$CBSH
COMMERCE BANCSHARES INC /MO/ Stock $cbsh

$cbsh Overview Financials Valuation SEC Filings Company Website

2021 Q2 Form 10-Q Financial Statement

#000002235621000033 Filed on May 06, 2021

Income Statement

Concept	2021 Q2	2021 Q1	2020 Q1
Revenue	$0.00	$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	$11.10M	$11.40M	$10.60M
YoY Change	3.74%	7.55%	6.0%
% of Gross Profit
Operating Expenses
YoY Change
Operating Profit
YoY Change
Interest Expense	$3.151M	$3.949M	$20.42M
YoY Change	-69.31%	-80.66%	-16.23%
% of Operating Profit
Other Income/Expense, Net
YoY Change
Pretax Income	$211.5M	$165.3M	$59.78M
YoY Change	336.97%	176.54%	-50.15%
Income Tax	$45.21M	$32.08M	$10.17M
% Of Pretax Income	21.38%	19.4%	17.02%
Net Earnings	$162.3M	$131.0M	$51.86M
YoY Change	307.21%	152.56%	-46.62%
Net Earnings / Revenue
Basic Earnings Per Share	$1.32	$1.06	$0.42
Diluted Earnings Per Share	$1.32	$1.06	$0.42
COMMON SHARES
Basic Shares Outstanding	117.0M shares	117.1M shares	112.1M shares
Diluted Shares Outstanding

Balance Sheet

Concept	2021 Q2	2021 Q1	2020 Q1
SHORT-TERM ASSETS
Cash & Short-Term Investments
YoY Change
Cash & Equivalents	$2.546B	$2.381B	$899.5M
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	$372.0M	$371.7M	$369.7M
YoY Change	0.93%	0.54%	1.95%
Goodwill	$138.9M	$138.9M	$138.9M
YoY Change	0.0%	0.0%	0.0%
Intangibles	$14.15M	$13.10M	$8.433M
YoY Change	97.07%	55.32%	-0.92%
Long-Term Investments	$15.84M	$17.31M
YoY Change
Other Assets
YoY Change
Total Long-Term Assets
YoY Change
TOTAL ASSETS
Total Short-Term Assets
Total Long-Term Assets
Total Assets	$33.86B	$33.27B	$26.79B
YoY Change	11.02%	24.17%	7.03%
SHORT-TERM LIABILITIES
YoY Change
Accounts Payable
YoY Change
Accrued Expenses
YoY Change
Deferred Revenue
YoY Change
Short-Term Debt	$2.318B	$1.938B	$1.428B
YoY Change	33.22%	35.71%	-17.12%
Long-Term Debt Due
YoY Change
Total Short-Term Liabilities	$2.318B	$1.938B	$1.428B
YoY Change	33.22%	35.71%	5000.0%
LONG-TERM LIABILITIES
Long-Term Debt	$2.000M	$4.000M	$756.0M
YoY Change	100.0%	-99.47%	37700.0%
Other Long-Term Liabilities	$556.0M	$590.0M	$580.0M
YoY Change	-36.02%	1.72%	120.53%
Total Long-Term Liabilities	$558.0M	$594.0M	$1.336B
YoY Change	-35.86%	-55.54%	404.15%
TOTAL LIABILITIES
Total Short-Term Liabilities	$2.318B	$1.938B	$1.428B
Total Long-Term Liabilities	$558.0M	$594.0M	$1.336B
Total Liabilities	$30.36B	$29.95B	$23.54B
YoY Change	11.88%	27.24%	7.05%
SHAREHOLDERS EQUITY
Retained Earnings	$304.7M	$173.2M	$224.6M
YoY Change	31.31%	-22.91%	-26.87%
Common Stock	$589.4M	$589.4M	$564.0M
YoY Change	4.5%	4.5%	0.81%
Preferred Stock
YoY Change
Treasury Stock (at cost)	$53.02M	$39.08M	$69.15M
YoY Change	-23.29%	-43.48%	14.21%
Treasury Stock Shares	742.8K shares	560.2K shares	1.040M shares
Shareholders Equity	$3.486B	$3.313B	$3.251B
YoY Change
Total Liabilities & Shareholders Equity	$33.86B	$33.27B	$26.79B
YoY Change	11.02%	24.17%	7.03%

Cashflow Statement

Concept	2021 Q2	2021 Q1	2020 Q1
OPERATING ACTIVITIES
Net Income	$162.3M	$131.0M	$51.86M
YoY Change	307.21%	152.56%	-46.62%
Depreciation, Depletion And Amortization	$11.10M	$11.40M	$10.60M
YoY Change	3.74%	7.55%	6.0%
Cash From Operating Activities	$125.5M	$201.7M	$79.77M
YoY Change	-16.28%	152.82%	-43.9%
INVESTING ACTIVITIES
Capital Expenditures	-$11.20M	$10.73M	$7.574M
YoY Change	83.61%	41.67%	-32.87%
Acquisitions
YoY Change
Other Investing Activities	-$357.2M	-$317.0M	-$274.0M
YoY Change	-86.53%	15.69%	1270.0%
Cash From Investing Activities	-$368.5M	-$327.7M	-$281.6M
YoY Change	-86.14%	16.38%	799.03%
FINANCING ACTIVITIES
Cash Dividend Paid
YoY Change
Common Stock Issuance & Retirement, Net		$25.92M	$53.15M
YoY Change		-51.22%	33.87%
Debt Paid & Issued, Net			$0.00
YoY Change			-100.0%
Cash From Financing Activities	408.3M	$298.6M	$193.5M
YoY Change	-88.08%	54.27%	-127.12%
NET CHANGE
Cash From Operating Activities	125.5M	$201.7M	$79.77M
Cash From Investing Activities	-368.5M	-$327.7M	-$281.6M
Cash From Financing Activities	408.3M	$298.6M	$193.5M
Net Change In Cash	165.3M	$172.5M	-$8.294M
YoY Change	-82.01%	-2179.77%	-98.62%
FREE CASH FLOW
Cash From Operating Activities	$125.5M	$201.7M	$79.77M
Capital Expenditures	-$11.20M	$10.73M	$7.574M
Free Cash Flow	$136.7M	$190.9M	$72.19M
YoY Change	-12.37%	164.48%	-44.85%

Facts In Submission

Frame	Concept Type	Concept / XBRL Key	Value	Unit
CY2021Q1	dei	Entity Central Index Key EntityCentralIndexKey	0000022356
CY2021Q1	dei	Current Fiscal Year End Date CurrentFiscalYearEndDate	--12-31
CY2021Q1	cbsh	Student Loans Heldfor Sale Lowerof Costor Fair Value StudentLoansHeldforSaleLowerofCostorFairValue	7600000	USD
CY2021Q1	dei	Document Fiscal Year Focus DocumentFiscalYearFocus	2021
CY2021Q1	dei	Document Fiscal Period Focus DocumentFiscalPeriodFocus	Q1
CY2021Q1	dei	Amendment Flag AmendmentFlag	false
CY2020Q4	us-gaap	Available For Sale Debt Securities Amortized Cost Basis AvailableForSaleDebtSecuritiesAmortizedCostBasis	12097533000	USD
CY2020Q4	us-gaap	Debt Securities Available For Sale Allowance For Credit Loss DebtSecuritiesAvailableForSaleAllowanceForCreditLoss	0	USD
CY2021Q1	us-gaap	Preferred Stock Dividends Per Share Cash Paid PreferredStockDividendsPerShareCashPaid	0
CY2021Q1	cbsh	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Purchase Of Private Equity Securities FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetPurchaseOfPrivateEquitySecurities	0	USD
CY2021Q1	dei	Document Type DocumentType	10-Q
CY2021Q1	dei	Document Quarterly Report DocumentQuarterlyReport	true
CY2021Q1	dei	Document Period End Date DocumentPeriodEndDate	2021-03-31
CY2021Q1	dei	Document Transition Report DocumentTransitionReport	false
CY2021Q1	dei	Entity File Number EntityFileNumber	001-36502
CY2021Q1	dei	Entity Registrant Name EntityRegistrantName	COMMERCE BANCSHARES, INC.
CY2021Q1	dei	Entity Incorporation State Country Code EntityIncorporationStateCountryCode	MO
CY2021Q1	dei	Entity Tax Identification Number EntityTaxIdentificationNumber	43-0889454
CY2021Q1	dei	Entity Address Address Line1 EntityAddressAddressLine1	1000 Walnut
CY2021Q1	dei	Entity Address City Or Town EntityAddressCityOrTown	Kansas City,
CY2021Q1	dei	Entity Address State Or Province EntityAddressStateOrProvince	MO
CY2021Q1	dei	Entity Address Postal Zip Code EntityAddressPostalZipCode	64106
CY2021Q1	dei	City Area Code CityAreaCode	816
CY2021Q1	dei	Local Phone Number LocalPhoneNumber	234-2000
CY2021Q1	dei	Security12b Title Security12bTitle	$5 Par Value Common Stock
CY2021Q1	dei	Trading Symbol TradingSymbol	CBSH
CY2021Q1	dei	Security Exchange Name SecurityExchangeName	NASDAQ
CY2021Q1	dei	Entity Current Reporting Status EntityCurrentReportingStatus	Yes
CY2021Q1	dei	Entity Interactive Data Current EntityInteractiveDataCurrent	Yes
CY2021Q1	dei	Entity Filer Category EntityFilerCategory	Large Accelerated Filer
CY2021Q1	dei	Entity Small Business EntitySmallBusiness	false
CY2021Q1	dei	Entity Emerging Growth Company EntityEmergingGrowthCompany	false
CY2021Q1	dei	Entity Shell Company EntityShellCompany	false
CY2021Q2	dei	Entity Common Stock Shares Outstanding EntityCommonStockSharesOutstanding	117034676	shares
CY2021Q1	us-gaap	Loans And Leases Receivable Net Of Deferred Income LoansAndLeasesReceivableNetOfDeferredIncome	16392071000	USD
CY2020Q4	us-gaap	Loans And Leases Receivable Net Of Deferred Income LoansAndLeasesReceivableNetOfDeferredIncome	16329641000	USD
CY2021Q1	us-gaap	Financing Receivable Allowance For Credit Losses FinancingReceivableAllowanceForCreditLosses	200527000	USD
CY2020Q4	us-gaap	Financing Receivable Allowance For Credit Losses FinancingReceivableAllowanceForCreditLosses	220834000	USD
CY2021Q1	us-gaap	Loans And Leases Receivable Net Reported Amount LoansAndLeasesReceivableNetReportedAmount	16191544000	USD
CY2020Q4	us-gaap	Loans And Leases Receivable Net Reported Amount LoansAndLeasesReceivableNetReportedAmount	16108807000	USD
CY2021Q1	us-gaap	Mortgages Held For Sale Fair Value Disclosure MortgagesHeldForSaleFairValueDisclosure	30505000	USD
CY2020Q4	us-gaap	Mortgages Held For Sale Fair Value Disclosure MortgagesHeldForSaleFairValueDisclosure	39396000	USD
CY2021Q1	us-gaap	Loans Receivable Held For Sale Amount LoansReceivableHeldForSaleAmount	38076000	USD
CY2020Q4	us-gaap	Loans Receivable Held For Sale Amount LoansReceivableHeldForSaleAmount	45089000	USD
CY2021Q1	us-gaap	Available For Sale Debt Securities Amortized Cost Basis AvailableForSaleDebtSecuritiesAmortizedCostBasis	12388041000	USD
CY2020Q4	us-gaap	Available For Sale Debt Securities Amortized Cost Basis AvailableForSaleDebtSecuritiesAmortizedCostBasis	12097533000	USD
CY2021Q1	us-gaap	Debt Securities Available For Sale Allowance For Credit Loss DebtSecuritiesAvailableForSaleAllowanceForCreditLoss	0	USD
CY2021Q1	us-gaap	Available For Sale Securities Debt Securities AvailableForSaleSecuritiesDebtSecurities	12528203000	USD
CY2020Q4	us-gaap	Available For Sale Securities Debt Securities AvailableForSaleSecuritiesDebtSecurities	12449264000	USD
CY2021Q1	us-gaap	Trading Securities TradingSecurities	26925000	USD
CY2020Q4	us-gaap	Trading Securities TradingSecurities	35321000	USD
CY2021Q1	us-gaap	Equity Securities Fv Ni And Without Readily Determinable Fair Value EquitySecuritiesFvNiAndWithoutReadilyDeterminableFairValue	4337000	USD
CY2020Q4	us-gaap	Equity Securities Fv Ni And Without Readily Determinable Fair Value EquitySecuritiesFvNiAndWithoutReadilyDeterminableFairValue	4363000	USD
CY2021Q1	cbsh	Other Securities OtherSecurities	155913000	USD
CY2020Q4	cbsh	Other Securities OtherSecurities	156745000	USD
CY2021Q1	cbsh	Total Investment Securities TotalInvestmentSecurities	12715378000	USD
CY2020Q4	cbsh	Total Investment Securities TotalInvestmentSecurities	12645693000	USD
CY2021Q1	us-gaap	Federal Funds Sold And Securities Purchased Under Agreements To Resell FederalFundsSoldAndSecuritiesPurchasedUnderAgreementsToResell	500000	USD
CY2020Q4	us-gaap	Federal Funds Sold And Securities Purchased Under Agreements To Resell FederalFundsSoldAndSecuritiesPurchasedUnderAgreementsToResell	0	USD
CY2021Q1	cbsh	Long Term Securities Purchased Under Agreements To Resell LongTermSecuritiesPurchasedUnderAgreementsToResell	850000000	USD
CY2020Q4	cbsh	Long Term Securities Purchased Under Agreements To Resell LongTermSecuritiesPurchasedUnderAgreementsToResell	850000000	USD
CY2021Q1	us-gaap	Interest Bearing Deposits In Banks InterestBearingDepositsInBanks	2017128000	USD
CY2020Q4	us-gaap	Interest Bearing Deposits In Banks InterestBearingDepositsInBanks	1747363000	USD
CY2021Q1	us-gaap	Cash And Due From Banks CashAndDueFromBanks	338666000	USD
CY2020Q4	us-gaap	Cash And Due From Banks CashAndDueFromBanks	437563000	USD
CY2021Q1	us-gaap	Property Plant And Equipment Net PropertyPlantAndEquipmentNet	371737000	USD
CY2020Q4	us-gaap	Property Plant And Equipment Net PropertyPlantAndEquipmentNet	371083000	USD
CY2021Q1	us-gaap	Goodwill Goodwill	138921000	USD
CY2020Q4	us-gaap	Goodwill Goodwill	138921000	USD
CY2021Q1	us-gaap	Intangible Assets Net Excluding Goodwill IntangibleAssetsNetExcludingGoodwill	13098000	USD
CY2020Q4	us-gaap	Intangible Assets Net Excluding Goodwill IntangibleAssetsNetExcludingGoodwill	11207000	USD
CY2021Q1	us-gaap	Other Assets OtherAssets	594738000	USD
CY2020Q4	us-gaap	Other Assets OtherAssets	567248000	USD
CY2021Q1	us-gaap	Assets Assets	33269786000	USD
CY2020Q4	us-gaap	Assets Assets	32922974000	USD
CY2021Q1	us-gaap	Noninterest Bearing Deposit Liabilities NoninterestBearingDepositLiabilities	11076556000	USD
CY2020Q4	us-gaap	Noninterest Bearing Deposit Liabilities NoninterestBearingDepositLiabilities	10497598000	USD
CY2021Q1	us-gaap	Interest Bearing Deposit Liabilities InterestBearingDepositLiabilities	14572378000	USD
CY2020Q4	us-gaap	Interest Bearing Deposit Liabilities InterestBearingDepositLiabilities	14604456000	USD
CY2021Q1	us-gaap	Time Deposits Less Than100000 TimeDepositsLessThan100000	504472000	USD
CY2020Q4	us-gaap	Time Deposits Less Than100000 TimeDepositsLessThan100000	529802000	USD
CY2021Q1	us-gaap	Time Deposits100000 Or More TimeDeposits100000OrMore	1267219000	USD
CY2020Q4	us-gaap	Time Deposits100000 Or More TimeDeposits100000OrMore	1314889000	USD
CY2021Q1	us-gaap	Deposits Deposits	27420625000	USD
CY2020Q4	us-gaap	Deposits Deposits	26946745000	USD
CY2021Q1	us-gaap	Federal Funds Purchased And Securities Sold Under Agreements To Repurchase FederalFundsPurchasedAndSecuritiesSoldUnderAgreementsToRepurchase	1938110000	USD
