XML 79 R69.htm IDEA: XBRL DOCUMENT
v3.24.1.u1

Off-Balance-Sheet Arrangements, Commitments and Contingencies Narrative (Details) - USD ($) | 3 Months Ended |
--- | --- | ---
Mar. 31, 2024 | Mar. 31, 2023 | Dec. 31, 2023
Commitments and Contingencies Disclosure [Abstract] |  |  |
Operating lease right-of-use assets obtained in exchange for new operating lease liabilities | $ 372,000 | $ 192,000 |
Operating lease ROU assets | 14,876,000 |  | $ 14,837,000
Unsettled trades to purchase securities | 7,160,000 | 0 | 0
Unsettled trades to sell securities | 6,406,000 | $ 4,044,000 | 0
Unsettled Issuances of Brokered CDs | $ 0 |  | $ 0

X
- Definition Amount of brokered CDs sold that were not settled by the end of the period. The amount recorded is the selling price including any accrued interest. + References No definition available. + Details
Name: | sbsi_UnsettledIssuancesofBrokeredCDs
Namespace Prefix: | sbsi_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Amount of securities purchased that were not settled by the end of the period. The amount recorded is the purchase price including any accrued interest. This asset is collected upon delivery of the securities. + References No definition available. + Details
Name: | sbsi_UnsettledTradesToPurchaseSecuritiesLiability
Namespace Prefix: | sbsi_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Amount of securities sold that were not settled by the end of the period. The amount recorded is the selling price including any accrued interest. This asset is collected upon delivery of the securities. + References No definition available. + Details
Name: | sbsi_UnsettledTradesToSellSecurities
Namespace Prefix: | sbsi_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- References No definition available. + Details
Name: | us-gaap_CommitmentsAndContingenciesDisclosureAbstract
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Amount of lessee's right to use underlying asset under operating lease. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 842 -SubTopic 20 -Name Accounting Standards Codification -Section 45 -Paragraph 1 -Subparagraph (a) -Publisher FASB -URI https://asc.fasb.org//1943274/2147479041/842-20-45-1 + Details
Name: | us-gaap_OperatingLeaseRightOfUseAsset
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Amount of increase in right-of-use asset obtained in exchange for operating lease liability. + References Reference 1: http://www.xbrl.org/2003/role/exampleRef -Topic 842 -SubTopic 20 -Name Accounting Standards Codification -Section 55 -Paragraph 53 -Publisher FASB -URI https://asc.fasb.org//1943274/2147479589/842-20-55-53 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 842 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 4 -Subparagraph (g)(2) -Publisher FASB -URI https://asc.fasb.org//1943274/2147478964/842-20-50-4 + Details
Name: | us-gaap_RightOfUseAssetObtainedInExchangeForOperatingLeaseLiability
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration