Summary of Significant Accounting Policies - Cash, TDRs - (Details)	12 Months Ended
Dec. 31, 2016
Cash and Cash Equivalents
Period for sale and purchase of federal funds	1 day
Troubled Debt Restructurings (TDRs)
Minimum reasonable period for sustained repayment performance by borrower for returning nonaccrual TDRs to accruing status	6 months

Represents the minimum reasonable period for a sustained repayment performance by the borrower for returning nonaccrual TDRs to accruing status.

No definition available.

Name:	ssb_TroubledDebtRestructuringMinimumReasonablePeriodOfSustainedRepaymentPerformanceForReturningNonaccrualTDRsToAccruingStatus
Namespace Prefix:	ssb_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration