$CBSH
COMMERCE BANCSHARES INC /MO/ Stock $cbsh

$cbsh Overview Financials Valuation SEC Filings Company Website

2021 Q4 Form 10-Q Financial Statement

#000002235621000046 Filed on November 05, 2021

Income Statement

Concept	2021 Q4	2021 Q3	2020 Q3
Revenue		$0.00	$0.00
YoY Change
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	$11.30M	$11.10M	$11.20M
YoY Change	0.0%	-0.89%	7.69%
% of Gross Profit
Operating Expenses
YoY Change
Operating Profit
YoY Change
Interest Expense		$2.944M	$7.152M
YoY Change		-58.84%	-74.67%
% of Operating Profit
Other Income/Expense, Net
YoY Change
Pretax Income	$149.1M	$160.4M	$167.7M
YoY Change	-9.8%	-4.36%	20.51%
Income Tax	$33.80M	$34.66M	$34.38M
% Of Pretax Income	22.67%	21.61%	20.49%
Net Earnings	$114.9M	$122.6M	$132.4M
YoY Change	-11.55%	-7.46%	21.24%
Net Earnings / Revenue
Basic Earnings Per Share		$1.05	$1.06
Diluted Earnings Per Share	$948.0K	$1.05	$1.06
COMMON SHARES
Basic Shares Outstanding	116.2M shares	116.8M shares	111.5M shares
Diluted Shares Outstanding

Balance Sheet

Concept	2021 Q4	2021 Q3	2020 Q3
SHORT-TERM ASSETS
Cash & Short-Term Investments
YoY Change
Cash & Equivalents	$4.297B	$2.252B	$1.557B
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	$388.7M	$377.5M	$377.9M
YoY Change	4.76%	-0.1%	3.25%
Goodwill	$138.9M	$138.9M	$138.9M
YoY Change	0.0%	0.0%	0.0%
Intangibles	$15.57M	$14.46M	$7.183M
YoY Change	38.93%	101.28%	-21.4%
Long-Term Investments	$1.834M	$1.834M
YoY Change	-89.81%
Other Assets
YoY Change
Total Long-Term Assets
YoY Change
TOTAL ASSETS
Total Short-Term Assets
Total Long-Term Assets
Total Assets	$36.69B	$34.50B	$31.45B
YoY Change	11.44%	9.68%	21.55%
SHORT-TERM LIABILITIES
YoY Change
Accounts Payable
YoY Change
Accrued Expenses
YoY Change
Deferred Revenue
YoY Change
Short-Term Debt	$3.023B	$2.254B	$1.653B
YoY Change	44.09%	36.36%	0.73%
Long-Term Debt Due
YoY Change
Total Short-Term Liabilities	$3.023B	$2.254B	$1.653B
YoY Change	44.09%	36.36%	6022.22%
LONG-TERM LIABILITIES
Long-Term Debt	$13.00M	$4.000M	$1.000M
YoY Change	1200.0%	300.0%	-99.61%
Other Long-Term Liabilities	$392.0M	$602.0M	$792.0M
YoY Change	-17.82%	-23.99%	48.04%
Total Long-Term Liabilities	$405.0M	$606.0M	$793.0M
YoY Change	-15.27%	-23.58%	0.13%
TOTAL LIABILITIES
Total Short-Term Liabilities	$3.023B	$2.254B	$1.653B
Total Long-Term Liabilities	$405.0M	$606.0M	$793.0M
Total Liabilities	$33.24B	$31.01B	$28.15B
YoY Change	12.59%	10.16%	23.61%
SHAREHOLDERS EQUITY
Retained Earnings	$92.49M	$396.7M	$326.9M
YoY Change	26.7%	21.34%	-29.43%
Common Stock	$610.8M	$589.4M	$564.0M
YoY Change	3.64%	4.5%	0.81%
Preferred Stock
YoY Change
Treasury Stock (at cost)	$32.97M	$92.05M	$69.05M
YoY Change	0.01%	33.3%	-72.56%
Treasury Stock Shares	476.4K shares	1.303M shares	1.041M shares
Shareholders Equity	$3.437B	$3.481B	$3.306B
YoY Change
Total Liabilities & Shareholders Equity	$36.69B	$34.50B	$31.45B
YoY Change	11.44%	9.68%	21.55%

Cashflow Statement

Concept	2021 Q4	2021 Q3	2020 Q3
OPERATING ACTIVITIES
Net Income	$114.9M	$122.6M	$132.4M
YoY Change	-11.55%	-7.46%	21.24%
Depreciation, Depletion And Amortization	$11.30M	$11.10M	$11.20M
YoY Change	0.0%	-0.89%	7.69%
Cash From Operating Activities	$111.6M	$158.9M	$242.7M
YoY Change	-26.39%	-34.53%	93.23%
INVESTING ACTIVITIES
Capital Expenditures	-$19.30M	-$15.50M	-$15.50M
YoY Change	394.87%	0.0%	70.33%
Acquisitions
YoY Change
Other Investing Activities	-$434.6M	-$917.2M	-$1.488B
YoY Change	-53.94%	-38.36%	400.84%
Cash From Investing Activities	-$454.0M	-$932.6M	-$1.503B
YoY Change	-52.09%	-37.97%	390.83%
FINANCING ACTIVITIES
Cash Dividend Paid
YoY Change
Common Stock Issuance & Retirement, Net
YoY Change
Debt Paid & Issued, Net
YoY Change
Cash From Financing Activities	2.388B	479.0M	1.000B
YoY Change	65.04%	-52.1%	865.35%
NET CHANGE
Cash From Operating Activities	111.6M	158.9M	242.7M
Cash From Investing Activities	-454.0M	-932.6M	-1.503B
Cash From Financing Activities	2.388B	479.0M	1.000B
Net Change In Cash	2.045B	-294.7M	-260.6M
YoY Change	214.29%	13.09%	238.0%
FREE CASH FLOW
Cash From Operating Activities	$111.6M	$158.9M	$242.7M
Capital Expenditures	-$19.30M	-$15.50M	-$15.50M
Free Cash Flow	$130.9M	$174.4M	$258.2M
YoY Change	-15.82%	-32.46%	91.69%