CY2020Q4	us-gaap	Federal Funds Purchased And Securities Sold Under Agreements To Repurchase FederalFundsPurchasedAndSecuritiesSoldUnderAgreementsToRepurchase	2098383000	USD
CY2021Q1	us-gaap	Other Borrowings OtherBorrowings	3791000	USD
CY2020Q4	us-gaap	Other Borrowings OtherBorrowings	802000	USD
CY2021Q1	us-gaap	Other Liabilities OtherLiabilities	589875000	USD
CY2020Q4	us-gaap	Other Liabilities OtherLiabilities	477072000	USD
CY2021Q1	us-gaap	Liabilities Liabilities	29952401000	USD
CY2020Q4	us-gaap	Liabilities Liabilities	29523002000	USD
CY2021Q1	us-gaap	Common Stock Par Or Stated Value Per Share CommonStockParOrStatedValuePerShare	5
CY2020Q4	us-gaap	Common Stock Par Or Stated Value Per Share CommonStockParOrStatedValuePerShare	5
CY2021Q1	us-gaap	Common Stock Shares Authorized CommonStockSharesAuthorized	140000000	shares
CY2020Q4	us-gaap	Common Stock Shares Authorized CommonStockSharesAuthorized	140000000	shares
CY2021Q1	us-gaap	Common Stock Shares Issued CommonStockSharesIssued	117870372	shares
CY2020Q4	us-gaap	Common Stock Shares Issued CommonStockSharesIssued	117870372	shares
CY2021Q1	us-gaap	Common Stock Value CommonStockValue	589352000	USD
CY2020Q4	us-gaap	Common Stock Value CommonStockValue	589352000	USD
CY2021Q1	us-gaap	Additional Paid In Capital AdditionalPaidInCapital	2420393000	USD
CY2020Q4	us-gaap	Additional Paid In Capital AdditionalPaidInCapital	2436288000	USD
CY2021Q1	us-gaap	Retained Earnings Accumulated Deficit RetainedEarningsAccumulatedDeficit	173173000	USD
CY2020Q4	us-gaap	Retained Earnings Accumulated Deficit RetainedEarningsAccumulatedDeficit	73000000	USD
CY2021Q1	us-gaap	Treasury Stock Shares TreasuryStockShares	560185	shares
CY2020Q4	us-gaap	Treasury Stock Shares TreasuryStockShares	497413	shares
CY2021Q1	us-gaap	Treasury Stock Value TreasuryStockValue	39080000	USD
CY2020Q4	us-gaap	Treasury Stock Value TreasuryStockValue	32970000	USD
CY2021Q1	us-gaap	Accumulated Other Comprehensive Income Loss Net Of Tax AccumulatedOtherComprehensiveIncomeLossNetOfTax	168752000	USD
CY2020Q4	us-gaap	Accumulated Other Comprehensive Income Loss Net Of Tax AccumulatedOtherComprehensiveIncomeLossNetOfTax	331377000	USD
CY2021Q1	us-gaap	Stockholders Equity StockholdersEquity	3312590000	USD
CY2020Q4	us-gaap	Stockholders Equity StockholdersEquity	3397047000	USD
CY2021Q1	us-gaap	Minority Interest MinorityInterest	4795000	USD
CY2020Q4	us-gaap	Minority Interest MinorityInterest	2925000	USD
CY2021Q1	us-gaap	Stockholders Equity Including Portion Attributable To Noncontrolling Interest StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest	3317385000	USD
CY2020Q4	us-gaap	Stockholders Equity Including Portion Attributable To Noncontrolling Interest StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest	3399972000	USD
CY2021Q1	us-gaap	Liabilities And Stockholders Equity LiabilitiesAndStockholdersEquity	33269786000	USD
CY2020Q4	us-gaap	Liabilities And Stockholders Equity LiabilitiesAndStockholdersEquity	32922974000	USD
CY2021Q1	us-gaap	Interest And Fee Income Loans And Leases Held In Portfolio InterestAndFeeIncomeLoansAndLeasesHeldInPortfolio	146338000	USD
CY2020Q1	us-gaap	Interest And Fee Income Loans And Leases Held In Portfolio InterestAndFeeIncomeLoansAndLeasesHeldInPortfolio	159147000	USD
CY2021Q1	us-gaap	Interest And Fee Income Loans And Leases Held For Sale InterestAndFeeIncomeLoansAndLeasesHeldForSale	304000	USD
CY2020Q1	us-gaap	Interest And Fee Income Loans And Leases Held For Sale InterestAndFeeIncomeLoansAndLeasesHeldForSale	197000	USD
CY2021Q1	us-gaap	Interest And Dividend Income Securities InterestAndDividendIncomeSecurities	51557000	USD
CY2020Q1	us-gaap	Interest And Dividend Income Securities InterestAndDividendIncomeSecurities	53385000	USD
CY2021Q1	us-gaap	Interest Income Federal Funds Sold And Securities Purchased Under Agreements To Resell InterestIncomeFederalFundsSoldAndSecuritiesPurchasedUnderAgreementsToResell	0	USD
CY2020Q1	us-gaap	Interest Income Federal Funds Sold And Securities Purchased Under Agreements To Resell InterestIncomeFederalFundsSoldAndSecuritiesPurchasedUnderAgreementsToResell	2000	USD
CY2021Q1	cbsh	Interest On Long Term Securities Purchased Under Agreements To Resell InterestOnLongTermSecuritiesPurchasedUnderAgreementsToResell	11128000	USD
CY2020Q1	cbsh	Interest On Long Term Securities Purchased Under Agreements To Resell InterestOnLongTermSecuritiesPurchasedUnderAgreementsToResell	7462000	USD
CY2021Q1	us-gaap	Interest Income Deposits With Financial Institutions InterestIncomeDepositsWithFinancialInstitutions	370000	USD
CY2020Q1	us-gaap	Interest Income Deposits With Financial Institutions InterestIncomeDepositsWithFinancialInstitutions	1292000	USD
CY2021Q1	us-gaap	Interest And Dividend Income Operating InterestAndDividendIncomeOperating	209697000	USD
CY2020Q1	us-gaap	Interest And Dividend Income Operating InterestAndDividendIncomeOperating	221485000	USD
CY2021Q1	us-gaap	Interest Expense Now Accounts Money Market Accounts And Savings Deposits InterestExpenseNOWAccountsMoneyMarketAccountsAndSavingsDeposits	2103000	USD
CY2020Q1	us-gaap	Interest Expense Now Accounts Money Market Accounts And Savings Deposits InterestExpenseNOWAccountsMoneyMarketAccountsAndSavingsDeposits	8309000	USD
CY2021Q1	us-gaap	Interest Expense Time Deposits Less Than100000 InterestExpenseTimeDepositsLessThan100000	473000	USD
CY2020Q1	us-gaap	Interest Expense Time Deposits Less Than100000 InterestExpenseTimeDepositsLessThan100000	1775000	USD
CY2021Q1	us-gaap	Interest Expense Time Deposits100000 Or More InterestExpenseTimeDeposits100000OrMore	1062000	USD
CY2020Q1	us-gaap	Interest Expense Time Deposits100000 Or More InterestExpenseTimeDeposits100000OrMore	5235000	USD
CY2021Q1	us-gaap	Interest Expense Federal Funds Purchased And Securities Sold Under Agreements To Repurchase InterestExpenseFederalFundsPurchasedAndSecuritiesSoldUnderAgreementsToRepurchase	312000	USD
CY2020Q1	us-gaap	Interest Expense Federal Funds Purchased And Securities Sold Under Agreements To Repurchase InterestExpenseFederalFundsPurchasedAndSecuritiesSoldUnderAgreementsToRepurchase	4770000	USD
CY2021Q1	cbsh	Interest On Other Borrowings InterestOnOtherBorrowings	-1000	USD
CY2020Q1	cbsh	Interest On Other Borrowings InterestOnOtherBorrowings	331000	USD
CY2021Q1	us-gaap	Interest Expense InterestExpense	3949000	USD
CY2020Q1	us-gaap	Interest Expense InterestExpense	20420000	USD
CY2021Q1	us-gaap	Interest Income Expense Net InterestIncomeExpenseNet	205748000	USD
CY2020Q1	us-gaap	Interest Income Expense Net InterestIncomeExpenseNet	201065000	USD
CY2021Q1	us-gaap	Provision For Loan And Lease Losses ProvisionForLoanAndLeaseLosses	-6232000	USD
