$SFNC
Simmons First National Corp Stock $sfnc

$sfnc Overview Financials Valuation SEC Filings Company Website

2020 Q4 Form 10-K Financial Statement

#000162828021003318 Filed on February 25, 2021

Income Statement

Concept	2020 Q4	2020	2019 Q4
Revenue		$759.7M
YoY Change		-2.99%
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	$12.40M	$49.04M	$10.80M
YoY Change	14.81%	35.25%	42.11%
% of Gross Profit
Operating Expenses
YoY Change
Operating Profit
YoY Change
Interest Expense		$120.0M
YoY Change		-33.85%
% of Operating Profit
Other Income/Expense, Net
YoY Change
Pretax Income	$63.90M	$319.8M	$65.70M
YoY Change	-2.74%	5.75%	-2.52%
Income Tax	$11.00M	$64.89M	$13.00M
% Of Pretax Income	17.21%	20.29%	19.79%
Net Earnings	$53.00M	$254.9M	$52.70M
YoY Change	0.57%	7.03%	-5.22%
Net Earnings / Revenue		33.55%
Basic Earnings Per Share		$2.32
Diluted Earnings Per Share	$485.3K	$2.31	$484.4K
COMMON SHARES
Basic Shares Outstanding	108.8M shares	109.9M shares	96.65M shares
Diluted Shares Outstanding		110.2M shares

Balance Sheet

Concept	2020 Q4	2020	2019 Q4
SHORT-TERM ASSETS
Cash & Short-Term Investments
YoY Change
Cash & Equivalents	$3.472B		$996.6M
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	$442.0M	$442.0M	$492.4M
YoY Change	-10.23%	-10.16%	66.88%
Goodwill	$1.080B		$1.060B
YoY Change	1.89%		25.34%
Intangibles
YoY Change
Long-Term Investments
YoY Change
Other Assets	$29.00M	$29.00M	$250.0M
YoY Change	-88.4%	-88.4%	1566.67%
Total Long-Term Assets
YoY Change
TOTAL ASSETS
Total Short-Term Assets
Total Long-Term Assets
Total Assets	$22.36B	$22.36B	$21.26B
YoY Change	5.18%	5.18%	28.51%
SHORT-TERM LIABILITIES
YoY Change
Accounts Payable	$186.0M	$186.0M	$125.0M
YoY Change	48.8%	48.8%	21.36%
Accrued Expenses	$31.00M	$31.00M	$41.00M
YoY Change	-24.39%	-24.39%
Deferred Revenue
YoY Change
Short-Term Debt	$299.0M	$299.0M	$150.0M
YoY Change	99.33%	99.33%	56.25%
Long-Term Debt Due
YoY Change
Total Short-Term Liabilities	$217.0M	$217.0M	$166.0M
YoY Change	30.72%	30.72%	61.17%
LONG-TERM LIABILITIES
Long-Term Debt	$1.725B	$416.0M	$435.9M
YoY Change	295.76%	-1.65%	17.99%
Other Long-Term Liabilities	$155.0M	$155.0M	$160.0M
YoY Change	-3.13%	-3.13%
Total Long-Term Liabilities	$1.725B	$571.0M	$435.9M
YoY Change	295.76%	-2.06%	17.99%
TOTAL LIABILITIES
Total Short-Term Liabilities	$217.0M	$217.0M	$166.0M
Total Long-Term Liabilities	$1.725B	$571.0M	$435.9M
Total Liabilities	$19.38B	$19.38B	$18.27B
YoY Change	6.09%	6.09%	27.79%
SHAREHOLDERS EQUITY
Retained Earnings	$901.0M		$848.8M
YoY Change	6.14%		25.77%
Common Stock	$1.081M		$1.136M
YoY Change	-4.84%		23.08%
Preferred Stock
YoY Change
Treasury Stock (at cost)
YoY Change
Treasury Stock Shares
Shareholders Equity	$2.977B	$2.977B	$2.989B
YoY Change
Total Liabilities & Shareholders Equity	$22.36B	$22.36B	$21.26B
YoY Change	5.18%	5.18%	28.51%

Cashflow Statement

Concept	2020 Q4	2020	2019 Q4
OPERATING ACTIVITIES
Net Income	$53.00M	$254.9M	$52.70M
YoY Change	0.57%	7.03%	-5.22%
Depreciation, Depletion And Amortization	$12.40M	$49.04M	$10.80M
YoY Change	14.81%	35.25%	42.11%
Cash From Operating Activities	$126.1M	$202.5M	$58.20M
YoY Change	116.67%	-20.91%	-22.3%
INVESTING ACTIVITIES
Capital Expenditures	$9.400M	$13.27M	-$30.30M
YoY Change	-131.02%	-80.43%	140.48%
Acquisitions		$0.00
YoY Change		-100.0%
Other Investing Activities	-$26.10M	$1.203B	$492.2M
YoY Change	-105.3%	78.95%	607.18%
Cash From Investing Activities	-$16.60M	$1.190B	$462.0M
YoY Change	-103.59%	96.84%	710.53%
FINANCING ACTIVITIES
Cash Dividend Paid
YoY Change
Common Stock Issuance & Retirement, Net		$113.3M
YoY Change		1018.95%
Debt Paid & Issued, Net
YoY Change
Cash From Financing Activities	840.5M	$1.083B	-53.50M
YoY Change	-1671.03%	-255.31%	-128.47%
NET CHANGE
Cash From Operating Activities	126.1M	$202.5M	58.20M
Cash From Investing Activities	-16.60M	$1.190B	462.0M
Cash From Financing Activities	840.5M	$1.083B	-53.50M
Net Change In Cash	950.0M	$2.476B	466.7M
YoY Change	103.56%	1417.19%	45.93%
FREE CASH FLOW
Cash From Operating Activities	$126.1M	$202.5M	$58.20M
Capital Expenditures	$9.400M	$13.27M	-$30.30M
Free Cash Flow	$116.7M	$189.3M	$88.50M
YoY Change	31.86%	0.54%	1.14%