Facts In Submission

Frame	Concept Type	Concept / XBRL Key	Value	Unit
	dei	Entity Central Index Key EntityCentralIndexKey	0000022356
CY2021Q4	dei	Entity Common Stock Shares Outstanding EntityCommonStockSharesOutstanding	116171392	shares
	dei	Current Fiscal Year End Date CurrentFiscalYearEndDate	--12-31
	dei	Document Fiscal Year Focus DocumentFiscalYearFocus	2021
	dei	Document Fiscal Period Focus DocumentFiscalPeriodFocus	Q3
	dei	Amendment Flag AmendmentFlag	false
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	us-gaap	Preferred Stock Dividends Per Share Cash Paid PreferredStockDividendsPerShareCashPaid	0
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CY2021Q3	cbsh	Capitalized Interest Or Dividends CapitalizedInterestOrDividends	0	USD
CY2021Q3	cbsh	Purchase Of Risk Participation Agreement PurchaseOfRiskParticipationAgreement	0	USD
CY2020Q3	cbsh	Capitalized Interest Or Dividends CapitalizedInterestOrDividends	0	USD
CY2020Q3	cbsh	Purchase Of Risk Participation Agreement PurchaseOfRiskParticipationAgreement	0	USD
CY2020Q3	cbsh	Sale Of Risk Participation Agreement SaleOfRiskParticipationAgreement	0	USD
	cbsh	Purchase Of Risk Participation Agreement PurchaseOfRiskParticipationAgreement	0	USD
CY2020Q3	cbsh	Long Lived Assets Nonrecurring Basis LongLivedAssetsNonrecurringBasis	0	USD
	cbsh	Long Lived Assets Nonrecurring Basis Gains Losses LongLivedAssetsNonrecurringBasisGainsLosses	0	USD
	dei	Document Type DocumentType	10-Q
	dei	Document Quarterly Report DocumentQuarterlyReport	true
	dei	Document Period End Date DocumentPeriodEndDate	2021-09-30
	dei	Document Transition Report DocumentTransitionReport	false
	dei	Entity File Number EntityFileNumber	001-36502
	dei	Entity Registrant Name EntityRegistrantName	COMMERCE BANCSHARES, INC.
	dei	Entity Incorporation State Country Code EntityIncorporationStateCountryCode	MO
	dei	Entity Tax Identification Number EntityTaxIdentificationNumber	43-0889454
	dei	Entity Address Address Line1 EntityAddressAddressLine1	1000 Walnut
	dei	Entity Address City Or Town EntityAddressCityOrTown	Kansas City,
	dei	Entity Address State Or Province EntityAddressStateOrProvince	MO
	dei	Entity Address Postal Zip Code EntityAddressPostalZipCode	64106
	dei	City Area Code CityAreaCode	816
	dei	Local Phone Number LocalPhoneNumber	234-2000
	dei	Security12b Title Security12bTitle	$5 Par Value Common Stock
	dei	Trading Symbol TradingSymbol	CBSH
	dei	Security Exchange Name SecurityExchangeName	NASDAQ
	dei	Entity Current Reporting Status EntityCurrentReportingStatus	Yes
	dei	Entity Interactive Data Current EntityInteractiveDataCurrent	Yes
	dei	Entity Filer Category EntityFilerCategory	Large Accelerated Filer
	dei	Entity Small Business EntitySmallBusiness	false
	dei	Entity Emerging Growth Company EntityEmergingGrowthCompany	false
	dei	Entity Shell Company EntityShellCompany	false
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CY2021Q3	us-gaap	Provision For Loan And Lease Losses ProvisionForLoanAndLeaseLosses	-7385000	USD
CY2020Q3	us-gaap	Provision For Loan And Lease Losses ProvisionForLoanAndLeaseLosses	3101000	USD
	us-gaap	Provision For Loan And Lease Losses ProvisionForLoanAndLeaseLosses	-59272000	USD
	us-gaap	Provision For Loan And Lease Losses ProvisionForLoanAndLeaseLosses	141593000	USD
CY2021Q3	us-gaap	Interest Income Expense After Provision For Loan Loss InterestIncomeExpenseAfterProvisionForLoanLoss	221422000	USD
CY2020Q3	us-gaap	Interest Income Expense After Provision For Loan Loss InterestIncomeExpenseAfterProvisionForLoanLoss	212861000	USD
	us-gaap	Interest Income Expense After Provision For Loan Loss InterestIncomeExpenseAfterProvisionForLoanLoss	687039000	USD
	us-gaap	Interest Income Expense After Provision For Loan Loss InterestIncomeExpenseAfterProvisionForLoanLoss	478491000	USD
CY2021Q3	cbsh	Bank Card Transaction Fees BankCardTransactionFees	42815000	USD
CY2020Q3	cbsh	Bank Card Transaction Fees BankCardTransactionFees	37873000	USD
	cbsh	Bank Card Transaction Fees BankCardTransactionFees	123118000	USD
	cbsh	Bank Card Transaction Fees BankCardTransactionFees	111818000	USD
CY2021Q3	cbsh	Trustfeerevenue Trustfeerevenue	48950000	USD
CY2020Q3	cbsh	Trustfeerevenue Trustfeerevenue	40769000	USD
	cbsh	Trustfeerevenue Trustfeerevenue	139334000	USD
	cbsh	Trustfeerevenue Trustfeerevenue	118676000	USD
CY2021Q3	cbsh	Depositfeerevenue Depositfeerevenue	25161000	USD
CY2020Q3	cbsh	Depositfeerevenue Depositfeerevenue	23107000	USD
	cbsh	Depositfeerevenue Depositfeerevenue	71724000	USD
	cbsh	Depositfeerevenue Depositfeerevenue	69063000	USD
CY2021Q3	us-gaap	Noninterest Income Other NoninterestIncomeOther	3794000	USD
CY2020Q3	us-gaap	Noninterest Income Other NoninterestIncomeOther	3194000	USD
	us-gaap	Noninterest Income Other NoninterestIncomeOther	12102000	USD
	us-gaap	Noninterest Income Other NoninterestIncomeOther	10756000	USD
CY2021Q3	us-gaap	Brokerage Commissions Revenue BrokerageCommissionsRevenue	4900000	USD
CY2020Q3	us-gaap	Brokerage Commissions Revenue BrokerageCommissionsRevenue	4011000	USD
	us-gaap	Brokerage Commissions Revenue BrokerageCommissionsRevenue	13484000	USD
	us-gaap	Brokerage Commissions Revenue BrokerageCommissionsRevenue	11099000	USD
CY2021Q3	cbsh	Loan Fees And Sales LoanFeesAndSales	6842000	USD
CY2020Q3	cbsh	Loan Fees And Sales LoanFeesAndSales	9769000	USD
	cbsh	Loan Fees And Sales LoanFeesAndSales	24472000	USD
	cbsh	Loan Fees And Sales LoanFeesAndSales	17653000	USD
CY2021Q3	us-gaap	Noninterest Income Other Operating Income NoninterestIncomeOtherOperatingIncome	5044000	USD
CY2020Q3	us-gaap	Noninterest Income Other Operating Income NoninterestIncomeOtherOperatingIncome	10849000	USD
	us-gaap	Noninterest Income Other Operating Income NoninterestIncomeOtherOperatingIncome	28460000	USD
	us-gaap	Noninterest Income Other Operating Income NoninterestIncomeOtherOperatingIncome	31685000	USD
CY2021Q3	us-gaap	Noninterest Income NoninterestIncome	137506000	USD
CY2020Q3	us-gaap	Noninterest Income NoninterestIncome	129572000	USD
	us-gaap	Noninterest Income NoninterestIncome	412694000	USD
	us-gaap	Noninterest Income NoninterestIncome	370750000	USD
CY2021Q3	us-gaap	Gain Loss On Investments GainLossOnInvestments	13108000	USD
CY2020Q3	us-gaap	Gain Loss On Investments GainLossOnInvestments	16155000	USD
	us-gaap	Gain Loss On Investments GainLossOnInvestments	39765000	USD
	us-gaap	Gain Loss On Investments GainLossOnInvestments	-1275000	USD
CY2021Q3	us-gaap	Labor And Related Expense LaborAndRelatedExpense	132824000	USD
CY2020Q3	us-gaap	Labor And Related Expense LaborAndRelatedExpense	127308000	USD
	us-gaap	Labor And Related Expense LaborAndRelatedExpense	392608000	USD
	us-gaap	Labor And Related Expense LaborAndRelatedExpense	383004000	USD
CY2021Q3	us-gaap	Occupancy Net OccupancyNet	12329000	USD
CY2020Q3	us-gaap	Occupancy Net OccupancyNet	12058000	USD
	us-gaap	Occupancy Net OccupancyNet	35877000	USD
	us-gaap	Occupancy Net OccupancyNet	35075000	USD
CY2021Q3	us-gaap	Equipment Expense EquipmentExpense	4440000	USD
CY2020Q3	us-gaap	Equipment Expense EquipmentExpense	4737000	USD
	us-gaap	Equipment Expense EquipmentExpense	13398000	USD
	us-gaap	Equipment Expense EquipmentExpense	14313000	USD
CY2021Q3	cbsh	Supplies Postage And Communication SuppliesPostageAndCommunication	4530000	USD
CY2020Q3	cbsh	Supplies Postage And Communication SuppliesPostageAndCommunication	4141000	USD
	cbsh	Supplies Postage And Communication SuppliesPostageAndCommunication	12688000	USD
	cbsh	Supplies Postage And Communication SuppliesPostageAndCommunication	13226000	USD
CY2021Q3	us-gaap	Information Technology And Data Processing InformationTechnologyAndDataProcessing	25598000	USD
CY2020Q3	us-gaap	Information Technology And Data Processing InformationTechnologyAndDataProcessing	23610000	USD
	us-gaap	Information Technology And Data Processing InformationTechnologyAndDataProcessing	76015000	USD
	us-gaap	Information Technology And Data Processing InformationTechnologyAndDataProcessing	71002000	USD
CY2021Q3	us-gaap	Marketing Expense MarketingExpense	5623000	USD
CY2020Q3	us-gaap	Marketing Expense MarketingExpense	4926000	USD
	us-gaap	Marketing Expense MarketingExpense	16461000	USD
	us-gaap	Marketing Expense MarketingExpense	14706000	USD
CY2021Q3	us-gaap	Other Noninterest Expense OtherNoninterestExpense	26276000	USD
CY2020Q3	us-gaap	Other Noninterest Expense OtherNoninterestExpense	14078000	USD
	us-gaap	Other Noninterest Expense OtherNoninterestExpense	55272000	USD
	us-gaap	Other Noninterest Expense OtherNoninterestExpense	40742000	USD
CY2021Q3	us-gaap	Noninterest Expense NoninterestExpense	211620000	USD
CY2020Q3	us-gaap	Noninterest Expense NoninterestExpense	190858000	USD
	us-gaap	Noninterest Expense NoninterestExpense	602319000	USD
	us-gaap	Noninterest Expense NoninterestExpense	572068000	USD
CY2021Q3	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	160416000	USD
CY2020Q3	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	167730000	USD
	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	537179000	USD
	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	275898000	USD
CY2021Q3	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	34662000	USD
CY2020Q3	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	34375000	USD
	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	111947000	USD
	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	54209000	USD
CY2021Q3	us-gaap	Profit Loss ProfitLoss	125754000	USD
CY2020Q3	us-gaap	Profit Loss ProfitLoss	133355000	USD
	us-gaap	Profit Loss ProfitLoss	425232000	USD
	us-gaap	Profit Loss ProfitLoss	221689000	USD
CY2021Q3	us-gaap	Net Income Loss Attributable To Noncontrolling Interest NetIncomeLossAttributableToNoncontrollingInterest	3193000	USD
CY2020Q3	us-gaap	Net Income Loss Attributable To Noncontrolling Interest NetIncomeLossAttributableToNoncontrollingInterest	907000	USD
	us-gaap	Net Income Loss Attributable To Noncontrolling Interest NetIncomeLossAttributableToNoncontrollingInterest	9373000	USD
	us-gaap	Net Income Loss Attributable To Noncontrolling Interest NetIncomeLossAttributableToNoncontrollingInterest	-2479000	USD
CY2021Q3	us-gaap	Net Income Loss NetIncomeLoss	122561000	USD
CY2020Q3	us-gaap	Net Income Loss NetIncomeLoss	132448000	USD
	us-gaap	Net Income Loss NetIncomeLoss	415859000	USD
	us-gaap	Net Income Loss NetIncomeLoss	224168000	USD
CY2021Q3	us-gaap	Preferred Stock Dividends Income Statement Impact PreferredStockDividendsIncomeStatementImpact	0	USD
CY2020Q3	us-gaap	Preferred Stock Dividends Income Statement Impact PreferredStockDividendsIncomeStatementImpact	7466000	USD
	us-gaap	Preferred Stock Dividends Income Statement Impact PreferredStockDividendsIncomeStatementImpact	0	USD
	us-gaap	Preferred Stock Dividends Income Statement Impact PreferredStockDividendsIncomeStatementImpact	11966000	USD
CY2021Q3	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	122561000	USD
CY2020Q3	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	124982000	USD
	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	415859000	USD
	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	212202000	USD
CY2021Q3	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	1.05
CY2020Q3	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	1.06
	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	3.55
	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	1.80
CY2021Q3	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	1.05
CY2020Q3	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	1.06
