XML 70 R57.htm IDEA: XBRL DOCUMENT v3.10.0.1

Investment Securities (Details Textual) $ in Thousands	12 Months Ended
	Dec. 31, 2018 USD ($) Investments	Dec. 31, 2017 USD ($) Investments	Dec. 31, 2016 USD ($)
Investment Securities (Textual)
Gain on sale of investment securities	$ 7	$ 4	$ 431
Number of investments, Less than 12 months | Investments	8	25
Fair market value, less than 12 months	$ 11,700
Number of investments, 12 months or longer | Investments	53	28
Fair market value,12 months or longer	$ 46,500
Securities pledged as collateral for repurchase agreements from brokers		$ 7,700

X

- Definition

Investment securities.

+ References

No definition available.

+ Details

Name:	sfst_InvestmentSecuritiesTextualAbstract
Namespace Prefix:	sfst_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

X

- Definition

Investments with fair market value in continuous unrealized loss position for less than twelve months.

+ References

No definition available.

+ Details

Name:	sfst_InvestmentsWithFairMarketValueInContinuousUnrealizedLossPositionLessThanTwelveMonths
Namespace Prefix:	sfst_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

X

- Definition

Investments with fair market value In continuous unrealized loss position twelve months or longer.

+ References

No definition available.

+ Details

Name:	sfst_InvestmentsWithFairMarketValueInContinuousUnrealizedLossPositionTwelveMonthsOrLonger
Namespace Prefix:	sfst_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

X

- Definition

Number of investments in continuous unrealized loss position, less than twelve months.

+ References

No definition available.

+ Details

Name:	sfst_NumberOfInvestmentsInContinuousUnrealizedLossPositionLessThanTwelveMonths
Namespace Prefix:	sfst_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant

X

- Definition

Number of investments in continuous unrealized loss position twelve months or longer.

+ References

No definition available.

+ Details

Name:	sfst_NumberOfInvestmentsInContinuousUnrealizedLossPositionTwelveMonthsOrLonger
Namespace Prefix:	sfst_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant

X

- Definition

Amount of restricted investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 30
-Section 50
-Paragraph 1A
-Subparagraph (b)(1)(i)
-URI http://asc.fasb.org/extlink&oid=109249958&loc=SL6224234-111729

+ Details

Name:	us-gaap_DebtSecuritiesAvailableForSaleRestricted
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

X

- Definition

The difference between the carrying value and the sale price of an investment. A gain would be recognized when the sale price of the investment is greater than the carrying value of the investment. This element refers to the Gain included in earnings and not to the cash proceeds of the sale.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 220
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-04(3)(a))
-URI http://asc.fasb.org/extlink&oid=114873790&loc=SL114874131-224263

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3602-108585

Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 220
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-04(13))
-URI http://asc.fasb.org/extlink&oid=114873765&loc=SL114874048-224260

Reference 4: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03(b)(9)(a))
-URI http://asc.fasb.org/extlink&oid=115205541&loc=SL114868664-224227

Reference 5: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03(b)(7)(c))
-URI http://asc.fasb.org/extlink&oid=115205541&loc=SL114868664-224227

+ Details

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