Facts In Submission

Frame	Concept Type	Concept / XBRL Key	Value	Unit
CY2020	dei	Entity Central Index Key EntityCentralIndexKey	0000090498
CY2020	dei	Document Fiscal Year Focus DocumentFiscalYearFocus	2020
CY2020	dei	Document Fiscal Period Focus DocumentFiscalPeriodFocus	FY
CY2020	dei	Amendment Flag AmendmentFlag	false
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CY2020	dei	Document Type DocumentType	10-K
CY2020	dei	Document Annual Report DocumentAnnualReport	true
CY2020	dei	Document Period End Date DocumentPeriodEndDate	2020-12-31
CY2020	dei	Current Fiscal Year End Date CurrentFiscalYearEndDate	--12-31
CY2020	dei	Document Transition Report DocumentTransitionReport	false
CY2020	dei	Entity File Number EntityFileNumber	000-06253
CY2020	dei	Entity Registrant Name EntityRegistrantName	SIMMONS FIRST NATIONAL CORP
CY2020	dei	Entity Incorporation State Country Code EntityIncorporationStateCountryCode	AR
CY2020	dei	Entity Tax Identification Number EntityTaxIdentificationNumber	71-0407808
CY2020	dei	Entity Address Address Line1 EntityAddressAddressLine1	501 Main Street
CY2020	dei	Entity Address Postal Zip Code EntityAddressPostalZipCode	71601
CY2020	dei	Entity Address City Or Town EntityAddressCityOrTown	Pine Bluff
CY2020	dei	Entity Address State Or Province EntityAddressStateOrProvince	AR
CY2020	dei	City Area Code CityAreaCode	870
CY2020	dei	Local Phone Number LocalPhoneNumber	541-1000
CY2020	dei	Security12b Title Security12bTitle	Common stock, par value $0.01 per share
CY2020	dei	Trading Symbol TradingSymbol	SFNC
CY2020	dei	Security Exchange Name SecurityExchangeName	NASDAQ
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CY2020	dei	Entity Voluntary Filers EntityVoluntaryFilers	No
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CY2020	us-gaap	Debt And Equity Securities Gain Loss DebtAndEquitySecuritiesGainLoss	54806000	USD
CY2018	us-gaap	Equipment Expense EquipmentExpense	16323000	USD
CY2020	us-gaap	Foreclosed Real Estate Expense ForeclosedRealEstateExpense	1752000	USD
CY2019	us-gaap	Foreclosed Real Estate Expense ForeclosedRealEstateExpense	3442000	USD
CY2019	us-gaap	Debt And Equity Securities Gain Loss DebtAndEquitySecuritiesGainLoss	13314000	USD
CY2018	us-gaap	Debt And Equity Securities Gain Loss DebtAndEquitySecuritiesGainLoss	61000	USD
CY2020	us-gaap	Noninterest Income Other Operating Income NoninterestIncomeOtherOperatingIncome	38547000	USD
CY2019	us-gaap	Noninterest Income Other Operating Income NoninterestIncomeOtherOperatingIncome	62015000	USD
CY2018	us-gaap	Noninterest Income Other Operating Income NoninterestIncomeOtherOperatingIncome	23721000	USD
CY2020	us-gaap	Noninterest Income NoninterestIncome	248528000	USD
CY2019	us-gaap	Noninterest Income NoninterestIncome	205031000	USD
CY2018	us-gaap	Noninterest Income NoninterestIncome	147754000	USD
CY2020	us-gaap	Labor And Related Expense LaborAndRelatedExpense	242474000	USD
CY2019	us-gaap	Labor And Related Expense LaborAndRelatedExpense	227795000	USD
CY2018	us-gaap	Labor And Related Expense LaborAndRelatedExpense	216743000	USD
CY2020	us-gaap	Equipment Expense EquipmentExpense	24038000	USD
CY2019	us-gaap	Equipment Expense EquipmentExpense	18220000	USD
CY2018	us-gaap	Foreclosed Real Estate Expense ForeclosedRealEstateExpense	4480000	USD
CY2020	us-gaap	Federal Deposit Insurance Corporation Premium Expense FederalDepositInsuranceCorporationPremiumExpense	9184000	USD
CY2019	us-gaap	Income Loss Attributable To Parent IncomeLossAttributableToParent	302432000	USD
CY2019	us-gaap	Federal Deposit Insurance Corporation Premium Expense FederalDepositInsuranceCorporationPremiumExpense	4416000	USD
CY2018	us-gaap	Federal Deposit Insurance Corporation Premium Expense FederalDepositInsuranceCorporationPremiumExpense	8721000	USD
CY2020	us-gaap	Acquisition Costs AcquisitionCosts	4531000	USD
CY2019	us-gaap	Acquisition Costs AcquisitionCosts	36379000	USD
CY2018	us-gaap	Acquisition Costs AcquisitionCosts	4777000	USD
CY2020	us-gaap	Other Noninterest Expense OtherNoninterestExpense	173960000	USD
CY2019	us-gaap	Other Noninterest Expense OtherNoninterestExpense	138852000	USD
CY2018	us-gaap	Other Noninterest Expense OtherNoninterestExpense	111575000	USD
CY2020	us-gaap	Noninterest Expense NoninterestExpense	493495000	USD
CY2019	us-gaap	Noninterest Expense NoninterestExpense	461112000	USD
CY2018	us-gaap	Noninterest Expense NoninterestExpense	392229000	USD
CY2020	us-gaap	Income Loss Attributable To Parent IncomeLossAttributableToParent	319794000	USD
CY2018	us-gaap	Income Loss Attributable To Parent IncomeLossAttributableToParent	266071000	USD
CY2020	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	64890000	USD
CY2019	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	64265000	USD
CY2018	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	50358000	USD
CY2020	us-gaap	Net Income Loss NetIncomeLoss	254904000	USD
CY2019	us-gaap	Net Income Loss NetIncomeLoss	238167000	USD
CY2018	us-gaap	Net Income Loss NetIncomeLoss	215713000	USD
CY2020	us-gaap	Preferred Stock Dividends Income Statement Impact PreferredStockDividendsIncomeStatementImpact	52000	USD
CY2019	us-gaap	Preferred Stock Dividends Income Statement Impact PreferredStockDividendsIncomeStatementImpact	339000	USD
CY2018	us-gaap	Preferred Stock Dividends Income Statement Impact PreferredStockDividendsIncomeStatementImpact	0	USD
CY2020	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	254852000	USD
CY2019	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	237828000	USD
CY2018	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	215713000	USD
CY2020	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	2.32
CY2019	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	2.42
CY2018	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	2.34
CY2020	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	2.31
CY2019	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	2.41
CY2018	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	2.32
CY2020	us-gaap	Net Income Loss NetIncomeLoss	254904000	USD
CY2019	us-gaap	Net Income Loss NetIncomeLoss	238167000	USD
CY2018	us-gaap	Net Income Loss NetIncomeLoss	215713000	USD
CY2020	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Before Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodBeforeTax	107382000	USD
CY2019	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Before Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodBeforeTax	76109000	USD
CY2018	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Before Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodBeforeTax	-13626000	USD
CY2020	us-gaap	Other Comprehensive Income Reclassification Adjustment For Held To Maturity Transferred To Available For Sale Securities Before Tax OtherComprehensiveIncomeReclassificationAdjustmentForHeldToMaturityTransferredToAvailableForSaleSecuritiesBeforeTax	0	USD
CY2019	us-gaap	Other Comprehensive Income Reclassification Adjustment For Held To Maturity Transferred To Available For Sale Securities Before Tax OtherComprehensiveIncomeReclassificationAdjustmentForHeldToMaturityTransferredToAvailableForSaleSecuritiesBeforeTax	2547000	USD
CY2018	us-gaap	Other Comprehensive Income Reclassification Adjustment For Held To Maturity Transferred To Available For Sale Securities Before Tax OtherComprehensiveIncomeReclassificationAdjustmentForHeldToMaturityTransferredToAvailableForSaleSecuritiesBeforeTax	0	USD
CY2020	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci For Sale Of Securities Net Of Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesNetOfTax	54806000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci For Sale Of Securities Net Of Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesNetOfTax	13314000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci For Sale Of Securities Net Of Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesNetOfTax	61000	USD
CY2020	us-gaap	Other Comprehensive Income Loss Before Tax Portion Attributable To Parent OtherComprehensiveIncomeLossBeforeTaxPortionAttributableToParent	52576000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Before Tax Portion Attributable To Parent OtherComprehensiveIncomeLossBeforeTaxPortionAttributableToParent	65342000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Before Tax Portion Attributable To Parent OtherComprehensiveIncomeLossBeforeTaxPortionAttributableToParent	-13687000	USD
CY2020	us-gaap	Other Comprehensive Income Loss Tax OtherComprehensiveIncomeLossTax	13741000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Tax OtherComprehensiveIncomeLossTax	17077000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Tax OtherComprehensiveIncomeLossTax	-3577000	USD
CY2020	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	38835000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	48265000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	-10110000	USD
CY2020	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	293739000	USD
CY2019	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	286432000	USD
CY2018	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	205603000	USD
CY2020	us-gaap	Net Income Loss NetIncomeLoss	254904000	USD
CY2019	us-gaap	Net Income Loss NetIncomeLoss	238167000	USD
CY2018	us-gaap	Net Income Loss NetIncomeLoss	215713000	USD
CY2020	us-gaap	Depreciation Depletion And Amortization DepreciationDepletionAndAmortization	49038000	USD
CY2019	us-gaap	Depreciation Depletion And Amortization DepreciationDepletionAndAmortization	36257000	USD
CY2018	us-gaap	Depreciation Depletion And Amortization DepreciationDepletionAndAmortization	28412000	USD
CY2020	us-gaap	Provision For Loan Lease And Other Losses ProvisionForLoanLeaseAndOtherLosses	74973000	USD
CY2019	us-gaap	Provision For Loan Lease And Other Losses ProvisionForLoanLeaseAndOtherLosses	43240000	USD
CY2018	us-gaap	Provision For Loan Lease And Other Losses ProvisionForLoanLeaseAndOtherLosses	38148000	USD
CY2020	us-gaap	Gain Loss On Sale Of Investments GainLossOnSaleOfInvestments	54806000	USD
CY2019	us-gaap	Gain Loss On Sale Of Investments GainLossOnSaleOfInvestments	13314000	USD
CY2018	us-gaap	Gain Loss On Sale Of Investments GainLossOnSaleOfInvestments	61000	USD
CY2020	us-gaap	Accretion Amortization Of Discounts And Premiums Investments AccretionAmortizationOfDiscountsAndPremiumsInvestments	56771000	USD
CY2019	us-gaap	Accretion Amortization Of Discounts And Premiums Investments AccretionAmortizationOfDiscountsAndPremiumsInvestments	53619000	USD
CY2018	us-gaap	Accretion Amortization Of Discounts And Premiums Investments AccretionAmortizationOfDiscountsAndPremiumsInvestments	48684000	USD
CY2020	sfnc	Amortization Accretion Of Debt Issuance Costs And Discounts AmortizationAccretionOfDebtIssuanceCostsAndDiscounts	541000	USD
CY2019	sfnc	Amortization Accretion Of Debt Issuance Costs And Discounts AmortizationAccretionOfDebtIssuanceCostsAndDiscounts	394000	USD
CY2018	sfnc	Amortization Accretion Of Debt Issuance Costs And Discounts AmortizationAccretionOfDebtIssuanceCostsAndDiscounts	-380000	USD
CY2020	us-gaap	Share Based Compensation ShareBasedCompensation	13197000	USD
CY2019	us-gaap	Share Based Compensation ShareBasedCompensation	12921000	USD
CY2018	us-gaap	Share Based Compensation ShareBasedCompensation	9725000	USD
CY2020	us-gaap	Gain Loss On Sale Of Property Plant Equipment GainLossOnSaleOfPropertyPlantEquipment	14000	USD
CY2019	us-gaap	Gain Loss On Sale Of Property Plant Equipment GainLossOnSaleOfPropertyPlantEquipment	0	USD
CY2018	us-gaap	Gain Loss On Sale Of Property Plant Equipment GainLossOnSaleOfPropertyPlantEquipment	0	USD
CY2020	us-gaap	Gains Losses On Sales Of Other Real Estate GainsLossesOnSalesOfOtherRealEstate	391000	USD
CY2019	us-gaap	Gains Losses On Sales Of Other Real Estate GainsLossesOnSalesOfOtherRealEstate	33000	USD
CY2018	us-gaap	Gains Losses On Sales Of Other Real Estate GainsLossesOnSalesOfOtherRealEstate	650000	USD
CY2020	us-gaap	Gain Loss On Sale Of Mortgage Loans GainLossOnSaleOfMortgageLoans	44864000	USD
CY2019	us-gaap	Gain Loss On Sale Of Mortgage Loans GainLossOnSaleOfMortgageLoans	20064000	USD
CY2018	us-gaap	Gain Loss On Sale Of Mortgage Loans GainLossOnSaleOfMortgageLoans	12844000	USD
CY2020	us-gaap	Gain Loss On Disposition Of Intangible Assets GainLossOnDispositionOfIntangibleAssets	301000	USD
CY2019	us-gaap	Gain Loss On Disposition Of Intangible Assets GainLossOnDispositionOfIntangibleAssets	0	USD
CY2018	us-gaap	Gain Loss On Disposition Of Intangible Assets GainLossOnDispositionOfIntangibleAssets	0	USD
CY2020	us-gaap	Disposal Group Not Discontinued Operation Gain Loss On Disposal DisposalGroupNotDiscontinuedOperationGainLossOnDisposal	8094000	USD
CY2019	us-gaap	Disposal Group Not Discontinued Operation Gain Loss On Disposal DisposalGroupNotDiscontinuedOperationGainLossOnDisposal	0	USD
CY2018	us-gaap	Disposal Group Not Discontinued Operation Gain Loss On Disposal DisposalGroupNotDiscontinuedOperationGainLossOnDisposal	0	USD
CY2020	us-gaap	Gain Loss On Sales Of Consumer Loans GainLossOnSalesOfConsumerLoans	0	USD
CY2019	us-gaap	Gain Loss On Sales Of Consumer Loans GainLossOnSalesOfConsumerLoans	-4451000	USD
CY2018	us-gaap	Gain Loss On Sales Of Consumer Loans GainLossOnSalesOfConsumerLoans	10000	USD
CY2020	us-gaap	Gain Loss On Sale Of Previously Unissued Stock By Subsidiary Or Equity Investee Nonoperating Income GainLossOnSaleOfPreviouslyUnissuedStockBySubsidiaryOrEquityInvesteeNonoperatingIncome	0	USD
CY2019	us-gaap	Gain Loss On Sale Of Previously Unissued Stock By Subsidiary Or Equity Investee Nonoperating Income GainLossOnSaleOfPreviouslyUnissuedStockBySubsidiaryOrEquityInvesteeNonoperatingIncome	42860000	USD
CY2020	us-gaap	Impairment Of Long Lived Assets To Be Disposed Of ImpairmentOfLongLivedAssetsToBeDisposedOf	434000	USD
CY2019	us-gaap	Impairment Of Long Lived Assets To Be Disposed Of ImpairmentOfLongLivedAssetsToBeDisposedOf	0	USD
CY2018	us-gaap	Impairment Of Long Lived Assets To Be Disposed Of ImpairmentOfLongLivedAssetsToBeDisposedOf	836000	USD
CY2020	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	-122000	USD
CY2019	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	34911000	USD
CY2018	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	8412000	USD
CY2020	sfnc	Bank Owned Life Insuranceand Death Benefits Income BankOwnedLifeInsuranceandDeathBenefitsIncome	7206000	USD
CY2019	sfnc	Bank Owned Life Insuranceand Death Benefits Income BankOwnedLifeInsuranceandDeathBenefitsIncome	4854000	USD
CY2018	sfnc	Bank Owned Life Insuranceand Death Benefits Income BankOwnedLifeInsuranceandDeathBenefitsIncome	5003000	USD
CY2020	us-gaap	Payments For Origination Of Mortgage Loans Held For Sale PaymentsForOriginationOfMortgageLoansHeldForSale	1206818000	USD
CY2019	us-gaap	Payments For Origination Of Mortgage Loans Held For Sale PaymentsForOriginationOfMortgageLoansHeldForSale	755500000	USD
CY2018	us-gaap	Payments For Origination Of Mortgage Loans Held For Sale PaymentsForOriginationOfMortgageLoansHeldForSale	546676000	USD
CY2020	us-gaap	Proceeds From Sale Of Mortgage Loans Held For Sale ProceedsFromSaleOfMortgageLoansHeldForSale	1172406000	USD
CY2019	us-gaap	Proceeds From Sale Of Mortgage Loans Held For Sale ProceedsFromSaleOfMortgageLoansHeldForSale	756642000	USD
CY2018	us-gaap	Proceeds From Sale Of Mortgage Loans Held For Sale ProceedsFromSaleOfMortgageLoansHeldForSale	556759000	USD
CY2020	us-gaap	Increase Decrease In Accrued Interest Receivable Net IncreaseDecreaseInAccruedInterestReceivableNet	10846000	USD
CY2018	sfnc	Proceeds From Loan Originations And Principal Collections Net ProceedsFromLoanOriginationsAndPrincipalCollectionsNet	912793000	USD
CY2019	us-gaap	Increase Decrease In Accrued Interest Receivable Net IncreaseDecreaseInAccruedInterestReceivableNet	-3231000	USD
CY2019	us-gaap	Increase Decrease In Accrued Income Taxes Payable IncreaseDecreaseInAccruedIncomeTaxesPayable	20074000	USD
CY2018	us-gaap	Increase Decrease In Accrued Income Taxes Payable IncreaseDecreaseInAccruedIncomeTaxesPayable	-9355000	USD
CY2018	us-gaap	Increase Decrease In Accrued Interest Receivable Net IncreaseDecreaseInAccruedInterestReceivableNet	6227000	USD
CY2020	us-gaap	Increase Decrease In Other Operating Assets IncreaseDecreaseInOtherOperatingAssets	7480000	USD
CY2019	us-gaap	Increase Decrease In Other Operating Assets IncreaseDecreaseInOtherOperatingAssets	-31920000	USD
CY2018	us-gaap	Increase Decrease In Other Operating Assets IncreaseDecreaseInOtherOperatingAssets	35113000	USD
CY2020	us-gaap	Increase Decrease In Accrued Liabilities And Other Operating Liabilities IncreaseDecreaseInAccruedLiabilitiesAndOtherOperatingLiabilities	50508000	USD
CY2019	us-gaap	Increase Decrease In Accrued Liabilities And Other Operating Liabilities IncreaseDecreaseInAccruedLiabilitiesAndOtherOperatingLiabilities	-35886000	USD
CY2018	us-gaap	Increase Decrease In Accrued Liabilities And Other Operating Liabilities IncreaseDecreaseInAccruedLiabilitiesAndOtherOperatingLiabilities	33978000	USD
CY2020	us-gaap	Increase Decrease In Accrued Income Taxes Payable IncreaseDecreaseInAccruedIncomeTaxesPayable	-15745000	USD
CY2020	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	202543000	USD
CY2019	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	256078000	USD
CY2018	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	226980000	USD
CY2020	sfnc	Proceeds From Loan Originations And Principal Collections Net ProceedsFromLoanOriginationsAndPrincipalCollectionsNet	-1327248000	USD