	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	3.54
	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	1.80
CY2021Q3	us-gaap	Profit Loss ProfitLoss	125754000	USD
CY2020Q3	us-gaap	Profit Loss ProfitLoss	133355000	USD
	us-gaap	Profit Loss ProfitLoss	425232000	USD
	us-gaap	Profit Loss ProfitLoss	221689000	USD
CY2021Q3	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Net Of Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodNetOfTax	-57068000	USD
CY2020Q3	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Net Of Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodNetOfTax	330000	USD
	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Net Of Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodNetOfTax	-160019000	USD
	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Net Of Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodNetOfTax	165464000	USD
CY2021Q3	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Adjustment Net Of Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentNetOfTax	-451000	USD
CY2020Q3	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Adjustment Net Of Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentNetOfTax	-327000	USD
	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Adjustment Net Of Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentNetOfTax	-1326000	USD
	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Adjustment Net Of Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentNetOfTax	-1038000	USD
CY2021Q3	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss After Reclassification And Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossAfterReclassificationAndTax	-4607000	USD
CY2020Q3	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss After Reclassification And Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossAfterReclassificationAndTax	-6483000	USD
	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss After Reclassification And Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossAfterReclassificationAndTax	-13518000	USD
	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss After Reclassification And Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossAfterReclassificationAndTax	66489000	USD
CY2021Q3	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	-61224000	USD
CY2020Q3	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	-5826000	USD
	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	-172211000	USD
	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	232991000	USD
CY2021Q3	us-gaap	Comprehensive Income Net Of Tax Including Portion Attributable To Noncontrolling Interest ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest	64530000	USD
CY2020Q3	us-gaap	Comprehensive Income Net Of Tax Including Portion Attributable To Noncontrolling Interest ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest	127529000	USD
	us-gaap	Comprehensive Income Net Of Tax Including Portion Attributable To Noncontrolling Interest ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest	253021000	USD
	us-gaap	Comprehensive Income Net Of Tax Including Portion Attributable To Noncontrolling Interest ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest	454680000	USD
CY2021Q3	us-gaap	Comprehensive Income Net Of Tax Attributable To Noncontrolling Interest ComprehensiveIncomeNetOfTaxAttributableToNoncontrollingInterest	3193000	USD
CY2020Q3	us-gaap	Comprehensive Income Net Of Tax Attributable To Noncontrolling Interest ComprehensiveIncomeNetOfTaxAttributableToNoncontrollingInterest	907000	USD
	us-gaap	Comprehensive Income Net Of Tax Attributable To Noncontrolling Interest ComprehensiveIncomeNetOfTaxAttributableToNoncontrollingInterest	9373000	USD
	us-gaap	Comprehensive Income Net Of Tax Attributable To Noncontrolling Interest ComprehensiveIncomeNetOfTaxAttributableToNoncontrollingInterest	-2479000	USD
CY2021Q3	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	61337000	USD
CY2020Q3	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	126622000	USD
	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	243648000	USD
	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	457159000	USD
CY2021Q2	us-gaap	Stockholders Equity Including Portion Attributable To Noncontrolling Interest StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest	3493830000	USD
CY2021Q3	us-gaap	Profit Loss ProfitLoss	125754000	USD
CY2021Q3	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	-61224000	USD
CY2021Q3	us-gaap	Minority Interest Decrease From Distributions To Noncontrolling Interest Holders MinorityInterestDecreaseFromDistributionsToNoncontrollingInterestHolders	193000	USD
CY2021Q3	us-gaap	Treasury Stock Value Acquired Cost Method TreasuryStockValueAcquiredCostMethod	40165000	USD
CY2021Q3	us-gaap	Noncontrolling Interest Increase From Sale Of Parent Equity Interest NoncontrollingInterestIncreaseFromSaleOfParentEquityInterest	0	USD
CY2021Q3	us-gaap	Stock Issued During Period Value Share Based Compensation StockIssuedDuringPeriodValueShareBasedCompensation	-1000	USD
CY2021Q3	us-gaap	Adjustments To Additional Paid In Capital Sharebased Compensation Requisite Service Period Recognition Value AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue	3865000	USD
CY2021Q3	us-gaap	Common Stock Dividends Per Share Cash Paid CommonStockDividendsPerShareCashPaid	0.263
CY2021Q3	us-gaap	Dividends Common Stock Cash DividendsCommonStockCash	30645000	USD
CY2021Q3	us-gaap	Stockholders Equity Including Portion Attributable To Noncontrolling Interest StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest	3491221000	USD
CY2020Q2	us-gaap	Stockholders Equity Including Portion Attributable To Noncontrolling Interest StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest	3358169000	USD
CY2020Q3	us-gaap	Profit Loss ProfitLoss	133355000	USD
CY2020Q3	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	-5826000	USD
CY2020Q3	us-gaap	Minority Interest Decrease From Distributions To Noncontrolling Interest Holders MinorityInterestDecreaseFromDistributionsToNoncontrollingInterestHolders	608000	USD
CY2020Q3	us-gaap	Stock Redeemed Or Called During Period Value StockRedeemedOrCalledDuringPeriodValue	-150000000	USD
CY2020Q3	us-gaap	Treasury Stock Value Acquired Cost Method TreasuryStockValueAcquiredCostMethod	167000	USD
CY2020Q3	us-gaap	Stock Issued During Period Value Share Based Compensation StockIssuedDuringPeriodValueShareBasedCompensation	0	USD
CY2020Q3	us-gaap	Adjustments To Additional Paid In Capital Sharebased Compensation Requisite Service Period Recognition Value AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue	3765000	USD
CY2020Q3	us-gaap	Common Stock Dividends Per Share Cash Paid CommonStockDividendsPerShareCashPaid	0.257
CY2020Q3	us-gaap	Dividends Common Stock Cash DividendsCommonStockCash	30174000	USD
CY2020Q3	us-gaap	Preferred Stock Dividends Per Share Cash Paid PreferredStockDividendsPerShareCashPaid	0.375
CY2020Q3	us-gaap	Dividends Preferred Stock Cash DividendsPreferredStockCash	2250000	USD
CY2020Q3	us-gaap	Stockholders Equity Including Portion Attributable To Noncontrolling Interest StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest	3306264000	USD
CY2020Q4	us-gaap	Stockholders Equity Including Portion Attributable To Noncontrolling Interest StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest	3399972000	USD
	us-gaap	Profit Loss ProfitLoss	425232000	USD
	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	-172211000	USD
	us-gaap	Minority Interest Decrease From Distributions To Noncontrolling Interest Holders MinorityInterestDecreaseFromDistributionsToNoncontrollingInterestHolders	1088000	USD
	us-gaap	Treasury Stock Value Acquired Cost Method TreasuryStockValueAcquiredCostMethod	80052000	USD
	us-gaap	Noncontrolling Interest Increase From Sale Of Parent Equity Interest NoncontrollingInterestIncreaseFromSaleOfParentEquityInterest	0	USD
	us-gaap	Stock Issued During Period Value Share Based Compensation StockIssuedDuringPeriodValueShareBasedCompensation	-16000	USD
	us-gaap	Adjustments To Additional Paid In Capital Sharebased Compensation Requisite Service Period Recognition Value AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue	11588000	USD
	us-gaap	Common Stock Dividends Per Share Cash Paid CommonStockDividendsPerShareCashPaid	0.788
	us-gaap	Dividends Common Stock Cash DividendsCommonStockCash	92204000	USD
CY2021Q3	us-gaap	Stockholders Equity Including Portion Attributable To Noncontrolling Interest StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest	3491221000	USD
CY2019Q4	us-gaap	Stockholders Equity Including Portion Attributable To Noncontrolling Interest StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest	3138472000	USD
	us-gaap	Profit Loss ProfitLoss	221689000	USD
	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	232991000	USD
	us-gaap	Minority Interest Decrease From Distributions To Noncontrolling Interest Holders MinorityInterestDecreaseFromDistributionsToNoncontrollingInterestHolders	708000	USD
	us-gaap	Stock Redeemed Or Called During Period Value StockRedeemedOrCalledDuringPeriodValue	-150000000	USD
	us-gaap	Treasury Stock Value Acquired Cost Method TreasuryStockValueAcquiredCostMethod	53760000	USD
	us-gaap	Stock Issued During Period Value Share Based Compensation StockIssuedDuringPeriodValueShareBasedCompensation	-27000	USD
	us-gaap	Adjustments To Additional Paid In Capital Sharebased Compensation Requisite Service Period Recognition Value AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue	11231000	USD
	us-gaap	Common Stock Dividends Per Share Cash Paid CommonStockDividendsPerShareCashPaid	0.771
	us-gaap	Dividends Common Stock Cash DividendsCommonStockCash	90640000	USD
	us-gaap	Preferred Stock Dividends Per Share Cash Paid PreferredStockDividendsPerShareCashPaid	1.125
	us-gaap	Dividends Preferred Stock Cash DividendsPreferredStockCash	6750000	USD
CY2020Q3	us-gaap	Stockholders Equity Including Portion Attributable To Noncontrolling Interest StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest	3306264000	USD
	us-gaap	Profit Loss ProfitLoss	425232000	USD
	us-gaap	Profit Loss ProfitLoss	221689000	USD
	us-gaap	Provision For Loan And Lease Losses ProvisionForLoanAndLeaseLosses	-59272000	USD
	us-gaap	Provision For Loan And Lease Losses ProvisionForLoanAndLeaseLosses	141593000	USD
	us-gaap	Depreciation Amortization And Accretion Net DepreciationAmortizationAndAccretionNet	33554000	USD
	us-gaap	Depreciation Amortization And Accretion Net DepreciationAmortizationAndAccretionNet	32462000	USD
	us-gaap	Accretion Amortization Of Discounts And Premiums Investments AccretionAmortizationOfDiscountsAndPremiumsInvestments	-51822000	USD
	us-gaap	Accretion Amortization Of Discounts And Premiums Investments AccretionAmortizationOfDiscountsAndPremiumsInvestments	-37623000	USD
	us-gaap	Gain Loss On Investments GainLossOnInvestments	39765000	USD
	us-gaap	Gain Loss On Investments GainLossOnInvestments	-1275000	USD
	us-gaap	Gain Loss On Sale Of Loans And Leases GainLossOnSaleOfLoansAndLeases	18849000	USD
	us-gaap	Gain Loss On Sale Of Loans And Leases GainLossOnSaleOfLoansAndLeases	8267000	USD
	cbsh	Origination Of Loans Held For Sale OriginationOfLoansHeldForSale	442853000	USD
	cbsh	Origination Of Loans Held For Sale OriginationOfLoansHeldForSale	169774000	USD
	us-gaap	Proceeds From Sale Of Loans Held For Sale ProceedsFromSaleOfLoansHeldForSale	485231000	USD
