$SBSI
SOUTHSIDE BANCSHARES INC Stock $sbsi

$sbsi Overview Financials Valuation SEC Filings Company Website

2020 Q4 Form 10-Q Financial Statement

#000070543220000169 Filed on October 30, 2020

Income Statement

Concept	2020 Q4	2020 Q3	2019 Q3
Revenue	$56.90M	$55.68M	$60.56M
YoY Change	-6.0%	-8.06%	5.95%
Cost Of Revenue
YoY Change
Gross Profit
YoY Change
Gross Profit Margin
Selling, General & Admin
YoY Change
% of Gross Profit
Research & Development
YoY Change
% of Gross Profit
Depreciation & Amortization	$3.000M	$3.000M	$3.000M
YoY Change	0.0%	0.0%	-14.29%
% of Gross Profit
Operating Expenses
YoY Change
Operating Profit
YoY Change
Interest Expense	$8.197M	$9.091M	$18.18M
YoY Change	-52.77%	-50.0%	23.33%
% of Operating Profit
Other Income/Expense, Net
YoY Change
Pretax Income	$33.84M	$30.86M	$23.45M
YoY Change	67.6%	31.57%	4.26%
Income Tax	$4.265M	$3.800M	$3.661M
% Of Pretax Income	12.6%	12.31%	15.61%
Net Earnings	$29.57M	$27.07M	$19.79M
YoY Change	70.59%	36.79%	-2.52%
Net Earnings / Revenue	51.97%	48.63%	32.68%
Basic Earnings Per Share	$0.89	$0.82	$0.59
Diluted Earnings Per Share	$0.89	$0.82	$0.58
COMMON SHARES
Basic Shares Outstanding	33.07M shares	33.05M shares	33.77M shares
Diluted Shares Outstanding		33.10M shares	33.90M shares

Balance Sheet

Concept	2020 Q4	2020 Q3	2019 Q3
SHORT-TERM ASSETS
Cash & Short-Term Investments
YoY Change
Cash & Equivalents	$108.4M	$96.20M	$114.8M
Short-Term Investments
Other Short-Term Assets
YoY Change
Inventory
Prepaid Expenses
Receivables
Other Receivables
Total Short-Term Assets
YoY Change
LONG-TERM ASSETS
Property, Plant & Equipment	$144.6M	$147.2M	$141.7M
YoY Change	0.46%	3.87%	5.78%
Goodwill	$201.1M	$201.1M	$201.1M
YoY Change	0.0%	0.01%	-0.01%
Intangibles	$9.744M	$10.57M	$14.39M
YoY Change	-27.07%	-26.56%	-24.29%
Long-Term Investments	$11.90M	$12.10M	$12.40M
YoY Change	-3.25%	-2.42%
Other Assets			$0.00
YoY Change			-100.0%
Total Long-Term Assets
YoY Change
TOTAL ASSETS
Total Short-Term Assets
Total Long-Term Assets
Total Assets	$7.008B	$7.191B	$6.542B
YoY Change	3.84%	9.92%	7.15%
SHORT-TERM LIABILITIES
YoY Change
Accounts Payable
YoY Change
Accrued Expenses	$16.70M	$17.90M	$10.50M
YoY Change	63.73%	70.48%
Deferred Revenue
YoY Change
Short-Term Debt	$23.20M	$41.60M	$9.600M
YoY Change	-18.31%	333.33%	6.67%
Long-Term Debt Due
YoY Change
Total Short-Term Liabilities	$16.70M	$17.90M	$10.50M
YoY Change	63.73%	70.48%	16.67%
LONG-TERM LIABILITIES
Long-Term Debt	$257.5M	$159.0M	$158.8M
YoY Change	62.15%	0.13%	0.13%
Other Long-Term Liabilities	$55.10M	$67.80M	$75.00M
YoY Change	-17.27%	-9.6%	6.38%
Total Long-Term Liabilities	$312.6M	$226.8M	$233.8M
YoY Change	38.69%	-2.99%	2.05%
TOTAL LIABILITIES
Total Short-Term Liabilities	$16.70M	$17.90M	$10.50M
Total Long-Term Liabilities	$312.6M	$226.8M	$233.8M
Total Liabilities	$6.133B	$6.352B	$5.732B
YoY Change	3.17%	10.82%	7.08%
SHAREHOLDERS EQUITY
Retained Earnings	$111.2M	$93.92M	$74.48M
YoY Change	38.54%	26.1%	27.14%
Common Stock	$818.9M	$818.0M	$812.9M
YoY Change	0.6%	0.64%	0.49%
Preferred Stock
YoY Change
Treasury Stock (at cost)	$123.9M	$119.1M	$93.57M
YoY Change	31.82%	27.26%	103.57%
Treasury Stock Shares	4.984M shares	4.850M shares	4.083M shares
Shareholders Equity	$875.3M	$839.1M	$810.5M
YoY Change
Total Liabilities & Shareholders Equity	$7.008B	$7.191B	$6.542B
YoY Change	3.84%	9.92%	7.15%

Cashflow Statement

Concept	2020 Q4	2020 Q3	2019 Q3
OPERATING ACTIVITIES
Net Income	$29.57M	$27.07M	$19.79M
YoY Change	70.59%	36.79%	-2.52%
Depreciation, Depletion And Amortization	$3.000M	$3.000M	$3.000M
YoY Change	0.0%	0.0%	-14.29%
Cash From Operating Activities	$40.20M	$32.80M	$25.20M
YoY Change	95.15%	30.16%	-22.7%
INVESTING ACTIVITIES
Capital Expenditures	-$1.200M	-$2.300M	-$3.500M
YoY Change	-73.33%	-34.29%	-5.41%
Acquisitions
YoY Change
Other Investing Activities	$201.2M	$113.1M	-$180.1M
YoY Change	-194.28%	-162.8%	-277.26%
Cash From Investing Activities	$200.1M	$110.7M	-$183.7M
YoY Change	-191.87%	-160.26%	-287.83%
FINANCING ACTIVITIES
Cash Dividend Paid
YoY Change
Common Stock Issuance & Retirement, Net
YoY Change
Debt Paid & Issued, Net
YoY Change
Cash From Financing Activities	-228.1M	-148.1M	140.8M
YoY Change	-218.13%	-205.18%	-174.73%
NET CHANGE
Cash From Operating Activities	40.20M	32.80M	25.20M
Cash From Investing Activities	200.1M	110.7M	-183.7M
Cash From Financing Activities	-228.1M	-148.1M	140.8M
Net Change In Cash	12.20M	-4.600M	-17.70M
YoY Change	-397.56%	-74.01%	-69.48%
FREE CASH FLOW
Cash From Operating Activities	$40.20M	$32.80M	$25.20M
Capital Expenditures	-$1.200M	-$2.300M	-$3.500M
Free Cash Flow	$41.40M	$35.10M	$28.70M
YoY Change	64.94%	22.3%	-20.94%

Facts In Submission

Frame	Concept Type	Concept / XBRL Key	Value	Unit
	dei	Entity Central Index Key EntityCentralIndexKey	0000705432
	dei	Current Fiscal Year End Date CurrentFiscalYearEndDate	--12-31
	dei	Document Fiscal Year Focus DocumentFiscalYearFocus	2020
	dei	Document Fiscal Period Focus DocumentFiscalPeriodFocus	Q3
	dei	Amendment Flag AmendmentFlag	false
	dei	Document Type DocumentType	10-Q
	dei	Document Quarterly Report DocumentQuarterlyReport	true
	dei	Document Period End Date DocumentPeriodEndDate	2020-09-30
	dei	Local Phone Number LocalPhoneNumber	531-7111
	dei	Document Transition Report DocumentTransitionReport	false
	dei	Entity File Number EntityFileNumber	000-12247
	dei	Entity Registrant Name EntityRegistrantName	SOUTHSIDE BANCSHARES, INC.
	dei	Entity Incorporation State Country Code EntityIncorporationStateCountryCode	TX
	dei	Entity Tax Identification Number EntityTaxIdentificationNumber	75-1848732
	dei	Entity Address Address Line1 EntityAddressAddressLine1	1201 S. Beckham Avenue,
	dei	Entity Address City Or Town EntityAddressCityOrTown	Tyler,
	dei	Entity Address State Or Province EntityAddressStateOrProvince	TX
	dei	Entity Address Postal Zip Code EntityAddressPostalZipCode	75701
	dei	City Area Code CityAreaCode	903
	dei	Security12b Title Security12bTitle	Common Stock, $1.25 par value
	dei	Trading Symbol TradingSymbol	SBSI
	dei	Security Exchange Name SecurityExchangeName	NASDAQ
	dei	Entity Current Reporting Status EntityCurrentReportingStatus	Yes
	dei	Entity Interactive Data Current EntityInteractiveDataCurrent	Yes
	dei	Entity Filer Category EntityFilerCategory	Large Accelerated Filer
	dei	Entity Small Business EntitySmallBusiness	false
	dei	Entity Emerging Growth Company EntityEmergingGrowthCompany	false
	dei	Entity Shell Company EntityShellCompany	false
CY2020Q4	dei	Entity Common Stock Shares Outstanding EntityCommonStockSharesOutstanding	33072121	shares
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CY2019Q4	us-gaap	Cash And Due From Banks CashAndDueFromBanks	66949000	USD
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CY2019Q4	us-gaap	Goodwill Goodwill	201116000	USD
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CY2019Q3	sbsi	Fee And Commissions Depositor Account FeeAndCommissionsDepositorAccount	6753000	USD
	sbsi	Fee And Commissions Depositor Account FeeAndCommissionsDepositorAccount	17940000	USD
	sbsi	Fee And Commissions Depositor Account FeeAndCommissionsDepositorAccount	19391000	USD
CY2020Q3	us-gaap	Debt Securities Available For Sale Realized Gain Loss DebtSecuritiesAvailableForSaleRealizedGainLoss	78000	USD
CY2019Q3	us-gaap	Debt Securities Available For Sale Realized Gain Loss DebtSecuritiesAvailableForSaleRealizedGainLoss	42000	USD
	us-gaap	Debt Securities Available For Sale Realized Gain Loss DebtSecuritiesAvailableForSaleRealizedGainLoss	8281000	USD
	us-gaap	Debt Securities Available For Sale Realized Gain Loss DebtSecuritiesAvailableForSaleRealizedGainLoss	714000	USD
CY2020Q3	us-gaap	Gain Loss On Sales Of Loans Net GainLossOnSalesOfLoansNet	1071000	USD
CY2019Q3	us-gaap	Gain Loss On Sales Of Loans Net GainLossOnSalesOfLoansNet	131000	USD
	us-gaap	Gain Loss On Sales Of Loans Net GainLossOnSalesOfLoansNet	1924000	USD
	us-gaap	Gain Loss On Sales Of Loans Net GainLossOnSalesOfLoansNet	405000	USD
CY2020Q3	sbsi	Fees And Commissions Fiduciary And Trust Activity FeesAndCommissionsFiduciaryAndTrustActivity	1253000	USD
CY2019Q3	sbsi	Fees And Commissions Fiduciary And Trust Activity FeesAndCommissionsFiduciaryAndTrustActivity	1523000	USD
	sbsi	Fees And Commissions Fiduciary And Trust Activity FeesAndCommissionsFiduciaryAndTrustActivity	3779000	USD
	sbsi	Fees And Commissions Fiduciary And Trust Activity FeesAndCommissionsFiduciaryAndTrustActivity	4584000	USD
CY2020Q3	us-gaap	Bank Owned Life Insurance Income BankOwnedLifeInsuranceIncome	680000	USD
CY2019Q3	us-gaap	Bank Owned Life Insurance Income BankOwnedLifeInsuranceIncome	622000	USD
	us-gaap	Bank Owned Life Insurance Income BankOwnedLifeInsuranceIncome	1899000	USD
	us-gaap	Bank Owned Life Insurance Income BankOwnedLifeInsuranceIncome	1725000	USD
CY2020Q3	us-gaap	Brokerage Commissions Revenue BrokerageCommissionsRevenue	564000	USD
CY2019Q3	us-gaap	Brokerage Commissions Revenue BrokerageCommissionsRevenue	555000	USD
	us-gaap	Brokerage Commissions Revenue BrokerageCommissionsRevenue	1643000	USD
	us-gaap	Brokerage Commissions Revenue BrokerageCommissionsRevenue	1549000	USD
CY2020Q3	us-gaap	Noninterest Income Other Operating Income NoninterestIncomeOtherOperatingIncome	1366000	USD
CY2019Q3	us-gaap	Noninterest Income Other Operating Income NoninterestIncomeOtherOperatingIncome	1485000	USD
	us-gaap	Noninterest Income Other Operating Income NoninterestIncomeOtherOperatingIncome	3366000	USD
	us-gaap	Noninterest Income Other Operating Income NoninterestIncomeOtherOperatingIncome	3535000	USD
CY2020Q3	us-gaap	Noninterest Income NoninterestIncome	11141000	USD
CY2019Q3	us-gaap	Noninterest Income NoninterestIncome	11111000	USD
	us-gaap	Noninterest Income NoninterestIncome	38832000	USD
	us-gaap	Noninterest Income NoninterestIncome	31903000	USD
CY2020Q3	us-gaap	Labor And Related Expense LaborAndRelatedExpense	19344000	USD
CY2019Q3	us-gaap	Labor And Related Expense LaborAndRelatedExpense	18388000	USD
	us-gaap	Labor And Related Expense LaborAndRelatedExpense	57616000	USD
	us-gaap	Labor And Related Expense LaborAndRelatedExpense	54325000	USD
CY2020Q3	us-gaap	Occupancy Net OccupancyNet	3595000	USD
CY2019Q3	us-gaap	Occupancy Net OccupancyNet	3430000	USD
	us-gaap	Occupancy Net OccupancyNet	10574000	USD
	us-gaap	Occupancy Net OccupancyNet	9894000	USD
CY2020Q3	us-gaap	Marketing And Advertising Expense MarketingAndAdvertisingExpense	519000	USD
CY2019Q3	us-gaap	Marketing And Advertising Expense MarketingAndAdvertisingExpense	593000	USD
	us-gaap	Marketing And Advertising Expense MarketingAndAdvertisingExpense	1643000	USD
	us-gaap	Marketing And Advertising Expense MarketingAndAdvertisingExpense	2173000	USD
CY2020Q3	sbsi	Atm Expense ATMExpense	271000	USD
CY2019Q3	sbsi	Atm Expense ATMExpense	232000	USD
	sbsi	Atm Expense ATMExpense	728000	USD
	sbsi	Atm Expense ATMExpense	658000	USD
CY2020Q3	us-gaap	Professional Fees ProfessionalFees	961000	USD
CY2019Q3	us-gaap	Professional Fees ProfessionalFees	1192000	USD
	us-gaap	Professional Fees ProfessionalFees	3238000	USD
	us-gaap	Professional Fees ProfessionalFees	3575000	USD
CY2020Q3	us-gaap	Information Technology And Data Processing InformationTechnologyAndDataProcessing	1215000	USD
CY2019Q3	us-gaap	Information Technology And Data Processing InformationTechnologyAndDataProcessing	1116000	USD
	us-gaap	Information Technology And Data Processing InformationTechnologyAndDataProcessing	3737000	USD
	us-gaap	Information Technology And Data Processing InformationTechnologyAndDataProcessing	3278000	USD
CY2020Q3	us-gaap	Communication Communication	495000	USD
CY2019Q3	us-gaap	Communication Communication	480000	USD
	us-gaap	Communication Communication	1494000	USD
	us-gaap	Communication Communication	1456000	USD
CY2020Q3	us-gaap	Federal Deposit Insurance Corporation Premium Expense FederalDepositInsuranceCorporationPremiumExpense	469000	USD
CY2019Q3	us-gaap	Federal Deposit Insurance Corporation Premium Expense FederalDepositInsuranceCorporationPremiumExpense	0	USD
	us-gaap	Federal Deposit Insurance Corporation Premium Expense FederalDepositInsuranceCorporationPremiumExpense	668000	USD
	us-gaap	Federal Deposit Insurance Corporation Premium Expense FederalDepositInsuranceCorporationPremiumExpense	859000	USD
CY2020Q3	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	881000	USD
CY2019Q3	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	1080000	USD
	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	2792000	USD
	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	3388000	USD
CY2020Q3	us-gaap	Other Noninterest Expense OtherNoninterestExpense	3866000	USD
CY2019Q3	us-gaap	Other Noninterest Expense OtherNoninterestExpense	2515000	USD
	us-gaap	Other Noninterest Expense OtherNoninterestExpense	9502000	USD
	us-gaap	Other Noninterest Expense OtherNoninterestExpense	8747000	USD
CY2020Q3	us-gaap	Noninterest Expense NoninterestExpense	31616000	USD
CY2019Q3	us-gaap	Noninterest Expense NoninterestExpense	29026000	USD
	us-gaap	Noninterest Expense NoninterestExpense	91992000	USD
	us-gaap	Noninterest Expense NoninterestExpense	88353000	USD
CY2020Q3	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	30857000	USD
CY2019Q3	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	23453000	USD
	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	59652000	USD
	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	67586000	USD
CY2020Q3	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	3783000	USD
CY2019Q3	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	3661000	USD
	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	7071000	USD
	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	10367000	USD
CY2020Q3	us-gaap	Net Income Loss NetIncomeLoss	27074000	USD
CY2019Q3	us-gaap	Net Income Loss NetIncomeLoss	19792000	USD
	us-gaap	Net Income Loss NetIncomeLoss	52581000	USD
	us-gaap	Net Income Loss NetIncomeLoss	57219000	USD
CY2020Q3	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.82
CY2019Q3	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.59
	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	1.58
	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	1.70
CY2020Q3	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.82
CY2019Q3	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.58
	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	1.58
	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	1.69
CY2020Q3	us-gaap	Common Stock Dividends Per Share Cash Paid CommonStockDividendsPerShareCashPaid	0.31
CY2019Q3	us-gaap	Common Stock Dividends Per Share Cash Paid CommonStockDividendsPerShareCashPaid	0.31
	us-gaap	Common Stock Dividends Per Share Cash Paid CommonStockDividendsPerShareCashPaid	0.93
	us-gaap	Common Stock Dividends Per Share Cash Paid CommonStockDividendsPerShareCashPaid	0.92
CY2020Q3	us-gaap	Net Income Loss NetIncomeLoss	27074000	USD
CY2019Q3	us-gaap	Net Income Loss NetIncomeLoss	19792000	USD
	us-gaap	Net Income Loss NetIncomeLoss	52581000	USD
	us-gaap	Net Income Loss NetIncomeLoss	57219000	USD
CY2020Q3	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Before Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodBeforeTax	1601000	USD
CY2019Q3	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Before Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodBeforeTax	17334000	USD
	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Before Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodBeforeTax	88900000	USD
	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Before Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodBeforeTax	96156000	USD
CY2020Q3	sbsi	Amortizationof Unrealized Gains Losseson Securities Transferred Between Availablefor Sale And Heldto Maturity Debt Securities Before Tax AmortizationofUnrealizedGainsLossesonSecuritiesTransferredBetweenAvailableforSaleAndHeldtoMaturityDebtSecuritiesBeforeTax	-394000	USD
CY2019Q3	sbsi	Amortizationof Unrealized Gains Losseson Securities Transferred Between Availablefor Sale And Heldto Maturity Debt Securities Before Tax AmortizationofUnrealizedGainsLossesonSecuritiesTransferredBetweenAvailableforSaleAndHeldtoMaturityDebtSecuritiesBeforeTax	-112000	USD
	sbsi	Amortizationof Unrealized Gains Losseson Securities Transferred Between Availablefor Sale And Heldto Maturity Debt Securities Before Tax AmortizationofUnrealizedGainsLossesonSecuritiesTransferredBetweenAvailableforSaleAndHeldtoMaturityDebtSecuritiesBeforeTax	-730000	USD
	sbsi	Amortizationof Unrealized Gains Losseson Securities Transferred Between Availablefor Sale And Heldto Maturity Debt Securities Before Tax AmortizationofUnrealizedGainsLossesonSecuritiesTransferredBetweenAvailableforSaleAndHeldtoMaturityDebtSecuritiesBeforeTax	-683000	USD
CY2020Q3	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci For Sale Of Securities Before Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesBeforeTax	78000	USD
CY2019Q3	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci For Sale Of Securities Before Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesBeforeTax	42000	USD
	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci For Sale Of Securities Before Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesBeforeTax	8281000	USD
	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci For Sale Of Securities Before Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesBeforeTax	714000	USD
CY2020Q3	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss Before Reclassification And Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossBeforeReclassificationAndTax	-197000	USD
CY2019Q3	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss Before Reclassification And Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossBeforeReclassificationAndTax	-2619000	USD
	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss Before Reclassification And Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossBeforeReclassificationAndTax	-25236000	USD
	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss Before Reclassification And Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossBeforeReclassificationAndTax	-11392000	USD
CY2020Q3	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss Reclassification Before Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossReclassificationBeforeTax	-1587000	USD
CY2019Q3	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss Reclassification Before Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossReclassificationBeforeTax	499000	USD
	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss Reclassification Before Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossReclassificationBeforeTax	-2283000	USD
	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss Reclassification Before Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossReclassificationBeforeTax	1809000	USD
CY2020Q3	sbsi	Other Comprehensive Income Loss Defined Benefit Plan Gain Lossand Prior Service Cost Credit Reclassification Adjustmentfrom Aoc Ibefore Tax OtherComprehensiveIncomeLossDefinedBenefitPlanGainLossandPriorServiceCostCreditReclassificationAdjustmentfromAOCIbeforeTax	819000	USD
CY2019Q3	sbsi	Other Comprehensive Income Loss Defined Benefit Plan Gain Lossand Prior Service Cost Credit Reclassification Adjustmentfrom Aoc Ibefore Tax OtherComprehensiveIncomeLossDefinedBenefitPlanGainLossandPriorServiceCostCreditReclassificationAdjustmentfromAOCIbeforeTax	595000	USD
	sbsi	Other Comprehensive Income Loss Defined Benefit Plan Gain Lossand Prior Service Cost Credit Reclassification Adjustmentfrom Aoc Ibefore Tax OtherComprehensiveIncomeLossDefinedBenefitPlanGainLossandPriorServiceCostCreditReclassificationAdjustmentfromAOCIbeforeTax	2207000	USD
	sbsi	Other Comprehensive Income Loss Defined Benefit Plan Gain Lossand Prior Service Cost Credit Reclassification Adjustmentfrom Aoc Ibefore Tax OtherComprehensiveIncomeLossDefinedBenefitPlanGainLossandPriorServiceCostCreditReclassificationAdjustmentfromAOCIbeforeTax	1784000	USD
CY2020Q3	sbsi	Other Comprehensive Income Loss Defined Benefit Plan Prior Service Cost Credit Plan Amendment Before Tax OtherComprehensiveIncomeLossDefinedBenefitPlanPriorServiceCostCreditPlanAmendmentBeforeTax	0	USD
CY2019Q3	sbsi	Other Comprehensive Income Loss Defined Benefit Plan Prior Service Cost Credit Plan Amendment Before Tax OtherComprehensiveIncomeLossDefinedBenefitPlanPriorServiceCostCreditPlanAmendmentBeforeTax	0	USD
	sbsi	Other Comprehensive Income Loss Defined Benefit Plan Prior Service Cost Credit Plan Amendment Before Tax OtherComprehensiveIncomeLossDefinedBenefitPlanPriorServiceCostCreditPlanAmendmentBeforeTax	163000	USD
	sbsi	Other Comprehensive Income Loss Defined Benefit Plan Prior Service Cost Credit Plan Amendment Before Tax OtherComprehensiveIncomeLossDefinedBenefitPlanPriorServiceCostCreditPlanAmendmentBeforeTax	0	USD
CY2020Q3	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Net Unamortized Gain Loss Arising During Period Before Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansNetUnamortizedGainLossArisingDuringPeriodBeforeTax	0	USD
CY2019Q3	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Net Unamortized Gain Loss Arising During Period Before Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansNetUnamortizedGainLossArisingDuringPeriodBeforeTax	0	USD
	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Net Unamortized Gain Loss Arising During Period Before Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansNetUnamortizedGainLossArisingDuringPeriodBeforeTax	-7558000	USD
	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Net Unamortized Gain Loss Arising During Period Before Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansNetUnamortizedGainLossArisingDuringPeriodBeforeTax	0	USD
CY2020Q3	us-gaap	Other Comprehensive Income Loss Before Tax OtherComprehensiveIncomeLossBeforeTax	4126000	USD
CY2019Q3	us-gaap	Other Comprehensive Income Loss Before Tax OtherComprehensiveIncomeLossBeforeTax	14881000	USD
	us-gaap	Other Comprehensive Income Loss Before Tax OtherComprehensiveIncomeLossBeforeTax	53208000	USD
	us-gaap	Other Comprehensive Income Loss Before Tax OtherComprehensiveIncomeLossBeforeTax	84708000	USD