CY2019	sfnc	Proceeds From Loan Originations And Principal Collections Net ProceedsFromLoanOriginationsAndPrincipalCollectionsNet	-23806000	USD
CY2020	us-gaap	Proceeds From Sale Of Loans Receivable ProceedsFromSaleOfLoansReceivable	49736000	USD
CY2019	us-gaap	Proceeds From Sale Of Loans Receivable ProceedsFromSaleOfLoansReceivable	104587000	USD
CY2018	us-gaap	Proceeds From Sale Of Property Plant And Equipment ProceedsFromSaleOfPropertyPlantAndEquipment	0	USD
CY2020	us-gaap	Proceeds From Sale Of Foreclosed Assets ProceedsFromSaleOfForeclosedAssets	10788000	USD
CY2019	us-gaap	Proceeds From Sale Of Foreclosed Assets ProceedsFromSaleOfForeclosedAssets	17986000	USD
CY2018	us-gaap	Proceeds From Sale Of Foreclosed Assets ProceedsFromSaleOfForeclosedAssets	27751000	USD
CY2018	us-gaap	Proceeds From Sale Of Loans Receivable ProceedsFromSaleOfLoansReceivable	24977000	USD
CY2020	us-gaap	Proceeds From Payments For In Interest Bearing Deposits In Banks ProceedsFromPaymentsForInInterestBearingDepositsInBanks	2975000	USD
CY2019	us-gaap	Proceeds From Payments For In Interest Bearing Deposits In Banks ProceedsFromPaymentsForInInterestBearingDepositsInBanks	1130000	USD
CY2018	us-gaap	Proceeds From Payments For In Interest Bearing Deposits In Banks ProceedsFromPaymentsForInInterestBearingDepositsInBanks	-1620000	USD
CY2020	us-gaap	Payments To Acquire Property Plant And Equipment PaymentsToAcquirePropertyPlantAndEquipment	13272000	USD
CY2019	us-gaap	Payments To Acquire Property Plant And Equipment PaymentsToAcquirePropertyPlantAndEquipment	67831000	USD
CY2018	us-gaap	Payments To Acquire Property Plant And Equipment PaymentsToAcquirePropertyPlantAndEquipment	29740000	USD
CY2020	us-gaap	Proceeds From Sale Of Property Plant And Equipment ProceedsFromSaleOfPropertyPlantAndEquipment	369000	USD
CY2019	us-gaap	Proceeds From Sale Of Property Plant And Equipment ProceedsFromSaleOfPropertyPlantAndEquipment	0	USD
CY2020	us-gaap	Proceeds From Sale Of Available For Sale Securities Debt ProceedsFromSaleOfAvailableForSaleSecuritiesDebt	1717364000	USD
CY2019	us-gaap	Proceeds From Sale Of Available For Sale Securities Debt ProceedsFromSaleOfAvailableForSaleSecuritiesDebt	1226578000	USD
CY2018	us-gaap	Proceeds From Sale Of Available For Sale Securities Debt ProceedsFromSaleOfAvailableForSaleSecuritiesDebt	0	USD
CY2020	us-gaap	Proceeds From Maturities Prepayments And Calls Of Available For Sale Securities ProceedsFromMaturitiesPrepaymentsAndCallsOfAvailableForSaleSecurities	2346930000	USD
CY2019	us-gaap	Proceeds From Maturities Prepayments And Calls Of Available For Sale Securities ProceedsFromMaturitiesPrepaymentsAndCallsOfAvailableForSaleSecurities	793270000	USD
CY2018	us-gaap	Proceeds From Maturities Prepayments And Calls Of Available For Sale Securities ProceedsFromMaturitiesPrepaymentsAndCallsOfAvailableForSaleSecurities	258182000	USD
CY2020	us-gaap	Payments To Acquire Available For Sale Securities Debt PaymentsToAcquireAvailableForSaleSecuritiesDebt	4140963000	USD
CY2019	us-gaap	Payments To Acquire Available For Sale Securities Debt PaymentsToAcquireAvailableForSaleSecuritiesDebt	1708948000	USD
CY2018	us-gaap	Payments To Acquire Available For Sale Securities Debt PaymentsToAcquireAvailableForSaleSecuritiesDebt	784113000	USD
CY2020	us-gaap	Proceeds From Maturities Prepayments And Calls Of Held To Maturity Securities ProceedsFromMaturitiesPrepaymentsAndCallsOfHeldToMaturitySecurities	13970000	USD
CY2019	us-gaap	Proceeds From Maturities Prepayments And Calls Of Held To Maturity Securities ProceedsFromMaturitiesPrepaymentsAndCallsOfHeldToMaturitySecurities	31969000	USD
CY2018	us-gaap	Proceeds From Maturities Prepayments And Calls Of Held To Maturity Securities ProceedsFromMaturitiesPrepaymentsAndCallsOfHeldToMaturitySecurities	80803000	USD
CY2020	us-gaap	Payments To Acquire Held To Maturity Securities PaymentsToAcquireHeldToMaturitySecurities	308854000	USD
CY2019	us-gaap	Payments To Acquire Held To Maturity Securities PaymentsToAcquireHeldToMaturitySecurities	0	USD
CY2018	us-gaap	Payments To Acquire Held To Maturity Securities PaymentsToAcquireHeldToMaturitySecurities	1172000	USD
CY2020	us-gaap	Proceeds From Life Insurance Policies ProceedsFromLifeInsurancePolicies	2018000	USD
CY2019	us-gaap	Proceeds From Life Insurance Policies ProceedsFromLifeInsurancePolicies	2435000	USD
CY2018	us-gaap	Proceeds From Life Insurance Policies ProceedsFromLifeInsurancePolicies	1814000	USD
CY2020	us-gaap	Payments To Acquire Life Insurance Policies PaymentsToAcquireLifeInsurancePolicies	0	USD
CY2019	us-gaap	Payments To Acquire Life Insurance Policies PaymentsToAcquireLifeInsurancePolicies	0	USD
CY2018	us-gaap	Payments To Acquire Life Insurance Policies PaymentsToAcquireLifeInsurancePolicies	4000000	USD
CY2020	us-gaap	Payments To Acquire Businesses Net Of Cash Acquired PaymentsToAcquireBusinessesNetOfCashAcquired	0	USD
CY2019	us-gaap	Payments To Acquire Businesses Net Of Cash Acquired PaymentsToAcquireBusinessesNetOfCashAcquired	-178260000	USD
CY2018	us-gaap	Payments To Acquire Businesses Net Of Cash Acquired PaymentsToAcquireBusinessesNetOfCashAcquired	0	USD
CY2020	sfnc	Proceeds From Divestiture Of Businesses Net Of Liabilities ProceedsFromDivestitureOfBusinessesNetOfLiabilities	181560000	USD
CY2019	sfnc	Proceeds From Divestiture Of Businesses Net Of Liabilities ProceedsFromDivestitureOfBusinessesNetOfLiabilities	1235000	USD
CY2018	sfnc	Proceeds From Divestiture Of Businesses Net Of Liabilities ProceedsFromDivestitureOfBusinessesNetOfLiabilities	-55211000	USD
CY2020	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	1189869000	USD
CY2019	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	604477000	USD
CY2018	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-1395122000	USD
CY2020	us-gaap	Increase Decrease In Deposits IncreaseDecreaseInDeposits	1086713000	USD
CY2019	us-gaap	Increase Decrease In Deposits IncreaseDecreaseInDeposits	-404826000	USD
CY2018	us-gaap	Increase Decrease In Deposits IncreaseDecreaseInDeposits	1305877000	USD
CY2020	us-gaap	Proceeds From Issuance Of Subordinated Long Term Debt ProceedsFromIssuanceOfSubordinatedLongTermDebt	0	USD
CY2020	us-gaap	Proceeds From Repayments Of Other Debt ProceedsFromRepaymentsOfOtherDebt	45983000	USD
CY2019	us-gaap	Proceeds From Issuance Of Subordinated Long Term Debt ProceedsFromIssuanceOfSubordinatedLongTermDebt	25500000	USD
CY2018	us-gaap	Proceeds From Issuance Of Subordinated Long Term Debt ProceedsFromIssuanceOfSubordinatedLongTermDebt	326355000	USD
CY2020	us-gaap	Repayments Of Subordinated Debt RepaymentsOfSubordinatedDebt	7442000	USD
CY2019	us-gaap	Repayments Of Subordinated Debt RepaymentsOfSubordinatedDebt	0	USD
CY2018	us-gaap	Repayments Of Subordinated Debt RepaymentsOfSubordinatedDebt	113990000	USD
CY2020	us-gaap	Payments Of Dividends Preferred Stock And Preference Stock PaymentsOfDividendsPreferredStockAndPreferenceStock	52000	USD
CY2019	us-gaap	Payments Of Dividends Preferred Stock And Preference Stock PaymentsOfDividendsPreferredStockAndPreferenceStock	339000	USD
CY2018	us-gaap	Payments Of Dividends Preferred Stock And Preference Stock PaymentsOfDividendsPreferredStockAndPreferenceStock	0	USD
CY2020	us-gaap	Payments Of Dividends Common Stock PaymentsOfDividendsCommonStock	74593000	USD
CY2019	us-gaap	Payments Of Dividends Common Stock PaymentsOfDividendsCommonStock	63921000	USD
CY2018	us-gaap	Payments Of Dividends Common Stock PaymentsOfDividendsCommonStock	55646000	USD
CY2019	us-gaap	Proceeds From Repayments Of Other Debt ProceedsFromRepaymentsOfOtherDebt	-240806000	USD
CY2018	us-gaap	Proceeds From Repayments Of Other Debt ProceedsFromRepaymentsOfOtherDebt	-34574000	USD
CY2020	us-gaap	Proceeds From Payments For In Securities Sold Under Agreements To Repurchase ProceedsFromPaymentsForInSecuritiesSoldUnderAgreementsToRepurchase	148966000	USD
CY2019	us-gaap	Proceeds From Payments For In Securities Sold Under Agreements To Repurchase ProceedsFromPaymentsForInSecuritiesSoldUnderAgreementsToRepurchase	40207000	USD
CY2018	us-gaap	Proceeds From Payments For In Securities Sold Under Agreements To Repurchase ProceedsFromPaymentsForInSecuritiesSoldUnderAgreementsToRepurchase	-26652000	USD
CY2020	sfnc	Proceeds From Payments For Issuance Of Shares Share Based Payment Arrangement Including Option Exercised And Canceled ProceedsFromPaymentsForIssuanceOfSharesShareBasedPaymentArrangementIncludingOptionExercisedAndCanceled	-4087000	USD
CY2019	sfnc	Proceeds From Payments For Issuance Of Shares Share Based Payment Arrangement Including Option Exercised And Canceled ProceedsFromPaymentsForIssuanceOfSharesShareBasedPaymentArrangementIncludingOptionExercisedAndCanceled	-2389000	USD
CY2018	sfnc	Proceeds From Payments For Issuance Of Shares Share Based Payment Arrangement Including Option Exercised And Canceled ProceedsFromPaymentsForIssuanceOfSharesShareBasedPaymentArrangementIncludingOptionExercisedAndCanceled	1162000	USD
CY2020	us-gaap	Proceeds From Stock Plans ProceedsFromStockPlans	956000	USD
CY2019	us-gaap	Proceeds From Stock Plans ProceedsFromStockPlans	1312000	USD
CY2018	us-gaap	Proceeds From Stock Plans ProceedsFromStockPlans	1026000	USD
CY2020	us-gaap	Payments For Repurchase Of Common Stock PaymentsForRepurchaseOfCommonStock	113327000	USD
CY2019	us-gaap	Payments For Repurchase Of Common Stock PaymentsForRepurchaseOfCommonStock	10128000	USD
CY2018	us-gaap	Payments For Repurchase Of Common Stock PaymentsForRepurchaseOfCommonStock	0	USD
CY2020	us-gaap	Payments For Repurchase Of Redeemable Preferred Stock PaymentsForRepurchaseOfRedeemablePreferredStock	0	USD
CY2019	us-gaap	Payments For Repurchase Of Redeemable Preferred Stock PaymentsForRepurchaseOfRedeemablePreferredStock	42000000	USD
CY2018	us-gaap	Payments For Repurchase Of Redeemable Preferred Stock PaymentsForRepurchaseOfRedeemablePreferredStock	0	USD
CY2020	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	1083117000	USD
CY2019	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	-697390000	USD
CY2018	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	1403558000	USD
CY2020	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Including Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect	2475529000	USD
CY2019	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Including Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect	163165000	USD
CY2018	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Including Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect	235416000	USD
CY2018	us-gaap	Stock Issued During Period Shares Share Based Compensation StockIssuedDuringPeriodSharesShareBasedCompensation	278743	shares
CY2018	us-gaap	Stock Issued During Period Value Share Based Compensation StockIssuedDuringPeriodValueShareBasedCompensation	10887000	USD
CY2019Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	996623000	USD
CY2018Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	833458000	USD
CY2017Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	598042000	USD
CY2020Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	3472152000	USD
CY2019Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	996623000	USD
CY2018Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	833458000	USD
CY2017Q4	us-gaap	Stockholders Equity StockholdersEquity	2084564000	USD
CY2018	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	205603000	USD
CY2018	us-gaap	Stock Issued During Period Shares Employee Stock Purchase Plans StockIssuedDuringPeriodSharesEmployeeStockPurchasePlans	39782	shares
CY2018	us-gaap	Stock Issued During Period Value Employee Stock Purchase Plan StockIssuedDuringPeriodValueEmployeeStockPurchasePlan	1026000	USD
CY2018	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	0.60
CY2018	us-gaap	Dividends Common Stock DividendsCommonStock	55646000	USD
CY2018Q4	us-gaap	Stockholders Equity StockholdersEquity	2246434000	USD
CY2020	us-gaap	Stock Issued During Period Shares Share Based Compensation StockIssuedDuringPeriodSharesShareBasedCompensation	362080	shares
CY2020	us-gaap	Stock Issued During Period Value Share Based Compensation StockIssuedDuringPeriodValueShareBasedCompensation	9110000	USD
CY2020	us-gaap	Stock Repurchased During Period Shares StockRepurchasedDuringPeriodShares	5956700	shares
CY2020	us-gaap	Stock Repurchased During Period Value StockRepurchasedDuringPeriodValue	113327000	USD
CY2020	us-gaap	Dividends Preferred Stock DividendsPreferredStock	52000	USD
CY2020	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	0.68
CY2020	us-gaap	Dividends Common Stock DividendsCommonStock	74593000	USD
CY2020Q4	us-gaap	Stockholders Equity StockholdersEquity	2976656000	USD
CY2020Q4	sfnc	Number Of Financial Centers NumberOfFinancialCenters	204	financial_center
CY2020	us-gaap	Financing Receivable Allowance For Credit Losses Policy For Uncollectible Amounts FinancingReceivableAllowanceForCreditLossesPolicyForUncollectibleAmounts	<div style="text-align:justify"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:700;line-height:120%">Allowance for Credit Losses</span></div><div style="text-align:justify"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%"> </span></div><div style="text-align:justify"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">On January 1, 2020, the Company was required to adopt a new credit loss methodology, the Current Expected Credit Losses (“CECL”) methodology. See Note 20, New Accounting Standards, for additional information regarding adoption.</span></div><div style="text-align:justify"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%"> </span></div><div style="text-align:justify"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">The allowance for credit losses is a reserve established through a provision for credit losses charged to expense, which represents management’s best estimate of lifetime expected losses based on reasonable and supportable forecasts, historical loss experience, and other qualitative considerations. The allowance, in the judgment of management, is necessary to reserve for expected loan losses and risks inherent in the loan portfolio. The Company’s allowance for credit loss methodology includes reserve factors calculated to estimate current expected credit losses to amortized cost balances over the remaining contractual life of the portfolio, adjusted for prepayments, in accordance with ASC Topic 326-20, </span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-style:italic;font-weight:400;line-height:120%">Financial Instruments - Credit Losses</span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">. Accordingly, the methodology is based on the Company’s reasonable and supportable economic forecasts, historical loss experience, and other qualitative adjustments. Management’s evaluation of the allowance for credit losses is inherently subjective as it requires material estimates. It is management’s practice to review the allowance on a monthly basis, and after considering the factors previously noted, to determine the level of provision made to the allowance.</span></div><div style="text-align:justify"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">Loans with similar risk characteristics such as loan type, collateral type, and internal risk ratings are aggregated into homogeneous segments for assessment. Reserve factors are based on estimated probability of default and loss given default for each segment. The estimates are determined based on economic forecasts over the reasonable and supportable forecast period based on projected performance of economic variables that have a statistical relationship with the historical loss experience of the segments. For contractual periods that extend beyond the one-year forecast period, the estimates revert to average historical loss experiences over a one-year period on a straight-line basis.</span></div><div style="text-align:justify"><span><br/></span></div><div style="text-align:justify"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">The Company also includes qualitative adjustments to the allowance based on factors and considerations that have not otherwise been fully accounted for. Qualitative adjustments include, but are not limited to:</span></div><div style="text-align:justify"><span><br/></span></div><div style="margin-bottom:3pt;padding-left:18pt;text-align:justify;text-indent:-18pt"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">•</span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-style:italic;font-weight:400;line-height:120%;padding-left:14.5pt">Changes in asset quality - </span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">Adjustments related to trending credit quality metrics including delinquency, nonperforming loans, charge-offs, and risk ratings that may not be fully accounted for in the reserve factor.</span></div><div style="margin-bottom:3pt;padding-left:18pt;text-align:justify;text-indent:-18pt"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">•</span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-style:italic;font-weight:400;line-height:120%;padding-left:14.5pt">Changes in the nature and volume of the portfolio</span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%"> - Adjustments related to current changes in the loan portfolio that are not fully represented or accounted for in the reserve factors.