	us-gaap	Proceeds From Sale Of Loans Held For Sale ProceedsFromSaleOfLoansHeldForSale	152825000	USD
	us-gaap	Increase Decrease In Trading Securities IncreaseDecreaseInTradingSecurities	9093000	USD
	us-gaap	Increase Decrease In Trading Securities IncreaseDecreaseInTradingSecurities	-5636000	USD
	us-gaap	Share Based Compensation ShareBasedCompensation	11588000	USD
	us-gaap	Share Based Compensation ShareBasedCompensation	11231000	USD
	us-gaap	Increase Decrease In Interest And Dividends Receivable IncreaseDecreaseInInterestAndDividendsReceivable	-11449000	USD
	us-gaap	Increase Decrease In Interest And Dividends Receivable IncreaseDecreaseInInterestAndDividendsReceivable	11012000	USD
	us-gaap	Increase Decrease In Interest Payable Net IncreaseDecreaseInInterestPayableNet	-3168000	USD
	us-gaap	Increase Decrease In Interest Payable Net IncreaseDecreaseInInterestPayableNet	-7670000	USD
	us-gaap	Increase Decrease In Accrued Income Taxes Payable IncreaseDecreaseInAccruedIncomeTaxesPayable	19831000	USD
	us-gaap	Increase Decrease In Accrued Income Taxes Payable IncreaseDecreaseInAccruedIncomeTaxesPayable	-7942000	USD
	cbsh	Proceeds From The Termination Of Interest Rate Floors ProceedsFromTheTerminationOfInterestRateFloors	0	USD
	cbsh	Proceeds From The Termination Of Interest Rate Floors ProceedsFromTheTerminationOfInterestRateFloors	110640000	USD
	us-gaap	Increase Decrease In Other Operating Capital Net IncreaseDecreaseInOtherOperatingCapitalNet	-20418000	USD
	us-gaap	Increase Decrease In Other Operating Capital Net IncreaseDecreaseInOtherOperatingCapitalNet	37926000	USD
	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	486125000	USD
	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	472383000	USD
	us-gaap	Proceeds From Equity Method Investment Dividends Or Distributions Return Of Capital ProceedsFromEquityMethodInvestmentDividendsOrDistributionsReturnOfCapital	13540000	USD
	us-gaap	Proceeds From Equity Method Investment Dividends Or Distributions Return Of Capital ProceedsFromEquityMethodInvestmentDividendsOrDistributionsReturnOfCapital	0	USD
	cbsh	Proceedsfromsalesandmaturitiesofavailableforsaledebtequityandothersecurities Proceedsfromsalesandmaturitiesofavailableforsaledebtequityandothersecurities	10060000	USD
	cbsh	Proceedsfromsalesandmaturitiesofavailableforsaledebtequityandothersecurities Proceedsfromsalesandmaturitiesofavailableforsaledebtequityandothersecurities	574376000	USD
	us-gaap	Proceeds From Maturities Prepayments And Calls Of Available For Sale Securities ProceedsFromMaturitiesPrepaymentsAndCallsOfAvailableForSaleSecurities	2571116000	USD
	us-gaap	Proceeds From Maturities Prepayments And Calls Of Available For Sale Securities ProceedsFromMaturitiesPrepaymentsAndCallsOfAvailableForSaleSecurities	1856780000	USD
	us-gaap	Payments To Acquire Investments PaymentsToAcquireInvestments	4457716000	USD
	us-gaap	Payments To Acquire Investments PaymentsToAcquireInvestments	5135211000	USD
	us-gaap	Payments For Proceeds From Loans And Leases PaymentsForProceedsFromLoansAndLeases	-1166769000	USD
	us-gaap	Payments For Proceeds From Loans And Leases PaymentsForProceedsFromLoansAndLeases	1710009000	USD
	us-gaap	Payments For Securities Purchased Under Agreements To Resell PaymentsForSecuritiesPurchasedUnderAgreementsToResell	900000000	USD
	us-gaap	Payments For Securities Purchased Under Agreements To Resell PaymentsForSecuritiesPurchasedUnderAgreementsToResell	0	USD
	us-gaap	Payments To Acquire Property Plant And Equipment PaymentsToAcquirePropertyPlantAndEquipment	37385000	USD
	us-gaap	Payments To Acquire Property Plant And Equipment PaymentsToAcquirePropertyPlantAndEquipment	29192000	USD
	us-gaap	Proceeds From Sale Of Property Plant And Equipment ProceedsFromSaleOfPropertyPlantAndEquipment	4786000	USD
	us-gaap	Proceeds From Sale Of Property Plant And Equipment ProceedsFromSaleOfPropertyPlantAndEquipment	313000	USD
	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-1628830000	USD
	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-4442943000	USD
	cbsh	Net Increase Decrease Non Interest Bearing Savings Interest Checking And Money Market Deposits NetIncreaseDecreaseNonInterestBearingSavingsInterestCheckingAndMoneyMarketDeposits	1428561000	USD
	cbsh	Net Increase Decrease Non Interest Bearing Savings Interest Checking And Money Market Deposits NetIncreaseDecreaseNonInterestBearingSavingsInterestCheckingAndMoneyMarketDeposits	5138314000	USD
	us-gaap	Increase Decrease In Time Deposits IncreaseDecreaseInTimeDeposits	-228916000	USD
	us-gaap	Increase Decrease In Time Deposits IncreaseDecreaseInTimeDeposits	-17565000	USD
	us-gaap	Increase Decrease In Federal Funds Purchased And Securities Sold Under Agreements To Repurchase Net IncreaseDecreaseInFederalFundsPurchasedAndSecuritiesSoldUnderAgreementsToRepurchaseNet	155370000	USD
	us-gaap	Increase Decrease In Federal Funds Purchased And Securities Sold Under Agreements To Repurchase Net IncreaseDecreaseInFederalFundsPurchasedAndSecuritiesSoldUnderAgreementsToRepurchaseNet	-197708000	USD
	cbsh	Net Increase Decrease In Short Term Borrowings NetIncreaseDecreaseInShortTermBorrowings	3204000	USD
	cbsh	Net Increase Decrease In Short Term Borrowings NetIncreaseDecreaseInShortTermBorrowings	-1636000	USD
	us-gaap	Payments For Repurchase Of Redeemable Preferred Stock PaymentsForRepurchaseOfRedeemablePreferredStock	0	USD
	us-gaap	Payments For Repurchase Of Redeemable Preferred Stock PaymentsForRepurchaseOfRedeemablePreferredStock	150000000	USD
	us-gaap	Payments For Repurchase Of Common Stock PaymentsForRepurchaseOfCommonStock	80052000	USD
	us-gaap	Payments For Repurchase Of Common Stock PaymentsForRepurchaseOfCommonStock	53760000	USD
	cbsh	Paymentsforstockvalueissuedundersharebasedcompensationplans Paymentsforstockvalueissuedundersharebasedcompensationplans	16000	USD
	cbsh	Paymentsforstockvalueissuedundersharebasedcompensationplans Paymentsforstockvalueissuedundersharebasedcompensationplans	27000	USD
	us-gaap	Payments Of Dividends Common Stock PaymentsOfDividendsCommonStock	92204000	USD
	us-gaap	Payments Of Dividends Common Stock PaymentsOfDividendsCommonStock	90640000	USD
	us-gaap	Payments Of Dividends Preferred Stock And Preference Stock PaymentsOfDividendsPreferredStockAndPreferenceStock	0	USD
	us-gaap	Payments Of Dividends Preferred Stock And Preference Stock PaymentsOfDividendsPreferredStockAndPreferenceStock	6750000	USD
	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	1185947000	USD
	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	4620228000	USD
	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Excluding Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseExcludingExchangeRateEffect	43242000	USD
	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Excluding Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseExcludingExchangeRateEffect	649668000	USD
CY2020Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	2208328000	USD
CY2019Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	907808000	USD
CY2021Q3	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	2251570000	USD
CY2020Q3	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	1557476000	USD
	us-gaap	Income Taxes Paid Net IncomeTaxesPaidNet	87989000	USD
	us-gaap	Income Taxes Paid Net IncomeTaxesPaidNet	58750000	USD
	us-gaap	Interest Paid Net InterestPaidNet	13213000	USD
	us-gaap	Interest Paid Net InterestPaidNet	45508000	USD
	us-gaap	Transfer To Other Real Estate TransferToOtherRealEstate	172000	USD
	us-gaap	Transfer To Other Real Estate TransferToOtherRealEstate	57000	USD
CY2021Q3	us-gaap	Restricted Cash And Cash Equivalents RestrictedCashAndCashEquivalents	18600000	USD
CY2020Q3	us-gaap	Restricted Cash And Cash Equivalents RestrictedCashAndCashEquivalents	25900000	USD
CY2021Q3	us-gaap	Loans And Leases Receivable Gross Carrying Amount LoansAndLeasesReceivableGrossCarryingAmount	15148390000	USD
CY2020Q4	us-gaap	Loans And Leases Receivable Gross Carrying Amount LoansAndLeasesReceivableGrossCarryingAmount	16329641000	USD
CY2021Q3	us-gaap	Interest Receivable InterestReceivable	33000000	USD
CY2020Q4	us-gaap	Interest Receivable InterestReceivable	41900000	USD
CY2021Q3	us-gaap	Pledged Financial Instruments Not Separately Reported Loans Receivable Pledged For Federal Home Loan Bank Debt PledgedFinancialInstrumentsNotSeparatelyReportedLoansReceivablePledgedForFederalHomeLoanBankDebt	3500000000	USD
CY2021Q3	us-gaap	Pledged Financial Instruments Not Separately Reported Loans Receivable Pledged As Collateral PledgedFinancialInstrumentsNotSeparatelyReportedLoansReceivablePledgedAsCollateral	1300000000	USD
CY2021Q2	us-gaap	Financing Receivable Allowance For Credit Losses FinancingReceivableAllowanceForCreditLosses	172395000	USD
CY2020Q4	us-gaap	Financing Receivable Allowance For Credit Losses FinancingReceivableAllowanceForCreditLosses	220834000	USD
CY2021Q3	us-gaap	Provision For Loan Losses Expensed ProvisionForLoanLossesExpensed	5961000	USD
	us-gaap	Provision For Loan Losses Expensed ProvisionForLoanLossesExpensed	43749000	USD
CY2021Q3	us-gaap	Financing Receivable Allowance For Credit Losses Write Offs FinancingReceivableAllowanceForCreditLossesWriteOffs	6577000	USD
	us-gaap	Financing Receivable Allowance For Credit Losses Write Offs FinancingReceivableAllowanceForCreditLossesWriteOffs	28386000	USD
CY2021Q3	us-gaap	Financing Receivable Allowance For Credit Losses Recovery FinancingReceivableAllowanceForCreditLossesRecovery	2918000	USD
	us-gaap	Financing Receivable Allowance For Credit Losses Recovery FinancingReceivableAllowanceForCreditLossesRecovery	14076000	USD
CY2021Q3	us-gaap	Financing Receivable Allowance For Credit Loss Writeoff After Recovery FinancingReceivableAllowanceForCreditLossWriteoffAfterRecovery	3659000	USD
	us-gaap	Financing Receivable Allowance For Credit Loss Writeoff After Recovery FinancingReceivableAllowanceForCreditLossWriteoffAfterRecovery	14310000	USD
CY2021Q3	us-gaap	Financing Receivable Allowance For Credit Losses FinancingReceivableAllowanceForCreditLosses	162775000	USD
CY2021Q3	us-gaap	Financing Receivable Allowance For Credit Losses FinancingReceivableAllowanceForCreditLosses	162775000	USD
CY2021Q2	us-gaap	Off Balance Sheet Credit Loss Liability OffBalanceSheetCreditLossLiability	24208000	USD
CY2020Q4	us-gaap	Off Balance Sheet Credit Loss Liability OffBalanceSheetCreditLossLiability	38307000	USD
CY2021Q3	us-gaap	Off Balance Sheet Credit Loss Liability Credit Loss Expense Reversal OffBalanceSheetCreditLossLiabilityCreditLossExpenseReversal	1424000	USD
	us-gaap	Off Balance Sheet Credit Loss Liability Credit Loss Expense Reversal OffBalanceSheetCreditLossLiabilityCreditLossExpenseReversal	15523000	USD
CY2021Q3	us-gaap	Off Balance Sheet Credit Loss Liability OffBalanceSheetCreditLossLiability	22784000	USD
CY2021Q3	us-gaap	Off Balance Sheet Credit Loss Liability OffBalanceSheetCreditLossLiability	22784000	USD
CY2021Q3	cbsh	Financing Receivable Allowance For Credit Loss And Unfunded Lending Commitments Total FinancingReceivableAllowanceForCreditLossAndUnfundedLendingCommitmentsTotal	185559000	USD
CY2021Q3	cbsh	Financing Receivable Allowance For Credit Loss And Unfunded Lending Commitments Total FinancingReceivableAllowanceForCreditLossAndUnfundedLendingCommitmentsTotal	185559000	USD
CY2020Q2	us-gaap	Financing Receivable Allowance For Credit Losses FinancingReceivableAllowanceForCreditLosses	240744000	USD
CY2019Q4	us-gaap	Financing Receivable Allowance For Credit Losses FinancingReceivableAllowanceForCreditLosses	139643000	USD