CY2020Q3	us-gaap	Other Comprehensive Income Loss Tax OtherComprehensiveIncomeLossTax	866000	USD
CY2019Q3	us-gaap	Other Comprehensive Income Loss Tax OtherComprehensiveIncomeLossTax	3125000	USD
CY2020Q1	us-gaap	Treasury Stock Value Acquired Cost Method TreasuryStockValueAcquiredCostMethod	25842000	USD
CY2020Q1	us-gaap	Adjustments To Additional Paid In Capital Sharebased Compensation Requisite Service Period Recognition Value AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue	695000	USD
CY2020Q1	us-gaap	Stock Issued During Period Shares Share Based Compensation StockIssuedDuringPeriodSharesShareBasedCompensation	47428	shares
CY2020Q1	us-gaap	Stock Issued During Period Value Share Based Compensation StockIssuedDuringPeriodValueShareBasedCompensation	1088000	USD
	us-gaap	Other Comprehensive Income Loss Tax OtherComprehensiveIncomeLossTax	11173000	USD
	us-gaap	Other Comprehensive Income Loss Tax OtherComprehensiveIncomeLossTax	17789000	USD
CY2020Q3	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	3260000	USD
CY2019Q3	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	11756000	USD
	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	42035000	USD
	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	66919000	USD
CY2020Q3	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	30334000	USD
CY2019Q3	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	31548000	USD
	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	94616000	USD
	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	124138000	USD
CY2019Q4	us-gaap	Stockholders Equity StockholdersEquity	804580000	USD
CY2020Q1	us-gaap	Net Income Loss NetIncomeLoss	3953000	USD
CY2020Q1	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	29303000	USD
CY2020Q1	us-gaap	Stock Issued During Period Shares Dividend Reinvestment Plan StockIssuedDuringPeriodSharesDividendReinvestmentPlan	10607	shares
CY2020Q1	us-gaap	Stock Issued During Period Value Dividend Reinvestment Plan StockIssuedDuringPeriodValueDividendReinvestmentPlan	347000	USD
CY2020Q1	us-gaap	Treasury Stock Shares Acquired TreasuryStockSharesAcquired	869723	shares
CY2020Q1	us-gaap	Common Stock Dividends Per Share Cash Paid CommonStockDividendsPerShareCashPaid	0.31
CY2020Q1	us-gaap	Dividends Common Stock Cash DividendsCommonStockCash	10494000	USD
CY2020Q1	us-gaap	Stockholders Equity StockholdersEquity	795800000	USD
CY2020Q2	us-gaap	Net Income Loss NetIncomeLoss	21554000	USD
CY2020Q2	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	9472000	USD
CY2020Q2	us-gaap	Stock Issued During Period Shares Dividend Reinvestment Plan StockIssuedDuringPeriodSharesDividendReinvestmentPlan	11532	shares
CY2020Q2	us-gaap	Stock Issued During Period Value Dividend Reinvestment Plan StockIssuedDuringPeriodValueDividendReinvestmentPlan	336000	USD
CY2020Q2	us-gaap	Adjustments To Additional Paid In Capital Sharebased Compensation Requisite Service Period Recognition Value AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue	772000	USD
CY2020Q2	us-gaap	Stock Issued During Period Shares Share Based Compensation StockIssuedDuringPeriodSharesShareBasedCompensation	9342	shares
CY2020Q2	us-gaap	Stock Issued During Period Value Share Based Compensation StockIssuedDuringPeriodValueShareBasedCompensation	-96000	USD
CY2020Q2	us-gaap	Common Stock Dividends Per Share Cash Paid CommonStockDividendsPerShareCashPaid	0.31
CY2020Q2	us-gaap	Dividends Common Stock Cash DividendsCommonStockCash	10233000	USD
CY2020Q2	us-gaap	Stockholders Equity StockholdersEquity	817605000	USD
CY2020Q3	us-gaap	Net Income Loss NetIncomeLoss	27074000	USD
CY2020Q3	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	3260000	USD
CY2020Q3	us-gaap	Stock Issued During Period Shares Dividend Reinvestment Plan StockIssuedDuringPeriodSharesDividendReinvestmentPlan	12201	shares
CY2020Q3	us-gaap	Stock Issued During Period Value Dividend Reinvestment Plan StockIssuedDuringPeriodValueDividendReinvestmentPlan	337000	USD
CY2020Q3	us-gaap	Adjustments To Additional Paid In Capital Sharebased Compensation Requisite Service Period Recognition Value AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue	786000	USD
CY2020Q3	us-gaap	Stock Issued During Period Shares Share Based Compensation StockIssuedDuringPeriodSharesShareBasedCompensation	27477	shares
CY2020Q3	us-gaap	Stock Issued During Period Value Share Based Compensation StockIssuedDuringPeriodValueShareBasedCompensation	331000	USD
CY2020Q3	us-gaap	Common Stock Dividends Per Share Cash Paid CommonStockDividendsPerShareCashPaid	0.31
CY2020Q3	us-gaap	Dividends Common Stock Cash DividendsCommonStockCash	10245000	USD
CY2020Q3	us-gaap	Stockholders Equity StockholdersEquity	839148000	USD
CY2018Q4	us-gaap	Stockholders Equity StockholdersEquity	731291000	USD
CY2019Q1	us-gaap	Net Income Loss NetIncomeLoss	18817000	USD
CY2019Q1	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	34455000	USD
CY2019Q1	us-gaap	Stock Issued During Period Shares Dividend Reinvestment Plan StockIssuedDuringPeriodSharesDividendReinvestmentPlan	10565	shares
CY2019Q1	us-gaap	Stock Issued During Period Value Dividend Reinvestment Plan StockIssuedDuringPeriodValueDividendReinvestmentPlan	355000	USD
CY2019Q1	us-gaap	Treasury Stock Shares Acquired TreasuryStockSharesAcquired	40852	shares
CY2019Q1	us-gaap	Treasury Stock Value Acquired Cost Method TreasuryStockValueAcquiredCostMethod	1325000	USD
CY2019Q1	us-gaap	Adjustments To Additional Paid In Capital Sharebased Compensation Requisite Service Period Recognition Value AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue	661000	USD
CY2019Q1	us-gaap	Stock Issued During Period Shares Share Based Compensation StockIssuedDuringPeriodSharesShareBasedCompensation	23617	shares
CY2019Q1	us-gaap	Stock Issued During Period Value Share Based Compensation StockIssuedDuringPeriodValueShareBasedCompensation	338000	USD
CY2019Q1	us-gaap	Common Stock Dividends Per Share Cash Paid CommonStockDividendsPerShareCashPaid	0.30
CY2019Q1	us-gaap	Dividends Common Stock Cash DividendsCommonStockCash	10107000	USD
CY2019Q1	us-gaap	Stockholders Equity StockholdersEquity	758033000	USD
CY2019Q2	us-gaap	Net Income Loss NetIncomeLoss	18610000	USD
CY2019Q2	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	20708000	USD
CY2019Q2	us-gaap	Stock Issued During Period Shares Dividend Reinvestment Plan StockIssuedDuringPeriodSharesDividendReinvestmentPlan	10570	shares
CY2019Q2	us-gaap	Stock Issued During Period Value Dividend Reinvestment Plan StockIssuedDuringPeriodValueDividendReinvestmentPlan	349000	USD
CY2019Q2	us-gaap	Adjustments To Additional Paid In Capital Sharebased Compensation Requisite Service Period Recognition Value AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue	571000	USD
CY2019Q2	us-gaap	Stock Issued During Period Shares Share Based Compensation StockIssuedDuringPeriodSharesShareBasedCompensation	20115	shares
CY2019Q2	us-gaap	Stock Issued During Period Value Share Based Compensation StockIssuedDuringPeriodValueShareBasedCompensation	-53000	USD
CY2019Q2	us-gaap	Common Stock Dividends Per Share Cash Paid CommonStockDividendsPerShareCashPaid	0.31
CY2019Q2	us-gaap	Dividends Common Stock Cash DividendsCommonStockCash	10453000	USD
CY2019Q2	us-gaap	Stockholders Equity StockholdersEquity	787765000	USD
CY2019Q3	us-gaap	Net Income Loss NetIncomeLoss	19792000	USD
CY2019Q3	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	11756000	USD
CY2019Q3	us-gaap	Stock Issued During Period Shares Dividend Reinvestment Plan StockIssuedDuringPeriodSharesDividendReinvestmentPlan	10744	shares
CY2019Q3	us-gaap	Stock Issued During Period Value Dividend Reinvestment Plan StockIssuedDuringPeriodValueDividendReinvestmentPlan	353000	USD
CY2019Q3	us-gaap	Adjustments To Additional Paid In Capital Sharebased Compensation Requisite Service Period Recognition Value AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue	522000	USD
CY2019Q3	us-gaap	Stock Issued During Period Shares Share Based Compensation StockIssuedDuringPeriodSharesShareBasedCompensation	35070	shares
CY2019Q3	us-gaap	Stock Issued During Period Value Share Based Compensation StockIssuedDuringPeriodValueShareBasedCompensation	736000	USD
CY2019Q3	us-gaap	Common Stock Dividends Per Share Cash Paid CommonStockDividendsPerShareCashPaid	0.31
CY2019Q3	us-gaap	Dividends Common Stock Cash DividendsCommonStockCash	10471000	USD
CY2019Q3	us-gaap	Stockholders Equity StockholdersEquity	810453000	USD
	us-gaap	Profit Loss ProfitLoss	52581000	USD
	us-gaap	Profit Loss ProfitLoss	57219000	USD
	us-gaap	Depreciation Depletion And Amortization DepreciationDepletionAndAmortization	9128000	USD
	us-gaap	Depreciation Depletion And Amortization DepreciationDepletionAndAmortization	9110000	USD