</span></div><div style="margin-bottom:3pt;padding-left:18pt;text-align:justify;text-indent:-18pt"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">•</span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-style:italic;font-weight:400;line-height:120%;padding-left:14.5pt">Changes in lending and loan monitoring policies and procedures</span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%"> - Adjustments related to current changes in lending and loan monitoring procedures as well as review of specific internal policy compliance metrics.</span></div><div style="margin-bottom:3pt;padding-left:18pt;text-align:justify;text-indent:-18pt"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">•</span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-style:italic;font-weight:400;line-height:120%;padding-left:14.5pt">Changes in the experience, ability, and depth of lending management and other relevant staff</span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%"> - Adjustments to measure increasing or decreasing credit risk related to lending and loan monitoring management.</span></div><div style="margin-bottom:3pt;padding-left:18pt;text-align:justify;text-indent:-18pt"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">•</span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-style:italic;font-weight:400;line-height:120%;padding-left:14.5pt">Changes in the value of underlying collateral of collateralized loans </span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">- Adjustments related to improving or deterioration of the value of underlying collateral that are not fully captured in the reserve factors.</span></div><div style="margin-bottom:3pt;padding-left:18pt;text-align:justify;text-indent:-18pt"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">•</span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-style:italic;font-weight:400;line-height:120%;padding-left:14.5pt">Changes in and the existence and effect of any concentrations of credit</span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%"> - Adjustments related to credit risk of specific industries that are not fully captured in the reserve factors.</span></div><div style="margin-bottom:3pt;padding-left:18pt;text-align:justify;text-indent:-18pt"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">•</span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-style:italic;font-weight:400;line-height:120%;padding-left:14.5pt">Changes in regional and local economic and business conditions and developments </span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">- Adjustments related to expected and current economic conditions at a regional or local-level that are not fully captured within the Company’s reasonable and supportable forecast.</span></div><div style="margin-bottom:9pt;padding-left:18pt;text-align:justify;text-indent:-18pt"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">•</span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-style:italic;font-weight:400;line-height:120%;padding-left:14.5pt">Data imprecisions due to limited historical loss data</span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%"> - Adjustments related to limited historical loss data that is representative of the collective loan portfolio.</span></div><div style="text-align:justify"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-style:italic;font-weight:400;line-height:120%">Collateral Dependent Loans</span></div><div><span><br/></span></div><div style="text-align:justify"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">Loans that do not share risk characteristics are evaluated on an individual basis. For collateral dependent financial assets where the Company has determined that foreclosure of the collateral is probable, or where the borrower is experiencing financial difficulty and the Company expects repayment of the financial asset to be provided substantially through the operation or sale of the collateral, the allowance for credit loss is measured based on the difference between the fair value of the collateral and the amortized cost basis of the asset as of the measurement date. When repayment is expected to be from the operation of the collateral, expected credit losses are calculated as the amount by which the amortized cost basis of the financial asset exceeds the present value of expected cash flows from the operation of the collateral. When repayment is expected to be from the sale of the collateral, expected credit losses are calculated as the amount by which the amortized costs basis of the financial asset exceeds the fair value of the underlying collateral less estimated cost to sell. The allowance for credit losses may be zero if the fair value of the collateral at the measurement date exceeds the amortized cost basis of the financial asset.</span></div><div style="text-align:justify"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%"> </span></div><div style="text-align:justify"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">For a collateral dependent loan, the Company’s evaluation process includes a valuation by appraisal or other collateral analysis adjusted for selling costs, when appropriate. This valuation is compared to the remaining outstanding principal balance of the loan. If a loss is determined to be probable, the loss is included in the allowance for credit losses as a specific allocation. If the loan is not collateral dependent, the measurement of loss is based on the difference between the expected and contractual future cash flows of the loan.</span></div><div style="text-align:justify"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-style:italic;font-weight:400;line-height:120%">Allowance for Credit Losses Prior to the Adoption of CECL</span></div><div style="text-align:justify"><span><br/></span></div><div style="text-align:justify"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">Prior to 2020, management categorized the allowance for credit losses by either general reserves or specific reserves. The allowance for credit losses was based on management’s assessment of several factors such as (1) historical loss experience based on volumes and types, (2) volume and trends in delinquencies and nonaccruals, (3) lending policies and procedures including those for credit losses, collections and recoveries, (4) national, state and local economic trends and conditions, (5) external factors and pressure from competition, (6) the experience, ability and depth of lending management and staff, (7) seasoning of new products obtained and new markets entered through acquisition and (8) other factors and trends that affected specific loans and categories of loans. The Company established general allocations for each major loan category. This category also included allocations to loans which were collectively evaluated for loss such as credit cards, one-to-four family owner occupied residential real estate loans and other consumer loans. General reserves were established, based upon the aforementioned factors and allocated to the individual loan categories.</span></div><div style="text-align:justify"><span><br/></span></div><div style="text-align:justify"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">Specific reserves were provided on loans that were considered impaired when it was probable that the Company would not receive all amounts due according to the contractual terms of the loan, including scheduled principal and interest payments. This included loans that were delinquent 90 days or more, nonaccrual loans and certain other loans identified by management. Specific reserves were accrued for probable losses on specific loans evaluated for impairment for which the basis of each loan, including accrued interest, exceeded the discounted amount of expected future collections of interest and principal or, alternatively, the fair value of loan collateral.</span></div>
CY2020	us-gaap	Number Of Reportable Segments NumberOfReportableSegments	1	segment
CY2020	us-gaap	Use Of Estimates UseOfEstimates	<div style="text-align:justify"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:700;line-height:120%">Use of Estimates</span></div><div style="text-align:justify"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%"> </span></div><div style="text-align:justify"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">The preparation of financial statements, in accordance with US GAAP, requires management to make estimates and assumptions that affect the reported amounts of assets, liabilities, income items and expenses and disclosure of contingent assets and liabilities. The estimates and assumptions used in the accompanying consolidated financial statements are based upon management’s evaluation of the relevant facts and circumstances as of the date of the consolidated financial statements and actual results may differ from these estimates. Such estimates include, but are not limited to, the Company’s allowance for credit losses.</span></div><div style="text-align:justify"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%"> </span></div><div style="text-align:justify"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">Material estimates that are particularly susceptible to significant change relate to the determination of the allowance for credit losses, the valuation of real estate acquired in connection with foreclosures or in satisfaction of loans and the valuation of acquired loans. Management obtains independent appraisals for significant properties in connection with the determination of the allowance for credit losses and the valuation of foreclosed assets.</span></div>
CY2020	us-gaap	Prior Period Reclassification Adjustment Description PriorPeriodReclassificationAdjustmentDescription	<div style="text-align:justify"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:700;line-height:120%">Reclassifications</span></div><div style="text-align:justify"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%"> </span></div><div style="text-align:justify"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">During 2020, the Company moved “equity securities” from the “available-for-sale investment securities” into “other assets.” The change had no impact on net income. Various items within the accompanying consolidated financial statements for previous years have been reclassified to provide more comparative information. These reclassifications were not material to the consolidated financial statements.</span></div>
CY2019	us-gaap	Stock Repurchased During Period Shares StockRepurchasedDuringPeriodShares	390000	shares
CY2019	us-gaap	Stock Repurchased During Period Value StockRepurchasedDuringPeriodValue	10128000	USD
CY2019	us-gaap	Dividends Preferred Stock DividendsPreferredStock	339000	USD
CY2019	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	0.64
CY2019	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	286432000	USD
CY2019	us-gaap	Stock Issued During Period Shares Employee Stock Purchase Plans StockIssuedDuringPeriodSharesEmployeeStockPurchasePlans	60413	shares
CY2019	us-gaap	Stock Issued During Period Value Employee Stock Purchase Plan StockIssuedDuringPeriodValueEmployeeStockPurchasePlan	1312000	USD
CY2019	us-gaap	Stock Issued During Period Shares Share Based Compensation StockIssuedDuringPeriodSharesShareBasedCompensation	261200	shares
CY2019	us-gaap	Stock Issued During Period Value Share Based Compensation StockIssuedDuringPeriodValueShareBasedCompensation	10532000	USD
CY2019	sfnc	Preferred Stock Retired During Period Value PreferredStockRetiredDuringPeriodValue	42000000	USD
CY2019	us-gaap	Dividends Common Stock DividendsCommonStock	63921000	USD
CY2019Q4	us-gaap	Stockholders Equity StockholdersEquity	2988924000	USD
CY2020	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	293739000	USD
CY2020	us-gaap	Stock Issued During Period Shares Employee Stock Purchase Plans StockIssuedDuringPeriodSharesEmployeeStockPurchasePlans	43681	shares
CY2020	us-gaap	Stock Issued During Period Value Employee Stock Purchase Plan StockIssuedDuringPeriodValueEmployeeStockPurchasePlan	956000	USD
CY2018Q1	us-gaap	Stockholders Equity Note Stock Split Conversion Ratio1 StockholdersEquityNoteStockSplitConversionRatio1	2
CY2020	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	254852000	USD
CY2019	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	237828000	USD
CY2018	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	215713000	USD
CY2020	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	109860000	shares
CY2019	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	98351000	shares
CY2018	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	92268000	shares
CY2020	us-gaap	Weighted Average Number Diluted Shares Outstanding Adjustment WeightedAverageNumberDilutedSharesOutstandingAdjustment	313000	shares
CY2019	us-gaap	Weighted Average Number Diluted Shares Outstanding Adjustment WeightedAverageNumberDilutedSharesOutstandingAdjustment	446000	shares
CY2018	us-gaap	Weighted Average Number Diluted Shares Outstanding Adjustment WeightedAverageNumberDilutedSharesOutstandingAdjustment	562000	shares
CY2020	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	110173000	shares
CY2019	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	98797000	shares
CY2018	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	92830000	shares
CY2020	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	2.32
CY2019	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	2.42
CY2018	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	2.34
CY2020	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	2.31
CY2019	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	2.41
CY2018	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	2.32
CY2020Q4	us-gaap	Held To Maturity Securities HeldToMaturitySecurities	335946000	USD
CY2020Q4	us-gaap	Debt Securities Held To Maturity Allowance For Credit Loss DebtSecuritiesHeldToMaturityAllowanceForCreditLoss	2915000	USD
CY2020Q4	us-gaap	Debt Securities Available For Sale Allowance For Credit Loss DebtSecuritiesAvailableForSaleAllowanceForCreditLoss	312000	USD
CY2020Q4	sfnc	Debt Securities Held To Maturity Net Of Allowance For Credit Losses DebtSecuritiesHeldToMaturityNetOfAllowanceForCreditLosses	333031000	USD
CY2020Q4	us-gaap	Held To Maturity Securities Accumulated Unrecognized Holding Gain HeldToMaturitySecuritiesAccumulatedUnrecognizedHoldingGain	8924000	USD
CY2020Q4	us-gaap	Held To Maturity Securities Accumulated Unrecognized Holding Loss HeldToMaturitySecuritiesAccumulatedUnrecognizedHoldingLoss	30000	USD
CY2020Q4	us-gaap	Held To Maturity Securities Fair Value HeldToMaturitySecuritiesFairValue	341925000	USD
CY2019Q4	us-gaap	Held To Maturity Securities HeldToMaturitySecurities	40927000	USD
CY2019Q4	us-gaap	Debt Securities Held To Maturity Allowance For Credit Loss DebtSecuritiesHeldToMaturityAllowanceForCreditLoss	0	USD
CY2019Q4	sfnc	Debt Securities Held To Maturity Net Of Allowance For Credit Losses DebtSecuritiesHeldToMaturityNetOfAllowanceForCreditLosses	40927000	USD
CY2019Q4	us-gaap	Held To Maturity Securities Accumulated Unrecognized Holding Gain HeldToMaturitySecuritiesAccumulatedUnrecognizedHoldingGain	987000	USD
CY2019Q4	us-gaap	Held To Maturity Securities Accumulated Unrecognized Holding Loss HeldToMaturitySecuritiesAccumulatedUnrecognizedHoldingLoss	59000	USD
CY2019Q4	us-gaap	Held To Maturity Securities Fair Value HeldToMaturitySecuritiesFairValue	41855000	USD
CY2020Q4	us-gaap	Available For Sale Debt Securities Amortized Cost Basis AvailableForSaleDebtSecuritiesAmortizedCostBasis	3397043000	USD
CY2020Q4	us-gaap	Available For Sale Debt Securities Accumulated Gross Unrealized Gain Before Tax AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedGainBeforeTax	79663000	USD
CY2020Q4	us-gaap	Available For Sale Debt Securities Accumulated Gross Unrealized Loss Before Tax AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedLossBeforeTax	2796000	USD
CY2020Q4	us-gaap	Available For Sale Securities Debt Securities AvailableForSaleSecuritiesDebtSecurities	3473598000	USD
CY2020Q4	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position Less Than12 Months Accumulated Loss DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss	1602000	USD
CY2019Q4	us-gaap	Available For Sale Debt Securities Amortized Cost Basis AvailableForSaleDebtSecuritiesAmortizedCostBasis	3263151000	USD
CY2019Q4	us-gaap	Debt Securities Available For Sale Allowance For Credit Loss DebtSecuritiesAvailableForSaleAllowanceForCreditLoss	0	USD
CY2019Q4	us-gaap	Available For Sale Debt Securities Accumulated Gross Unrealized Gain Before Tax AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedGainBeforeTax	31740000	USD
CY2019Q4	us-gaap	Available For Sale Debt Securities Accumulated Gross Unrealized Loss Before Tax AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedLossBeforeTax	6548000	USD
CY2019Q4	us-gaap	Available For Sale Securities Debt Securities AvailableForSaleSecuritiesDebtSecurities	3288343000	USD
CY2020Q4	sfnc	Debt Securities Heldtomaturity Interest Receivable DebtSecuritiesHeldtomaturityInterestReceivable	1000000.0	USD
CY2020Q4	sfnc	Debt Securities Availableforsale Interest Receivable DebtSecuritiesAvailableforsaleInterestReceivable	17100000	USD
CY2020Q4	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position Less Than12 Months DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12Months	502386000	USD
CY2020Q4	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position12 Months Or Longer DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLonger	56895000	USD
