borrowers’ inability or unwillingness to make contractually required payments. Market risk reflects changes in the value of collateral underlying loans receivable, the valuation of real estate held by the Company, and the valuation of loans held for sale and securities available for sale. The Company is subject to the regulations of various government agencies. These regulations can and do change significantly from period to period. The Company also undergoes periodic examinations by the bank regulatory agencies, which may subject it to further changes with respect to asset valuations, amounts of required loss allowances, and operating restrictions, resulting from the regulators’ judgments based on information available to them at the time of the
CY2020	us-gaap	Prior Period Reclassification Adjustment Description PriorPeriodReclassificationAdjustmentDescription	lassificationsCertain amounts in prior years’ consolidated financial statements have been reclassified to conform to current period classifications.
CY2020Q4	us-gaap	Available For Sale Securities Amortized Cost AvailableForSaleSecuritiesAmortizedCost	572137595	USD
CY2020	us-gaap	Available For Sale Securities Gross Unrealized Gains AvailableForSaleSecuritiesGrossUnrealizedGains	19456692	USD
CY2020	us-gaap	Available For Sale Securities Gross Unrealized Loss AvailableForSaleSecuritiesGrossUnrealizedLoss	2269886	USD
CY2020Q4	us-gaap	Available For Sale Securities AvailableForSaleSecurities	589324401	USD
CY2019Q4	us-gaap	Available For Sale Securities Amortized Cost AvailableForSaleSecuritiesAmortizedCost	408695280	USD
CY2019	us-gaap	Available For Sale Securities Gross Unrealized Gains AvailableForSaleSecuritiesGrossUnrealizedGains	8410493	USD
CY2019	us-gaap	Available For Sale Securities Gross Unrealized Loss AvailableForSaleSecuritiesGrossUnrealizedLoss	2460933	USD
CY2019Q4	us-gaap	Available For Sale Securities AvailableForSaleSecurities	414644840	USD
CY2020Q4	us-gaap	Available For Sale Securities Debt Maturities Within One Year Amortized Cost AvailableForSaleSecuritiesDebtMaturitiesWithinOneYearAmortizedCost	64354	USD
CY2020Q4	us-gaap	Available For Sale Securities Debt Maturities Within One Year Fair Value AvailableForSaleSecuritiesDebtMaturitiesWithinOneYearFairValue	64197	USD
CY2020Q4	us-gaap	Available For Sale Securities Debt Maturities After One Through Five Years Amortized Cost AvailableForSaleSecuritiesDebtMaturitiesAfterOneThroughFiveYearsAmortizedCost	7995095	USD
CY2020Q4	us-gaap	Available For Sale Securities Debt Maturities After One Through Five Years Fair Value AvailableForSaleSecuritiesDebtMaturitiesAfterOneThroughFiveYearsFairValue	8022724	USD
CY2020Q4	us-gaap	Available For Sale Securities Debt Maturities After Five Through Ten Years Amortized Cost AvailableForSaleSecuritiesDebtMaturitiesAfterFiveThroughTenYearsAmortizedCost	77877630	USD
CY2020Q4	us-gaap	Available For Sale Securities Debt Maturities After Five Through Ten Years Fair Value AvailableForSaleSecuritiesDebtMaturitiesAfterFiveThroughTenYearsFairValue	78435507	USD
CY2020Q4	us-gaap	Available For Sale Securities Debt Maturities After Ten Years Amortized Cost AvailableForSaleSecuritiesDebtMaturitiesAfterTenYearsAmortizedCost	218345636	USD
CY2020Q4	us-gaap	Available For Sale Securities Debt Maturities After Ten Years Fair Value AvailableForSaleSecuritiesDebtMaturitiesAfterTenYearsFairValue	225028959	USD
CY2020Q4	us-gaap	Available For Sale Debt Securities Amortized Cost Basis AvailableForSaleDebtSecuritiesAmortizedCostBasis	572137595	USD
CY2020Q4	us-gaap	Available For Sale Securities Debt Maturities Without Single Maturity Date Fair Value AvailableForSaleSecuritiesDebtMaturitiesWithoutSingleMaturityDateFairValue	589324401	USD
CY2020Q4	sfdl	Available For Sale Securities Pledged As Collateral Amortized Cost Basis AvailableForSaleSecuritiesPledgedAsCollateralAmortizedCostBasis	263300000	USD
CY2020Q4	sfdl	Afs Securities Pledgedas Collateral Fair Value AFSSecuritiesPledgedasCollateralFairValue	274400000	USD
CY2019Q4	sfdl	Available For Sale Securities Pledged As Collateral Amortized Cost Basis AvailableForSaleSecuritiesPledgedAsCollateralAmortizedCostBasis	171400000	USD
CY2019Q4	sfdl	Afs Securities Pledgedas Collateral Fair Value AFSSecuritiesPledgedasCollateralFairValue	173100000	USD
CY2020	sfdl	Proceeds From Sale Of Available For Sale Securities Including Mortgage Backed Securities ProceedsFromSaleOfAvailableForSaleSecuritiesIncludingMortgageBackedSecurities	25000000.0	USD
CY2019	sfdl	Proceeds From Sale Of Available For Sale Securities Including Mortgage Backed Securities ProceedsFromSaleOfAvailableForSaleSecuritiesIncludingMortgageBackedSecurities	96500000	USD
CY2018	sfdl	Proceeds From Sale Of Available For Sale Securities Including Mortgage Backed Securities ProceedsFromSaleOfAvailableForSaleSecuritiesIncludingMortgageBackedSecurities	33300000	USD
CY2020	us-gaap	Available For Sale Securities Gross Realized Gains AvailableForSaleSecuritiesGrossRealizedGains	1300000	USD
CY2019	us-gaap	Available For Sale Securities Gross Realized Gains AvailableForSaleSecuritiesGrossRealizedGains	1500000	USD
CY2018	us-gaap	Available For Sale Securities Gross Realized Gains AvailableForSaleSecuritiesGrossRealizedGains	700000	USD
CY2020	us-gaap	Available For Sale Securities Gross Realized Losses AvailableForSaleSecuritiesGrossRealizedLosses	0	USD
CY2019	us-gaap	Available For Sale Securities Gross Realized Losses AvailableForSaleSecuritiesGrossRealizedLosses	636000	USD
CY2018	us-gaap	Available For Sale Securities Gross Realized Losses AvailableForSaleSecuritiesGrossRealizedLosses	159000	USD
CY2020Q4	us-gaap	Available For Sale Securities Continuous Unrealized Loss Position Less Than Twelve Months Fair Value AvailableForSaleSecuritiesContinuousUnrealizedLossPositionLessThanTwelveMonthsFairValue	106073904	USD
CY2020Q4	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position Less Than12 Months Accumulated Loss DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss	1430106	USD
CY2020Q4	us-gaap	Available For Sale Securities Continuous Unrealized Loss Position Twelve Months Or Longer Fair Value AvailableForSaleSecuritiesContinuousUnrealizedLossPositionTwelveMonthsOrLongerFairValue	82910611	USD
CY2020Q4	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position12 Months Or Longer Accumulated Loss DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLongerAccumulatedLoss	839780	USD
CY2020Q4	us-gaap	Available For Sale Securities Continuous Unrealized Loss Position Fair Value AvailableForSaleSecuritiesContinuousUnrealizedLossPositionFairValue	188984515	USD
CY2020Q4	us-gaap	Debt Securities Available For Sale Unrealized Loss Position Accumulated Loss DebtSecuritiesAvailableForSaleUnrealizedLossPositionAccumulatedLoss	2269886	USD
CY2019Q4	us-gaap	Available For Sale Securities Continuous Unrealized Loss Position Less Than Twelve Months Fair Value AvailableForSaleSecuritiesContinuousUnrealizedLossPositionLessThanTwelveMonthsFairValue	113060506	USD
CY2019Q4	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position Less Than12 Months Accumulated Loss DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss	1485802	USD
CY2019Q4	us-gaap	Available For Sale Securities Continuous Unrealized Loss Position Twelve Months Or Longer Fair Value AvailableForSaleSecuritiesContinuousUnrealizedLossPositionTwelveMonthsOrLongerFairValue	65523232	USD
CY2019Q4	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position12 Months Or Longer Accumulated Loss DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLongerAccumulatedLoss	975131	USD
CY2019Q4	us-gaap	Available For Sale Securities Continuous Unrealized Loss Position Fair Value AvailableForSaleSecuritiesContinuousUnrealizedLossPositionFairValue	178583738	USD
CY2019Q4	us-gaap	Debt Securities Available For Sale Unrealized Loss Position Accumulated Loss DebtSecuritiesAvailableForSaleUnrealizedLossPositionAccumulatedLoss	2460933	USD
CY2020Q4	sfdl	Available For Sale Percent Of Unrealized Losses For Securities In Continuous Loss Position12 Months Or Longer AvailableForSalePercentOfUnrealizedLossesForSecuritiesInContinuousLossPosition12MonthsOrLonger	0.370
CY2019Q4	sfdl	Available For Sale Percent Of Unrealized Losses For Securities In Continuous Loss Position12 Months Or Longer AvailableForSalePercentOfUnrealizedLossesForSecuritiesInContinuousLossPosition12MonthsOrLonger	0.396
CY2020Q4	us-gaap	Availableforsale Securities In Unrealized Loss Positions Qualitative Disclosure Number Of Positions1 AvailableforsaleSecuritiesInUnrealizedLossPositionsQualitativeDisclosureNumberOfPositions1	88	security
CY2019Q4	us-gaap	Availableforsale Securities In Unrealized Loss Positions Qualitative Disclosure Number Of Positions1 AvailableforsaleSecuritiesInUnrealizedLossPositionsQualitativeDisclosureNumberOfPositions1	69	security
CY2020Q4	us-gaap	Held To Maturity Securities Amortized Cost Before Other Than Temporary Impairment HeldToMaturitySecuritiesAmortizedCostBeforeOtherThanTemporaryImpairment	18254394	USD
CY2020	sfdl	Heldtomaturitygrossunrealizedgains Heldtomaturitygrossunrealizedgains	984015	USD
CY2020	sfdl	Heldtomaturitygrossunrealizedlosses Heldtomaturitygrossunrealizedlosses	33122	USD
CY2020Q4	us-gaap	Held To Maturity Securities Fair Value HeldToMaturitySecuritiesFairValue	19205287	USD
CY2019Q4	us-gaap	Held To Maturity Securities Amortized Cost Before Other Than Temporary Impairment HeldToMaturitySecuritiesAmortizedCostBeforeOtherThanTemporaryImpairment	19246935	USD
CY2019	sfdl	Heldtomaturitygrossunrealizedgains Heldtomaturitygrossunrealizedgains	560067	USD
CY2019	sfdl	Heldtomaturitygrossunrealizedlosses Heldtomaturitygrossunrealizedlosses	1161	USD
CY2019Q4	us-gaap	Held To Maturity Securities Fair Value HeldToMaturitySecuritiesFairValue	19805841	USD
CY2020Q4	us-gaap	Held To Maturity Securities Restricted HeldToMaturitySecuritiesRestricted	13400000	USD
CY2020Q4	sfdl	Heldtomaturitypledgedascollateralfairvalue Heldtomaturitypledgedascollateralfairvalue	14300000	USD
CY2019Q4	sfdl	Heldtomaturitypledgedascollateralfairvalue Heldtomaturitypledgedascollateralfairvalue	17500000	USD
CY2020Q4	us-gaap	Held To Maturity Securities Continuous Unrealized Loss Position Less Than Twelve Months Fair Value HeldToMaturitySecuritiesContinuousUnrealizedLossPositionLessThanTwelveMonthsFairValue	3692780	USD
CY2020Q4	us-gaap	Held To Maturity Securities Continuous Unrealized Loss Position Less Than12 Months Accumulated Loss HeldToMaturitySecuritiesContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss	32583	USD
CY2020Q4	us-gaap	Held To Maturity Securities Continuous Unrealized Loss Position Twelve Months Or Longer Fair Value HeldToMaturitySecuritiesContinuousUnrealizedLossPositionTwelveMonthsOrLongerFairValue	787503	USD
CY2020Q4	us-gaap	Held To Maturity Securities Continuous Unrealized Loss Position12 Months Or Longer Accumulated Loss HeldToMaturitySecuritiesContinuousUnrealizedLossPosition12MonthsOrLongerAccumulatedLoss	539	USD
CY2020Q4	us-gaap	Held To Maturity Securities Continuous Unrealized Loss Position Fair Value HeldToMaturitySecuritiesContinuousUnrealizedLossPositionFairValue	4480283	USD
CY2020Q4	us-gaap	Held To Maturity Securities Continuous Unrealized Loss Position Accumulated Loss HeldToMaturitySecuritiesContinuousUnrealizedLossPositionAccumulatedLoss	33122	USD
CY2020Q4	us-gaap	Notes Receivable Gross NotesReceivableGross	500352711	USD
CY2019Q4	us-gaap	Notes Receivable Gross NotesReceivableGross	468520411	USD
CY2020Q4	us-gaap	Loans Receivable Held For Sale Net Not Part Of Disposal Group LoansReceivableHeldForSaleNetNotPartOfDisposalGroup	5693400	USD
CY2019Q4	us-gaap	Loans Receivable Held For Sale Net Not Part Of Disposal Group LoansReceivableHeldForSaleNetNotPartOfDisposalGroup	3990606	USD
CY2020Q4	sfdl	Financing Receivable Gross And Loans Receivable Held For Sale Net FinancingReceivableGrossAndLoansReceivableHeldForSaleNet	506046111	USD
CY2019Q4	sfdl	Financing Receivable Gross And Loans Receivable Held For Sale Net FinancingReceivableGrossAndLoansReceivableHeldForSaleNet	472511017	USD
CY2020Q4	us-gaap	Loans And Leases Receivable Allowance LoansAndLeasesReceivableAllowance	12842896	USD
CY2019Q4	us-gaap	Loans And Leases Receivable Allowance LoansAndLeasesReceivableAllowance	9225574	USD
CY2020Q4	us-gaap	Loans And Leases Receivable Loans In Process LoansAndLeasesReceivableLoansInProcess	12197417	USD
CY2019Q4	us-gaap	Loans And Leases Receivable Loans In Process LoansAndLeasesReceivableLoansInProcess	9957140	USD
CY2020Q4	us-gaap	Loans And Leases Receivable Deferred Income LoansAndLeasesReceivableDeferredIncome	1838426	USD
CY2019Q4	us-gaap	Loans And Leases Receivable Deferred Income LoansAndLeasesReceivableDeferredIncome	469568	USD
CY2020Q4	sfdl	Loans Receivable Allowance Loans In Process And Deferred Loan Fees LoansReceivableAllowanceLoansInProcessAndDeferredLoanFees	26878739	USD
CY2019Q4	sfdl	Loans Receivable Allowance Loans In Process And Deferred Loan Fees LoansReceivableAllowanceLoansInProcessAndDeferredLoanFees	19652282	USD
CY2020Q4	us-gaap	Notes Receivable Net NotesReceivableNet	479167372	USD
CY2020Q4	us-gaap	Financing Receivable Allowance For Credit Losses Individually Evaluated For Impairment1 FinancingReceivableAllowanceForCreditLossesIndividuallyEvaluatedForImpairment1	0	USD
CY2020Q4	us-gaap	Notes Receivable Gross NotesReceivableGross	500352711	USD
CY2019Q4	us-gaap	Financing Receivable Recorded Investment Past Due FinancingReceivableRecordedInvestmentPastDue	6668150	USD
CY2019Q4	us-gaap	Notes Receivable Net NotesReceivableNet	452858735	USD
CY2020Q4	us-gaap	Notes Receivable Gross NotesReceivableGross	500352711	USD
CY2019Q4	us-gaap	Notes Receivable Gross NotesReceivableGross	468520411	USD