	us-gaap	Accretion Amortization Of Discounts And Premiums Investments AccretionAmortizationOfDiscountsAndPremiumsInvestments	-17954000	USD
	us-gaap	Accretion Amortization Of Discounts And Premiums Investments AccretionAmortizationOfDiscountsAndPremiumsInvestments	-9370000	USD
	us-gaap	Investment Income Net Amortization Of Discount And Premium InvestmentIncomeNetAmortizationOfDiscountAndPremium	847000	USD
	us-gaap	Investment Income Net Amortization Of Discount And Premium InvestmentIncomeNetAmortizationOfDiscountAndPremium	1056000	USD
	us-gaap	Provision For Loan Lease And Other Losses ProvisionForLoanLeaseAndOtherLosses	25746000	USD
	us-gaap	Provision For Loan And Lease Losses ProvisionForLoanAndLeaseLosses	2593000	USD
	us-gaap	Share Based Compensation ShareBasedCompensation	2253000	USD
	us-gaap	Share Based Compensation ShareBasedCompensation	1754000	USD
	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	-4305000	USD
	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	-4000	USD
	us-gaap	Debt Securities Available For Sale Realized Gain Loss DebtSecuritiesAvailableForSaleRealizedGainLoss	8281000	USD
	us-gaap	Debt Securities Available For Sale Realized Gain Loss DebtSecuritiesAvailableForSaleRealizedGainLoss	714000	USD
	us-gaap	Gain Loss On Disposition Of Assets GainLossOnDispositionOfAssets	-821000	USD
	us-gaap	Gain Loss On Disposition Of Assets GainLossOnDispositionOfAssets	-258000	USD
	us-gaap	Proceeds From Sale Of Mortgage Loans Held For Sale ProceedsFromSaleOfMortgageLoansHeldForSale	48343000	USD
	us-gaap	Proceeds From Sale Of Mortgage Loans Held For Sale ProceedsFromSaleOfMortgageLoansHeldForSale	16862000	USD
	us-gaap	Payments For Origination And Purchases Of Loans Held For Sale PaymentsForOriginationAndPurchasesOfLoansHeldForSale	56646000	USD
	us-gaap	Payments For Origination And Purchases Of Loans Held For Sale PaymentsForOriginationAndPurchasesOfLoansHeldForSale	17261000	USD
	us-gaap	Gains Losses On Sales Of Other Real Estate GainsLossesOnSalesOfOtherRealEstate	-129000	USD
	us-gaap	Gains Losses On Sales Of Other Real Estate GainsLossesOnSalesOfOtherRealEstate	93000	USD
	us-gaap	Defined Benefit Plan Recognized Net Gain Loss Due To Curtailments DefinedBenefitPlanRecognizedNetGainLossDueToCurtailments	-163000	USD
	us-gaap	Proceeds From Sale Of Foreclosed Assets ProceedsFromSaleOfForeclosedAssets	275000	USD
	us-gaap	Defined Benefit Plan Recognized Net Gain Loss Due To Curtailments DefinedBenefitPlanRecognizedNetGainLossDueToCurtailments	0	USD
	us-gaap	Increase Decrease In Accrued Interest Receivable Net IncreaseDecreaseInAccruedInterestReceivableNet	1987000	USD
	us-gaap	Increase Decrease In Accrued Interest Receivable Net IncreaseDecreaseInAccruedInterestReceivableNet	-4804000	USD
	us-gaap	Increase Decrease In Other Operating Assets IncreaseDecreaseInOtherOperatingAssets	35530000	USD
	us-gaap	Increase Decrease In Other Operating Assets IncreaseDecreaseInOtherOperatingAssets	15280000	USD
	us-gaap	Increase Decrease In Interest Payable Net IncreaseDecreaseInInterestPayableNet	-3673000	USD
	us-gaap	Increase Decrease In Interest Payable Net IncreaseDecreaseInInterestPayableNet	16000	USD
	us-gaap	Increase Decrease In Other Operating Liabilities IncreaseDecreaseInOtherOperatingLiabilities	4402000	USD
	us-gaap	Increase Decrease In Other Operating Liabilities IncreaseDecreaseInOtherOperatingLiabilities	-7624000	USD
	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	50251000	USD
	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	59954000	USD
	us-gaap	Payments To Acquire Available For Sale Securities Debt PaymentsToAcquireAvailableForSaleSecuritiesDebt	821232000	USD
	us-gaap	Payments To Acquire Available For Sale Securities Debt PaymentsToAcquireAvailableForSaleSecuritiesDebt	999403000	USD
	us-gaap	Proceeds From Sale Of Available For Sale Securities Debt ProceedsFromSaleOfAvailableForSaleSecuritiesDebt	291581000	USD
	us-gaap	Proceeds From Sale Of Available For Sale Securities Debt ProceedsFromSaleOfAvailableForSaleSecuritiesDebt	728107000	USD
	us-gaap	Proceeds From Maturities Prepayments And Calls Of Available For Sale Securities ProceedsFromMaturitiesPrepaymentsAndCallsOfAvailableForSaleSecurities	316072000	USD
	us-gaap	Proceeds From Maturities Prepayments And Calls Of Available For Sale Securities ProceedsFromMaturitiesPrepaymentsAndCallsOfAvailableForSaleSecurities	114739000	USD
	us-gaap	Proceeds From Maturities Prepayments And Calls Of Held To Maturity Securities ProceedsFromMaturitiesPrepaymentsAndCallsOfHeldToMaturitySecurities	19820000	USD
	us-gaap	Proceeds From Maturities Prepayments And Calls Of Held To Maturity Securities ProceedsFromMaturitiesPrepaymentsAndCallsOfHeldToMaturitySecurities	21809000	USD
	us-gaap	Proceeds From Sale Of Federal Reserve Stock ProceedsFromSaleOfFederalReserveStock	20000000	USD
	us-gaap	Proceeds From Sale Of Federal Reserve Stock ProceedsFromSaleOfFederalReserveStock	8788000	USD
	us-gaap	Payments To Acquire Federal Reserve Stock PaymentsToAcquireFederalReserveStock	5483000	USD
	us-gaap	Payments To Acquire Federal Reserve Stock PaymentsToAcquireFederalReserveStock	21504000	USD
	us-gaap	Payments To Acquire Finance Receivables PaymentsToAcquireFinanceReceivables	222342000	USD
	us-gaap	Payments To Acquire Finance Receivables PaymentsToAcquireFinanceReceivables	191116000	USD
	us-gaap	Payments To Acquire Property Plant And Equipment PaymentsToAcquirePropertyPlantAndEquipment	10216000	USD
	us-gaap	Payments To Acquire Property Plant And Equipment PaymentsToAcquirePropertyPlantAndEquipment	11449000	USD
	us-gaap	Proceeds From Sale Of Property Plant And Equipment ProceedsFromSaleOfPropertyPlantAndEquipment	114000	USD
	us-gaap	Proceeds From Sale Of Property Plant And Equipment ProceedsFromSaleOfPropertyPlantAndEquipment	94000	USD
	us-gaap	Proceeds From Sale Of Wholly Owned Real Estate And Real Estate Acquired In Settlement Of Loans ProceedsFromSaleOfWhollyOwnedRealEstateAndRealEstateAcquiredInSettlementOfLoans	277000	USD
	us-gaap	Proceeds From Sale Of Wholly Owned Real Estate And Real Estate Acquired In Settlement Of Loans ProceedsFromSaleOfWhollyOwnedRealEstateAndRealEstateAcquiredInSettlementOfLoans	674000	USD
	us-gaap	Payments To Acquire Life Insurance Policies PaymentsToAcquireLifeInsurancePolicies	12500000	USD
	us-gaap	Payments To Acquire Life Insurance Policies PaymentsToAcquireLifeInsurancePolicies	0	USD
	us-gaap	Proceeds From Sale Of Foreclosed Assets ProceedsFromSaleOfForeclosedAssets	158000	USD
	us-gaap	Net Change Interest And Noninterest Bearing Deposits Domestic NetChangeInterestAndNoninterestBearingDepositsDomestic	80711000	USD
	us-gaap	Increase Decrease In Federal Funds Purchased And Securities Sold Under Agreements To Repurchase Net IncreaseDecreaseInFederalFundsPurchasedAndSecuritiesSoldUnderAgreementsToRepurchaseNet	13210000	USD
	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-423751000	USD
	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-348986000	USD
	us-gaap	Net Change Interest And Noninterest Bearing Deposits Domestic NetChangeInterestAndNoninterestBearingDepositsDomestic	420068000	USD
	us-gaap	Increase Decrease In Federal Funds Purchased And Securities Sold Under Agreements To Repurchase Net IncreaseDecreaseInFederalFundsPurchasedAndSecuritiesSoldUnderAgreementsToRepurchaseNet	-27184000	USD
	us-gaap	Proceeds From Federal Home Loan Bank Borrowings ProceedsFromFederalHomeLoanBankBorrowings	10135401000	USD
	us-gaap	Proceeds From Federal Home Loan Bank Borrowings ProceedsFromFederalHomeLoanBankBorrowings	4368700000	USD
	us-gaap	Repayments Of Federal Home Loan Bank Borrowings RepaymentsOfFederalHomeLoanBankBorrowings	10155201000	USD
	us-gaap	Repayments Of Federal Home Loan Bank Borrowings RepaymentsOfFederalHomeLoanBankBorrowings	4108812000	USD
	us-gaap	Proceeds From Stock Options Exercised ProceedsFromStockOptionsExercised	1502000	USD
	us-gaap	Proceeds From Stock Options Exercised ProceedsFromStockOptionsExercised	1284000	USD
	us-gaap	Payments Related To Tax Withholding For Share Based Compensation PaymentsRelatedToTaxWithholdingForShareBasedCompensation	179000	USD
	us-gaap	Payments Related To Tax Withholding For Share Based Compensation PaymentsRelatedToTaxWithholdingForShareBasedCompensation	263000	USD
	us-gaap	Payments For Repurchase Of Common Stock PaymentsForRepurchaseOfCommonStock	25842000	USD
	us-gaap	Payments For Repurchase Of Common Stock PaymentsForRepurchaseOfCommonStock	1325000	USD
	us-gaap	Proceeds From Issuance Of Common Stock Dividend Reinvestment Plan ProceedsFromIssuanceOfCommonStockDividendReinvestmentPlan	1020000	USD
	us-gaap	Proceeds From Issuance Of Common Stock Dividend Reinvestment Plan ProceedsFromIssuanceOfCommonStockDividendReinvestmentPlan	1057000	USD