CY2020Q4	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position12 Months Or Longer Accumulated Loss DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLongerAccumulatedLoss	882000	USD
CY2020Q4	us-gaap	Debt Securities Available For Sale Unrealized Loss Position DebtSecuritiesAvailableForSaleUnrealizedLossPosition	559281000	USD
CY2020Q4	us-gaap	Debt Securities Available For Sale Unrealized Loss Position Accumulated Loss DebtSecuritiesAvailableForSaleUnrealizedLossPositionAccumulatedLoss	2484000	USD
CY2020	us-gaap	Debt Securities Available For Sale Allowance For Credit Loss Not To Sell Before Recovery Credit Loss Previously Recorded Expense Reversal DebtSecuritiesAvailableForSaleAllowanceForCreditLossNotToSellBeforeRecoveryCreditLossPreviouslyRecordedExpenseReversal	-129000	USD
CY2020Q4	us-gaap	Debt Securities Available For Sale Allowance For Credit Loss DebtSecuritiesAvailableForSaleAllowanceForCreditLoss	312000	USD
CY2020	us-gaap	Debt Securities Available For Sale Change In Present Value Expense Reversal DebtSecuritiesAvailableForSaleChangeInPresentValueExpenseReversal	-61000	USD
CY2020Q4	us-gaap	Available For Sale Securities Debt Securities AvailableForSaleSecuritiesDebtSecurities	3500000000	USD
CY2020Q4	us-gaap	Debt Securities Available For Sale Unrealized Loss Position DebtSecuritiesAvailableForSaleUnrealizedLossPosition	559300000	USD
CY2020Q4	sfnc	Debt Securities Unrealized Loss Position Quantitative Disclosure Percent DebtSecuritiesUnrealizedLossPositionQuantitativeDisclosurePercent	0.161
CY2019Q4	us-gaap	Debt Securities Held To Maturity Allowance For Credit Loss DebtSecuritiesHeldToMaturityAllowanceForCreditLoss	0	USD
CY2020	us-gaap	Debt Securities Held To Maturity Credit Loss Expense Reversal DebtSecuritiesHeldToMaturityCreditLossExpenseReversal	2546000	USD
CY2020Q4	us-gaap	Debt Securities Held To Maturity Allowance For Credit Loss DebtSecuritiesHeldToMaturityAllowanceForCreditLoss	2915000	USD
CY2019Q4	us-gaap	Debt Securities Available For Sale Allowance For Credit Loss DebtSecuritiesAvailableForSaleAllowanceForCreditLoss	0	USD
CY2020	us-gaap	Debt Securities Available For Sale Allowance For Credit Loss Not Previously Recorded DebtSecuritiesAvailableForSaleAllowanceForCreditLossNotPreviouslyRecorded	312000	USD
CY2020	us-gaap	Debt Securities Available For Sale Allowance For Credit Loss Securities Sold DebtSecuritiesAvailableForSaleAllowanceForCreditLossSecuritiesSold	244000	USD
CY2020Q4	us-gaap	Available For Sale Securities Debt Maturities After One Through Five Years Amortized Cost AvailableForSaleSecuritiesDebtMaturitiesAfterOneThroughFiveYearsAmortizedCost	30634000	USD
CY2020	us-gaap	Investment Income Interest InvestmentIncomeInterest	64533000	USD
CY2019	us-gaap	Investment Income Interest InvestmentIncomeInterest	63376000	USD
CY2018	us-gaap	Investment Income Interest InvestmentIncomeInterest	53460000	USD
CY2020Q4	us-gaap	Held To Maturity Securities Debt Maturities Within One Year Net Carrying Amount HeldToMaturitySecuritiesDebtMaturitiesWithinOneYearNetCarryingAmount	5821000	USD
CY2020Q4	us-gaap	Held To Maturity Securities Debt Maturities Within One Year Fair Value HeldToMaturitySecuritiesDebtMaturitiesWithinOneYearFairValue	5895000	USD
CY2020Q4	us-gaap	Available For Sale Securities Debt Maturities Within One Year Amortized Cost AvailableForSaleSecuritiesDebtMaturitiesWithinOneYearAmortizedCost	14017000	USD
CY2020Q4	us-gaap	Available For Sale Securities Debt Maturities Within One Year Fair Value AvailableForSaleSecuritiesDebtMaturitiesWithinOneYearFairValue	14089000	USD
CY2020Q4	us-gaap	Held To Maturity Securities Debt Maturities After One Through Five Years Net Carrying Amount HeldToMaturitySecuritiesDebtMaturitiesAfterOneThroughFiveYearsNetCarryingAmount	10708000	USD
CY2020Q4	us-gaap	Held To Maturity Securities Debt Maturities After One Through Five Years Fair Value HeldToMaturitySecuritiesDebtMaturitiesAfterOneThroughFiveYearsFairValue	11199000	USD
CY2020Q4	us-gaap	Available For Sale Securities Debt Maturities After One Through Five Years Fair Value AvailableForSaleSecuritiesDebtMaturitiesAfterOneThroughFiveYearsFairValue	31071000	USD
CY2020Q4	us-gaap	Held To Maturity Securities Debt Maturities After Five Through Ten Years Net Carrying Amount HeldToMaturitySecuritiesDebtMaturitiesAfterFiveThroughTenYearsNetCarryingAmount	5227000	USD
CY2020Q4	us-gaap	Held To Maturity Securities Debt Maturities After Five Through Ten Years Fair Value HeldToMaturitySecuritiesDebtMaturitiesAfterFiveThroughTenYearsFairValue	2937000	USD
CY2020Q4	us-gaap	Available For Sale Securities Debt Maturities After Five Through Ten Years Amortized Cost AvailableForSaleSecuritiesDebtMaturitiesAfterFiveThroughTenYearsAmortizedCost	229042000	USD
CY2020Q4	us-gaap	Available For Sale Securities Debt Maturities After Five Through Ten Years Fair Value AvailableForSaleSecuritiesDebtMaturitiesAfterFiveThroughTenYearsFairValue	232003000	USD
CY2020Q4	us-gaap	Held To Maturity Securities Debt Maturities After Ten Years Net Carrying Amount HeldToMaturitySecuritiesDebtMaturitiesAfterTenYearsNetCarryingAmount	291836000	USD
CY2020Q4	us-gaap	Held To Maturity Securities Debt Maturities After Ten Years Fair Value HeldToMaturitySecuritiesDebtMaturitiesAfterTenYearsFairValue	298857000	USD
CY2020Q4	us-gaap	Available For Sale Securities Debt Maturities After Ten Years Amortized Cost AvailableForSaleSecuritiesDebtMaturitiesAfterTenYearsAmortizedCost	1747650000	USD
CY2020Q4	us-gaap	Available For Sale Securities Debt Maturities After Ten Years Fair Value AvailableForSaleSecuritiesDebtMaturitiesAfterTenYearsFairValue	1800568000	USD
CY2020Q4	us-gaap	Held To Maturity Securities Debt Maturities Single Maturity Date Amortized Cost Basis HeldToMaturitySecuritiesDebtMaturitiesSingleMaturityDateAmortizedCostBasis	22354000	USD
CY2020Q4	us-gaap	Held To Maturity Securities Debt Maturities Single Maturity Date Fair Value HeldToMaturitySecuritiesDebtMaturitiesSingleMaturityDateFairValue	23037000	USD
CY2020Q4	us-gaap	Available For Sale Securities Debt Maturities Single Maturity Date Amortized Cost Basis AvailableForSaleSecuritiesDebtMaturitiesSingleMaturityDateAmortizedCostBasis	1374769000	USD
CY2020Q4	us-gaap	Available For Sale Securities Debt Maturities Single Maturity Date AvailableForSaleSecuritiesDebtMaturitiesSingleMaturityDate	1394936000	USD
CY2020Q4	us-gaap	Available For Sale Securities Debt Maturities Without Single Maturity Date Amortized Cost AvailableForSaleSecuritiesDebtMaturitiesWithoutSingleMaturityDateAmortizedCost	931000	USD
CY2020Q4	us-gaap	Available For Sale Securities Debt Maturities Without Single Maturity Date Fair Value AvailableForSaleSecuritiesDebtMaturitiesWithoutSingleMaturityDateFairValue	931000	USD
CY2020Q4	us-gaap	Held To Maturity Securities HeldToMaturitySecurities	335946000	USD
CY2020Q4	us-gaap	Held To Maturity Securities Fair Value HeldToMaturitySecuritiesFairValue	341925000	USD
CY2020Q4	us-gaap	Available For Sale Debt Securities Amortized Cost Basis AvailableForSaleDebtSecuritiesAmortizedCostBasis	3397043000	USD
CY2020Q4	us-gaap	Available For Sale Securities Debt Securities AvailableForSaleSecuritiesDebtSecurities	3473598000	USD
CY2020Q4	us-gaap	Debt Securities Available For Sale Restricted DebtSecuritiesAvailableForSaleRestricted	2000000000.0	USD
CY2019Q4	us-gaap	Debt Securities Available For Sale Restricted DebtSecuritiesAvailableForSaleRestricted	1700000000	USD
CY2020	us-gaap	Debt Securities Available For Sale Realized Gain DebtSecuritiesAvailableForSaleRealizedGain	54800000	USD
CY2020	us-gaap	Debt Securities Available For Sale Realized Loss DebtSecuritiesAvailableForSaleRealizedLoss	15000	USD
CY2019	us-gaap	Debt Securities Available For Sale Realized Gain DebtSecuritiesAvailableForSaleRealizedGain	13300000	USD
CY2019	us-gaap	Debt Securities Available For Sale Realized Loss DebtSecuritiesAvailableForSaleRealizedLoss	4000	USD
CY2018	us-gaap	Debt Securities Available For Sale Realized Gain DebtSecuritiesAvailableForSaleRealizedGain	65000	USD
CY2018	us-gaap	Debt Securities Available For Sale Realized Loss DebtSecuritiesAvailableForSaleRealizedLoss	4000	USD
CY2020	sfnc	Income Tax Benefit Related To Security Gains Losses Percentage IncomeTaxBenefitRelatedToSecurityGainsLossesPercentage	0.26135
CY2018	sfnc	Income Tax Benefit Related To Security Gains Losses Percentage IncomeTaxBenefitRelatedToSecurityGainsLossesPercentage	0.26135
CY2019	sfnc	Income Tax Benefit Related To Security Gains Losses Percentage IncomeTaxBenefitRelatedToSecurityGainsLossesPercentage	0.26135
CY2020Q4	us-gaap	Notes Receivable Gross NotesReceivableGross	12900000000	USD
CY2019Q4	us-gaap	Notes Receivable Gross NotesReceivableGross	14430000000	USD
CY2020Q4	us-gaap	Notes Receivable Gross NotesReceivableGross	12900897000	USD
CY2019Q4	us-gaap	Notes Receivable Gross NotesReceivableGross	14425704000	USD
CY2020	us-gaap	Financing Receivable Purchased With Credit Deterioration Discount Premium FinancingReceivablePurchasedWithCreditDeteriorationDiscountPremium	57300000	USD
CY2019	us-gaap	Financing Receivable Purchased With Credit Deterioration Discount Premium FinancingReceivablePurchasedWithCreditDeteriorationDiscountPremium	91600000	USD
CY2020Q4	sfnc	Financing Receivable Accrued Interest Excluded From Amortized Costs FinancingReceivableAccruedInterestExcludedFromAmortizedCosts	54400000	USD
CY2019Q4	sfnc	Financing Receivable Accrued Interest Excluded From Amortized Costs FinancingReceivableAccruedInterestExcludedFromAmortizedCosts	48900000	USD
CY2020Q4	us-gaap	Financing Receivable Recorded Investment Nonaccrual Status FinancingReceivableRecordedInvestmentNonaccrualStatus	122879000	USD
CY2020Q4	us-gaap	Financing Receivable Nonaccrual No Allowance FinancingReceivableNonaccrualNoAllowance	16800000	USD
CY2019Q4	us-gaap	Financing Receivable Recorded Investment Nonaccrual Status FinancingReceivableRecordedInvestmentNonaccrualStatus	93330000	USD
CY2020Q4	us-gaap	Financing Receivable Recorded Investment Past Due FinancingReceivableRecordedInvestmentPastDue	74260000	USD
CY2020Q4	us-gaap	Financing Receivable Recorded Investment Current FinancingReceivableRecordedInvestmentCurrent	12826637000	USD
CY2020Q4	us-gaap	Notes Receivable Gross NotesReceivableGross	12900897000	USD
CY2020Q4	us-gaap	Financing Receivable Recorded Investment90 Days Past Due And Still Accruing FinancingReceivableRecordedInvestment90DaysPastDueAndStillAccruing	578000	USD
CY2019Q4	us-gaap	Financing Receivable Recorded Investment Past Due FinancingReceivableRecordedInvestmentPastDue	93989000	USD
CY2019Q4	us-gaap	Financing Receivable Recorded Investment Current FinancingReceivableRecordedInvestmentCurrent	14331715000	USD
CY2019Q4	us-gaap	Notes Receivable Gross NotesReceivableGross	14425704000	USD
CY2019Q4	us-gaap	Financing Receivable Recorded Investment90 Days Past Due And Still Accruing FinancingReceivableRecordedInvestment90DaysPastDueAndStillAccruing	856000	USD
CY2020	us-gaap	Financing Receivable Modifications Number Of Contracts2 FinancingReceivableModificationsNumberOfContracts2	5	loan
CY2020	us-gaap	Financing Receivable Modifications Pre Modification Recorded Investment2 FinancingReceivableModificationsPreModificationRecordedInvestment2	1948000	USD
CY2020	sfnc	Financing Receivable Prior Modifications Numberof Contracts Collected FinancingReceivablePriorModificationsNumberofContractsCollected	6	loan
CY2020	us-gaap	Proceeds From Collection Of Loans Receivable ProceedsFromCollectionOfLoansReceivable	837265	USD
CY2019	us-gaap	Financing Receivable Modifications Number Of Contracts2 FinancingReceivableModificationsNumberOfContracts2	4	loan
CY2019	us-gaap	Financing Receivable Modifications Pre Modification Recorded Investment2 FinancingReceivableModificationsPreModificationRecordedInvestment2	997000	USD
CY2019	sfnc	Financial Impact On Date Of Restructure FinancialImpactOnDateOfRestructure	0	USD
CY2019	sfnc	Financing Receivable Prior Modifications Numberof Contracts Collected FinancingReceivablePriorModificationsNumberofContractsCollected	3	loan
CY2019	us-gaap	Proceeds From Collection Of Loans Receivable ProceedsFromCollectionOfLoansReceivable	81600	USD
CY2019Q4	us-gaap	Financing Receivable Before Allowance For Credit Loss And Fee FinancingReceivableBeforeAllowanceForCreditLossAndFee	14425704000	USD
CY2020Q4	sfnc	Financing Receivable Collateral Dependent Amount FinancingReceivableCollateralDependentAmount	70000000.0	USD
CY2020Q4	sfnc	Financing Receivable Collateral Dependent Amount FinancingReceivableCollateralDependentAmount	69998000	USD
CY2020Q4	us-gaap	Off Balance Sheet Credit Loss Liability OffBalanceSheetCreditLossLiability	22400000	USD
CY2019Q4	us-gaap	Off Balance Sheet Credit Loss Liability OffBalanceSheetCreditLossLiability	8400000	USD
CY2020	us-gaap	Off Balance Sheet Credit Loss Liability Credit Loss Expense Reversal OffBalanceSheetCreditLossLiabilityCreditLossExpenseReversal	-10000000.0	USD
CY2020	us-gaap	Provision For Loan And Lease Losses ProvisionForLoanAndLeaseLosses	82488000	USD
CY2019	us-gaap	Provision For Loan And Lease Losses ProvisionForLoanAndLeaseLosses	43240000	USD
CY2018	us-gaap	Provision For Loan And Lease Losses ProvisionForLoanAndLeaseLosses	38148000	USD
CY2020	sfnc	Provision For Unfunded Commitments ProvisionForUnfundedCommitments	-10000000	USD
CY2020Q4	us-gaap	Operating Lease Liability OperatingLeaseLiability	31433000	USD
CY2019	sfnc	Provision For Unfunded Commitments ProvisionForUnfundedCommitments	0	USD
CY2018	sfnc	Provision For Unfunded Commitments ProvisionForUnfundedCommitments	0	USD
CY2020	us-gaap	Debt Securities Held To Maturity Credit Loss Expense Reversal DebtSecuritiesHeldToMaturityCreditLossExpenseReversal	2546000	USD
CY2019	us-gaap	Debt Securities Held To Maturity Credit Loss Expense Reversal DebtSecuritiesHeldToMaturityCreditLossExpenseReversal	0	USD
CY2018	us-gaap	Debt Securities Held To Maturity Credit Loss Expense Reversal DebtSecuritiesHeldToMaturityCreditLossExpenseReversal	0	USD
CY2020	us-gaap	Debt Securities Available For Sale Change In Present Value Expense Reversal DebtSecuritiesAvailableForSaleChangeInPresentValueExpenseReversal	-61000	USD
CY2019	us-gaap	Debt Securities Available For Sale Change In Present Value Expense Reversal DebtSecuritiesAvailableForSaleChangeInPresentValueExpenseReversal	0	USD
CY2018	us-gaap	Debt Securities Available For Sale Change In Present Value Expense Reversal DebtSecuritiesAvailableForSaleChangeInPresentValueExpenseReversal	0	USD
CY2020	us-gaap	Provision For Loan Lease And Other Losses ProvisionForLoanLeaseAndOtherLosses	74973000	USD
CY2019	us-gaap	Provision For Loan Lease And Other Losses ProvisionForLoanLeaseAndOtherLosses	43240000	USD
CY2018	us-gaap	Provision For Loan Lease And Other Losses ProvisionForLoanLeaseAndOtherLosses	38148000	USD
CY2020Q4	us-gaap	Operating Lease Right Of Use Asset OperatingLeaseRightOfUseAsset	31348000	USD
CY2019Q4	us-gaap	Operating Lease Right Of Use Asset OperatingLeaseRightOfUseAsset	40675000	USD
CY2019Q4	us-gaap	Operating Lease Liability OperatingLeaseLiability	40854000	USD
CY2020Q4	us-gaap	Operating Lease Weighted Average Remaining Lease Term1 OperatingLeaseWeightedAverageRemainingLeaseTerm1	P6Y6M18D
CY2019Q4	us-gaap	Operating Lease Weighted Average Remaining Lease Term1 OperatingLeaseWeightedAverageRemainingLeaseTerm1	P8Y4M13D
CY2020Q4	us-gaap	Operating Lease Weighted Average Discount Rate Percent OperatingLeaseWeightedAverageDiscountRatePercent	0.0309
CY2019Q4	us-gaap	Operating Lease Weighted Average Discount Rate Percent OperatingLeaseWeightedAverageDiscountRatePercent	0.0327
CY2020	us-gaap	Operating Lease Expense OperatingLeaseExpense	13103000	USD
CY2019	us-gaap	Operating Lease Expense OperatingLeaseExpense	13560000	USD
CY2018	us-gaap	Operating Lease Expense OperatingLeaseExpense	13378000	USD
CY2020Q4	us-gaap	Lessee Operating Lease Liability Payments Due Next Twelve Months LesseeOperatingLeaseLiabilityPaymentsDueNextTwelveMonths	9192000	USD
CY2020Q4	us-gaap	Lessee Operating Lease Liability Payments Due Year Two LesseeOperatingLeaseLiabilityPaymentsDueYearTwo	7376000	USD
CY2020Q4	us-gaap	Lessee Operating Lease Liability Payments Due Year Three LesseeOperatingLeaseLiabilityPaymentsDueYearThree	5256000	USD
CY2020Q4	us-gaap	Lessee Operating Lease Liability Payments Due Year Four LesseeOperatingLeaseLiabilityPaymentsDueYearFour	3304000	USD
CY2020Q4	us-gaap	Lessee Operating Lease Liability Payments Due Year Five LesseeOperatingLeaseLiabilityPaymentsDueYearFive	2299000	USD
CY2020Q4	us-gaap	Lessee Operating Lease Liability Payments Due After Year Five LesseeOperatingLeaseLiabilityPaymentsDueAfterYearFive	8000000	USD
CY2020Q4	us-gaap	Lessee Operating Lease Liability Payments Due LesseeOperatingLeaseLiabilityPaymentsDue	35427000	USD
CY2020Q4	us-gaap	Lessee Operating Lease Liability Undiscounted Excess Amount LesseeOperatingLeaseLiabilityUndiscountedExcessAmount	3994000	USD
CY2020Q4	us-gaap	Operating Lease Liability OperatingLeaseLiability	31433000	USD
CY2020Q4	us-gaap	Operating Lease Right Of Use Asset OperatingLeaseRightOfUseAsset	31348000	USD
CY2019Q4	us-gaap	Operating Lease Right Of Use Asset OperatingLeaseRightOfUseAsset	40675000	USD
CY2020Q4	sfnc	Property Plantand Equipmentand Rightof Use Asset Accumulated Depreciationand Amortization PropertyPlantandEquipmentandRightofUseAssetAccumulatedDepreciationandAmortization	140450000	USD
CY2019Q4	sfnc	Property Plantand Equipmentand Rightof Use Asset Accumulated Depreciationand Amortization PropertyPlantandEquipmentandRightofUseAssetAccumulatedDepreciationandAmortization	119865000	USD