CY2020Q4	us-gaap	Financing Receivable Recorded Investment Past Due FinancingReceivableRecordedInvestmentPastDue	2417185	USD
CY2020Q4	us-gaap	Financing Receivable Recorded Investment Current FinancingReceivableRecordedInvestmentCurrent	497935526	USD
CY2019Q4	us-gaap	Financing Receivable Recorded Investment Current FinancingReceivableRecordedInvestmentCurrent	461852261	USD
CY2019Q4	us-gaap	Notes Receivable Gross NotesReceivableGross	468520411	USD
CY2020Q4	us-gaap	Financing Receivable Recorded Investment Nonaccrual Status FinancingReceivableRecordedInvestmentNonaccrualStatus	3125472	USD
CY2020Q4	sfdl	Financing Receivable Recorded Investment Nonaccrual Status Percentage FinancingReceivableRecordedInvestmentNonaccrualStatusPercentage	0.007
CY2019Q4	us-gaap	Financing Receivable Recorded Investment Nonaccrual Status FinancingReceivableRecordedInvestmentNonaccrualStatus	3436406	USD
CY2019Q4	sfdl	Financing Receivable Recorded Investment Nonaccrual Status Percentage FinancingReceivableRecordedInvestmentNonaccrualStatusPercentage	0.007
CY2020	sfdl	Financing Receivable Recorded Investment In Non Accrual Status Increase Decrease FinancingReceivableRecordedInvestmentInNonAccrualStatusIncreaseDecrease	-310934	USD
CY2020Q4	us-gaap	Allowance For Doubtful Accounts Receivable AllowanceForDoubtfulAccountsReceivable	12842896	USD
CY2020	sfdl	Financing Receivable Recorded Investment In Non Accrual Status Percent Increase Decrease FinancingReceivableRecordedInvestmentInNonAccrualStatusPercentIncreaseDecrease	-0.090
CY2019Q4	us-gaap	Allowance For Doubtful Accounts Receivable AllowanceForDoubtfulAccountsReceivable	9225574	USD
CY2020	us-gaap	Provision For Doubtful Accounts ProvisionForDoubtfulAccounts	3600000	USD
CY2020	us-gaap	Allowance For Doubtful Accounts Receivable Write Offs AllowanceForDoubtfulAccountsReceivableWriteOffs	281270	USD
CY2020	us-gaap	Allowance For Doubtful Accounts Receivable Recoveries AllowanceForDoubtfulAccountsReceivableRecoveries	298592	USD
CY2018Q4	us-gaap	Allowance For Doubtful Accounts Receivable AllowanceForDoubtfulAccountsReceivable	9171717	USD
CY2019	us-gaap	Provision For Doubtful Accounts ProvisionForDoubtfulAccounts	375000	USD
CY2019	us-gaap	Allowance For Doubtful Accounts Receivable Write Offs AllowanceForDoubtfulAccountsReceivableWriteOffs	985317	USD
CY2019	us-gaap	Allowance For Doubtful Accounts Receivable Recoveries AllowanceForDoubtfulAccountsReceivableRecoveries	664174	USD
CY2019Q4	us-gaap	Allowance For Doubtful Accounts Receivable AllowanceForDoubtfulAccountsReceivable	9225574	USD
CY2017Q4	us-gaap	Allowance For Doubtful Accounts Receivable AllowanceForDoubtfulAccountsReceivable	8221618	USD
CY2018	us-gaap	Provision For Doubtful Accounts ProvisionForDoubtfulAccounts	925000	USD
CY2018	us-gaap	Allowance For Doubtful Accounts Receivable Write Offs AllowanceForDoubtfulAccountsReceivableWriteOffs	655785	USD
CY2018	us-gaap	Allowance For Doubtful Accounts Receivable Recoveries AllowanceForDoubtfulAccountsReceivableRecoveries	680884	USD
CY2018Q4	us-gaap	Allowance For Doubtful Accounts Receivable AllowanceForDoubtfulAccountsReceivable	9171717	USD
CY2020	us-gaap	Impaired Financing Receivable Average Recorded Investment ImpairedFinancingReceivableAverageRecordedInvestment	3900000	USD
CY2020Q4	us-gaap	Financing Receivable Allowance For Credit Losses Collectively Evaluated For Impairment FinancingReceivableAllowanceForCreditLossesCollectivelyEvaluatedForImpairment	12842896	USD
CY2020Q4	us-gaap	Financing Receivable Allowance For Credit Losses FinancingReceivableAllowanceForCreditLosses	12842896	USD
CY2020Q4	us-gaap	Financing Receivable Individually Evaluated For Impairment FinancingReceivableIndividuallyEvaluatedForImpairment	2219330	USD
CY2020Q4	us-gaap	Financing Receivable Collectively Evaluated For Impairment FinancingReceivableCollectivelyEvaluatedForImpairment	498133381	USD
CY2020Q4	us-gaap	Notes Receivable Gross NotesReceivableGross	500352711	USD
CY2020	sfdl	Loans And Leases Receivable Valuation Period For New Appraisal LoansAndLeasesReceivableValuationPeriodForNewAppraisal	P24M
CY2019	us-gaap	Impaired Financing Receivable Average Recorded Investment ImpairedFinancingReceivableAverageRecordedInvestment	6400000	USD
CY2020Q4	us-gaap	Impaired Financing Receivable Recorded Investment ImpairedFinancingReceivableRecordedInvestment	2219330	USD
CY2020Q4	us-gaap	Impaired Financing Receivable Unpaid Principal Balance ImpairedFinancingReceivableUnpaidPrincipalBalance	3268049	USD
CY2020Q4	us-gaap	Impaired Financing Receivable Related Allowance ImpairedFinancingReceivableRelatedAllowance	0	USD
CY2020	us-gaap	Impaired Financing Receivable Average Recorded Investment ImpairedFinancingReceivableAverageRecordedInvestment	3864751	USD
CY2020	us-gaap	Impaired Financing Receivable Interest Income Accrual Method ImpairedFinancingReceivableInterestIncomeAccrualMethod	82925	USD
CY2019Q4	us-gaap	Impaired Financing Receivable Recorded Investment ImpairedFinancingReceivableRecordedInvestment	3229883	USD
CY2019Q4	us-gaap	Impaired Financing Receivable Unpaid Principal Balance ImpairedFinancingReceivableUnpaidPrincipalBalance	4305403	USD
CY2019Q4	us-gaap	Impaired Financing Receivable Related Allowance ImpairedFinancingReceivableRelatedAllowance	0	USD
CY2019	us-gaap	Impaired Financing Receivable Average Recorded Investment ImpairedFinancingReceivableAverageRecordedInvestment	6394612	USD
CY2019	us-gaap	Impaired Financing Receivable Interest Income Accrual Method ImpairedFinancingReceivableInterestIncomeAccrualMethod	54372	USD
CY2018Q4	us-gaap	Impaired Financing Receivable Recorded Investment ImpairedFinancingReceivableRecordedInvestment	9364125	USD
CY2018Q4	us-gaap	Impaired Financing Receivable Unpaid Principal Balance ImpairedFinancingReceivableUnpaidPrincipalBalance	11299728	USD
CY2018Q4	us-gaap	Impaired Financing Receivable Related Allowance ImpairedFinancingReceivableRelatedAllowance	738662	USD
CY2018	us-gaap	Impaired Financing Receivable Average Recorded Investment ImpairedFinancingReceivableAverageRecordedInvestment	11026748	USD
CY2018	us-gaap	Impaired Financing Receivable Interest Income Accrual Method ImpairedFinancingReceivableInterestIncomeAccrualMethod	328920	USD
CY2020	us-gaap	Financing Receivable Modifications Number Of Contracts2 FinancingReceivableModificationsNumberOfContracts2	3
CY2020Q4	sfdl	Tdrs Included In Impaired Loans TdrsIncludedInImpairedLoans	315000	USD
CY2019	us-gaap	Financing Receivable Modifications Number Of Contracts2 FinancingReceivableModificationsNumberOfContracts2	5
CY2019Q4	sfdl	Tdrs Included In Impaired Loans TdrsIncludedInImpairedLoans	825000	USD
CY2020Q4	sfdl	Financing Receivable Modifications Subsequent Default Aggregate Number Of Contracts FinancingReceivableModificationsSubsequentDefaultAggregateNumberOfContracts	0	loan
