Carrying Amounts and Fair Value of Financial Instruments (Narrative) (Details) (USD $)	3 Months Ended
Mar. 31, 2015 investment	Dec. 31, 2014
Fair Value Disclosures [Abstract]
Number of equity investments	2sfdl_EquityInvestmentNumber
Investor funding period	30 days
Review period to request a new third party appraisal	24 months
Impaired financing receivable, recorded investment	$ 15,698,201	$ 20,247,955
Fair value disclosure, off-balance sheet risks, amount, liability	$ 46,100,000

Equity Investment, Number

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- Definition

Investor Funding, Period

+ References

No definition available.

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- Definition

Loans and Leases Receivable, Valuation Period for New Appraisal

+ References

No definition available.

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- Definition

The fair value of financial liabilities, which are not recognized in the financial statements (off-balance sheet) because they fail to meet some other criterion for recognition.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 825

-SubTopic 10

-Section 50

-Paragraph 10

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=49121117&loc=d3e13433-108611

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- Definition

Amount of investment of impaired financing receivables with related allowance for credit losses and without a related allowance for credit losses.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 14A

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=49124121&loc=SL6953550-111524

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