Amount of uninsured deposits adjusted to exclude over assessment periods.

No definition available.

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

The total amount outstanding of the commitments to extend credit and standby letters of credit as of the reporting date.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount of additional expense for Federal Deposit Insurance Corporation (FDIC) special assessment.

+ References

No definition available.

+ Details

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Namespace Prefix:	ssb_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Amount of expense for Federal Deposit Insurance Corporation (FDIC) special assessment.

+ References

No definition available.

+ Details

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Namespace Prefix:	ssb_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

The amount of liability recorded for expected credit losses on unfunded commitments.

+ References

No definition available.

+ Details

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Namespace Prefix:	ssb_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Period for special assessment.

+ References

No definition available.

+ Details

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

- Definition

Percentage of base annual rate of uninsured deposits.

+ References

No definition available.

+ Details

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Namespace Prefix:	ssb_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Number of pending claims pertaining to a loss contingency.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 450
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 4
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147483076/450-20-50-4

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 450
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 9
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147483076/450-20-50-9

+ Details

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Period Type:	instant

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Commitments and Contingent Liabilities (Details) $ in Millions	3 Months Ended	6 Months Ended	12 Months Ended
	Mar. 31, 2024	Jun. 30, 2024 USD ($)	Dec. 31, 2023 USD ($)	Dec. 31, 2022 USD ($)	Jul. 30, 2024 case
Commitments to extend credit and standby letters of credit		$ 9,200.0
Liability recorded for expected credit losses on unfunded commitments		50.2
FDIC base annual rate	13.40%
Amount of uninsured deposits adjusted to exclude over assessment periods			$ 25.7	$ 5,000.0
Period for special assessment			2 years
FDIC special assessment additional expense		4.5
FDIC special assessment		$ 30.2
Subsequent event
Number of pending or threatened litigation \| case					3
Cases Pending In US District Court \| Florida \| Subsequent event
Number of pending or threatened litigation \| case					2
Cases Pending In US District Court \| Georgia \| Subsequent event
Number of pending or threatened litigation \| case					1