CY2018Q4	sfdl	Financing Receivable Modifications Subsequent Default Aggregate Number Of Contracts FinancingReceivableModificationsSubsequentDefaultAggregateNumberOfContracts	1	loan
CY2019	us-gaap	Operating Leases Rent Expense Net OperatingLeasesRentExpenseNet	460000	USD
CY2020	sfdl	Nonperforming Loans Accrual Status Minimum Consecutive Payments NonperformingLoansAccrualStatusMinimumConsecutivePayments	6	payments
CY2020Q4	us-gaap	Property Plant And Equipment Gross PropertyPlantAndEquipmentGross	48139208	USD
CY2019Q4	us-gaap	Property Plant And Equipment Gross PropertyPlantAndEquipmentGross	47544896	USD
CY2020Q4	us-gaap	Accumulated Depreciation Depletion And Amortization Property Plant And Equipment AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment	21563951	USD
CY2019Q4	us-gaap	Accumulated Depreciation Depletion And Amortization Property Plant And Equipment AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment	20325013	USD
CY2020Q4	us-gaap	Property Plant And Equipment Net PropertyPlantAndEquipmentNet	26575257	USD
CY2019Q4	us-gaap	Property Plant And Equipment Net PropertyPlantAndEquipmentNet	27219883	USD
CY2020	us-gaap	Depreciation And Amortization DepreciationAndAmortization	1900000	USD
CY2019	us-gaap	Depreciation And Amortization DepreciationAndAmortization	1600000	USD
CY2018	us-gaap	Depreciation And Amortization DepreciationAndAmortization	1500000	USD
CY2020Q4	us-gaap	Operating Lease Right Of Use Asset OperatingLeaseRightOfUseAsset	2400000	USD
CY2020Q4	us-gaap	Operating Lease Liability OperatingLeaseLiability	2400000	USD
CY2020	us-gaap	Operating Leases Rent Expense Net OperatingLeasesRentExpenseNet	461000	USD
CY2020Q4	us-gaap	Federal Home Loan Bank Stock FederalHomeLoanBankStock	2400000	USD
CY2018	us-gaap	Operating Leases Rent Expense Net OperatingLeasesRentExpenseNet	454000	USD
CY2020Q4	sfdl	Operating Leases Number Of Lease Agreements OperatingLeasesNumberOfLeaseAgreements	5	lease_agreement
CY2019Q4	us-gaap	Federal Home Loan Bank Stock FederalHomeLoanBankStock	2500000	USD
CY2020Q4	us-gaap	Other Real Estate And Foreclosed Assets OtherRealEstateAndForeclosedAssets	499000	USD
CY2019Q4	us-gaap	Other Real Estate And Foreclosed Assets OtherRealEstateAndForeclosedAssets	678000	USD
CY2019Q4	us-gaap	Other Real Estate And Foreclosed Assets OtherRealEstateAndForeclosedAssets	677740	USD
CY2018Q4	us-gaap	Other Real Estate And Foreclosed Assets OtherRealEstateAndForeclosedAssets	722442	USD
CY2017Q4	us-gaap	Other Real Estate And Foreclosed Assets OtherRealEstateAndForeclosedAssets	1115671	USD
CY2020	sfdl	Other Real Estate Foreclosed Assets And Repossessed Assets Additions OtherRealEstateForeclosedAssetsAndRepossessedAssetsAdditions	368510	USD
CY2019	sfdl	Other Real Estate Foreclosed Assets And Repossessed Assets Additions OtherRealEstateForeclosedAssetsAndRepossessedAssetsAdditions	832800	USD
CY2018	sfdl	Other Real Estate Foreclosed Assets And Repossessed Assets Additions OtherRealEstateForeclosedAssetsAndRepossessedAssetsAdditions	435550	USD
CY2020	sfdl	Other Real Estate Foreclosed Assets And Repossessed Assets Sales OtherRealEstateForeclosedAssetsAndRepossessedAssetsSales	532640	USD
CY2019	sfdl	Other Real Estate Foreclosed Assets And Repossessed Assets Sales OtherRealEstateForeclosedAssetsAndRepossessedAssetsSales	855502	USD
CY2018	sfdl	Other Real Estate Foreclosed Assets And Repossessed Assets Sales OtherRealEstateForeclosedAssetsAndRepossessedAssetsSales	772779	USD
CY2020	sfdl	Other Real Estate Foreclosed Assets And Repossessed Assets Write Downs OtherRealEstateForeclosedAssetsAndRepossessedAssetsWriteDowns	15000	USD
CY2019	sfdl	Other Real Estate Foreclosed Assets And Repossessed Assets Write Downs OtherRealEstateForeclosedAssetsAndRepossessedAssetsWriteDowns	22000	USD
CY2018	sfdl	Other Real Estate Foreclosed Assets And Repossessed Assets Write Downs OtherRealEstateForeclosedAssetsAndRepossessedAssetsWriteDowns	56000	USD
CY2020Q4	us-gaap	Other Real Estate And Foreclosed Assets OtherRealEstateAndForeclosedAssets	498610	USD
CY2019Q4	us-gaap	Other Real Estate And Foreclosed Assets OtherRealEstateAndForeclosedAssets	677740	USD
CY2018Q4	us-gaap	Other Real Estate And Foreclosed Assets OtherRealEstateAndForeclosedAssets	722442	USD
CY2020Q4	us-gaap	Demand Deposit Accounts DemandDepositAccounts	372070032	USD
CY2020Q4	us-gaap	Weighted Average Rate Domestic Deposit Checking WeightedAverageRateDomesticDepositChecking	0.0005
CY2019Q4	us-gaap	Demand Deposit Accounts DemandDepositAccounts	260135924	USD
CY2019Q4	us-gaap	Weighted Average Rate Domestic Deposit Checking WeightedAverageRateDomesticDepositChecking	0.0011
CY2020Q4	us-gaap	Deposits Money Market Deposits DepositsMoneyMarketDeposits	291067575	USD
CY2020Q4	us-gaap	Weighted Average Rate Domestic Deposit Money Market WeightedAverageRateDomesticDepositMoneyMarket	0.0016
CY2019Q4	us-gaap	Deposits Money Market Deposits DepositsMoneyMarketDeposits	230693518	USD
CY2019Q4	us-gaap	Weighted Average Rate Domestic Deposit Money Market WeightedAverageRateDomesticDepositMoneyMarket	0.0072
CY2020Q4	us-gaap	Deposits Savings Deposits DepositsSavingsDeposits	74433571	USD
CY2020Q4	us-gaap	Weighted Average Rate Domestic Deposit Savings WeightedAverageRateDomesticDepositSavings	0.0014
CY2019Q4	us-gaap	Deposits Savings Deposits DepositsSavingsDeposits	51124806	USD
CY2019Q4	us-gaap	Weighted Average Rate Domestic Deposit Savings WeightedAverageRateDomesticDepositSavings	0.0016
CY2020Q4	sfdl	Deposits Excluding Time Deposits DepositsExcludingTimeDeposits	737571178	USD
CY2020Q4	sfdl	Weighted Average Rate Domestic Deposit Excluding Time Deposits WeightedAverageRateDomesticDepositExcludingTimeDeposits	0.0010
CY2019Q4	sfdl	Deposits Excluding Time Deposits DepositsExcludingTimeDeposits	541954248	USD
CY2019Q4	sfdl	Weighted Average Rate Domestic Deposit Excluding Time Deposits WeightedAverageRateDomesticDepositExcludingTimeDeposits	0.0036
CY2020Q4	us-gaap	Time Deposits TimeDeposits	180525057	USD
CY2020Q4	us-gaap	Weighted Average Rate Domestic Deposit Certificates Of Deposit WeightedAverageRateDomesticDepositCertificatesOfDeposit	0.0077
CY2019Q4	us-gaap	Time Deposits TimeDeposits	229453234	USD
CY2019Q4	us-gaap	Weighted Average Rate Domestic Deposit Certificates Of Deposit WeightedAverageRateDomesticDepositCertificatesOfDeposit	0.0171
CY2020Q4	us-gaap	Deposits Deposits	918096235	USD
CY2020Q4	us-gaap	Weighted Average Rate Domestic Deposit WeightedAverageRateDomesticDeposit	0.0023
CY2019Q4	us-gaap	Deposits Deposits	771407482	USD
CY2019Q4	us-gaap	Weighted Average Rate Domestic Deposit WeightedAverageRateDomesticDeposit	0.0076
CY2020Q4	us-gaap	Interest Bearing Domestic Deposit Brokered InterestBearingDomesticDepositBrokered	16000000.0	USD
CY2019Q4	us-gaap	Interest Bearing Domestic Deposit Brokered InterestBearingDomesticDepositBrokered	34600000	USD
