No definition available.

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Namespace Prefix:	sbfc_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount before allowance of loans and leases held in portfolio. Excludes deferred income.

+ References

No definition available.

+ Details

Name:	sbfc_LoansReceivableGross
Namespace Prefix:	sbfc_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- References

No definition available.

+ Details

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

- Definition

The valuation allowance for financing receivables that are expected to be uncollectible that were collectively evaluated for impairment.

+ References

+ Details

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

- Definition

Amount of valuation allowance for financing receivables that are expected to be uncollectible that were individually evaluated for impairment.

+ References

+ Details

Name:	us-gaap_FinancingReceivableAllowanceForCreditLossesIndividuallyEvaluatedForImpairment1
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The balance of financing receivables that were collectively evaluated for impairment.

+ References

+ Details

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

- Definition

The balance of financing receivables that were individually evaluated for impairment.

+ References

+ Details

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

- Definition

Amount of allowance to cover probable credit losses on loans and leases. Includes carryover of or adjustments to the allowance for loan losses in connection with business combinations. Excludes allowance for loans and leases covered under loss sharing agreements.

+ 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 (g)
-URI http://asc.fasb.org/extlink&oid=66008989&loc=SL6953423-111524

Reference 2: 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=66008989&loc=SL6953423-111524

Reference 3: 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 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section S99
-Paragraph 4
-Subparagraph (SAB Topic 6.L.1)
-URI http://asc.fasb.org/extlink&oid=27010918&loc=d3e74567-122707

Reference 5: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 30
-Section 50
-Paragraph 2
-Subparagraph (b)(1)(ii)
-URI http://asc.fasb.org/extlink&oid=6379141&loc=d3e15032-111544

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

- Details

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Namespace Prefix:
Data Type:	na
Balance Type:
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- Details

Name:	us-gaap_FinancingReceivablePortfolioSegmentAxis=us-gaap_CommercialRealEstatePortfolioSegmentMember
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- Details

Name:	us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis=sbfc_CommercialRealEstateOwnerOccupiedMember
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- Details

Name:	us-gaap_FinancingReceivablePortfolioSegmentAxis=sbfc_ResidentialRealEstatePortfolioSegmentMember
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Data Type:	na
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- Details

Name:	us-gaap_FinancingReceivablePortfolioSegmentAxis=sbfc_AcquisitionDevelopmentAndConstructionRealEstatePortfolioMember
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Loans - Allowance for loan losses and recorded investment in loans by portfolio segment and based on impairment method (Details 2) - USD ($) $ in Thousands	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2014
Allowance for loan losses:
Individually evaluated for impairment	$ 199
Collectively evaluated for impairment	21,202		21,367
Allowance for loan losses	21,401	$ 21,548	21,367	$ 23,372	$ 25,391	$ 25,506
Loans:
Individually evaluated for impairment	11,287		15,472
Collectively evaluated for impairment	1,015,796		993,843
Loans	1,027,083		1,009,315
Commercial, Financial, and Agricultural
Allowance for loan losses:
Individually evaluated for impairment	199
Collectively evaluated for impairment	5,390		4,908
Allowance for loan losses	5,589	4,998	4,908	4,427	5,295	5,407
Loans:
Individually evaluated for impairment	751		991
Collectively evaluated for impairment	225,497		209,721
Loans	226,248		210,712
CRE
Loans:
Loans	370,501		366,566
CRE \| Owner Occupied
Allowance for loan losses:
Individually evaluated for impairment
Collectively evaluated for impairment	4,431		4,667
Allowance for loan losses	4,431	4,605	4,667	5,441	5,373	4,805
Loans:
Individually evaluated for impairment	3,680		3,771
Collectively evaluated for impairment	224,361		225,592
Loans	228,041		229,363
CRE \| Non Owner occupied
Allowance for loan losses:
Individually evaluated for impairment
Collectively evaluated for impairment	2,617		2,709
Allowance for loan losses	2,617	2,836	2,709	3,841	3,838	3,817
Loans:
Individually evaluated for impairment	3,301		6,244
Collectively evaluated for impairment	139,159		130,959
Loans	142,460		137,203
Residential Real Estate
Allowance for loan losses:
Individually evaluated for impairment
Collectively evaluated for impairment	5,107		5,027
Allowance for loan losses	5,107	5,024	5,027	6,336	6,355	6,591
Loans:
Individually evaluated for impairment	2,607		1,998
Collectively evaluated for impairment	243,002		227,163
Loans	245,609		229,161
ADC
Loans:
Loans	164,893		184,292
ADC \| CSRA
Allowance for loan losses:
Individually evaluated for impairment
Collectively evaluated for impairment	2,050		2,469
Allowance for loan losses	2,050	2,553	2,469	1,805	1,631	1,943
Loans:
Individually evaluated for impairment	948		2,468
Collectively evaluated for impairment	119,205		138,649
Loans	120,153		141,117
ADC \| Other
Allowance for loan losses:
Individually evaluated for impairment
Collectively evaluated for impairment	940		914
Allowance for loan losses	940	828	914	921	2,197	2,320
Loans:
Individually evaluated for impairment
Collectively evaluated for impairment	44,740		43,175
Loans	44,740		43,175
Consumer
Allowance for loan losses:
Individually evaluated for impairment
Collectively evaluated for impairment	667		673
Allowance for loan losses	667	$ 704	673	$ 601	$ 702	$ 623
Loans:
Individually evaluated for impairment
Collectively evaluated for impairment	19,832		18,584
Loans	$ 19,832		$ 18,584