	us-gaap	Payments Of Dividends Common Stock PaymentsOfDividendsCommonStock	30972000	USD
	us-gaap	Payments Of Dividends Common Stock PaymentsOfDividendsCommonStock	31031000	USD
	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	359007000	USD
	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	283137000	USD
	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Including Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect	-14493000	USD
	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Including Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect	-5895000	USD
CY2019Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	110697000	USD
CY2018Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	120719000	USD
CY2020Q3	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	96204000	USD
CY2019Q3	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	114824000	USD
	us-gaap	Interest Paid Net InterestPaidNet	40039000	USD
	us-gaap	Interest Paid Net InterestPaidNet	53610000	USD
	us-gaap	Income Taxes Paid IncomeTaxesPaid	9000000	USD
	us-gaap	Income Taxes Paid IncomeTaxesPaid	7500000	USD
	sbsi	Loans Transferred To Other Repossessed Assets And Real Estate Through Foreclosure LoansTransferredToOtherRepossessedAssetsAndRealEstateThroughForeclosure	627000	USD
	sbsi	Loans Transferred To Other Repossessed Assets And Real Estate Through Foreclosure LoansTransferredToOtherRepossessedAssetsAndRealEstateThroughForeclosure	606000	USD
CY2020Q3	sbsi	Unsettled Trades To Purchase Securities Liability UnsettledTradesToPurchaseSecuritiesLiability	7294000	USD
CY2019Q3	sbsi	Unsettled Trades To Purchase Securities Liability UnsettledTradesToPurchaseSecuritiesLiability	30270000	USD
CY2020Q1	us-gaap	Financing Receivable Allowance For Credit Losses FinancingReceivableAllowanceForCreditLosses	24797000	USD
CY2020Q1	us-gaap	Off Balance Sheet Credit Loss Liability OffBalanceSheetCreditLossLiability	1455000	USD
	us-gaap	Revenue Recognition Interest RevenueRecognitionInterest	Accrued Interest. Accrued interest for our loans and debt securities, included in interest receivable on our consolidated balance sheets, is excluded from the estimate of allowance for credit losses (“ACL”).
CY2020Q3	us-gaap	Debt Securities Held To Maturity Allowance For Credit Loss DebtSecuritiesHeldToMaturityAllowanceForCreditLoss	0	USD
	us-gaap	Financing Receivable Allowance For Credit Losses Policy For Uncollectible Amounts FinancingReceivableAllowanceForCreditLossesPolicyForUncollectibleAmounts	<div style="margin-bottom:6pt;margin-top:6pt;text-align:justify"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%;text-decoration:underline">Allowance for Credit Losses - Loans</span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">. With the adoption of ASU 2016-13 on January 1, 2020, the allowance for credit losses on loans is estimated and recognized upon origination of the loan based on expected credit losses. ASU 2016-13 replaced the previous incurred loss model which incorporated only known information as of the balance sheet date. The CECL model uses historical experience and current conditions for homogeneous pools of loans, and reasonable and supportable forecasts about future events. We utilize Moody’s Analytics economic forecast scenarios and assign probability weighting to those scenarios which best reflect management’s views on the economic forecast. The probability weighting and scenarios utilized for the third quarter 2020 estimate of the allowance, were generally reflective of an improved economic forecast as compared to prior quarters. </span></div><div style="margin-bottom:6pt;margin-top:6pt;text-align:justify"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">When determining the appropriate allowance for credit losses on our loan portfolio, our commercial construction and real estate loans, commercial loans and municipal loans utilize the probability of default/loss given default discounted cash flow approach. These loans are assigned to pools based upon risk factors including the loan type and structure, collateral type, leverage ratio, refinancing risk and origination quality, among others. Our consumer construction real estate loans, 1-4 family residential loans and our loans to individuals use a loss rate approach and are assigned to pools based upon risk factors including loan types, origination year and credit scores. </span></div>Loans evaluated collectively in a pool are monitored to ensure they continue to exhibit similar risk characteristics with other loans in a pool. If a loan does not share similar risk characteristics with other loans, expected credit losses for that loan are evaluated individually.
CY2020Q3	us-gaap	Net Income Loss NetIncomeLoss	27074000	USD
CY2019Q3	us-gaap	Net Income Loss NetIncomeLoss	19792000	USD
	us-gaap	Net Income Loss NetIncomeLoss	52581000	USD
	us-gaap	Net Income Loss NetIncomeLoss	57219000	USD
CY2020Q3	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	33047000	shares
CY2019Q3	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	33773000	shares
	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	33250000	shares
	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	33732000	shares
CY2020Q3	us-gaap	Incremental Common Shares Attributable To Share Based Payment Arrangements IncrementalCommonSharesAttributableToShareBasedPaymentArrangements	51000	shares
CY2019Q3	us-gaap	Incremental Common Shares Attributable To Share Based Payment Arrangements IncrementalCommonSharesAttributableToShareBasedPaymentArrangements	128000	shares
	us-gaap	Incremental Common Shares Attributable To Share Based Payment Arrangements IncrementalCommonSharesAttributableToShareBasedPaymentArrangements	81000	shares
	us-gaap	Incremental Common Shares Attributable To Share Based Payment Arrangements IncrementalCommonSharesAttributableToShareBasedPaymentArrangements	146000	shares
CY2020Q3	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	33098000	shares
CY2019Q3	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	33901000	shares
	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	33331000	shares
	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	33878000	shares
CY2020Q3	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.82
CY2019Q3	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.59
	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	1.58
	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	1.70
CY2020Q3	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.82
CY2019Q3	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.58
	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	1.58
	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	1.69
CY2020Q3	us-gaap	Antidilutive Securities Excluded From Computation Of Earnings Per Share Amount AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount	835000	shares
	us-gaap	Antidilutive Securities Excluded From Computation Of Earnings Per Share Amount AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount	811000	shares
CY2019Q3	us-gaap	Antidilutive Securities Excluded From Computation Of Earnings Per Share Amount AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount	477000	shares
	us-gaap	Antidilutive Securities Excluded From Computation Of Earnings Per Share Amount AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount	482000	shares
CY2020Q3	us-gaap	Reclassification From Accumulated Other Comprehensive Income Current Period Net Of Tax ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodNetOfTax	-2150000	USD
CY2019Q3	us-gaap	Reclassification From Accumulated Other Comprehensive Income Current Period Net Of Tax ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodNetOfTax	-132000	USD
	us-gaap	Reclassification From Accumulated Other Comprehensive Income Current Period Net Of Tax ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodNetOfTax	2418000	USD
	us-gaap	Reclassification From Accumulated Other Comprehensive Income Current Period Net Of Tax ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodNetOfTax	44000	USD
CY2020Q3	us-gaap	Available For Sale Debt Securities Amortized Cost Basis AvailableForSaleDebtSecuritiesAmortizedCostBasis	2500696000	USD
CY2020Q3	us-gaap	Available For Sale Debt Securities Accumulated Gross Unrealized Gain Before Tax AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedGainBeforeTax	133296000	USD
CY2020Q3	us-gaap	Available For Sale Debt Securities Accumulated Gross Unrealized Loss Before Tax AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedLossBeforeTax	473000	USD
CY2020Q3	us-gaap	Available For Sale Securities Debt Securities AvailableForSaleSecuritiesDebtSecurities	2633519000	USD