CY2020Q4	us-gaap	Weighted Average Rate Domestic Deposit Brokered WeightedAverageRateDomesticDepositBrokered	0.0037
CY2019Q4	us-gaap	Weighted Average Rate Domestic Deposit Brokered WeightedAverageRateDomesticDepositBrokered	0.0187
CY2020Q4	sfdl	Interest Bearing Domestic Deposit Maturities Brokered Next Twelve Months InterestBearingDomesticDepositMaturitiesBrokeredNextTwelveMonths	0	USD
CY2020Q4	us-gaap	Deposit Liabilities Reclassified As Loans Receivable1 DepositLiabilitiesReclassifiedAsLoansReceivable1	78000	USD
CY2020Q4	us-gaap	Time Deposits100000 Or More TimeDeposits100000OrMore	106800000	USD
CY2019Q4	us-gaap	Time Deposits100000 Or More TimeDeposits100000OrMore	144200000	USD
CY2020Q4	sfdl	Timedeposits250000ormore Timedeposits250000ormore	49600000	USD
CY2019Q4	sfdl	Timedeposits250000ormore Timedeposits250000ormore	77500000	USD
CY2020Q4	us-gaap	Time Deposit Maturities Year One TimeDepositMaturitiesYearOne	128758122	USD
CY2019Q4	us-gaap	Time Deposit Maturities Year One TimeDepositMaturitiesYearOne	149481000	USD
CY2020Q4	us-gaap	Time Deposit Maturities Year Two TimeDepositMaturitiesYearTwo	27550051	USD
CY2019Q4	us-gaap	Time Deposit Maturities Year Two TimeDepositMaturitiesYearTwo	42689147	USD
CY2020Q4	us-gaap	Time Deposit Maturities Year Three TimeDepositMaturitiesYearThree	10555458	USD
CY2019Q4	us-gaap	Time Deposit Maturities Year Three TimeDepositMaturitiesYearThree	18737910	USD
CY2020Q4	us-gaap	Time Deposit Maturities Year Four TimeDepositMaturitiesYearFour	10847730	USD
CY2019Q4	us-gaap	Time Deposit Maturities Year Four TimeDepositMaturitiesYearFour	3272862	USD
CY2020Q4	us-gaap	Time Deposit Maturities Year Five TimeDepositMaturitiesYearFive	2813696	USD
CY2019Q4	us-gaap	Time Deposit Maturities Year Five TimeDepositMaturitiesYearFive	15272315	USD
CY2020Q4	us-gaap	Time Deposits TimeDeposits	180525057	USD
CY2019Q4	us-gaap	Time Deposits TimeDeposits	229453234	USD
CY2020Q4	us-gaap	Federal Home Loan Bank Advances Maturities Summary Due Within One Year Of Balance Sheet Date FederalHomeLoanBankAdvancesMaturitiesSummaryDueWithinOneYearOfBalanceSheetDate	25000000	USD
CY2020Q4	us-gaap	Federal Home Loan Bank Advances Maturities Summary Average Interest Rate Of Amounts Due Within One Year Of Balance Sheet Date FederalHomeLoanBankAdvancesMaturitiesSummaryAverageInterestRateOfAmountsDueWithinOneYearOfBalanceSheetDate	0.0198
CY2020Q4	us-gaap	Federal Home Loan Bank Advances Maturities Summary Due From Two To Three Years Of Balance Sheet Date FederalHomeLoanBankAdvancesMaturitiesSummaryDueFromTwoToThreeYearsOfBalanceSheetDate	10000000	USD
CY2020Q4	us-gaap	Federal Home Loan Bank Advances Maturities Summary Average Interest Rate Two To Three Years From Balance Sheet Date FederalHomeLoanBankAdvancesMaturitiesSummaryAverageInterestRateTwoToThreeYearsFromBalanceSheetDate	0.0146
CY2020Q4	us-gaap	Advances From Federal Home Loan Banks AdvancesFromFederalHomeLoanBanks	35000000	USD
CY2020Q4	us-gaap	Federal Home Loan Bank Advances Activity For Year Average Interest Rate At Period End FederalHomeLoanBankAdvancesActivityForYearAverageInterestRateAtPeriodEnd	0.0183
CY2020Q4	sfdl	Federal Home Loan Bank Advances General Debt Obligations Disclosures Collateral Pledged Amortized Cost FederalHomeLoanBankAdvancesGeneralDebtObligationsDisclosuresCollateralPledgedAmortizedCost	104700000	USD
CY2020Q4	us-gaap	Federal Home Loan Bank Advances General Debt Obligations Disclosures Collateral Pledged1 FederalHomeLoanBankAdvancesGeneralDebtObligationsDisclosuresCollateralPledged1	106200000	USD
CY2019Q4	sfdl	Federal Home Loan Bank Advances General Debt Obligations Disclosures Collateral Pledged Amortized Cost FederalHomeLoanBankAdvancesGeneralDebtObligationsDisclosuresCollateralPledgedAmortizedCost	100500000	USD
CY2019Q4	us-gaap	Federal Home Loan Bank Advances General Debt Obligations Disclosures Collateral Pledged1 FederalHomeLoanBankAdvancesGeneralDebtObligationsDisclosuresCollateralPledged1	96700000	USD
CY2020Q4	us-gaap	Financial Instruments Owned And Pledged As Collateral At Fair Value FinancialInstrumentsOwnedAndPledgedAsCollateralAtFairValue	26800000	USD
CY2019Q4	sfdl	Financial Instruments Owned And Pledged As Collateral At Amortized Cost FinancialInstrumentsOwnedAndPledgedAsCollateralAtAmortizedCost	20400000	USD
CY2019Q4	us-gaap	Financial Instruments Owned And Pledged As Collateral At Fair Value FinancialInstrumentsOwnedAndPledgedAsCollateralAtFairValue	20500000	USD
CY2020	us-gaap	Repayments Of Federal Home Loan Bank Borrowings RepaymentsOfFederalHomeLoanBankBorrowings	0	USD
CY2020Q4	us-gaap	Federal Home Loan Bank Advances General Debt Obligations Disclosures Amount Of Available Unused Funds FederalHomeLoanBankAdvancesGeneralDebtObligationsDisclosuresAmountOfAvailableUnusedFunds	304300000	USD
CY2019Q4	us-gaap	Federal Home Loan Bank Advances General Debt Obligations Disclosures Amount Of Available Unused Funds FederalHomeLoanBankAdvancesGeneralDebtObligationsDisclosuresAmountOfAvailableUnusedFunds	259200000	USD
CY2020Q4	us-gaap	Other Borrowings OtherBorrowings	13100000	USD
CY2019Q4	us-gaap	Other Borrowings OtherBorrowings	11600000	USD
CY2020Q4	sfdl	Financial Instruments Owned And Pledged As Collateral At Amortized Cost FinancialInstrumentsOwnedAndPledgedAsCollateralAtAmortizedCost	26600000	USD
CY2020	us-gaap	Current Federal Tax Expense Benefit CurrentFederalTaxExpenseBenefit	1663883	USD
CY2019	us-gaap	Current Federal Tax Expense Benefit CurrentFederalTaxExpenseBenefit	1437595	USD
CY2018	us-gaap	Current Federal Tax Expense Benefit CurrentFederalTaxExpenseBenefit	1454049	USD
CY2020	us-gaap	Current State And Local Tax Expense Benefit CurrentStateAndLocalTaxExpenseBenefit	295074	USD
CY2019	us-gaap	Current State And Local Tax Expense Benefit CurrentStateAndLocalTaxExpenseBenefit	145412	USD
CY2018	us-gaap	Current State And Local Tax Expense Benefit CurrentStateAndLocalTaxExpenseBenefit	202292	USD
CY2020	us-gaap	Current Income Tax Expense Benefit CurrentIncomeTaxExpenseBenefit	1958957	USD
CY2019	us-gaap	Current Income Tax Expense Benefit CurrentIncomeTaxExpenseBenefit	1583007	USD
CY2018	us-gaap	Current Income Tax Expense Benefit CurrentIncomeTaxExpenseBenefit	1656341	USD
CY2020	us-gaap	Deferred Federal Income Tax Expense Benefit DeferredFederalIncomeTaxExpenseBenefit	-361167	USD
CY2019	us-gaap	Deferred Federal Income Tax Expense Benefit DeferredFederalIncomeTaxExpenseBenefit	105960	USD
CY2018	us-gaap	Deferred Federal Income Tax Expense Benefit DeferredFederalIncomeTaxExpenseBenefit	-79034	USD
CY2020	us-gaap	Deferred State And Local Income Tax Expense Benefit DeferredStateAndLocalIncomeTaxExpenseBenefit	-20833	USD
CY2019	us-gaap	Deferred State And Local Income Tax Expense Benefit DeferredStateAndLocalIncomeTaxExpenseBenefit	-9417	USD
CY2018	us-gaap	Deferred State And Local Income Tax Expense Benefit DeferredStateAndLocalIncomeTaxExpenseBenefit	-7781	USD
