Deposits - Total deposits (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Deposits
Non-interest bearing checking	$ 11,333,881	$ 9,711,338
Interest-bearing checking	7,920,236	6,955,575
Savings	3,201,543	2,694,011
Money market	8,110,162	7,584,353
Time deposits	2,994,736	3,748,605
Total deposits	$ 33,560,558	$ 30,693,882

No definition available.

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- Definition

Represents the amount of other time deposits, not otherwise specified in the taxonomy, that cannot be withdrawn before a set date without penalty or for which notice of withdrawal is required.

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No definition available.

+ Details

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

- Definition

The aggregate of all deposit liabilities held by the entity, including foreign and domestic, interest and noninterest bearing; may include demand deposits, saving deposits, Negotiable Order of Withdrawal (NOW) and time deposits among others.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.12)
-URI http://asc.fasb.org/extlink&oid=120398452&loc=d3e534808-122878

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- Definition

Amount of deposits in accounts that offer many of the same services as checking accounts although transactions may be somewhat more limited, share some of the characteristics of a money market fund and are insured by the Federal government, also known as money market accounts.

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Period Type:	instant

- Definition

Amount of interest bearing deposits with no stated maturity, which may include passbook and statement savings accounts and money-market deposit accounts (MMDAs).

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- Definition

Amount of money in interest-bearing domestic accounts that entitle the depositor to withdraw funds at any time without prior notice, also known as demand deposits.

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+ Details

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- Definition

Amount of money in noninterest-bearing domestic accounts that entitle the depositor to withdraw funds at any time without prior notice, also known as demand deposits.

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+ Details

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