CY2020Q3	sbsi	Debt Securities Heldto Maturity Netof Allowancefor Credit Losses DebtSecuritiesHeldtoMaturityNetofAllowanceforCreditLosses	115089000	USD
CY2020Q3	us-gaap	Held To Maturity Securities Accumulated Unrecognized Holding Gain HeldToMaturitySecuritiesAccumulatedUnrecognizedHoldingGain	10292000	USD
CY2020Q3	us-gaap	Held To Maturity Securities Accumulated Unrecognized Holding Loss HeldToMaturitySecuritiesAccumulatedUnrecognizedHoldingLoss	0	USD
CY2020Q3	us-gaap	Held To Maturity Securities Fair Value HeldToMaturitySecuritiesFairValue	125381000	USD
CY2019Q4	us-gaap	Available For Sale Debt Securities Amortized Cost Basis AvailableForSaleDebtSecuritiesAmortizedCostBasis	2306741000	USD
CY2019Q4	us-gaap	Available For Sale Debt Securities Accumulated Gross Unrealized Gain Before Tax AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedGainBeforeTax	54426000	USD
CY2019Q4	us-gaap	Available For Sale Debt Securities Accumulated Gross Unrealized Loss Before Tax AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedLossBeforeTax	2570000	USD
CY2019Q4	us-gaap	Available For Sale Securities Debt Securities AvailableForSaleSecuritiesDebtSecurities	2358597000	USD
CY2019Q4	us-gaap	Held To Maturity Securities HeldToMaturitySecurities	134863000	USD
CY2019Q4	us-gaap	Held To Maturity Securities Accumulated Unrecognized Holding Gain HeldToMaturitySecuritiesAccumulatedUnrecognizedHoldingGain	4238000	USD
CY2019Q4	us-gaap	Held To Maturity Securities Accumulated Unrecognized Holding Loss HeldToMaturitySecuritiesAccumulatedUnrecognizedHoldingLoss	222000	USD
CY2019Q4	us-gaap	Held To Maturity Securities Fair Value HeldToMaturitySecuritiesFairValue	138879000	USD
CY2020Q3	us-gaap	Pledged Financial Instruments Not Separately Reported Securities Pledged PledgedFinancialInstrumentsNotSeparatelyReportedSecuritiesPledged	1510000000	USD
CY2019Q4	us-gaap	Pledged Financial Instruments Not Separately Reported Securities Pledged PledgedFinancialInstrumentsNotSeparatelyReportedSecuritiesPledged	1120000000	USD
CY2020Q3	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position Less Than12 Months DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12Months	53443000	USD
CY2020Q3	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position Less Than12 Months Accumulated Loss DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss	473000	USD
CY2020Q3	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position12 Months Or Longer DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLonger	0	USD
CY2020Q3	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position12 Months Or Longer Accumulated Loss DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLongerAccumulatedLoss	0	USD
CY2020Q3	us-gaap	Debt Securities Available For Sale Unrealized Loss Position DebtSecuritiesAvailableForSaleUnrealizedLossPosition	53443000	USD
CY2020Q3	us-gaap	Debt Securities Available For Sale Unrealized Loss Position Accumulated Loss DebtSecuritiesAvailableForSaleUnrealizedLossPositionAccumulatedLoss	473000	USD
CY2019Q4	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position Less Than12 Months DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12Months	273963000	USD
CY2019Q4	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position Less Than12 Months Accumulated Loss DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss	2282000	USD
CY2019Q4	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position12 Months Or Longer DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLonger	30697000	USD
CY2019Q4	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position12 Months Or Longer Accumulated Loss DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLongerAccumulatedLoss	288000	USD
CY2019Q4	us-gaap	Debt Securities Available For Sale Unrealized Loss Position DebtSecuritiesAvailableForSaleUnrealizedLossPosition	304660000	USD
CY2019Q4	us-gaap	Debt Securities Available For Sale Unrealized Loss Position Accumulated Loss DebtSecuritiesAvailableForSaleUnrealizedLossPositionAccumulatedLoss	2570000	USD
CY2020Q3	us-gaap	Debt Securities Available For Sale Allowance For Credit Loss DebtSecuritiesAvailableForSaleAllowanceForCreditLoss	0	USD
CY2019Q4	us-gaap	Held To Maturity Securities Continuous Unrealized Loss Position Less Than Twelve Months Fair Value HeldToMaturitySecuritiesContinuousUnrealizedLossPositionLessThanTwelveMonthsFairValue	13053000	USD
CY2019Q4	us-gaap	Held To Maturity Securities Continuous Unrealized Loss Position Less Than12 Months Accumulated Loss HeldToMaturitySecuritiesContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss	76000	USD
CY2019Q4	us-gaap	Held To Maturity Securities Continuous Unrealized Loss Position Twelve Months Or Longer Fair Value HeldToMaturitySecuritiesContinuousUnrealizedLossPositionTwelveMonthsOrLongerFairValue	4092000	USD
CY2019Q4	us-gaap	Held To Maturity Securities Continuous Unrealized Loss Position12 Months Or Longer Accumulated Loss HeldToMaturitySecuritiesContinuousUnrealizedLossPosition12MonthsOrLongerAccumulatedLoss	146000	USD
CY2019Q4	us-gaap	Held To Maturity Securities Continuous Unrealized Loss Position Fair Value HeldToMaturitySecuritiesContinuousUnrealizedLossPositionFairValue	17145000	USD
CY2019Q4	us-gaap	Held To Maturity Securities Continuous Unrealized Loss Position Accumulated Loss HeldToMaturitySecuritiesContinuousUnrealizedLossPositionAccumulatedLoss	222000	USD
	us-gaap	Debt Securities Available For Sale Allowance For Credit Loss Period Increase Decrease DebtSecuritiesAvailableForSaleAllowanceForCreditLossPeriodIncreaseDecrease	0	USD
	us-gaap	Debt Securities Held To Maturity Credit Loss Expense Reversal DebtSecuritiesHeldToMaturityCreditLossExpenseReversal	0	USD
CY2020Q3	us-gaap	Debt Securities Held To Maturity Credit Loss Expense Reversal DebtSecuritiesHeldToMaturityCreditLossExpenseReversal	0	USD
CY2020Q3	us-gaap	Debt Securities Held To Maturity Allowance For Credit Loss DebtSecuritiesHeldToMaturityAllowanceForCreditLoss	0	USD
CY2020Q3	sbsi	Transferred Securities Unrealized Loss Before Tax TransferredSecuritiesUnrealizedLossBeforeTax	3300000	USD
CY2020Q3	sbsi	Securities Transferred Unrealized Loss Net Of Tax SecuritiesTransferredUnrealizedLossNetOfTax	2600000	USD
CY2019Q4	sbsi	Transferred Securities Unrealized Loss Before Tax TransferredSecuritiesUnrealizedLossBeforeTax	3700000	USD
CY2019Q4	sbsi	Securities Transferred Unrealized Loss Net Of Tax SecuritiesTransferredUnrealizedLossNetOfTax	2900000	USD
CY2019	sbsi	Securities Transferred From Available For Sale To Held To Maturity SecuritiesTransferredFromAvailableForSaleToHeldToMaturity	0	USD
	sbsi	Securities Transferred From Available For Sale To Held To Maturity SecuritiesTransferredFromAvailableForSaleToHeldToMaturity	0	USD
CY2020Q3	us-gaap	Debt Securities Held To Maturity Past Due DebtSecuritiesHeldToMaturityPastDue	0	USD
CY2020Q3	us-gaap	Debt Securities Held To Maturity Nonaccrual DebtSecuritiesHeldToMaturityNonaccrual	0	USD
CY2020Q3	us-gaap	Interest Income Securities State And Municipal InterestIncomeSecuritiesStateAndMunicipal	9787000	USD
CY2019Q3	us-gaap	Interest Income Securities State And Municipal InterestIncomeSecuritiesStateAndMunicipal	4167000	USD
CY2020Q3	sbsi	Interest Income Other Stocks And Bonds InterestIncomeOtherStocksAndBonds	391000	USD
CY2019Q3	sbsi	Interest Income Other Stocks And Bonds InterestIncomeOtherStocksAndBonds	26000	USD
CY2020Q3	us-gaap	Interest Income Securities Mortgage Backed InterestIncomeSecuritiesMortgageBacked	7048000	USD
CY2019Q3	us-gaap	Interest Income Securities Mortgage Backed InterestIncomeSecuritiesMortgageBacked	12569000	USD
CY2020Q3	us-gaap	Interest And Other Income InterestAndOtherIncome	17226000	USD
CY2019Q3	us-gaap	Interest And Other Income InterestAndOtherIncome	16762000	USD
	us-gaap	Interest Income Securities State And Municipal InterestIncomeSecuritiesStateAndMunicipal	26281000	USD
	us-gaap	Interest Income Securities State And Municipal InterestIncomeSecuritiesStateAndMunicipal	11812000	USD
	sbsi	Interest Income Other Stocks And Bonds InterestIncomeOtherStocksAndBonds	568000	USD
	sbsi	Interest Income Other Stocks And Bonds InterestIncomeOtherStocksAndBonds	81000	USD
	us-gaap	Interest Income Securities Mortgage Backed InterestIncomeSecuritiesMortgageBacked	27626000	USD
	us-gaap	Interest Income Securities Mortgage Backed InterestIncomeSecuritiesMortgageBacked	38289000	USD
	us-gaap	Interest And Other Income InterestAndOtherIncome	54475000	USD
	us-gaap	Interest And Other Income InterestAndOtherIncome	50182000	USD
	us-gaap	Debt Securities Available For Sale Realized Gain Loss DebtSecuritiesAvailableForSaleRealizedGainLoss	8300000	USD
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CY2019Q4	sbsi	Unsettled Issuancesof Brokered C Ds UnsettledIssuancesofBrokeredCDs	20000000.0	USD