CY2020	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	-382000	USD
CY2019	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	96543	USD
CY2018	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	-86815	USD
CY2020	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	1576957	USD
CY2019	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	1679550	USD
CY2018	us-gaap	Tax Cuts And Jobs Act Of2017 Change In Tax Rate Deferred Tax Asset Income Tax Expense TaxCutsAndJobsActOf2017ChangeInTaxRateDeferredTaxAssetIncomeTaxExpense	1569526	USD
CY2020	us-gaap	Income Tax Reconciliation Income Tax Expense Benefit At Federal Statutory Income Tax Rate IncomeTaxReconciliationIncomeTaxExpenseBenefitAtFederalStatutoryIncomeTaxRate	1811788	USD
CY2019	us-gaap	Income Tax Reconciliation Income Tax Expense Benefit At Federal Statutory Income Tax Rate IncomeTaxReconciliationIncomeTaxExpenseBenefitAtFederalStatutoryIncomeTaxRate	1989548	USD
CY2018	us-gaap	Income Tax Reconciliation Income Tax Expense Benefit At Federal Statutory Income Tax Rate IncomeTaxReconciliationIncomeTaxExpenseBenefitAtFederalStatutoryIncomeTaxRate	1843117	USD
CY2020	us-gaap	Income Tax Reconciliation State And Local Income Taxes IncomeTaxReconciliationStateAndLocalIncomeTaxes	81936	USD
CY2019	us-gaap	Income Tax Reconciliation State And Local Income Taxes IncomeTaxReconciliationStateAndLocalIncomeTaxes	100820	USD
CY2018	us-gaap	Income Tax Reconciliation State And Local Income Taxes IncomeTaxReconciliationStateAndLocalIncomeTaxes	157417	USD
CY2020	sfdl	Income Tax Reconciliation State And Local Income Taxes Write Down IncomeTaxReconciliationStateAndLocalIncomeTaxesWriteDown	-250044	USD
CY2019	sfdl	Income Tax Reconciliation State And Local Income Taxes Write Down IncomeTaxReconciliationStateAndLocalIncomeTaxesWriteDown	-291768	USD
CY2018	sfdl	Income Tax Reconciliation State And Local Income Taxes Write Down IncomeTaxReconciliationStateAndLocalIncomeTaxesWriteDown	-338497	USD
CY2020	us-gaap	Income Tax Reconciliation Nondeductible Expense Life Insurance IncomeTaxReconciliationNondeductibleExpenseLifeInsurance	-120383	USD
CY2019	us-gaap	Income Tax Reconciliation Nondeductible Expense Life Insurance IncomeTaxReconciliationNondeductibleExpenseLifeInsurance	-142508	USD
CY2018	us-gaap	Income Tax Reconciliation Nondeductible Expense Life Insurance IncomeTaxReconciliationNondeductibleExpenseLifeInsurance	-113400	USD
CY2020	us-gaap	Income Tax Reconciliation Change In Deferred Tax Assets Valuation Allowance IncomeTaxReconciliationChangeInDeferredTaxAssetsValuationAllowance	53660	USD
CY2019	us-gaap	Income Tax Reconciliation Change In Deferred Tax Assets Valuation Allowance IncomeTaxReconciliationChangeInDeferredTaxAssetsValuationAllowance	23458	USD
CY2018	us-gaap	Income Tax Reconciliation Change In Deferred Tax Assets Valuation Allowance IncomeTaxReconciliationChangeInDeferredTaxAssetsValuationAllowance	20889	USD
CY2020	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	1576957	USD
CY2019	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	1679550	USD
CY2018	us-gaap	Tax Cuts And Jobs Act Of2017 Change In Tax Rate Deferred Tax Asset Income Tax Expense TaxCutsAndJobsActOf2017ChangeInTaxRateDeferredTaxAssetIncomeTaxExpense	1569526	USD
CY2020Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Compensation And Benefits DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefits	670582	USD
CY2019Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Compensation And Benefits DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefits	587322	USD
CY2020Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Reserves And Accruals Provision For Loan Losses DeferredTaxAssetsTaxDeferredExpenseReservesAndAccrualsProvisionForLoanLosses	2781850	USD
CY2019Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Reserves And Accruals Provision For Loan Losses DeferredTaxAssetsTaxDeferredExpenseReservesAndAccrualsProvisionForLoanLosses	2000131	USD
CY2020Q4	sfdl	Deferred Tax Assets Other Real Estate Owned DeferredTaxAssetsOtherRealEstateOwned	3248	USD
CY2019Q4	sfdl	Deferred Tax Assets Other Real Estate Owned DeferredTaxAssetsOtherRealEstateOwned	0	USD
CY2020Q4	sfdl	Deferred Tax Assets Tax Deferred Expense Financial Reporting Fees DeferredTaxAssetsTaxDeferredExpenseFinancialReportingFees	74743	USD
CY2019Q4	sfdl	Deferred Tax Assets Tax Deferred Expense Financial Reporting Fees DeferredTaxAssetsTaxDeferredExpenseFinancialReportingFees	76262	USD
CY2020Q4	us-gaap	Deferred Tax Assets Operating Loss Carryforwards DeferredTaxAssetsOperatingLossCarryforwards	410419	USD
CY2019Q4	us-gaap	Deferred Tax Assets Operating Loss Carryforwards DeferredTaxAssetsOperatingLossCarryforwards	356759	USD
CY2020Q4	us-gaap	Deferred Tax Assets Other DeferredTaxAssetsOther	105993	USD
CY2019Q4	us-gaap	Deferred Tax Assets Other DeferredTaxAssetsOther	126492	USD
CY2020Q4	us-gaap	Deferred Tax Assets Gross DeferredTaxAssetsGross	4046835	USD
CY2019Q4	us-gaap	Deferred Tax Assets Gross DeferredTaxAssetsGross	3146966	USD
CY2020Q4	us-gaap	Deferred Tax Assets Valuation Allowance DeferredTaxAssetsValuationAllowance	410419	USD
CY2019Q4	us-gaap	Deferred Tax Assets Valuation Allowance DeferredTaxAssetsValuationAllowance	356759	USD
CY2020Q4	us-gaap	Deferred Tax Assets Net DeferredTaxAssetsNet	3636416	USD
CY2019Q4	us-gaap	Deferred Tax Assets Net DeferredTaxAssetsNet	2790207	USD
CY2020Q4	us-gaap	Deferred Tax Liabilities Investments DeferredTaxLiabilitiesInvestments	72196	USD
CY2019Q4	us-gaap	Deferred Tax Liabilities Investments DeferredTaxLiabilitiesInvestments	72208	USD
CY2020Q4	us-gaap	Deferred Tax Liabilities Property Plant And Equipment DeferredTaxLiabilitiesPropertyPlantAndEquipment	1040831	USD
CY2019Q4	us-gaap	Deferred Tax Liabilities Property Plant And Equipment DeferredTaxLiabilitiesPropertyPlantAndEquipment	585520	USD
CY2020Q4	us-gaap	Deferred Tax Liabilities Other DeferredTaxLiabilitiesOther	43943	USD
CY2019Q4	us-gaap	Deferred Tax Liabilities Other DeferredTaxLiabilitiesOther	35033	USD
CY2020Q4	us-gaap	Deferred Tax Liabilities Unrealized Gains On Trading Securities DeferredTaxLiabilitiesUnrealizedGainsOnTradingSecurities	4037110	USD
CY2019Q4	us-gaap	Deferred Tax Liabilities Unrealized Gains On Trading Securities DeferredTaxLiabilitiesUnrealizedGainsOnTradingSecurities	1473077	USD
CY2020Q4	us-gaap	Deferred Income Tax Liabilities DeferredIncomeTaxLiabilities	5194080	USD
CY2019Q4	us-gaap	Deferred Income Tax Liabilities DeferredIncomeTaxLiabilities	2165838	USD
CY2020Q4	us-gaap	Deferred Tax Assets Liabilities Net DeferredTaxAssetsLiabilitiesNet	-1557664	USD
CY2019Q4	us-gaap	Deferred Tax Assets Liabilities Net DeferredTaxAssetsLiabilitiesNet	624369	USD
CY2020	us-gaap	Valuation Allowance Deferred Tax Asset Change In Amount ValuationAllowanceDeferredTaxAssetChangeInAmount	54000	USD