CY2020Q4	sfnc	Property Plantand Equipmentand Rightof Use Assetafter Accumulated Depreciationand Amortization PropertyPlantandEquipmentandRightofUseAssetafterAccumulatedDepreciationandAmortization	441692000	USD
CY2019Q4	sfnc	Property Plantand Equipmentand Rightof Use Assetafter Accumulated Depreciationand Amortization PropertyPlantandEquipmentandRightofUseAssetafterAccumulatedDepreciationandAmortization	492384000	USD
CY2020Q4	us-gaap	Goodwill Goodwill	1080000000.00	USD
CY2019Q4	us-gaap	Goodwill Goodwill	1060000000.00	USD
CY2020Q4	us-gaap	Finite Lived Intangible Assets Net FiniteLivedIntangibleAssetsNet	111110000	USD
CY2019Q4	us-gaap	Finite Lived Intangible Assets Net FiniteLivedIntangibleAssetsNet	127340000	USD
CY2020Q4	us-gaap	Finite Lived Intangible Assets Net FiniteLivedIntangibleAssetsNet	111110000	USD
CY2019Q4	us-gaap	Finite Lived Intangible Assets Net FiniteLivedIntangibleAssetsNet	127340000	USD
CY2020Q4	us-gaap	Finite Lived Intangible Assets Amortization Expense Next Twelve Months FiniteLivedIntangibleAssetsAmortizationExpenseNextTwelveMonths	13379000	USD
CY2020Q4	us-gaap	Finite Lived Intangible Assets Amortization Expense Year Two FiniteLivedIntangibleAssetsAmortizationExpenseYearTwo	13327000	USD
CY2020Q4	us-gaap	Finite Lived Intangible Assets Amortization Expense Year Three FiniteLivedIntangibleAssetsAmortizationExpenseYearThree	13044000	USD
CY2020Q4	us-gaap	Finite Lived Intangible Assets Amortization Expense Year Four FiniteLivedIntangibleAssetsAmortizationExpenseYearFour	12141000	USD
CY2020Q4	us-gaap	Finite Lived Intangible Assets Amortization Expense Year Five FiniteLivedIntangibleAssetsAmortizationExpenseYearFive	9557000	USD
CY2020Q4	us-gaap	Finite Lived Intangible Assets Amortization Expense After Year Five FiniteLivedIntangibleAssetsAmortizationExpenseAfterYearFive	49662000	USD
CY2020Q4	us-gaap	Finite Lived Intangible Assets Net FiniteLivedIntangibleAssetsNet	111110000	USD
CY2020Q4	us-gaap	Time Deposits100000 Or More TimeDeposits100000OrMore	2030000000.00	USD
CY2019Q4	us-gaap	Time Deposits100000 Or More TimeDeposits100000OrMore	2150000000	USD
CY2020Q4	us-gaap	Time Deposits At Or Above Fdic Insurance Limit TimeDepositsAtOrAboveFDICInsuranceLimit	889800000	USD
CY2019Q4	us-gaap	Time Deposits At Or Above Fdic Insurance Limit TimeDepositsAtOrAboveFDICInsuranceLimit	837300000	USD
CY2020Q4	us-gaap	Interest Bearing Domestic Deposit Brokered InterestBearingDomesticDepositBrokered	512300000	USD
CY2019Q4	us-gaap	Interest Bearing Domestic Deposit Brokered InterestBearingDomesticDepositBrokered	1060000000.00	USD
CY2020Q4	us-gaap	Time Deposit Maturities Year One TimeDepositMaturitiesYearOne	2426751000	USD
CY2020Q4	us-gaap	Time Deposit Maturities Year Two TimeDepositMaturitiesYearTwo	285555000	USD
CY2020Q4	us-gaap	Time Deposit Maturities Year Three TimeDepositMaturitiesYearThree	98663000	USD
CY2020Q4	us-gaap	Time Deposit Maturities Year Four TimeDepositMaturitiesYearFour	15353000	USD
CY2020Q4	us-gaap	Time Deposit Maturities Year Five TimeDepositMaturitiesYearFive	5851000	USD
CY2020Q4	us-gaap	Time Deposit Maturities After Year Five TimeDepositMaturitiesAfterYearFive	154000	USD
CY2020Q4	us-gaap	Time Deposits TimeDeposits	2832327000	USD
CY2020	us-gaap	Current Income Tax Expense Benefit CurrentIncomeTaxExpenseBenefit	65012000	USD
CY2019	us-gaap	Current Income Tax Expense Benefit CurrentIncomeTaxExpenseBenefit	29354000	USD
CY2018	us-gaap	Current Income Tax Expense Benefit CurrentIncomeTaxExpenseBenefit	41946000	USD
CY2020	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	-122000	USD
CY2019	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	34911000	USD
CY2018	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	8412000	USD
CY2020	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	64890000	USD
CY2019	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	64265000	USD
CY2018	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	50358000	USD
CY2020Q4	sfnc	Deferred Tax Assets Loans Acquired DeferredTaxAssetsLoansAcquired	10100000	USD
CY2020Q4	us-gaap	Long Term Debt Maturities Repayments Of Principal In Year Three LongTermDebtMaturitiesRepaymentsOfPrincipalInYearThree	1758000	USD
CY2019Q4	sfnc	Deferred Tax Assets Tax Deferred Expense Reservesand Accruals Unfunded Commitments DeferredTaxAssetsTaxDeferredExpenseReservesandAccrualsUnfundedCommitments	0	USD
CY2020Q4	us-gaap	Deferred Tax Assets Other DeferredTaxAssetsOther	7600000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Other DeferredTaxAssetsOther	7886000	USD
CY2019Q4	sfnc	Deferred Tax Assets Loans Acquired DeferredTaxAssetsLoansAcquired	20783000	USD
CY2020Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Reserves And Accruals Provision For Loan Losses DeferredTaxAssetsTaxDeferredExpenseReservesAndAccrualsProvisionForLoanLosses	58028000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Reserves And Accruals Provision For Loan Losses DeferredTaxAssetsTaxDeferredExpenseReservesAndAccrualsProvisionForLoanLosses	16732000	USD
CY2020Q4	sfnc	Deberred Tax Assets On Forclosed Assets DeberredTaxAssetsOnForclosedAssets	1673000	USD
CY2019Q4	sfnc	Deberred Tax Assets On Forclosed Assets DeberredTaxAssetsOnForclosedAssets	2626000	USD
CY2020Q4	us-gaap	Deferred Tax Assets Other Loss Carryforwards DeferredTaxAssetsOtherLossCarryforwards	16028000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Other Loss Carryforwards DeferredTaxAssetsOtherLossCarryforwards	18118000	USD
CY2020Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Compensation And Benefits Employee Compensation DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsEmployeeCompensation	3060000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Compensation And Benefits Employee Compensation DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsEmployeeCompensation	2750000	USD
CY2020Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Compensation And Benefits Other DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsOther	5905000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Compensation And Benefits Other DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsOther	6677000	USD
CY2020Q4	sfnc	Deferred Tax Assets Acquired Securities DeferredTaxAssetsAcquiredSecurities	587000	USD
CY2019Q4	sfnc	Deferred Tax Assets Acquired Securities DeferredTaxAssetsAcquiredSecurities	3393000	USD
CY2020Q4	sfnc	Deferred Tax Assets Operating Lease Liabilities DeferredTaxAssetsOperatingLeaseLiabilities	7835000	USD
CY2019Q4	sfnc	Deferred Tax Assets Operating Lease Liabilities DeferredTaxAssetsOperatingLeaseLiabilities	10221000	USD
CY2020Q4	sfnc	Deferred Tax Assets Tax Deferred Expense Reservesand Accruals Unfunded Commitments DeferredTaxAssetsTaxDeferredExpenseReservesandAccrualsUnfundedCommitments	5583000	USD
CY2020Q4	us-gaap	Deferred Tax Assets Gross DeferredTaxAssetsGross	116399000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Gross DeferredTaxAssetsGross	89186000	USD
CY2020Q4	us-gaap	Deferred Tax Liabilities Goodwill And Intangible Assets DeferredTaxLiabilitiesGoodwillAndIntangibleAssets	38882000	USD
CY2019Q4	us-gaap	Deferred Tax Liabilities Goodwill And Intangible Assets DeferredTaxLiabilitiesGoodwillAndIntangibleAssets	41221000	USD
CY2020Q4	us-gaap	Deferred Tax Liabilities Property Plant And Equipment DeferredTaxLiabilitiesPropertyPlantAndEquipment	34667000	USD
CY2019Q4	us-gaap	Deferred Tax Liabilities Property Plant And Equipment DeferredTaxLiabilitiesPropertyPlantAndEquipment	36554000	USD
CY2020Q4	sfnc	Deferred Tax Liabilities Operating Right Of Use Assets DeferredTaxLiabilitiesOperatingRightOfUseAssets	7813000	USD
CY2019Q4	sfnc	Deferred Tax Liabilities Operating Right Of Use Assets DeferredTaxLiabilitiesOperatingRightOfUseAssets	10176000	USD
CY2020Q4	sfnc	Deferred Tax Liabilities Unrealized Gainson Availablefor Sale Securities Gross DeferredTaxLiabilitiesUnrealizedGainsonAvailableforSaleSecuritiesGross	17521000	USD
CY2019Q4	sfnc	Deferred Tax Liabilities Unrealized Gainson Availablefor Sale Securities Gross DeferredTaxLiabilitiesUnrealizedGainsonAvailableforSaleSecuritiesGross	3720000	USD
CY2020Q4	us-gaap	Deferred Tax Liabilities Other DeferredTaxLiabilitiesOther	4021000	USD
CY2019Q4	us-gaap	Deferred Tax Liabilities Other DeferredTaxLiabilitiesOther	7651000	USD
CY2020Q4	us-gaap	Deferred Income Tax Liabilities DeferredIncomeTaxLiabilities	102904000	USD
CY2019Q4	us-gaap	Deferred Income Tax Liabilities DeferredIncomeTaxLiabilities	99322000	USD
CY2020Q4	us-gaap	Deferred Tax Assets Net DeferredTaxAssetsNet	13495000	USD
CY2019Q4	us-gaap	Deferred Tax Liabilities DeferredTaxLiabilities	10136000	USD
CY2020	us-gaap	Income Tax Reconciliation Income Tax Expense Benefit At Federal Statutory Income Tax Rate IncomeTaxReconciliationIncomeTaxExpenseBenefitAtFederalStatutoryIncomeTaxRate	67143000	USD
CY2019	us-gaap	Income Tax Reconciliation Income Tax Expense Benefit At Federal Statutory Income Tax Rate IncomeTaxReconciliationIncomeTaxExpenseBenefitAtFederalStatutoryIncomeTaxRate	63442000	USD
CY2018	us-gaap	Income Tax Reconciliation Income Tax Expense Benefit At Federal Statutory Income Tax Rate IncomeTaxReconciliationIncomeTaxExpenseBenefitAtFederalStatutoryIncomeTaxRate	55875000	USD
CY2020	us-gaap	Income Tax Reconciliation State And Local Income Taxes IncomeTaxReconciliationStateAndLocalIncomeTaxes	6402000	USD
CY2019	us-gaap	Income Tax Reconciliation State And Local Income Taxes IncomeTaxReconciliationStateAndLocalIncomeTaxes	5860000	USD
CY2018	us-gaap	Income Tax Reconciliation State And Local Income Taxes IncomeTaxReconciliationStateAndLocalIncomeTaxes	5015000	USD
CY2020	sfnc	Income Tax Rate Reconciliation Discrete Items Related To Asu201609 IncomeTaxRateReconciliationDiscreteItemsRelatedToASU201609	-375000	USD
CY2019	sfnc	Income Tax Rate Reconciliation Discrete Items Related To Asu201609 IncomeTaxRateReconciliationDiscreteItemsRelatedToASU201609	38000	USD
CY2018	sfnc	Income Tax Rate Reconciliation Discrete Items Related To Asu201609 IncomeTaxRateReconciliationDiscreteItemsRelatedToASU201609	2439000	USD
CY2020	sfnc	Income Tax Rate Reconciliation Tax Exempt Interest Income IncomeTaxRateReconciliationTaxExemptInterestIncome	6726000	USD
CY2019	sfnc	Income Tax Rate Reconciliation Tax Exempt Interest Income IncomeTaxRateReconciliationTaxExemptInterestIncome	4390000	USD
CY2018	sfnc	Income Tax Rate Reconciliation Tax Exempt Interest Income IncomeTaxRateReconciliationTaxExemptInterestIncome	3168000	USD
CY2020	sfnc	Effective Income Tax Rate Reconciliation Dta Remeasurement EffectiveIncomeTaxRateReconciliationDTARemeasurement	-1214000	USD
CY2019	sfnc	Effective Income Tax Rate Reconciliation Dta Remeasurement EffectiveIncomeTaxRateReconciliationDTARemeasurement	-852000	USD
CY2018	sfnc	Effective Income Tax Rate Reconciliation Dta Remeasurement EffectiveIncomeTaxRateReconciliationDTARemeasurement	-869000	USD
CY2020	us-gaap	Income Tax Reconciliation Tax Credits IncomeTaxReconciliationTaxCredits	2177000	USD
CY2019	us-gaap	Income Tax Reconciliation Tax Credits IncomeTaxReconciliationTaxCredits	939000	USD
CY2018	us-gaap	Income Tax Reconciliation Tax Credits IncomeTaxReconciliationTaxCredits	3003000	USD
CY2020	us-gaap	Income Tax Reconciliation Other Adjustments IncomeTaxReconciliationOtherAdjustments	1087000	USD
CY2019	us-gaap	Income Tax Reconciliation Other Adjustments IncomeTaxReconciliationOtherAdjustments	1182000	USD
CY2018	us-gaap	Income Tax Reconciliation Other Adjustments IncomeTaxReconciliationOtherAdjustments	-1053000	USD
CY2020	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	64890000	USD
CY2019	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	64265000	USD
CY2018	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	50358000	USD
CY2020Q4	us-gaap	Financial Assets Sold Under Agreements To Repurchase Gross Including Not Subject To Master Netting Arrangement FinancialAssetsSoldUnderAgreementsToRepurchaseGrossIncludingNotSubjectToMasterNettingArrangement	248900000	USD
CY2019Q4	us-gaap	Financial Assets Sold Under Agreements To Repurchase Gross Including Not Subject To Master Netting Arrangement FinancialAssetsSoldUnderAgreementsToRepurchaseGrossIncludingNotSubjectToMasterNettingArrangement	133200000	USD
CY2020	us-gaap	Schedule Of Repurchase Agreements ScheduleOfRepurchaseAgreements	The remaining contractual maturity of the securities sold under agreements to repurchase in the consolidated balance sheets as of December 31, 2020 and 2019 is presented in the following tables. <table style="border-collapse:collapse;display:inline-table;vertical-align:top;width:100.000%"><tr><td style="width:1.0%"/><td style="width:30.652%"/><td style="width:0.1%"/><td style="width:1.0%"/><td style="width:11.974%"/><td style="width:0.1%"/><td style="width:0.1%"/><td style="width:0.518%"/><td style="width:0.1%"/><td style="width:1.0%"/><td style="width:11.974%"/><td style="width:0.1%"/><td style="width:0.1%"/><td style="width:0.518%"/><td style="width:0.1%"/><td style="width:1.0%"/><td style="width:11.974%"/><td style="width:0.1%"/><td style="width:0.1%"/><td style="width:0.518%"/><td style="width:0.1%"/><td style="width:1.0%"/><td style="width:11.974%"/><td style="width:0.1%"/><td style="width:0.1%"/><td style="width:0.518%"/><td style="width:0.1%"/><td style="width:1.0%"/><td style="width:11.980%"/><td style="width:0.1%"/></tr><tr><td colspan="3" style="padding:2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%"> </span></td><td colspan="27" style="padding:2px 1pt;text-align:center;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">Remaining Contractual Maturity of the Agreements</span></td></tr><tr><td colspan="3" style="padding:2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">(In thousands)</span></td><td colspan="3" style="border-top:1pt solid #000000;padding:2px 1pt;text-align:center;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">Overnight and<br/>Continuous</span></td><td colspan="3" style="border-top:1pt solid #000000;padding:0 1pt"/><td colspan="3" style="border-top:1pt solid #000000;padding:2px 1pt;text-align:center;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">Up to 30 Days</span></td><td colspan="3" style="border-top:1pt solid #000000;padding:0 1pt"/><td colspan="3" style="border-top:1pt solid #000000;padding:2px 1pt;text-align:center;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">30-90 Days</span></td><td colspan="3" style="border-top:1pt solid #000000;padding:0 1pt"/><td colspan="3" style="border-top:1pt solid #000000;padding:2px 1pt;text-align:center;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">Greater than<br/>90 Days</span></td><td colspan="3" style="border-top:1pt solid #000000;padding:0 1pt"/><td colspan="3" style="border-top:1pt solid #000000;padding:2px 1pt;text-align:center;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">Total</span></td></tr><tr><td colspan="3" style="border-top:1pt solid #000000;padding:2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%;text-decoration:underline">December 31, 2020</span></td><td colspan="3" style="border-top:1pt solid #000000;padding:2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%"> </span></td><td colspan="3" style="border-top:1pt solid #000000;padding:0 1pt"/><td colspan="3" style="border-top:1pt solid #000000;padding:2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%"> </span></td><td colspan="3" style="border-top:1pt solid #000000;padding:0 1pt"/><td colspan="3" style="border-top:1pt solid #000000;padding:2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%"> </span></td><td colspan="3" style="border-top:1pt solid #000000;padding:0 1pt"/><td colspan="3" style="border-top:1pt solid #000000;padding:2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%"> </span></td><td colspan="3" style="border-top:1pt solid #000000;padding:0 1pt"/><td colspan="3" style="border-top:1pt solid #000000;padding:2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%"> </span></td></tr><tr><td colspan="3" style="background-color:#ffffff;padding:2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">Repurchase agreements:</span></td><td colspan="3" style="background-color:#ffffff;padding:2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%"> </span></td><td colspan="3" style="background-color:#ffffff;padding:0 1pt"/><td colspan="3" style="background-color:#ffffff;padding:2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%"> </span></td><td colspan="3" style="background-color:#ffffff;padding:0 1pt"/><td colspan="3" style="background-color:#ffffff;padding:2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%"> </span></td><td colspan="3" style="background-color:#ffffff;padding:0 1pt"/><td colspan="3" style="background-color:#ffffff;padding:2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%"> </span></td><td colspan="3" style="background-color:#ffffff;padding:0 1pt"/><td colspan="3" style="background-color:#ffffff;padding:2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%"> </span></td></tr><tr><td colspan="3" style="background-color:#cceeff;padding:2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">U.S. Government agencies</span></td><td style="background-color:#cceeff;padding:2px 0 2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">$</span></td><td style="background-color:#cceeff;padding:2px 0;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">248,861 </span></td><td style="background-color:#cceeff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#cceeff;padding:0 1pt"/><td