Files In Submission

Name	View Source	Status
0000705432-20-000169-index-headers.html	Edgar Link	pending
0000705432-20-000169-index.html	Edgar Link	pending
0000705432-20-000169.txt	Edgar Link	pending
0000705432-20-000169-xbrl.zip	Edgar Link	pending
FilingSummary.xml	Edgar Link	unprocessable
Financial_Report.xlsx	Edgar Link	pending
MetaLinks.json	Edgar Link	pending
R1.htm	Edgar Link	pending
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report.css	Edgar Link	pending
sbsi-20200930.htm	Edgar Link	pending
sbsi-20200930.xsd	Edgar Link	pending
sbsi-20200930_cal.xml	Edgar Link	unprocessable
sbsi-20200930_def.xml	Edgar Link	unprocessable
sbsi-20200930_htm.xml	Edgar Link	completed
sbsi-20200930_lab.xml	Edgar Link	unprocessable
sbsi-20200930_pre.xml	Edgar Link	unprocessable
sbsi093020ex311.htm	Edgar Link	pending
sbsi093020ex312.htm	Edgar Link	pending
sbsi093020ex32.htm	Edgar Link	pending
Show.js	Edgar Link	pending

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$SBSI
SOUTHSIDE BANCSHARES INC Stock $sbsi

2020 Q4 Form 10-Q Financial Statement

#000070543220000169 Filed on October 30, 2020

Income Statement

Balance Sheet

Cashflow Statement

Facts In Submission

Files In Submission

$SBSI SOUTHSIDE BANCSHARES INC Stock $sbsi

2020 Q4 Form 10-Q Financial Statement

#000070543220000169 Filed on October 30, 2020

Income Statement

Balance Sheet

Cashflow Statement

Facts In Submission

Files In Submission

$SBSI
SOUTHSIDE BANCSHARES INC Stock $sbsi