CY2020Q4	us-gaap	Bad Debt Reserve For Tax Purposes Of Qualified Lender BadDebtReserveForTaxPurposesOfQualifiedLender	2100000	USD
CY2020	sfdl	Defined Contribution Plan Requisite Service Period DefinedContributionPlanRequisiteServicePeriod	P6M
CY2020	us-gaap	Defined Contribution Plan Employer Discretionary Contribution Amount DefinedContributionPlanEmployerDiscretionaryContributionAmount	320000	USD
CY2019	us-gaap	Defined Contribution Plan Employer Discretionary Contribution Amount DefinedContributionPlanEmployerDiscretionaryContributionAmount	273000	USD
CY2018	us-gaap	Defined Contribution Plan Employer Discretionary Contribution Amount DefinedContributionPlanEmployerDiscretionaryContributionAmount	263000	USD
CY2020	sfdl	Maximum Days Earned For Bonus MaximumDaysEarnedForBonus	P7DT12H
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CY2020Q4	us-gaap	Employee Service Share Based Compensation Nonvested Awards Total Compensation Cost Not Yet Recognized Stock Options EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedStockOptions	0	USD
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CY2019Q4	us-gaap	Life Insurance Corporate Or Bank Owned Amount LifeInsuranceCorporateOrBankOwnedAmount	21500000	USD
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CY2019	us-gaap	Life Insurance Corporate Or Bank Owned Change In Value LifeInsuranceCorporateOrBankOwnedChangeInValue	540000	USD
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CY2020	us-gaap	Loans And Leases Receivable Commitments To Purchase Or Sell LoansAndLeasesReceivableCommitmentsToPurchaseOrSell	5700000	USD
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CY2020Q4	us-gaap	Loans Receivable Fair Value Disclosure LoansReceivableFairValueDisclosure	481450000	USD
CY2020Q4	us-gaap	Investment In Federal Home Loan Bank Stock Fair Value Disclosure InvestmentInFederalHomeLoanBankStockFairValueDisclosure	2354000	USD
CY2020	us-gaap	Cash Dividends Paid To Parent Company CashDividendsPaidToParentCompany	0	USD
CY2019	us-gaap	Cash Dividends Paid To Parent Company CashDividendsPaidToParentCompany	6400000	USD
CY2018	us-gaap	Cash Dividends Paid To Parent Company CashDividendsPaidToParentCompany	6400000	USD
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CY2020	sfdl	Loans And Leases Receivable Valuation Period For New Appraisal LoansAndLeasesReceivableValuationPeriodForNewAppraisal	P24M
CY2020Q4	us-gaap	Impaired Financing Receivable Recorded Investment ImpairedFinancingReceivableRecordedInvestment	2200000	USD
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CY2020Q4	us-gaap	Advances From Federal Home Loan Banks AdvancesFromFederalHomeLoanBanks	35000000	USD
CY2020Q4	us-gaap	Federal Home Loan Bank Borrowings Fair Value Disclosure FederalHomeLoanBankBorrowingsFairValueDisclosure	35200000	USD
CY2020Q4	us-gaap	Fair Value Liabilities Measured On Recurring Basis Obligations FairValueLiabilitiesMeasuredOnRecurringBasisObligations	13117000	USD
CY2020Q4	us-gaap	Junior Subordinated Notes JuniorSubordinatedNotes	5155000	USD
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CY2020	us-gaap	Impaired Financing Receivable Average Recorded Investment ImpairedFinancingReceivableAverageRecordedInvestment	3900000	USD
CY2019	us-gaap	Impaired Financing Receivable Average Recorded Investment ImpairedFinancingReceivableAverageRecordedInvestment	6400000	USD
CY2020Q4	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliations Recurring Basis Liability Value FairValueMeasurementWithUnobservableInputsReconciliationsRecurringBasisLiabilityValue	0	USD
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CY2020Q4	us-gaap	Cash And Cash Equivalents Fair Value Disclosure CashAndCashEquivalentsFairValueDisclosure	18025000	USD
CY2020Q4	sfdl	Certificates Of Deposits With Other Banks Fair Value Disclosure CertificatesOfDepositsWithOtherBanksFairValueDisclosure	350000	USD
CY2020Q4	sfdl	Investment And Mortgage Backed Securities Fair Value Disclosure InvestmentAndMortgageBackedSecuritiesFairValueDisclosure	608530000	USD
CY2020Q4	us-gaap	Fair Value Liabilities Measured On Recurring Basis Subordinated Debt Obligations FairValueLiabilitiesMeasuredOnRecurringBasisSubordinatedDebtObligations	5155000	USD
CY2019Q4	us-gaap	Cash And Cash Equivalents Fair Value Disclosure CashAndCashEquivalentsFairValueDisclosure	12536000	USD
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CY2019Q4	sfdl	Investment And Mortgage Backed Securities Fair Value Disclosure InvestmentAndMortgageBackedSecuritiesFairValueDisclosure	434451000	USD
CY2019Q4	us-gaap	Loans Receivable Fair Value Disclosure LoansReceivableFairValueDisclosure	450796000	USD
CY2019Q4	sfdl	Checking Savings And Money Market Accounts Fair Value Disclosure CheckingSavingsAndMoneyMarketAccountsFairValueDisclosure	541954000	USD
CY2019Q4	sfdl	Certificate Accounts Fair Value Disclosure CertificateAccountsFairValueDisclosure	229363000	USD
CY2019Q4	us-gaap	Advances From Federal Home Loan Banks AdvancesFromFederalHomeLoanBanks	38138000	USD
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CY2019Q4	us-gaap	Fair Value Liabilities Measured On Recurring Basis Subordinated Debt Obligations FairValueLiabilitiesMeasuredOnRecurringBasisSubordinatedDebtObligations	5155000	USD
CY2019Q4	us-gaap	Senior Notes SeniorNotes	6044000	USD
CY2019Q4	us-gaap	Convertible Debt Fair Value Disclosures ConvertibleDebtFairValueDisclosures	6044000	USD
CY2020Q4	us-gaap	Fair Value Disclosure Offbalance Sheet Risks Amount Liability FairValueDisclosureOffbalanceSheetRisksAmountLiability	143600000	USD
CY2020Q1	us-gaap	Interest And Dividend Income Operating InterestAndDividendIncomeOperating	9095000	USD
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CY2020Q4	us-gaap	Interest Income Expense Net InterestIncomeExpenseNet	8389000	USD
CY2020Q1	us-gaap	Provision For Loan And Lease Losses ProvisionForLoanAndLeaseLosses	700000	USD
CY2020Q2	us-gaap	Provision For Loan And Lease Losses ProvisionForLoanAndLeaseLosses	700000	USD
CY2020Q3	us-gaap	Provision For Loan And Lease Losses ProvisionForLoanAndLeaseLosses	2200000	USD
CY2020Q4	us-gaap	Provision For Loan And Lease Losses ProvisionForLoanAndLeaseLosses	0	USD
CY2020Q1	us-gaap	Interest Income Expense After Provision For Loan Loss InterestIncomeExpenseAfterProvisionForLoanLoss	6176000	USD
CY2020Q2	us-gaap	Interest Income Expense After Provision For Loan Loss InterestIncomeExpenseAfterProvisionForLoanLoss	6642000	USD
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CY2020Q4	us-gaap	Interest Income Expense After Provision For Loan Loss InterestIncomeExpenseAfterProvisionForLoanLoss	8389000	USD
CY2020Q1	us-gaap	Noninterest Income NoninterestIncome	2796000	USD
CY2020Q2	us-gaap	Noninterest Income NoninterestIncome	2806000	USD
CY2020Q3	us-gaap	Noninterest Income NoninterestIncome	2988000	USD
CY2020Q4	us-gaap	Noninterest Income NoninterestIncome	2831000	USD