style="background-color:#cceeff;padding:2px 0 2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">$</span></td><td style="background-color:#cceeff;padding:2px 0;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">— </span></td><td style="background-color:#cceeff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#cceeff;padding:0 1pt"/><td style="background-color:#cceeff;padding:2px 0 2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">$</span></td><td style="background-color:#cceeff;padding:2px 0;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">— </span></td><td style="background-color:#cceeff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#cceeff;padding:0 1pt"/><td style="background-color:#cceeff;padding:2px 0 2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">$</span></td><td style="background-color:#cceeff;padding:2px 0;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">— </span></td><td style="background-color:#cceeff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#cceeff;padding:0 1pt"/><td style="background-color:#cceeff;padding:2px 0 2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">$</span></td><td style="background-color:#cceeff;padding:2px 0;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">248,861 </span></td><td style="background-color:#cceeff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/></tr><tr style="height:14pt"><td colspan="3" style="background-color:#ffffff;padding:0 1pt"/><td colspan="3" style="background-color:#ffffff;border-top:3pt double #000000;padding:0 1pt"/><td colspan="3" style="background-color:#ffffff;padding:0 1pt"/><td colspan="3" style="background-color:#ffffff;border-top:3pt double #000000;padding:0 1pt"/><td colspan="3" style="background-color:#ffffff;padding:0 1pt"/><td colspan="3" style="background-color:#ffffff;border-top:3pt double #000000;padding:0 1pt"/><td colspan="3" style="background-color:#ffffff;padding:0 1pt"/><td colspan="3" style="background-color:#ffffff;border-top:3pt double #000000;padding:0 1pt"/><td colspan="3" style="background-color:#ffffff;padding:0 1pt"/><td colspan="3" style="background-color:#ffffff;border-top:3pt double #000000;padding:0 1pt"/></tr><tr><td colspan="3" style="background-color:#cceeff;padding:2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%;text-decoration:underline">December 31, 2019</span></td><td colspan="3" style="background-color:#cceeff;padding:2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%"> </span></td><td colspan="3" style="background-color:#cceeff;padding:0 1pt"/><td colspan="3" style="background-color:#cceeff;padding:2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%"> </span></td><td colspan="3" style="background-color:#cceeff;padding:0 1pt"/><td colspan="3" style="background-color:#cceeff;padding:2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%"> </span></td><td colspan="3" style="background-color:#cceeff;padding:0 1pt"/><td colspan="3" style="background-color:#cceeff;padding:2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%"> </span></td><td colspan="3" style="background-color:#cceeff;padding:0 1pt"/><td colspan="3" style="background-color:#cceeff;padding:2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%"> </span></td></tr><tr><td colspan="3" style="background-color:#ffffff;padding:2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">Repurchase agreements:</span></td><td colspan="3" style="background-color:#ffffff;padding:2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%"> </span></td><td colspan="3" style="background-color:#ffffff;padding:0 1pt"/><td colspan="3" style="background-color:#ffffff;padding:2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%"> </span></td><td colspan="3" style="background-color:#ffffff;padding:0 1pt"/><td colspan="3" style="background-color:#ffffff;padding:2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%"> </span></td><td colspan="3" style="background-color:#ffffff;padding:0 1pt"/><td colspan="3" style="background-color:#ffffff;padding:2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%"> </span></td><td colspan="3" style="background-color:#ffffff;padding:0 1pt"/><td colspan="3" style="background-color:#ffffff;padding:2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%"> </span></td></tr><tr><td colspan="3" style="background-color:#cceeff;padding:2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">U.S. Government agencies</span></td><td style="background-color:#cceeff;border-bottom:3pt double #000000;padding:2px 0 2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">$</span></td><td style="background-color:#cceeff;border-bottom:3pt double #000000;padding:2px 0;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">133,220 </span></td><td style="background-color:#cceeff;border-bottom:3pt double #000000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#cceeff;padding:0 1pt"/><td style="background-color:#cceeff;border-bottom:3pt double #000000;padding:2px 0 2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">$</span></td><td style="background-color:#cceeff;border-bottom:3pt double #000000;padding:2px 0;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">— </span></td><td style="background-color:#cceeff;border-bottom:3pt double #000000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#cceeff;padding:0 1pt"/><td style="background-color:#cceeff;border-bottom:3pt double #000000;padding:2px 0 2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">$</span></td><td style="background-color:#cceeff;border-bottom:3pt double #000000;padding:2px 0;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">— </span></td><td style="background-color:#cceeff;border-bottom:3pt double #000000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#cceeff;padding:0 1pt"/><td style="background-color:#cceeff;border-bottom:3pt double #000000;padding:2px 0 2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">$</span></td><td style="background-color:#cceeff;border-bottom:3pt double #000000;padding:2px 0;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">— </span></td><td style="background-color:#cceeff;border-bottom:3pt double #000000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#cceeff;padding:0 1pt"/><td style="background-color:#cceeff;border-bottom:3pt double #000000;padding:2px 0 2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">$</span></td><td style="background-color:#cceeff;border-bottom:3pt double #000000;padding:2px 0;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">133,220 </span></td><td style="background-color:#cceeff;border-bottom:3pt double #000000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/></tr></table>
CY2020Q4	us-gaap	Long Term Debt LongTermDebt	1724941000	USD
CY2019Q4	us-gaap	Long Term Debt LongTermDebt	1685859000	USD
CY2020Q4	us-gaap	Advances From Federal Home Loan Banks AdvancesFromFederalHomeLoanBanks	1310000000	USD
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CY2020Q4	us-gaap	Share Based Compensation Shares Authorized Under Stock Option Plans Exercise Price Range Number Of Exercisable Options ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeNumberOfExercisableOptions	658000	shares
CY2020Q4	us-gaap	Sharebased Compensation Shares Authorized Under Stock Option Plans Exercise Price Range Exercisable Options Weighted Average Exercise Price1 SharebasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeExercisableOptionsWeightedAverageExercisePrice1	22.48
CY2020	us-gaap	Allocated Share Based Compensation Expense AllocatedShareBasedCompensationExpense	13197000	USD
CY2019	us-gaap	Allocated Share Based Compensation Expense AllocatedShareBasedCompensationExpense	12921000	USD
CY2018	us-gaap	Allocated Share Based Compensation Expense AllocatedShareBasedCompensationExpense	11227000	USD
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CY2020Q4	us-gaap	Employee Service Share Based Compensation Nonvested Awards Total Compensation Cost Not Yet Recognized Share Based Awards Other Than Options EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedShareBasedAwardsOtherThanOptions	15524000	USD
CY2020	us-gaap	Employee Service Share Based Compensation Nonvested Awards Total Compensation Cost Not Yet Recognized Period For Recognition1 EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedPeriodForRecognition1	P1Y8M12D
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CY2019	us-gaap	Interest Paid Net InterestPaidNet	182541000	USD
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CY2020	us-gaap	Income Taxes Paid IncomeTaxesPaid	47777000	USD
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CY2018	us-gaap	Income Taxes Paid IncomeTaxesPaid	25718000	USD
CY2020	sfnc	Transfer Of Property To Held For Sale TransferOfPropertyToHeldForSale	11200000	USD
CY2019	sfnc	Transfer Of Property To Held For Sale TransferOfPropertyToHeldForSale	0	USD
CY2018	sfnc	Transfer Of Property To Held For Sale TransferOfPropertyToHeldForSale	0	USD
CY2020	us-gaap	Transfer Of Other Real Estate TransferOfOtherRealEstate	4163000	USD
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CY2019	us-gaap	Financing Receivable Reclassification To Held For Sale FinancingReceivableReclassificationToHeldForSale	259939000	USD
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CY2019	us-gaap	Professional Fees ProfessionalFees	16897000	USD
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CY2020	us-gaap	Postage Expense PostageExpense	7538000	USD
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CY2019	us-gaap	Marketing Expense MarketingExpense	16499000	USD
CY2018	us-gaap	Marketing Expense MarketingExpense	8410000	USD
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CY2019	sfnc	Softwareand Technology Expense SoftwareandTechnologyExpense	25146000	USD
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CY2020	us-gaap	Supplies Expense SuppliesExpense	3322000	USD
CY2019	us-gaap	Supplies Expense SuppliesExpense	2322000	USD
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CY2020	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	13495000	USD
CY2019	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	11805000	USD
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CY2019	sfnc	Branch Right Sizing Expense BranchRightSizingExpense	3129000	USD
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CY2019	us-gaap	Other Noninterest Expense OtherNoninterestExpense	138852000	USD
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CY2019Q4	us-gaap	Letters Of Credit Outstanding Amount LettersOfCreditOutstandingAmount	71074000	USD
CY2020	us-gaap	Description Of New Accounting Pronouncements Not Yet Adopted DescriptionOfNewAccountingPronouncementsNotYetAdopted	NEW ACCOUNTING STANDARDS<div><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:700;line-height:120%">Recently Adopted Accounting Standards</span></div><div style="text-align:justify"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%"> </span></div><div style="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">Reference Rate Reform </span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">– In March 2020, the FASB issued ASU No. 2020-04, </span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-style:italic;font-weight:400;line-height:120%">Reference Rate Reform (Topic 848): Facilitation of the Effects of Reference Rate Reform on Financial Reporting</span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%"> (“ASU 2020-04”), which provides relief for companies preparing for discontinuation of interest rates such as the London Interbank Offered Rate (“LIBOR”). LIBOR is a benchmark interest rate referenced in a variety of agreements that are used by numerous entities. After 2021, it is likely that banks will no longer be required to report information that is used to determine LIBOR, and certain LIBOR rates will no longer be published. As a result, LIBOR could be discontinued as a reference rate. Other interest rates used globally could also be discontinued for similar reasons. ASU 2020-04 provides optional expedients and exceptions to contracts, hedging relationships and other transactions affected by reference rate reform. The main provisions for contract modifications include optional relief by allowing the modification as a continuation of the existing contract without additional analysis and other optional expedients regarding embedded features. Optional expedients for hedge accounting permits changes to critical terms of hedging relationships and to the designated benchmark interest rate in a fair value hedge and also provides relief for assessing hedge effectiveness for cash flow hedges. Companies are able to apply ASU 2020-04 immediately; however, the guidance will only be available for a limited time (generally through December 31, 2022). The Company formed a LIBOR Transition Team in 2020 and has created standard LIBOR replacement language for new and modified loan notes and is not offering discontinued rates on new loans. The Company monitors the remaining loans with LIBOR rates monthly to ensure progress. The adoption of ASU 2020-04 has not had a material impact on the Company’s financial position or results of operations. </span></div><div style="text-align:justify"><span><br/></span></div><div style="text-align:justify"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">In January 2021, the FASB issued ASU No. 2021-01, </span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-style:italic;font-weight:400;line-height:120%">Reference Rate Reform (Topic 848): Scope</span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%"> (“ASU 2021-01”), which clarifies that certain optional expedients and exceptions in ASC 848 for contract modifications and hedge accounting apply to derivatives that are affected by the discounting transition. ASU 2021-01 also amends the expedients and exceptions in ASC 848 to capture the incremental consequences of the scope clarification and to tailor the existing guidance to derivative instruments affected by the discounting transition. ASU 2021-01 was effective upon issuance and generally can be applied through December 31, 2022. ASU 2021-01 did not have a material impact on the Company’s financial position or results of operations.</span></div><div style="text-align:justify"><span><br/></span></div><div style="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">Fair Value Measurement Disclosures</span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%"> – In August 2018, the FASB issued Accounting Standards Update (“ASU”) No. 2018-13, </span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-style:italic;font-weight:400;line-height:120%">Fair Value Measurement (Topic 820): Disclosure Framework-Changes to the Disclosure Requirements for Fair Value Measurement</span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%"> (“ASU 2018-13”), that eliminates, amends and adds disclosure requirements for fair value measurements. These amendments are part of FASB’s disclosure review project and they are expected to reduce costs for preparers while providing more decision-useful information for financial statement users. The eliminated disclosure requirements include the 1) the amount of, and reasons for, transfers between Level 1 and Level 2 of the fair value hierarchy; 2) the policy of timing of transfers between levels of the fair value hierarchy; and 3) the valuation processes for Level 3 fair value measurements. Among other modifications, the amended disclosure requirements remove the term “at a minimum” from the phrase “an entity shall disclose at a minimum” to promote the appropriate exercise of discretion by entities and clarifies that the measurement uncertainty disclosure is to communicate information about the uncertainty in measurement as of the reporting date. Under the new disclosure requirements, entities must disclose the changes in unrealized gains or losses included in other comprehensive income for recurring Level 3 fair value measurements held at the end of the reporting period and the range and weighted average used to develop significant unobservable inputs for Level 3 fair value measurements. ASU 2018-13 is effective for fiscal years beginning after December 15, 2019, and interim periods within those fiscal years, with early adoption permitted. ASU 2018-13 did not have a material impact on the Company’s fair value disclosures.</span></div><div style="text-align:justify"><span><br/></span></div><div style="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">Credit Losses on Financial Instruments</span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%"> – In June 2016, the FASB issued ASU No. 2016-13, </span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-style:italic;font-weight:400;line-height:120%">Financial Instruments - Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments</span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%"> (“ASU 2016-13”), which requires earlier measurement of credit losses, expands the range of information considered in determining expected credit losses and enhances disclosures. The main objective of ASU 2016-13 is to provide financial statement users with more decision-useful information about the expected credit losses on financial instruments and other commitments to extend credit held by a reporting entity at each reporting date. The amendments replace the incurred loss impairment methodology in current US GAAP with a methodology (the current expected credit losses, or “CECL”, methodology) that reflects expected credit losses and requires consideration of a broader range of reasonable and supportable information to inform credit loss estimates.</span></div><div style="text-align:justify"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">The CECL methodology utilizes a lifetime “expected credit loss” measurement objective for the recognition of credit losses for loans, held-to-maturity debt securities and other receivables measured at amortized cost at the time the financial asset is originated or acquired. The allowance for credit losses is adjusted each period for changes in expected lifetime credit losses. This methodology replaces the multiple existing impairment methods in current guidance, which generally require that a loss be incurred before it is recognized. Within the life cycle of a loan or other financial asset, this new guidance will generally result in the earlier recognition of the provision for credit losses and the related allowance for credit losses than current practice. For available-for-sale debt securities that the Company intends to hold and where fair value is less than cost, credit-related impairment, if any, will be recognized through an allowance for credit losses and adjusted each period for changes in credit risk. </span></div><div style="text-align:justify"><span><br/></span></div><div style="text-align:justify"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">The effective date for these amendments is for fiscal years beginning after December 15, 2019, including interim periods within those fiscal years. In preparation for implementation of ASU 2016-13, the Company formed a cross functional team that assessed its data and system needs and evaluated the potential impact of adopting the new guidance. The Company anticipated a significant change in the processes and procedures to calculate the loan losses, including changes in assumptions and estimates to consider expected credit losses over the life of the loan versus the prior accounting practice that utilized the incurred loss model. </span></div><div style="text-align:justify"><span><br/></span></div><div style="text-align:justify"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">On March 27, 2020, the CARES Act was signed in to law by the President of the United States and allowed the option to temporarily defer or suspend the adoption of ASU 2016-13. During the deferral, a registrant would continue to use the incurred loss model for the allowance for loan and lease losses and would be in accordance with US GAAP. The Company has not elected to temporarily defer the adoption of ASU 2016-13 and adopted the new standard as of January 1, 2020. Upon adoption, the Company recorded an additional allowance for credit losses on loans of approximately $151.4 million and an adjustment to the reserve for unfunded commitments recorded in other liabilities of $24.0 million. The Company also recorded an additional allowance for credit losses on investment securities of $742,000. The impact at adoption was reflected as an adjustment to beginning retained earnings, net of income taxes, in the amount of $128.1 million. </span></div><div style="text-align:justify"><span><br/></span></div><div style="text-align:justify"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">The significant impact to the Company’s allowance for credit losses at the date of adoption was driven by the substantial amount of loans acquired held by the Company. The Company had approximately one third of total loans categorized as acquired at the adoption date with very little reserve allocated to them due to the previous incurred loss impairment methodology. As such, the amount of the CECL adoption impact was greater on the Company when compared to a non-acquisitive bank.</span></div><div style="text-align:justify"><span><br/></span></div><div style="text-align:justify"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">In December 2018, the Federal Reserve, Office of the Comptroller of the Currency and FDIC (collectively, the “agencies”) issued a final rule revising regulatory capital rules in anticipation of the adoption of ASU 2016-13 that provided an option to phase in over a three year period on a straight line basis the day-one impact on earnings and Tier 1 capital (the “CECL Transition Provision”).</span></div><div style="text-align:justify"><span><br/></span></div><div style="text-align:justify"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">In March 2020 and in response to the COVID-19 pandemic, the agencies issued a new regulatory capital rule revising the CECL Transition Provision to delay the estimated impact on regulatory capital stemming from the implementation of ASU 2016-13. The rule provides banking organizations that implement CECL before the end of 2020 the option to delay for two years an estimate of CECL’s effect on regulatory capital, followed by a three-year transition period (the “2020 CECL Transition Provision”). The Company elected to apply the 2020 CECL Transition Provision.</span></div><div style="text-align:justify"><span><br/></span></div><div style="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">Cloud Computing Arrangements </span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">– In August 2018, the FASB issued ASU No. 2018-15, </span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-style:italic;font-weight:400;line-height:120%">Intangibles-Goodwill and Other-Internal-Use Software (Subtopic 350-40): Customer’s Accounting for Implementation Costs Incurred in a Cloud Computing Arrangement That is a Service Contract</span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%"> (“ASU 2018-15”), that amends the definition of a hosting arrangement and requires a customer in a hosting arrangement that is a service contract to capitalize certain implementation costs as if the arrangement was an internal-use software project. The internal-use software guidance states that only qualifying costs incurred during the application development stage can be capitalized. The effective date is for fiscal years beginning after December 15, 2019, and interim periods within those fiscal years, with early adoption permitted. Entities have the option to apply the guidance prospectively to all implementation costs incurred after the date of adoption or retrospectively in accordance with the applicable guidance. At the time of adoption, entities will be required to disclose the nature of its hosting arrangements that are service contracts and provide disclosures as if the deferred implementation costs were a separate, major depreciable asset class. The Company early adopted ASU 2018-15 in the first quarter 2019 and elected to apply the guidance prospectively to all software implementation costs incurred after the date of adoption. The applicable software implementation costs that have been capitalized subsequent to the adoption of ASU No. 2018-15 have not had a material impact on our financial position or results of operations. </span></div><div style="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">Derivatives and Hedging: Targeted Improvements </span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">- In August 2017, the FASB issued ASU No. 2017-12, </span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-style:italic;font-weight:400;line-height:120%">Derivatives and Hedging (Topic 815): Targeted Improvements to Accounting for Hedging Activities</span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%"> (“ASU 2017-12”), that changes both the designation and measurement guidance for qualifying hedging relationships and the presentation of hedge results in order to better align a company’s risk management activities and financial reporting for hedging relationships. In summary, this amendment 1) expands the types of transactions eligible for hedge accounting; 2) eliminates the separate measurement and presentation of hedge ineffectiveness; 3) simplifies the requirements around the assessment of hedge effectiveness; 4) provides companies more time to finalize hedge documentation; and 5) enhances presentation and disclosure requirements. The effective date was for fiscal years beginning after December 15, 2018, and interim periods within those fiscal years, with early adoption permitted. All transition requirements and elections should be applied to existing hedging relationships on the date of adoption and the effects should be reflected as of the beginning of the fiscal year of adoption. As part of this new guidance, entities are allowed to designate as the hedged item, an amount that is not expected to be affected by prepayments, defaults or other events affecting the timing and amount of cash flows in a closed portfolio of prepayable financial instruments (this is referred to as the “last-of-layer” method). Under the last-of-layer method, entities are able to reclassify, only at the time of adoption, eligible callable debt securities from held-to-maturity to available-for-sale without tainting its intentions to hold future debt securities to maturity. The available-for-sale security must be reported at fair value and any unrealized gain or loss must be recorded as an adjustment to other comprehensive income upon adoption. The Company evaluated its held-to-maturity portfolio during the first quarter 2019 and identified certain municipal bonds with a fair value of $216.4 million that met the last-of-layer criteria under ASU 2017-12 and as a result, reclassified those to available-for-sale and recorded an unrealized gain of $2.5 million in accumulated other comprehensive income during the first quarter of 2019. </span></div><div style="text-align:justify"><span><br/></span></div><div style="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">Goodwill Impairment</span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%"> – In January 2017, the FASB issued ASU No. 2017-04, </span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-style:italic;font-weight:400;line-height:120%">Intangibles – Goodwill and Other (Topic 350): Simplifying the Test for Goodwill Impairment</span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%"> (“ASU 2017-04”), that eliminates Step 2 from the goodwill impairment test which required entities to compare the implied fair value of goodwill to its carrying amount. Under the amendments, the goodwill impairment will be measured as the excess of the reporting unit’s carrying amount over its fair value. An impairment charge should be recognized for the amount by which the carrying amount exceeds the reporting unit’s fair value; however, the loss recognized should not exceed the total amount of goodwill allocated to that reporting unit. The effective date is for fiscal years beginning after December 15, 2019, with early adoption permitted for interim or annual impairment tests beginning in 2017. The Company early adopted ASU 2017-04 during the second quarter of 2019 to coincide with the Company’s formal impairment analysis. See Note 8, Goodwill and Other Intangible Assets, for additional information.</span></div><div><span><br/></span></div><div style="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">Leases </span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">- In February 2016, the FASB issued ASU No. 2016-02, </span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-style:italic;font-weight:400;line-height:120%">Leases (Topic 842)</span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%"> (“ASU 2016-02”), that establishes the principles to report transparent and economically neutral information about the assets and liabilities that arise from leases. The new guidance results in a more consistent representation of the rights and obligations arising from leases by requiring lessees to recognize the lease asset and lease liabilities that arise from leases in the consolidated balance sheet and to disclose qualitative and quantitative information about lease transactions, such as information about variable lease payments and options to renew and terminate leases. The effective date was for fiscal years beginning after December 15, 2018, including interim periods within those fiscal years. ASU 2016-02 requires entities to adopt the new lease standard using a modified retrospective transition method, meaning an entity initially applies the new lease standard at the beginning of the earliest period presented in the financial statements. Due to complexities associated with using this method, in July 2018, the FASB issued ASU No. 2018-11, </span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-style:italic;font-weight:400;line-height:120%">Leases (Topic 842): Targeted Improvements</span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">, to relieve entities of the requirement to present prior comparative years’ results when they adopt the new lease standard and giving entities the option to recognize the cumulative effect of applying the new standard as an adjustment to the opening balance of retained earnings. Adoption of ASU 2016-02 resulted in the recognition of right-of-use assets of $32.8 million and right-of-use liabilities of $32.8 million on the consolidated balance sheet with no material impact to the results of operations. The Company has elected to adopt the guidance using the optional transition method, which allows for a modified retrospective method of adoption with a cumulative effect adjustment to retained earnings without restating comparable periods. The Company also elected the relief package of practical expedients for which there is no requirement to reassess existence of leases, their classification, and initial direct costs as well as an exemption for short-term leases with a term of less than one year, whereby the Company did not recognize a lease liability or right-of-use asset on the consolidated balance sheet but instead will recognize lease payments as an expense over the lease term as appropriate. See Note 6, Right-of-Use Lease Assets and Lease Liabilities, for additional information related to the Company’s right-of-use lease obligations.</span></div><div><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:700;line-height:120%">Recently Issued Accounting Standards</span></div><div style="text-align:justify"><span><br/></span></div><div style="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">Income Taxes</span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%"> – In December 2019, the FASB issued ASU No. 2019-12, </span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-style:italic;font-weight:400;line-height:120%">Income Taxes (Topic 740): Simplifying the Accounting for Income Taxes</span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%"> (“ASU 2019-12”), that removes certain exceptions for investments, intraperiod allocations and interim calculations, and adds guidance to reduce complexity in accounting for income taxes. ASU 2019-12 introduces the following new guidance: i) guidance to evaluate whether a step-up in tax basis of goodwill relates to a business combination in which book goodwill was recognized or a separate transaction and ii) a policy election to not allocate consolidated income taxes when a member of a consolidated tax return is not subject to income tax. Additionally, ASU 2019-12 changes the following current guidance: i) making an intraperiod allocation, if there is a loss in continuing operations and gains outside of continuing operations, ii) determining when a deferred tax liability is recognized after an investor in a foreign entity transitions to or from the equity method of accounting, iii) accounting for tax law changes and year-to-date losses in interim periods, and iv) determining how to apply the income tax guidance to franchise taxes that are partially based on income. ASU 2019-12 is effective for fiscal years, and interim periods within those fiscal years, beginning after December 15, 2020, with early adoption permitted. The adoption of ASU 2019-12 is not expected to have a material impact on the Company’s operations, financial position or disclosures.</span></div><div><span><br/></span></div><div style="text-align:justify"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">Presently, the Company is not aware of any other changes to the Accounting Standards Codification that will have a material impact on the Company’s present or future financial position or results of operations.</span></div>
CY2020Q4	us-gaap	Statutory Accounting Practices Statutory Amount Available For Dividend Payments Without Regulatory Approval StatutoryAccountingPracticesStatutoryAmountAvailableForDividendPaymentsWithoutRegulatoryApproval	45600000	USD
CY2020	us-gaap	Net Income Loss NetIncomeLoss	254904000	USD
CY2019	us-gaap	Net Income Loss NetIncomeLoss	238167000	USD
CY2018	us-gaap	Net Income Loss NetIncomeLoss	215713000	USD

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2020 Q4 Form 10-K Financial Statement

#000162828021003318 Filed on February 25, 2021

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2020 Q4 Form 10-K Financial Statement

#000162828021003318 Filed on February 25, 2021

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Simmons First National Corp Stock $sfnc