CY2020Q3	us-gaap	Provision For Loan Losses Expensed ProvisionForLoanLossesExpensed	-3200000	USD
	us-gaap	Provision For Loan Losses Expensed ProvisionForLoanLossesExpensed	-123559000	USD
CY2020Q3	us-gaap	Financing Receivable Allowance For Credit Losses Write Offs FinancingReceivableAllowanceForCreditLossesWriteOffs	10649000	USD
	us-gaap	Financing Receivable Allowance For Credit Losses Write Offs FinancingReceivableAllowanceForCreditLossesWriteOffs	36286000	USD
CY2020Q3	us-gaap	Financing Receivable Allowance For Credit Losses Recovery FinancingReceivableAllowanceForCreditLossesRecovery	3065000	USD
	us-gaap	Financing Receivable Allowance For Credit Losses Recovery FinancingReceivableAllowanceForCreditLossesRecovery	9444000	USD
CY2020Q3	us-gaap	Financing Receivable Allowance For Credit Loss Writeoff After Recovery FinancingReceivableAllowanceForCreditLossWriteoffAfterRecovery	7584000	USD
	us-gaap	Financing Receivable Allowance For Credit Loss Writeoff After Recovery FinancingReceivableAllowanceForCreditLossWriteoffAfterRecovery	26842000	USD
CY2020Q3	us-gaap	Financing Receivable Allowance For Credit Losses FinancingReceivableAllowanceForCreditLosses	236360000	USD
CY2020Q3	us-gaap	Financing Receivable Allowance For Credit Losses FinancingReceivableAllowanceForCreditLosses	236360000	USD
CY2020Q2	us-gaap	Off Balance Sheet Credit Loss Liability OffBalanceSheetCreditLossLiability	35299000	USD
CY2019Q4	us-gaap	Off Balance Sheet Credit Loss Liability OffBalanceSheetCreditLossLiability	17165000	USD
CY2020Q3	us-gaap	Off Balance Sheet Credit Loss Liability Credit Loss Expense Reversal OffBalanceSheetCreditLossLiabilityCreditLossExpenseReversal	99000	USD
	us-gaap	Off Balance Sheet Credit Loss Liability Credit Loss Expense Reversal OffBalanceSheetCreditLossLiabilityCreditLossExpenseReversal	-18035000	USD
CY2020Q3	us-gaap	Off Balance Sheet Credit Loss Liability OffBalanceSheetCreditLossLiability	35200000	USD
CY2020Q3	us-gaap	Off Balance Sheet Credit Loss Liability OffBalanceSheetCreditLossLiability	35200000	USD
CY2020Q3	cbsh	Financing Receivable Allowance For Credit Loss And Unfunded Lending Commitments Total FinancingReceivableAllowanceForCreditLossAndUnfundedLendingCommitmentsTotal	271560000	USD
CY2020Q3	cbsh	Financing Receivable Allowance For Credit Loss And Unfunded Lending Commitments Total FinancingReceivableAllowanceForCreditLossAndUnfundedLendingCommitmentsTotal	271560000	USD
CY2021Q3	cbsh	Financing Receivable Recorded Investment Currentor Lessthan30days Past Due FinancingReceivableRecordedInvestmentCurrentorLessthan30daysPastDue	15094887000	USD
CY2021Q3	cbsh	Financing Receivable Recorded Investment Thirty To Eighty Nine Days Past Due FinancingReceivableRecordedInvestmentThirtyToEightyNineDaysPastDue	32586000	USD
CY2021Q3	us-gaap	Financing Receivable Recorded Investment90 Days Past Due And Still Accruing FinancingReceivableRecordedInvestment90DaysPastDueAndStillAccruing	10496000	USD
CY2021Q3	us-gaap	Financing Receivable Recorded Investment Nonaccrual Status FinancingReceivableRecordedInvestmentNonaccrualStatus	10421000	USD
CY2021Q3	us-gaap	Loans And Leases Receivable Gross Carrying Amount LoansAndLeasesReceivableGrossCarryingAmount	15148390000	USD
CY2020Q4	cbsh	Financing Receivable Recorded Investment Currentor Lessthan30days Past Due FinancingReceivableRecordedInvestmentCurrentorLessthan30daysPastDue	16230056000	USD
CY2020Q4	cbsh	Financing Receivable Recorded Investment Thirty To Eighty Nine Days Past Due FinancingReceivableRecordedInvestmentThirtyToEightyNineDaysPastDue	50855000	USD
CY2020Q4	us-gaap	Financing Receivable Recorded Investment90 Days Past Due And Still Accruing FinancingReceivableRecordedInvestment90DaysPastDueAndStillAccruing	22190000	USD
CY2020Q4	us-gaap	Financing Receivable Recorded Investment Nonaccrual Status FinancingReceivableRecordedInvestmentNonaccrualStatus	26540000	USD
CY2020Q4	us-gaap	Loans And Leases Receivable Gross Carrying Amount LoansAndLeasesReceivableGrossCarryingAmount	16329641000	USD
CY2021Q3	cbsh	Credit Quality Personal Real Estate Loans Excluded CreditQualityPersonalRealEstateLoansExcluded	186000000	USD
CY2020Q4	cbsh	Credit Quality Personal Real Estate Loans Excluded CreditQualityPersonalRealEstateLoansExcluded	191100000	USD
CY2021Q3	cbsh	Consumer Healthcare Loans Excluded ConsumerHealthcareLoansExcluded	189600000	USD
CY2020Q4	cbsh	Consumer Healthcare Loans Excluded ConsumerHealthcareLoansExcluded	188100000	USD
CY2021Q3	cbsh	Credit Quality Personal Banking Loan Table Percentage Loans Excluded CreditQualityPersonalBankingLoanTablePercentageLoansExcluded	0.07	Rate
CY2021Q3	us-gaap	Financing Receivable Modifications Recorded Investment FinancingReceivableModificationsRecordedInvestment	129858000	USD
CY2020Q4	us-gaap	Financing Receivable Modifications Recorded Investment FinancingReceivableModificationsRecordedInvestment	140627000	USD
CY2020Q4	us-gaap	Other Foreclosed Assets OtherForeclosedAssets	1400000	USD
	cbsh	Period After Which Loans Are Deemed In Default PeriodAfterWhichLoansAreDeemedInDefault	P90D
CY2021Q3	us-gaap	Financing Receivable Modifications Recorded Investment FinancingReceivableModificationsRecordedInvestment	129858000	USD
CY2021Q3	cbsh	Financing Receivable Troubled Debt Restructurings That Subsequently Defaulted Recorded Investment FinancingReceivableTroubledDebtRestructuringsThatSubsequentlyDefaultedRecordedInvestment	1573000	USD
	cbsh	Effect On Interest Income Resulting From Modification To Credit Card Loans EffectOnInterestIncomeResultingFromModificationToCreditCardLoans	815000	USD
CY2021Q3	us-gaap	Loans And Leases Receivable Impaired Commitment To Lend LoansAndLeasesReceivableImpairedCommitmentToLend	245000	USD
CY2021Q3	cbsh	Letters Of Credit To Customers With Substandard Risk Rating LettersOfCreditToCustomersWithSubstandardRiskRating	24000000	USD
CY2021Q3	us-gaap	Mortgages Held For Sale Fair Value Disclosure MortgagesHeldForSaleFairValueDisclosure	12000000	USD
CY2021Q3	cbsh	Unpaid Principal Balanceon Personal Real Estate Loans Heldfor Sale UnpaidPrincipalBalanceonPersonalRealEstateLoansHeldforSale	11600000	USD
CY2021Q3	cbsh	Student Loans Heldfor Sale Lowerof Costor Fair Value StudentLoansHeldforSaleLowerofCostorFairValue	4100000	USD
CY2021Q3	cbsh	Hfs Loansonnonaccrualstatus HFSLoansonnonaccrualstatus	0	USD
CY2021Q3	cbsh	Loans Held For Sale90 Days Past Dueand Still Accruing LoansHeldForSale90DaysPastDueandStillAccruing	0	USD
CY2021Q3	us-gaap	Real Estate Acquired Through Foreclosure RealEstateAcquiredThroughForeclosure	115000	USD
CY2020Q4	us-gaap	Real Estate Acquired Through Foreclosure RealEstateAcquiredThroughForeclosure	93000	USD
CY2021Q3	us-gaap	Other Foreclosed Assets OtherForeclosedAssets	1000000	USD
CY2021Q3	us-gaap	Available For Sale Securities Debt Securities AvailableForSaleSecuritiesDebtSecurities	14165656000	USD
CY2020Q4	us-gaap	Available For Sale Securities Debt Securities AvailableForSaleSecuritiesDebtSecurities	12449264000	USD
CY2021Q3	us-gaap	Trading Securities TradingSecurities	40114000	USD
CY2020Q4	us-gaap	Trading Securities TradingSecurities	35321000	USD
CY2021Q3	us-gaap	Equity Securities Fv Ni EquitySecuritiesFvNi	7118000	USD
CY2020Q4	us-gaap	Equity Securities Fv Ni EquitySecuritiesFvNi	2966000	USD
CY2021Q3	cbsh	Equtiy Securitieswithout Readily Determinable Fair Values EqutiySecuritieswithoutReadilyDeterminableFairValues	2056000	USD
CY2020Q4	cbsh	Equtiy Securitieswithout Readily Determinable Fair Values EqutiySecuritieswithoutReadilyDeterminableFairValues	1397000	USD
CY2021Q3	us-gaap	Federal Reserve Bank Stock FederalReserveBankStock	34379000	USD
CY2020Q4	us-gaap	Federal Reserve Bank Stock FederalReserveBankStock	34070000	USD
CY2021Q3	us-gaap	Federal Home Loan Bank Stock FederalHomeLoanBankStock	10185000	USD
CY2020Q4	us-gaap	Federal Home Loan Bank Stock FederalHomeLoanBankStock	10307000	USD
CY2021Q3	us-gaap	Equity Method Investments EquityMethodInvestments	1834000	USD
CY2020Q4	us-gaap	Equity Method Investments EquityMethodInvestments	18000000	USD
CY2021Q3	cbsh	Private Equity Investments PrivateEquityInvestments	138052000	USD
CY2020Q4	cbsh	Private Equity Investments PrivateEquityInvestments	94368000	USD
CY2021Q3	cbsh	Total Investment Securities TotalInvestmentSecurities	14399394000	USD
CY2020Q4	cbsh	Total Investment Securities TotalInvestmentSecurities	12645693000	USD
CY2021Q3	us-gaap	Interest Receivable Current InterestReceivableCurrent	39400000	USD
CY2020Q4	us-gaap	Interest Receivable Current InterestReceivableCurrent	41500000	USD
CY2021Q3	us-gaap	Available For Sale Debt Securities Amortized Cost Basis AvailableForSaleDebtSecuritiesAmortizedCostBasis	14027284000	USD
CY2021Q3	us-gaap	Available For Sale Securities Debt Securities AvailableForSaleSecuritiesDebtSecurities	14165656000	USD
	cbsh	Percentage Decrease In Fair Value Below Amortized Cost PercentageDecreaseInFairValueBelowAmortizedCost	0.20
CY2021Q3	cbsh	Fair Value Securities On Impairment Watch List FairValueSecuritiesOnImpairmentWatchList	13700000	USD
CY2020Q4	cbsh	Fair Value Securities On Impairment Watch List FairValueSecuritiesOnImpairmentWatchList	31000000	USD
CY2021Q3	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position Less Than12 Months DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12Months	6022640000	USD
CY2021Q3	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position Less Than12 Months Accumulated Loss DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss	67608000	USD
CY2021Q3	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position12 Months Or Longer DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLonger	184279000	USD
CY2021Q3	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position12 Months Or Longer Accumulated Loss DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLongerAccumulatedLoss	4435000	USD
CY2021Q3	us-gaap	Debt Securities Available For Sale Unrealized Loss Position DebtSecuritiesAvailableForSaleUnrealizedLossPosition	6206919000	USD
CY2021Q3	us-gaap	Debt Securities Available For Sale Unrealized Loss Position Accumulated Loss DebtSecuritiesAvailableForSaleUnrealizedLossPositionAccumulatedLoss	72043000	USD
CY2020Q4	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position Less Than12 Months DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12Months	694458000	USD
CY2020Q4	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position Less Than12 Months Accumulated Loss DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss	3741000	USD
CY2020Q4	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position12 Months Or Longer DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLonger	253734000	USD
CY2020Q4	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position12 Months Or Longer Accumulated Loss DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLongerAccumulatedLoss	2617000	USD
CY2020Q4	us-gaap	Debt Securities Available For Sale Unrealized Loss Position DebtSecuritiesAvailableForSaleUnrealizedLossPosition	948192000	USD
CY2020Q4	us-gaap	Debt Securities Available For Sale Unrealized Loss Position Accumulated Loss DebtSecuritiesAvailableForSaleUnrealizedLossPositionAccumulatedLoss	6358000	USD
CY2021Q3	us-gaap	Debt Securities Available For Sale Unrealized Loss Position DebtSecuritiesAvailableForSaleUnrealizedLossPosition	6200000000	USD
CY2020Q4	us-gaap	Debt Securities Available For Sale Unrealized Loss Position DebtSecuritiesAvailableForSaleUnrealizedLossPosition	948200000	USD
CY2021Q3	us-gaap	Debt Securities Available For Sale Unrealized Loss Position Accumulated Loss DebtSecuritiesAvailableForSaleUnrealizedLossPositionAccumulatedLoss	72000000	USD
	cbsh	Af Ssecuritiesinlosspositionatperiodendchangeinunrealizedloss AFSsecuritiesinlosspositionatperiodendchangeinunrealizedloss	65700000	USD
CY2021Q3	us-gaap	Available For Sale Debt Securities Amortized Cost Basis AvailableForSaleDebtSecuritiesAmortizedCostBasis	14027284000	USD
CY2021Q3	cbsh	Available For Sale Securities Gross Unreailzed Gainat Period End AvailableForSaleSecuritiesGrossUnreailzedGainatPeriodEnd	210415000	USD
CY2021Q3	cbsh	Available For Sale Securities Gross Unrealized Lossat Period End AvailableForSaleSecuritiesGrossUnrealizedLossatPeriodEnd	72043000	USD
CY2021Q3	us-gaap	Debt Securities Available For Sale Allowance For Credit Loss DebtSecuritiesAvailableForSaleAllowanceForCreditLoss	0	USD
CY2021Q3	us-gaap	Available For Sale Securities Debt Securities AvailableForSaleSecuritiesDebtSecurities	14165656000	USD
CY2020Q4	us-gaap	Available For Sale Debt Securities Amortized Cost Basis AvailableForSaleDebtSecuritiesAmortizedCostBasis	12097533000	USD
CY2020Q4	cbsh	Available For Sale Securities Gross Unreailzed Gainat Period End AvailableForSaleSecuritiesGrossUnreailzedGainatPeriodEnd	358089000	USD
CY2020Q4	cbsh	Available For Sale Securities Gross Unrealized Lossat Period End AvailableForSaleSecuritiesGrossUnrealizedLossatPeriodEnd	6358000	USD
CY2020Q4	us-gaap	Debt Securities Available For Sale Allowance For Credit Loss DebtSecuritiesAvailableForSaleAllowanceForCreditLoss	0	USD
CY2020Q4	us-gaap	Available For Sale Securities Debt Securities AvailableForSaleSecuritiesDebtSecurities	12449264000	USD
	us-gaap	Proceeds From Sale Of Available For Sale Securities Debt ProceedsFromSaleOfAvailableForSaleSecuritiesDebt	0	USD
	us-gaap	Proceeds From Sale Of Available For Sale Securities Debt ProceedsFromSaleOfAvailableForSaleSecuritiesDebt	574374000	USD
	us-gaap	Proceeds From Sale Of Equity Securities Fv Ni ProceedsFromSaleOfEquitySecuritiesFvNi	0	USD
	us-gaap	Proceeds From Sale Of Equity Securities Fv Ni ProceedsFromSaleOfEquitySecuritiesFvNi	2000	USD
	cbsh	Proceeds From Sale Of Other Securities ProceedsFromSaleOfOtherSecurities	10060000	USD
	cbsh	Proceeds From Sale Of Other Securities ProceedsFromSaleOfOtherSecurities	0	USD
	cbsh	Proceedsfromsalesandmaturitiesofavailableforsaledebtequityandothersecurities Proceedsfromsalesandmaturitiesofavailableforsaledebtequityandothersecurities	10060000	USD
	cbsh	Proceedsfromsalesandmaturitiesofavailableforsaledebtequityandothersecurities Proceedsfromsalesandmaturitiesofavailableforsaledebtequityandothersecurities	574376000	USD
	us-gaap	Gain Loss On Investments GainLossOnInvestments	39765000	USD
	us-gaap	Gain Loss On Investments GainLossOnInvestments	-1275000	USD
CY2021Q3	cbsh	Investment Securities Pledged At Fair Value InvestmentSecuritiesPledgedAtFairValue	5700000000	USD
CY2020Q4	cbsh	Investment Securities Pledged At Fair Value InvestmentSecuritiesPledgedAtFairValue	4800000000	USD
CY2021Q3	us-gaap	Financial Instruments Owned And Pledged As Collateral Amount Eligible To Be Repledged By Counterparty FinancialInstrumentsOwnedAndPledgedAsCollateralAmountEligibleToBeRepledgedByCounterparty	213100000	USD
CY2021Q3	cbsh	Investments Exceeding Ten Percent Of Stockholders Equity InvestmentsExceedingTenPercentOfStockholdersEquity	0
CY2021Q3	cbsh	Percentage Of Stockholders Equity Of Which No Investment From Single Issuer Exceeds PercentageOfStockholdersEquityOfWhichNoInvestmentFromSingleIssuerExceeds	0.10
CY2021Q3	us-gaap	Finite Lived Intangible Assets Gross FiniteLivedIntangibleAssetsGross	51017000	USD
CY2021Q3	us-gaap	Finite Lived Intangible Assets Accumulated Amortization FiniteLivedIntangibleAssetsAccumulatedAmortization	39176000	USD
CY2021Q3	us-gaap	Valuation Allowances And Reserves Balance ValuationAllowancesAndReservesBalance	983000	USD
CY2021Q3	us-gaap	Finite Lived Intangible Assets Net FiniteLivedIntangibleAssetsNet	10858000	USD
CY2020Q4	us-gaap	Finite Lived Intangible Assets Gross FiniteLivedIntangibleAssetsGross	46508000	USD
CY2020Q4	us-gaap	Finite Lived Intangible Assets Accumulated Amortization FiniteLivedIntangibleAssetsAccumulatedAmortization	36798000	USD
CY2020Q4	us-gaap	Valuation Allowances And Reserves Balance ValuationAllowancesAndReservesBalance	2103000	USD
CY2021Q3	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	682000	USD
CY2020Q4	us-gaap	Finite Lived Intangible Assets Net FiniteLivedIntangibleAssetsNet	7607000	USD
CY2020Q3	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	859000	USD
	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	2400000	USD
	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	1600000	USD
CY2021Q3	us-gaap	Finite Lived Intangible Assets Amortization Expense Next Twelve Months FiniteLivedIntangibleAssetsAmortizationExpenseNextTwelveMonths	2929000	USD
CY2021Q3	us-gaap	Finite Lived Intangible Assets Amortization Expense Year Two FiniteLivedIntangibleAssetsAmortizationExpenseYearTwo	1799000	USD
CY2021Q3	us-gaap	Finite Lived Intangible Assets Amortization Expense Year Three FiniteLivedIntangibleAssetsAmortizationExpenseYearThree	1498000	USD
CY2021Q3	us-gaap	Finite Lived Intangible Assets Amortization Expense Year Four FiniteLivedIntangibleAssetsAmortizationExpenseYearFour	1244000	USD
CY2021Q3	us-gaap	Finite Lived Intangible Assets Amortization Expense Year Five FiniteLivedIntangibleAssetsAmortizationExpenseYearFive	1027000	USD
CY2021Q3	us-gaap	Goodwill Goodwill	138921000	USD
CY2020Q4	us-gaap	Goodwill Goodwill	138921000	USD
CY2021Q3	us-gaap	Sales Type And Direct Financing Leases Profit Loss SalesTypeAndDirectFinancingLeasesProfitLoss	5482000	USD
CY2020Q3	us-gaap	Sales Type And Direct Financing Leases Profit Loss SalesTypeAndDirectFinancingLeasesProfitLoss	6437000	USD
	us-gaap	Sales Type And Direct Financing Leases Profit Loss SalesTypeAndDirectFinancingLeasesProfitLoss	17398000	USD
	us-gaap	Sales Type And Direct Financing Leases Profit Loss SalesTypeAndDirectFinancingLeasesProfitLoss	19099000	USD
CY2021Q3	us-gaap	Operating Lease Lease Income OperatingLeaseLeaseIncome	1717000	USD
CY2020Q3	us-gaap	Operating Lease Lease Income OperatingLeaseLeaseIncome	2270000	USD
	us-gaap	Operating Lease Lease Income OperatingLeaseLeaseIncome	5721000	USD
	us-gaap	Operating Lease Lease Income OperatingLeaseLeaseIncome	6491000	USD
CY2021Q3	us-gaap	Lease Income LeaseIncome	7199000	USD
CY2020Q3	us-gaap	Lease Income LeaseIncome	8707000	USD
	us-gaap	Lease Income LeaseIncome	23119000	USD
	us-gaap	Lease Income LeaseIncome	25590000	USD
CY2021Q3	us-gaap	Defined Benefit Plan Service Cost DefinedBenefitPlanServiceCost	95000	USD
CY2020Q3	us-gaap	Defined Benefit Plan Service Cost DefinedBenefitPlanServiceCost	93000	USD
	us-gaap	Defined Benefit Plan Service Cost DefinedBenefitPlanServiceCost	284000	USD
	us-gaap	Defined Benefit Plan Service Cost DefinedBenefitPlanServiceCost	295000	USD
CY2021Q3	us-gaap	Defined Benefit Plan Interest Cost DefinedBenefitPlanInterestCost	514000	USD
CY2020Q3	us-gaap	Defined Benefit Plan Interest Cost DefinedBenefitPlanInterestCost	818000	USD
	us-gaap	Defined Benefit Plan Interest Cost DefinedBenefitPlanInterestCost	1626000	USD
	us-gaap	Defined Benefit Plan Contributions By Employer DefinedBenefitPlanContributionsByEmployer	0	USD
	us-gaap	Defined Benefit Plan Interest Cost DefinedBenefitPlanInterestCost	2463000	USD
CY2021Q3	us-gaap	Defined Benefit Plan Expected Return On Plan Assets DefinedBenefitPlanExpectedReturnOnPlanAssets	1151000	USD
CY2020Q3	us-gaap	Defined Benefit Plan Expected Return On Plan Assets DefinedBenefitPlanExpectedReturnOnPlanAssets	1317000	USD
	us-gaap	Defined Benefit Plan Expected Return On Plan Assets DefinedBenefitPlanExpectedReturnOnPlanAssets	3399000	USD
	us-gaap	Defined Benefit Plan Expected Return On Plan Assets DefinedBenefitPlanExpectedReturnOnPlanAssets	3911000	USD
CY2021Q3	us-gaap	Defined Benefit Plan Amortization Of Prior Service Cost Credit DefinedBenefitPlanAmortizationOfPriorServiceCostCredit	-67000	USD
CY2020Q3	us-gaap	Defined Benefit Plan Amortization Of Prior Service Cost Credit DefinedBenefitPlanAmortizationOfPriorServiceCostCredit	-67000	USD
	us-gaap	Defined Benefit Plan Amortization Of Prior Service Cost Credit DefinedBenefitPlanAmortizationOfPriorServiceCostCredit	-203000	USD
	us-gaap	Defined Benefit Plan Amortization Of Prior Service Cost Credit DefinedBenefitPlanAmortizationOfPriorServiceCostCredit	-203000	USD
CY2021Q3	us-gaap	Defined Benefit Plan Amortization Of Gains Losses DefinedBenefitPlanAmortizationOfGainsLosses	-669000	USD
CY2020Q3	us-gaap	Defined Benefit Plan Amortization Of Gains Losses DefinedBenefitPlanAmortizationOfGainsLosses	-503000	USD
	us-gaap	Defined Benefit Plan Amortization Of Gains Losses DefinedBenefitPlanAmortizationOfGainsLosses	-1971000	USD
	us-gaap	Defined Benefit Plan Amortization Of Gains Losses DefinedBenefitPlanAmortizationOfGainsLosses	-1587000	USD
CY2021Q3	us-gaap	Defined Benefit Plan Net Periodic Benefit Cost DefinedBenefitPlanNetPeriodicBenefitCost	60000	USD
CY2020Q3	us-gaap	Defined Benefit Plan Net Periodic Benefit Cost DefinedBenefitPlanNetPeriodicBenefitCost	30000	USD
	us-gaap	Defined Benefit Plan Net Periodic Benefit Cost DefinedBenefitPlanNetPeriodicBenefitCost	279000	USD
	us-gaap	Defined Benefit Plan Net Periodic Benefit Cost DefinedBenefitPlanNetPeriodicBenefitCost	231000	USD
CY2021Q3	us-gaap	Antidilutive Securities Excluded From Computation Of Earnings Per Share Amount AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount	94000	shares
CY2020Q3	us-gaap	Antidilutive Securities Excluded From Computation Of Earnings Per Share Amount AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount	413000	shares
	us-gaap	Antidilutive Securities Excluded From Computation Of Earnings Per Share Amount AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount	58000	shares
	us-gaap	Antidilutive Securities Excluded From Computation Of Earnings Per Share Amount AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount	295000	shares
CY2020Q3	us-gaap	Preferred Stock Dividend Rate Percentage PreferredStockDividendRatePercentage	0.0600
CY2020Q3	us-gaap	Preferred Stock Par Or Stated Value Per Share PreferredStockParOrStatedValuePerShare	1.00
CY2020Q4	us-gaap	Accumulated Other Comprehensive Income Loss Net Of Tax AccumulatedOtherComprehensiveIncomeLossNetOfTax	331377000	USD
	us-gaap	Other Comprehensive Income Loss Before Reclassifications Before Tax OtherComprehensiveIncomeLossBeforeReclassificationsBeforeTax	-213362000	USD
	us-gaap	Reclassification From Accumulated Other Comprehensive Income Current Period Before Tax ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodBeforeTax	16256000	USD
	us-gaap	Other Comprehensive Income Loss Before Tax OtherComprehensiveIncomeLossBeforeTax	-229618000	USD
	us-gaap	Other Comprehensive Income Loss Tax OtherComprehensiveIncomeLossTax	-57407000	USD
	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	-172211000	USD
CY2021Q3	us-gaap	Accumulated Other Comprehensive Income Loss Net Of Tax AccumulatedOtherComprehensiveIncomeLossNetOfTax	159166000	USD
CY2019Q4	us-gaap	Accumulated Other Comprehensive Income Loss Net Of Tax AccumulatedOtherComprehensiveIncomeLossNetOfTax	110444000	USD
	us-gaap	Other Comprehensive Income Loss Before Reclassifications Before Tax OtherComprehensiveIncomeLossBeforeReclassificationsBeforeTax	332285000	USD
	us-gaap	Reclassification From Accumulated Other Comprehensive Income Current Period Before Tax ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodBeforeTax	21631000	USD
	us-gaap	Other Comprehensive Income Loss Before Tax OtherComprehensiveIncomeLossBeforeTax	310654000	USD
	us-gaap	Other Comprehensive Income Loss Tax OtherComprehensiveIncomeLossTax	77663000	USD
	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	232991000	USD
CY2020Q3	us-gaap	Accumulated Other Comprehensive Income Loss Net Of Tax AccumulatedOtherComprehensiveIncomeLossNetOfTax	343435000	USD
	us-gaap	Number Of Operating Segments NumberOfOperatingSegments	3	Operating_Segments
CY2021Q3	us-gaap	Number Of Operating Segments NumberOfOperatingSegments	3	Operating_Segments
CY2021Q3	cbsh	Number Of Locations NumberOfLocations	155	Locations
CY2020Q3	us-gaap	Revenues Revenues	0	USD
	us-gaap	Revenues Revenues	0	USD
	us-gaap	Revenues Revenues	0	USD
CY2021Q3	us-gaap	Revenues Revenues	0	USD
CY2021Q3	us-gaap	Interest Income Expense Net InterestIncomeExpenseNet	214037000	USD
CY2021Q3	us-gaap	Provision For Loan And Lease Losses ProvisionForLoanAndLeaseLosses	-7385000	USD
CY2021Q3	us-gaap	Noninterest Income NoninterestIncome	137506000	USD
CY2021Q3	us-gaap	Gain Loss On Investments GainLossOnInvestments	13108000	USD
CY2021Q3	us-gaap	Noninterest Expense NoninterestExpense	211620000	USD
CY2021Q3	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	160416000	USD
	us-gaap	Interest Income Expense Net InterestIncomeExpenseNet	627767000	USD
	us-gaap	Provision For Loan And Lease Losses ProvisionForLoanAndLeaseLosses	-59272000	USD
	us-gaap	Noninterest Income NoninterestIncome	412694000	USD
	us-gaap	Gain Loss On Investments GainLossOnInvestments	39765000	USD
	us-gaap	Noninterest Expense NoninterestExpense	602319000	USD
	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	537179000	USD
CY2020Q3	us-gaap	Interest Income Expense Net InterestIncomeExpenseNet	215962000	USD
CY2020Q3	us-gaap	Provision For Loan And Lease Losses ProvisionForLoanAndLeaseLosses	3101000	USD
CY2020Q3	us-gaap	Noninterest Income NoninterestIncome	129572000	USD
CY2020Q3	us-gaap	Gain Loss On Investments GainLossOnInvestments	16155000	USD
CY2020Q3	us-gaap	Noninterest Expense NoninterestExpense	190858000	USD
CY2020Q3	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	167730000	USD
	us-gaap	Interest Income Expense Net InterestIncomeExpenseNet	620084000	USD
	us-gaap	Provision For Loan And Lease Losses ProvisionForLoanAndLeaseLosses	141593000	USD
	us-gaap	Noninterest Income NoninterestIncome	370750000	USD
	us-gaap	Gain Loss On Investments GainLossOnInvestments	-1275000	USD
	us-gaap	Noninterest Expense NoninterestExpense	572068000	USD
	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	275898000	USD
CY2021Q3	us-gaap	Derivative Notional Amount DerivativeNotionalAmount	2890598000	USD
CY2020Q4	us-gaap	Derivative Notional Amount DerivativeNotionalAmount	3015189000	USD
CY2021Q3	us-gaap	Derivative Assets DerivativeAssets	55065000	USD
CY2020Q4	us-gaap	Derivative Assets DerivativeAssets	89889000	USD
CY2021Q3	us-gaap	Derivative Liabilities DerivativeLiabilities	12466000	USD
CY2020Q4	us-gaap	Derivative Liabilities DerivativeLiabilities	18675000	USD
CY2021Q3	us-gaap	Derivative Asset Fair Value Gross Asset Including Not Subject To Master Netting Arrangement DerivativeAssetFairValueGrossAssetIncludingNotSubjectToMasterNettingArrangement	55065000	USD
CY2021Q3	cbsh	Derivative Asset Amount Offset By Liabiilty DerivativeAssetAmountOffsetByLiabiilty	0	USD
CY2021Q3	us-gaap	Derivative Assets DerivativeAssets	55065000	USD
CY2021Q3	us-gaap	Derivative Liability Fair Value Gross Liability Including Not Subject To Master Netting Arrangement DerivativeLiabilityFairValueGrossLiabilityIncludingNotSubjectToMasterNettingArrangement	12466000	USD
CY2021Q3	cbsh	Derivative Liability Amount Offset By Asset DerivativeLiabilityAmountOffsetByAsset	0	USD
CY2021Q3	us-gaap	Derivative Liabilities DerivativeLiabilities	12466000	USD
CY2020Q4	us-gaap	Derivative Asset Fair Value Gross Asset Including Not Subject To Master Netting Arrangement DerivativeAssetFairValueGrossAssetIncludingNotSubjectToMasterNettingArrangement	89889000	USD
CY2020Q4	cbsh	Derivative Asset Amount Offset By Liabiilty DerivativeAssetAmountOffsetByLiabiilty	0	USD
CY2020Q4	us-gaap	Derivative Assets DerivativeAssets	89889000	USD
CY2020Q4	us-gaap	Derivative Liability Fair Value Gross Liability Including Not Subject To Master Netting Arrangement DerivativeLiabilityFairValueGrossLiabilityIncludingNotSubjectToMasterNettingArrangement	18675000	USD
CY2020Q4	cbsh	Derivative Liability Amount Offset By Asset DerivativeLiabilityAmountOffsetByAsset	0	USD
CY2020Q4	us-gaap	Derivative Liabilities DerivativeLiabilities	18675000	USD
CY2021Q3	us-gaap	Allocated Share Based Compensation Expense AllocatedShareBasedCompensationExpense	3900000	USD
CY2020Q3	us-gaap	Allocated Share Based Compensation Expense AllocatedShareBasedCompensationExpense	3800000	USD
	us-gaap	Allocated Share Based Compensation Expense AllocatedShareBasedCompensationExpense	11600000	USD
	us-gaap	Allocated Share Based Compensation Expense AllocatedShareBasedCompensationExpense	11200000	USD
CY2020Q4	cbsh	Nonvested Share Awards Balances NonvestedShareAwardsBalances	1099866	shares
CY2020Q4	cbsh	Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Nonvested Share Awards Weighted Average Grant Date Unit Fair Value ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsNonvestedShareAwardsWeightedAverageGrantDateUnitFairValue	52.11
	cbsh	Nonvested Share Awards Granted In Period NonvestedShareAwardsGrantedInPeriod	224336	shares
	cbsh	Share Based Compensation Granted Nonvested Share Award Weighted Average Grant Date Fair Value ShareBasedCompensationGrantedNonvestedShareAwardWeightedAverageGrantDateFairValue	71.90
	cbsh	Nonvested Share Awards Vested In Period NonvestedShareAwardsVestedInPeriod	242139	shares
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	cbsh	Nonvested Share Awards Forfeited In Period NonvestedShareAwardsForfeitedInPeriod	20297	shares
	cbsh	Share Based Compensation Forfeited Nonvested Share Award Weighted Average Grant Date Fair Value ShareBasedCompensationForfeitedNonvestedShareAwardWeightedAverageGrantDateFairValue	58.68
CY2021Q3	cbsh	Nonvested Share Awards Balances NonvestedShareAwardsBalances	1061766	shares
CY2021Q3	cbsh	Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Nonvested Share Awards Weighted Average Grant Date Unit Fair Value ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsNonvestedShareAwardsWeightedAverageGrantDateUnitFairValue	58.14
	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Grants In Period Weighted Average Grant Date Fair Value ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriodWeightedAverageGrantDateFairValue	16.78
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	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Fair Value Assumptions Risk Free Interest Rate ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsRiskFreeInterestRate	0.007
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CY2020Q4	cbsh	Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Weighted Average Exercise Price ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsWeightedAverageExercisePrice	44.95
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	cbsh	Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Exercised In Period ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsExercisedInPeriod	214651	shares
	cbsh	Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Exercised In Period Weighted Average Exercise Price ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsExercisedInPeriodWeightedAverageExercisePrice	39.59
CY2021Q3	cbsh	Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Number ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNumber	857018	shares
CY2021Q3	cbsh	Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Weighted Average Exercise Price ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsWeightedAverageExercisePrice	48.55
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CY2021Q3	us-gaap	Sharebased Compensation Arrangement By Sharebased Payment Award Equity Instruments Other Than Options Aggregate Intrinsic Value Outstanding SharebasedCompensationArrangementBySharebasedPaymentAwardEquityInstrumentsOtherThanOptionsAggregateIntrinsicValueOutstanding	18372000	USD
	cbsh	Percentof Revenuenotinscopeof Asc606 PercentofRevenuenotinscopeofASC606	0.60
CY2021Q3	us-gaap	Noninterest Income NoninterestIncome	137506000	USD
CY2020Q3	us-gaap	Noninterest Income NoninterestIncome	129572000	USD
	us-gaap	Noninterest Income NoninterestIncome	412694000	USD
	us-gaap	Noninterest Income NoninterestIncome	370750000	USD
CY2021Q3	us-gaap	Mortgages Held For Sale Fair Value Disclosure MortgagesHeldForSaleFairValueDisclosure	11982000	USD
CY2021Q3	us-gaap	Financial Instruments Owned Us Government And Agency Obligations At Fair Value FinancialInstrumentsOwnedUSGovernmentAndAgencyObligationsAtFairValue	784190000	USD
CY2021Q3	cbsh	Us Government Sponsored Enterprises Debt Securities USGovernmentSponsoredEnterprisesDebtSecurities	51941000	USD
CY2021Q3	us-gaap	Financial Instruments Owned State And Municipal Government Obligations At Fair Value FinancialInstrumentsOwnedStateAndMunicipalGovernmentObligationsAtFairValue	2155076000	USD
CY2021Q3	cbsh	Financial Instruments Owned Agency Mortgage Backed Securities At Fair Value FinancialInstrumentsOwnedAgencyMortgageBackedSecuritiesAtFairValue	5974802000	USD
CY2021Q3	cbsh	Financial Instruments Owned Non Agency Mortgage Backed Securities At Fair Value FinancialInstrumentsOwnedNonAgencyMortgageBackedSecuritiesAtFairValue	1225091000	USD
CY2021Q3	cbsh	Other Asset Backed Securities Disclosure OtherAssetBackedSecuritiesDisclosure	3359915000	USD
CY2021Q3	cbsh	Financial Instruments Owned Other Debt Securities At Fair Value FinancialInstrumentsOwnedOtherDebtSecuritiesAtFairValue	614641000	USD
CY2021Q3	us-gaap	Trading Securities TradingSecurities	40114000	USD
CY2021Q3	us-gaap	Equity Securities Fv Ni EquitySecuritiesFvNi	7118000	USD
CY2021Q3	us-gaap	Financial Instruments Owned Principal Investments At Fair Value FinancialInstrumentsOwnedPrincipalInvestmentsAtFairValue	138052000	USD
CY2021Q3	us-gaap	Derivative Assets DerivativeAssets	55065000	USD
CY2021Q3	us-gaap	Deferred Compensation Plan Assets DeferredCompensationPlanAssets	20880000	USD
CY2021Q3	us-gaap	Assets Fair Value Disclosure AssetsFairValueDisclosure	14438867000	USD
CY2021Q3	us-gaap	Derivative Liabilities DerivativeLiabilities	12466000	USD
CY2021Q3	us-gaap	Deferred Compensation Liability Current And Noncurrent DeferredCompensationLiabilityCurrentAndNoncurrent	20880000	USD
CY2021Q3	us-gaap	Liabilities Fair Value Disclosure LiabilitiesFairValueDisclosure	33346000	USD
CY2020Q4	us-gaap	Mortgages Held For Sale Fair Value Disclosure MortgagesHeldForSaleFairValueDisclosure	39396000	USD
CY2020Q4	us-gaap	Financial Instruments Owned Us Government And Agency Obligations At Fair Value FinancialInstrumentsOwnedUSGovernmentAndAgencyObligationsAtFairValue	838059000	USD
CY2020Q4	cbsh	Us Government Sponsored Enterprises Debt Securities USGovernmentSponsoredEnterprisesDebtSecurities	54485000	USD
CY2020Q4	us-gaap	Financial Instruments Owned State And Municipal Government Obligations At Fair Value FinancialInstrumentsOwnedStateAndMunicipalGovernmentObligationsAtFairValue	2045099000	USD
CY2020Q4	cbsh	Financial Instruments Owned Agency Mortgage Backed Securities At Fair Value FinancialInstrumentsOwnedAgencyMortgageBackedSecuritiesAtFairValue	6712085000	USD
CY2020Q4	cbsh	Financial Instruments Owned Non Agency Mortgage Backed Securities At Fair Value FinancialInstrumentsOwnedNonAgencyMortgageBackedSecuritiesAtFairValue	361074000	USD
CY2020Q4	cbsh	Other Asset Backed Securities Disclosure OtherAssetBackedSecuritiesDisclosure	1882243000	USD
CY2020Q4	cbsh	Financial Instruments Owned Other Debt Securities At Fair Value FinancialInstrumentsOwnedOtherDebtSecuritiesAtFairValue	556219000	USD
CY2020Q4	us-gaap	Trading Securities TradingSecurities	35321000	USD
CY2020Q4	us-gaap	Equity Securities Fv Ni EquitySecuritiesFvNi	2966000	USD
CY2020Q4	us-gaap	Financial Instruments Owned Principal Investments At Fair Value FinancialInstrumentsOwnedPrincipalInvestmentsAtFairValue	94368000	USD
CY2020Q4	us-gaap	Derivative Assets DerivativeAssets	89889000	USD
CY2020Q4	us-gaap	Deferred Compensation Plan Assets DeferredCompensationPlanAssets	19278000	USD
CY2020Q4	us-gaap	Assets Fair Value Disclosure AssetsFairValueDisclosure	12730482000	USD
CY2020Q4	us-gaap	Derivative Liabilities DerivativeLiabilities	18675000	USD
CY2020Q4	us-gaap	Deferred Compensation Liability Current And Noncurrent DeferredCompensationLiabilityCurrentAndNoncurrent	19278000	USD
CY2020Q4	us-gaap	Liabilities Fair Value Disclosure LiabilitiesFairValueDisclosure	37953000	USD
CY2021Q2	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Value FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue	125866000	USD
CY2021Q3	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Gain Loss Included In Earnings1 FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInEarnings1	-12709000	USD
CY2021Q3	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Gain Loss Included In Other Comprehensive Income Loss FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInOtherComprehensiveIncomeLoss	-175000	USD
CY2021Q3	cbsh	Investment Securities Called InvestmentSecuritiesCalled	6000000	USD
CY2021Q3	cbsh	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Discount Accretion FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetDiscountAccretion	179000	USD
CY2021Q3	cbsh	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Purchase Of Private Equity Securities FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetPurchaseOfPrivateEquitySecurities	8835000	USD
CY2021Q3	cbsh	Sale Of Risk Participation Agreement SaleOfRiskParticipationAgreement	27000	USD
CY2021Q3	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Value FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue	141387000	USD
CY2021Q3	cbsh	Change In Unrealized Gains Or Losses Related To Assets Held Level3 Fair Value Measurements ChangeInUnrealizedGainsOrLossesRelatedToAssetsHeldLevel3FairValueMeasurements	14528000	USD
CY2021Q3	cbsh	Gains Losses Included In Oci Attributable To Change In Unrealized Gains Losses Relating To Assets Still Held Total GainsLossesIncludedInOCIAttributableToChangeInUnrealizedGainsLossesRelatingToAssetsStillHeldTotal	2000	USD
CY2020Q4	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Value FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue	105077000	USD
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	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Gain Loss Included In Other Comprehensive Income Loss FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInOtherComprehensiveIncomeLoss	-158000	USD
	cbsh	Investment Securities Called InvestmentSecuritiesCalled	6000000	USD
	cbsh	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Discount Accretion FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetDiscountAccretion	185000	USD
	cbsh	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Purchase Of Private Equity Securities FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetPurchaseOfPrivateEquitySecurities	14491000	USD
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	cbsh	Sales And Repayments Of Private Equity Securities SalesAndRepaymentsOfPrivateEquitySecurities	8832000	USD
	cbsh	Capitalized Interest Or Dividends CapitalizedInterestOrDividends	23000	USD
	cbsh	Purchase Of Risk Participation Agreement PurchaseOfRiskParticipationAgreement	445000	USD
	cbsh	Sale Of Risk Participation Agreement SaleOfRiskParticipationAgreement	157000	USD
CY2021Q3	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Value FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue	141387000	USD
	cbsh	Change In Unrealized Gains Or Losses Related To Assets Held Level3 Fair Value Measurements ChangeInUnrealizedGainsOrLossesRelatedToAssetsHeldLevel3FairValueMeasurements	39369000	USD
	cbsh	Gains Losses Included In Oci Attributable To Change In Unrealized Gains Losses Relating To Assets Still Held Total GainsLossesIncludedInOCIAttributableToChangeInUnrealizedGainsLossesRelatingToAssetsStillHeldTotal	23000	USD
CY2020Q2	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Value FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue	85224000	USD
CY2020Q3	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Gain Loss Included In Earnings1 FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInEarnings1	-2893000	USD
CY2020Q3	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Gain Loss Included In Other Comprehensive Income Loss FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInOtherComprehensiveIncomeLoss	271000	USD
CY2020Q3	cbsh	Investment Securities Called InvestmentSecuritiesCalled	2000000	USD
CY2020Q3	cbsh	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Discount Accretion FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetDiscountAccretion	105000	USD
CY2020Q3	cbsh	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Purchase Of Private Equity Securities FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetPurchaseOfPrivateEquitySecurities	2522000	USD
CY2020Q3	cbsh	Sales And Repayments Of Private Equity Securities SalesAndRepaymentsOfPrivateEquitySecurities	295000	USD
CY2020Q3	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Value FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue	88720000	USD
CY2020Q3	cbsh	Change In Unrealized Gains Or Losses Related To Assets Held Level3 Fair Value Measurements ChangeInUnrealizedGainsOrLossesRelatedToAssetsHeldLevel3FairValueMeasurements	5459000	USD
CY2020Q3	cbsh	Gains Losses Included In Oci Attributable To Change In Unrealized Gains Losses Relating To Assets Still Held Total GainsLossesIncludedInOCIAttributableToChangeInUnrealizedGainsLossesRelatingToAssetsStillHeldTotal	258000	USD
CY2019Q4	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Value FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue	104344000	USD
	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Gain Loss Included In Earnings1 FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInEarnings1	15284000	USD
	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Gain Loss Included In Other Comprehensive Income Loss FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInOtherComprehensiveIncomeLoss	-101000	USD
	cbsh	Investment Securities Called InvestmentSecuritiesCalled	2000000	USD
	cbsh	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Discount Accretion FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetDiscountAccretion	114000	USD
	cbsh	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Purchase Of Private Equity Securities FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetPurchaseOfPrivateEquitySecurities	2791000	USD
	cbsh	Sales And Repayments Of Private Equity Securities SalesAndRepaymentsOfPrivateEquitySecurities	364000	USD
	cbsh	Capitalized Interest Or Dividends CapitalizedInterestOrDividends	29000	USD
	cbsh	Sale Of Risk Participation Agreement SaleOfRiskParticipationAgreement	809000	USD
CY2020Q3	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Value FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue	88720000	USD
	cbsh	Change In Unrealized Gains Or Losses Related To Assets Held Level3 Fair Value Measurements ChangeInUnrealizedGainsOrLossesRelatedToAssetsHeldLevel3FairValueMeasurements	-14834000	USD
	cbsh	Gains Losses Included In Oci Attributable To Change In Unrealized Gains Losses Relating To Assets Still Held Total GainsLossesIncludedInOCIAttributableToChangeInUnrealizedGainsLossesRelatingToAssetsStillHeldTotal	-52000	USD
CY2021Q3	cbsh	Total Gains Or Losses Included In Earnings Level3 Fair Measurements TotalGainsOrLossesIncludedInEarningsLevel3FairMeasurements	12709000	USD
CY2021Q3	cbsh	Change In Unrealized Gains Or Losses Related To Assets Held Level3 Fair Value Measurements ChangeInUnrealizedGainsOrLossesRelatedToAssetsHeldLevel3FairValueMeasurements	14528000	USD
	cbsh	Total Gains Or Losses Included In Earnings Level3 Fair Measurements TotalGainsOrLossesIncludedInEarningsLevel3FairMeasurements	36313000	USD
	cbsh	Change In Unrealized Gains Or Losses Related To Assets Held Level3 Fair Value Measurements ChangeInUnrealizedGainsOrLossesRelatedToAssetsHeldLevel3FairValueMeasurements	39369000	USD
CY2020Q3	cbsh	Total Gains Or Losses Included In Earnings Level3 Fair Measurements TotalGainsOrLossesIncludedInEarningsLevel3FairMeasurements	2893000	USD
CY2020Q3	cbsh	Change In Unrealized Gains Or Losses Related To Assets Held Level3 Fair Value Measurements ChangeInUnrealizedGainsOrLossesRelatedToAssetsHeldLevel3FairValueMeasurements	5459000	USD
	cbsh	Total Gains Or Losses Included In Earnings Level3 Fair Measurements TotalGainsOrLossesIncludedInEarningsLevel3FairMeasurements	-15284000	USD
	cbsh	Change In Unrealized Gains Or Losses Related To Assets Held Level3 Fair Value Measurements ChangeInUnrealizedGainsOrLossesRelatedToAssetsHeldLevel3FairValueMeasurements	-14834000	USD
CY2021Q3	cbsh	Loans Nonrecurring Basis LoansNonrecurringBasis	2057000	USD
	cbsh	Loans Nonrecurring Basis Gains Losses LoansNonrecurringBasisGainsLosses	-349000	USD
CY2021Q3	cbsh	Mortgage Servicing Rights Nonrecurring Basis MortgageServicingRightsNonrecurringBasis	9774000	USD
	cbsh	Mortgage Servicing Rights Nonrecurring Basis Gains Losses MortgageServicingRightsNonrecurringBasisGainsLosses	1120000	USD
CY2021Q3	cbsh	Long Lived Assets Nonrecurring Basis LongLivedAssetsNonrecurringBasis	1393000	USD
	cbsh	Long Lived Assets Nonrecurring Basis Gains Losses LongLivedAssetsNonrecurringBasisGainsLosses	-726000	USD
CY2020Q3	cbsh	Loans Nonrecurring Basis LoansNonrecurringBasis	11772000	USD
	cbsh	Loans Nonrecurring Basis Gains Losses LoansNonrecurringBasisGainsLosses	-3214000	USD
CY2020Q3	cbsh	Mortgage Servicing Rights Nonrecurring Basis MortgageServicingRightsNonrecurringBasis	5731000	USD
	cbsh	Mortgage Servicing Rights Nonrecurring Basis Gains Losses MortgageServicingRightsNonrecurringBasisGainsLosses	-1823000	USD
	cbsh	Fair Value Discounted Cash Flow Valuation Techniques FairValueDiscountedCashFlowValuationTechniques	Discounted cash flow

Files In Submission

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$CBSH
COMMERCE BANCSHARES INC /MO/ Stock $cbsh

2021 Q4 Form 10-Q Financial Statement

#000002235621000046 Filed on November 05, 2021

Income Statement

Balance Sheet

Cashflow Statement

Facts In Submission

Files In Submission

$CBSH COMMERCE BANCSHARES INC /MO/ Stock $cbsh

2021 Q4 Form 10-Q Financial Statement

#000002235621000046 Filed on November 05, 2021

Income Statement

Balance Sheet

Cashflow Statement

Facts In Submission

Files In Submission

$CBSH
COMMERCE BANCSHARES INC /MO/ Stock $cbsh