XML 106 R93.htm IDEA: XBRL DOCUMENT v3.24.0.1

FAIR VALUE MEASUREMENT - Fair Value Measurements, Narrative (Details)	12 Months Ended
	Dec. 31, 2023 source
Available-for-sale Securities
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Number of additional third party sources used to validate prices	2
Derivative [Member]
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Number of additional third party sources used to validate prices	2

X

- Definition

Number of Third Party Sources Used to Validate Prices

+ References

No definition available.

+ Details

Name:	sbsi_NumberofThirdPartySourcesUsedtoValidatePrices
Namespace Prefix:	sbsi_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

X

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

X

- Details

Name:	us-gaap_FinancialInstrumentAxis=us-gaap_AvailableforsaleSecuritiesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_FinancialInstrumentAxis=us-gaap_DerivativeMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: