Summary of Significant Accounting Policies - Concentrations of Credit Risk- (Details 2) - Loans - Concentrations of Credit Risk $ in Millions	Dec. 31, 2015 USD ($) item
Concentrations of Credit Risk
Concentration risk threshold, total risk-based capital threshold (as a percent)	25.00%
Concentration risk threshold, total risk-based capital threshold	$ 200.4
Number of credit concentrations for non-acquired credit impaired loans \| item	4
Lessors of residential and buildings
Concentrations of Credit Risk
Amount loaned	$ 237.1
Lessors of nonresidential buildings
Concentrations of Credit Risk
Amount loaned	540.7
Religious
Concentrations of Credit Risk
Amount loaned	238.4
Borrowers engaged in offices of physicians, dentists and other health practitioners
Concentrations of Credit Risk
Amount loaned	$ 235.8

- Definition

Represents the concentration amount, for the entity that discloses a concentration risk in relation to quantitative amount, which serves as a benchmark (or denominator) in the equation.

+ References

No definition available.

+ Details

Name:	ssb_ConcentrationRiskAmount
Namespace Prefix:	ssb_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Represents the number of credit concentrations meeting threshold for concentration of risk.

+ References

No definition available.

+ Details

Name:	ssb_ConcentrationRiskNumber
Namespace Prefix:	ssb_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant

- Definition

Represents the threshold amount for determining concentration of risk.

+ References

No definition available.

+ Details

Name:	ssb_ConcentrationRiskThresholdAmount
Namespace Prefix:	ssb_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Represents the threshold percentage for determining concentration of risk.

+ References

No definition available.

+ Details

Name:	ssb_ConcentrationRiskThresholdPercentage
Namespace Prefix:	ssb_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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

- Details

Name:	us-gaap_ConcentrationRiskByBenchmarkAxis=us-gaap_FinanceReceivablesMember
Namespace Prefix:
Data Type:	na
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- Details

Name:	us-gaap_ConcentrationRiskByTypeAxis=us-gaap_CreditConcentrationRiskMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_MajorCustomersAxis=ssb_LessorsOfResidentialBuildingsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_MajorCustomersAxis=ssb_LessorsOfNonresidentialBuildingsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_MajorCustomersAxis=ssb_ReligiousOrganizationsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_MajorCustomersAxis=ssb_BorrowersEngagedInOfficesOfPhysiciansDentistsAndOtherHealthPractitionersMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: