Loan Servicing, Mortgage Origination, and Loans Held for Sale - Mandatory cash forwards - (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2016	Dec. 31, 2015
Mortgage loan securitizations, mandatory cash forwards, and whole loan sales
Mandatory cash forwards and whole loan sales	$ 745.7	$ 843.0
Mandatory cash forwards and whole loan sales, without servicing rights	$ 605.6	$ 631.1
Percentage of loan securitizations and loan sales	81.20%	74.90%
Residential mortgage loans to be sold in secondary market
Mortgage loan securitizations, mandatory cash forwards, and whole loan sales
Residential mortgage loans held for sale	$ 50.6	$ 41.6
Loans Held-for-sale, Mortgages	$ 50.6	$ 41.6
Residential mortgage loans awaiting sale in secondary market \| Minimum
Mortgage loan securitizations, mandatory cash forwards, and whole loan sales
Loans held for sale, settlement period	15 days
Residential mortgage loans awaiting sale in secondary market \| Maximum
Mortgage loan securitizations, mandatory cash forwards, and whole loan sales
Loans held for sale, settlement period	45 days

Represent the settlement period of loan held for sale.

No definition available.

Name:	ssb_LoansHeldForSaleSettlementPeriod
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- Definition

Represents the amount of mandatory cash forwards and whole loan sales including all securities sold with servicing rights or not.

+ References

No definition available.

+ Details

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Namespace Prefix:	ssb_
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Period Type:	duration

- Definition

Represents the mandatory cash forwards and whole loan sales, securities sold with the servicing rights being retained by the company.

+ References

No definition available.

+ Details

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Balance Type:	credit
Period Type:	duration

- References

No definition available.

+ Details

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- Definition

Represents the percentage of mortgage loan securitized and sold during the period with servicing rights retained by the company.

+ References

No definition available.

+ Details

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Data Type:	num:percentItemType
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- Definition

Amount, after allowance for bad debt, of mortgage loan receivables held-for-sale that are not part of a disposal group. Excludes loans and leases covered under loss sharing agreements and loans classified as debt securities.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=65884687&loc=d3e4428-111522

+ Details

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- Details

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- Details

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- Details

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- Details

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