Allowance for loan and lease losses write offs net of recoveries.

No definition available.

Name:	sfst_AllowanceForLoanAndLeaseLossesWriteOffsNetOfRecoveries
Namespace Prefix:	sfst_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Allowance for loan losses as a percentage of gross loans.

+ References

No definition available.

+ Details

Name:	sfst_AllowanceForLoanLossesAsPercentageOfGrossLoans
Namespace Prefix:	sfst_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Allowance for credit losses as a percentage of nonperforming loans.

+ References

No definition available.

+ Details

Name:	sfst_AllowanceForLoanLossesAsPercentageOfNonperformingLoans
Namespace Prefix:	sfst_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Net loan charge offs annualized as a percentage of average total loans.

+ References

No definition available.

+ Details

Name:	sfst_NetLoanChargeOffsAnnualizedAsPercentageOfAverageLoans
Namespace Prefix:	sfst_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount of loans and leases that have been written off from both loan receivables and allowance reserve for credit loss.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 15

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=28368275&loc=d3e5212-111524

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.9-03.7(d))

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

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 7

-Subparagraph d

-Article 9

+ Details

Name:	us-gaap_AllowanceForLoanAndLeaseLossesWriteOffs
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

A valuation allowance for financing receivables that are expected to be uncollectible.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 11B

-Subparagraph (c)(1)

-URI http://asc.fasb.org/extlink&oid=28368275&loc=SL6953423-111524

+ Details

Name:	us-gaap_FinancingReceivableAllowanceForCreditLosses
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Details

Name:	us-gaap_FinancingReceivableAllowanceForCreditLossesRollForward
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount of expense related loan transactions, lease transactions, credit loss from transactions other than loan and lease transactions, and other loss based on assessment of uncollectability from the counterparty to reduce the account to their net realizable value.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 28

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3602-108585

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 04

-Paragraph 11

-Article 9

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 11B

-Subparagraph (c)(2)

-URI http://asc.fasb.org/extlink&oid=28368275&loc=SL6953423-111524

Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 225

-Section S99

-Paragraph 1

-Subparagraph (SX 210.9-04.11)

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

+ Details

Name:	us-gaap_ProvisionForLoanLeaseAndOtherLosses
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Total of recoveries of amounts due the Entity that had previously been written off as uncollectible using allowances (the valuation accounts that are netted against the cost of an asset to value it at its carrying value) and total of reestablishments of reserves (liabilities established to represent expected future costs) that had previously been utilized.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 235

-SubTopic 10

-Section S99

-Paragraph 4

-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e24092-122690

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 09

-Article 12

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

Loans and Allowance for Loan Losses (Details 7) (USD $) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended		12 Months Ended
	Jun. 30, 2013	Jun. 30, 2012	Jun. 30, 2013	Jun. 30, 2012	Dec. 31, 2012
Summary of activity related to our allowance for loan losses
Balance, beginning of period			$ 9,091	$ 8,925	$ 8,925
Provision for loan losses	750	1,275	1,875	2,475	4,550
Total loan charge-offs			(1,504)	(2,287)	(4,505)
Loan recoveries			99	18	121
Net loan charge-offs			(1,405)	(2,269)	(4,384)
Balance, end of period	9,561	9,131	9,561	9,131	9,091
Net charge-offs to average loans (annualized)			0.43%	0.75%
Allowance for loan losses to gross loans			1.39%	1.48%
Allowance for loan losses to nonperforming loans			172.48%	88.07%
Commercial [Member]
Summary of activity related to our allowance for loan losses
Balance, beginning of period			7,981
Total loan charge-offs			(1,420)	(2,105)
Loan recoveries			92	13
Balance, end of period	7,985		7,985
Commercial [Member] \| Owner occupied RE [Member]
Summary of activity related to our allowance for loan losses
Total loan charge-offs			(386)	(892)
Loan recoveries			2	4
Commercial [Member] \| Non-owner occupied RE [Member]
Summary of activity related to our allowance for loan losses
Total loan charge-offs			(172)	(232)
Loan recoveries
Commercial [Member] \| Construction [Member]
Summary of activity related to our allowance for loan losses
Total loan charge-offs
Loan recoveries				9
Commercial [Member] \| Business [Member]
Summary of activity related to our allowance for loan losses
Total loan charge-offs			(862)	(981)
Loan recoveries			90
Consumer [Member]
Summary of activity related to our allowance for loan losses
Balance, beginning of period			1,110
Total loan charge-offs			(84)	(182)
Loan recoveries			7	5
Balance, end of period	1,576		1,576
Consumer [Member] \| Real estate [Member]
Summary of activity related to our allowance for loan losses
Total loan charge-offs				(175)
Loan recoveries
Consumer [Member] \| Home equity [Member]
Summary of activity related to our allowance for loan losses
Total loan charge-offs			(38)	(7)
Loan recoveries			7
Consumer [Member] \| Construction [Member]
Summary of activity related to our allowance for loan losses
Total loan charge-offs
Loan recoveries
Consumer [Member] \| Other [Member]
Summary of activity related to our allowance for loan losses
Total loan charge-offs			(46)
Loan recoveries				$ 5