CY2020Q1	us-gaap	General And Administrative Expense GeneralAndAdministrativeExpense	7644000	USD
CY2020Q2	us-gaap	General And Administrative Expense GeneralAndAdministrativeExpense	6991000	USD
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CY2020Q1	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	264000	USD
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CY2020Q3	us-gaap	Net Income Loss NetIncomeLoss	905000	USD
CY2020Q3	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.28
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CY2020Q1	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.34
CY2019Q3	us-gaap	Interest Expense InterestExpense	2291000	USD
CY2019Q4	us-gaap	Noninterest Income NoninterestIncome	2000000	USD
CY2020Q3	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	3252884	shares
CY2020Q4	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	3252884	shares
CY2019Q1	us-gaap	Interest And Dividend Income Operating InterestAndDividendIncomeOperating	9031000	USD
CY2020Q2	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.62
CY2020Q3	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.28
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CY2020Q1	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	3092455	shares
CY2020Q2	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	3252884	shares
CY2020Q3	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	3252884	shares
CY2020Q4	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	3252884	shares
CY2020Q1	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	3092455	shares
CY2020Q2	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	3252884	shares
CY2019Q2	us-gaap	Interest And Dividend Income Operating InterestAndDividendIncomeOperating	9128000	USD
CY2019Q3	us-gaap	Interest And Dividend Income Operating InterestAndDividendIncomeOperating	9641000	USD
CY2019Q4	us-gaap	Interest And Dividend Income Operating InterestAndDividendIncomeOperating	9134000	USD
CY2019Q1	us-gaap	Interest Expense InterestExpense	1774000	USD
CY2019Q2	us-gaap	Interest Expense InterestExpense	2009000	USD
CY2019Q3	us-gaap	Interest Income Expense After Provision For Loan Loss InterestIncomeExpenseAfterProvisionForLoanLoss	7275000	USD
CY2019Q4	us-gaap	Interest Expense InterestExpense	2237000	USD
CY2019Q1	us-gaap	Interest Income Expense Net InterestIncomeExpenseNet	7257000	USD
CY2019Q2	us-gaap	Interest Income Expense Net InterestIncomeExpenseNet	7119000	USD
CY2019Q3	us-gaap	Interest Income Expense Net InterestIncomeExpenseNet	7350000	USD
CY2019Q4	us-gaap	Interest Income Expense Net InterestIncomeExpenseNet	6897000	USD
CY2019Q1	us-gaap	Provision For Loan And Lease Losses ProvisionForLoanAndLeaseLosses	100000	USD
CY2019Q2	us-gaap	Provision For Loan And Lease Losses ProvisionForLoanAndLeaseLosses	0	USD
CY2019Q3	us-gaap	Provision For Loan And Lease Losses ProvisionForLoanAndLeaseLosses	75000	USD
CY2019Q4	us-gaap	Provision For Loan And Lease Losses ProvisionForLoanAndLeaseLosses	200000	USD
CY2019Q1	us-gaap	Interest Income Expense After Provision For Loan Loss InterestIncomeExpenseAfterProvisionForLoanLoss	7157000	USD
CY2019Q2	us-gaap	Interest Income Expense After Provision For Loan Loss InterestIncomeExpenseAfterProvisionForLoanLoss	7119000	USD
CY2019Q4	us-gaap	Interest Income Expense After Provision For Loan Loss InterestIncomeExpenseAfterProvisionForLoanLoss	6697000	USD
CY2019Q1	us-gaap	Noninterest Income NoninterestIncome	2196000	USD
CY2019Q2	us-gaap	Noninterest Income NoninterestIncome	2492000	USD
CY2019Q3	us-gaap	Noninterest Income NoninterestIncome	2408000	USD
CY2019Q3	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	475000	USD
CY2019Q4	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	199000	USD
CY2019Q1	us-gaap	Net Income Loss NetIncomeLoss	2089000	USD
CY2019Q1	us-gaap	General And Administrative Expense GeneralAndAdministrativeExpense	6744000	USD
CY2019Q2	us-gaap	General And Administrative Expense GeneralAndAdministrativeExpense	7241000	USD
CY2019Q3	us-gaap	General And Administrative Expense GeneralAndAdministrativeExpense	6989000	USD
CY2019Q4	us-gaap	General And Administrative Expense GeneralAndAdministrativeExpense	6896000	USD
CY2019Q1	us-gaap	Income Loss From Continuing Operations Before Income Taxes Domestic IncomeLossFromContinuingOperationsBeforeIncomeTaxesDomestic	2609000	USD
CY2019Q2	us-gaap	Income Loss From Continuing Operations Before Income Taxes Domestic IncomeLossFromContinuingOperationsBeforeIncomeTaxesDomestic	2370000	USD
CY2019Q3	us-gaap	Income Loss From Continuing Operations Before Income Taxes Domestic IncomeLossFromContinuingOperationsBeforeIncomeTaxesDomestic	2694000	USD
CY2019Q4	us-gaap	Income Loss From Continuing Operations Before Income Taxes Domestic IncomeLossFromContinuingOperationsBeforeIncomeTaxesDomestic	1801000	USD
CY2019Q1	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	520000	USD
CY2019Q2	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	486000	USD
CY2019Q2	us-gaap	Net Income Loss NetIncomeLoss	1884000	USD
CY2019Q3	us-gaap	Net Income Loss NetIncomeLoss	2219000	USD
CY2019Q4	us-gaap	Net Income Loss NetIncomeLoss	1602000	USD
CY2019Q1	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	3256715	shares
CY2019Q4	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	2956600	shares
CY2019Q1	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.71
CY2019Q2	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.64
CY2019Q3	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.75
CY2019Q4	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.54
CY2019Q1	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.67
CY2019Q2	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.61
CY2019Q3	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.71
CY2019Q4	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.51
CY2019Q1	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	2954515	shares
CY2019Q2	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	2955650	shares
CY2019Q3	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	2956156	shares
CY2019Q2	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	3257850	shares
CY2019Q3	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	3258356	shares
CY2019Q4	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	3258800	shares

Files In Submission

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$SFDL
SECURITY FEDERAL CORP Stock $sfdl

2020 Q4 Form 10-K Financial Statement

#000093905721000114 Filed on March 29, 2021

Income Statement

Balance Sheet

Cashflow Statement

Facts In Submission

Files In Submission

$SFDL SECURITY FEDERAL CORP Stock $sfdl

2020 Q4 Form 10-K Financial Statement

#000093905721000114 Filed on March 29, 2021

Income Statement

Balance Sheet

Cashflow Statement

Facts In Submission

Files In Submission

$SFDL
SECURITY FEDERAL CORP Stock $sfdl