Bank Owned Life Insurance (Details) (USD $)	9 Months Ended	12 Months Ended
Dec. 31, 2012	Dec. 31, 2014	Dec. 31, 2013
Investments, All Other Investments [Abstract]
Bank Owned Life Insurance		$ 11,150,045us-gaap_BankOwnedLifeInsurance	$ 11,474,305us-gaap_BankOwnedLifeInsurance
Life Insurance, Corporate or Bank Owned, Change in Value	315,000	300,000	339,000
Bank Owned Life Insurance Income	315,000us-gaap_BankOwnedLifeInsuranceIncome	554,364us-gaap_BankOwnedLifeInsuranceIncome	339,000us-gaap_BankOwnedLifeInsuranceIncome
BOLI death benefits		$ 254,000sfdl_BOLIdeathbenefits

BOLI death benefits

No definition available.

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- Definition

The carrying amount of a life insurance policy on an officer, executive or employee for which the reporting entity (a bank) is entitled to proceeds from the policy upon death of the insured or surrender of the insurance policy.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.9-03.10)

-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 10

-Article 9

+ Details

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- Definition

Earnings on or other increases in the value of the cash surrender value of bank owned life insurance policies.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 225

-Section S99

-Paragraph 1

-Subparagraph (SX 210.9-04.13)

-URI http://asc.fasb.org/extlink&oid=6879574&loc=d3e536633-122882

+ Details

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- Details

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- Definition

The change in cash surrender or contract value during the period which adjusted the amount of premiums paid in determining the expense or income recognized under the contract for the period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 325

-SubTopic 30

-Section 35

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6384439&loc=d3e42048-111605

+ Details

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