CY2020Q1	us-gaap	Provision For Loan And Lease Losses ProvisionForLoanAndLeaseLosses	57953000	USD
CY2021Q1	us-gaap	Interest Income Expense After Provision For Loan Loss InterestIncomeExpenseAfterProvisionForLoanLoss	211980000	USD
CY2020Q1	us-gaap	Interest Income Expense After Provision For Loan Loss InterestIncomeExpenseAfterProvisionForLoanLoss	143112000	USD
CY2021Q1	cbsh	Bank Card Transaction Fees BankCardTransactionFees	37695000	USD
CY2020Q1	cbsh	Bank Card Transaction Fees BankCardTransactionFees	40200000	USD
CY2021Q1	cbsh	Trustfeerevenue Trustfeerevenue	44127000	USD
CY2020Q1	cbsh	Trustfeerevenue Trustfeerevenue	39965000	USD
CY2021Q1	cbsh	Depositfeerevenue Depositfeerevenue	22575000	USD
CY2020Q1	cbsh	Depositfeerevenue Depositfeerevenue	23677000	USD
CY2021Q1	us-gaap	Noninterest Income Other NoninterestIncomeOther	4981000	USD
CY2020Q1	us-gaap	Noninterest Income Other NoninterestIncomeOther	3790000	USD
CY2021Q1	us-gaap	Brokerage Commissions Revenue BrokerageCommissionsRevenue	4081000	USD
CY2020Q1	us-gaap	Brokerage Commissions Revenue BrokerageCommissionsRevenue	4077000	USD
CY2021Q1	cbsh	Loan Fees And Sales LoanFeesAndSales	10184000	USD
CY2020Q1	cbsh	Loan Fees And Sales LoanFeesAndSales	3235000	USD
CY2021Q1	us-gaap	Noninterest Income Other Operating Income NoninterestIncomeOtherOperatingIncome	12402000	USD
CY2020Q1	us-gaap	Noninterest Income Other Operating Income NoninterestIncomeOtherOperatingIncome	8719000	USD
CY2021Q1	us-gaap	Noninterest Income NoninterestIncome	136045000	USD
CY2020Q1	us-gaap	Noninterest Income NoninterestIncome	123663000	USD
CY2021Q1	us-gaap	Gain Loss On Investments GainLossOnInvestments	9853000	USD
CY2020Q1	us-gaap	Gain Loss On Investments GainLossOnInvestments	-13301000	USD
CY2021Q1	us-gaap	Labor And Related Expense LaborAndRelatedExpense	129033000	USD
CY2020Q1	us-gaap	Labor And Related Expense LaborAndRelatedExpense	128937000	USD
CY2021Q1	us-gaap	Occupancy Net OccupancyNet	12021000	USD
CY2020Q1	us-gaap	Occupancy Net OccupancyNet	11748000	USD
CY2021Q1	us-gaap	Equipment Expense EquipmentExpense	4353000	USD
CY2020Q1	us-gaap	Equipment Expense EquipmentExpense	4821000	USD
CY2021Q1	cbsh	Supplies Postage And Communication SuppliesPostageAndCommunication	4125000	USD
CY2020Q1	cbsh	Supplies Postage And Communication SuppliesPostageAndCommunication	4658000	USD
CY2021Q1	us-gaap	Information Technology And Data Processing InformationTechnologyAndDataProcessing	25463000	USD
CY2020Q1	us-gaap	Information Technology And Data Processing InformationTechnologyAndDataProcessing	23555000	USD
CY2021Q1	us-gaap	Marketing Expense MarketingExpense	5158000	USD
CY2020Q1	us-gaap	Marketing Expense MarketingExpense	5979000	USD
CY2021Q1	us-gaap	Other Noninterest Expense OtherNoninterestExpense	12420000	USD
CY2020Q1	us-gaap	Other Noninterest Expense OtherNoninterestExpense	14000000	USD
CY2021Q1	us-gaap	Noninterest Expense NoninterestExpense	192573000	USD
CY2020Q1	us-gaap	Noninterest Expense NoninterestExpense	193698000	USD
CY2021Q1	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	165305000	USD
CY2020Q1	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	59776000	USD
CY2021Q1	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	32076000	USD
CY2020Q1	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	10173000	USD
CY2021Q1	us-gaap	Profit Loss ProfitLoss	133229000	USD
CY2020Q1	us-gaap	Profit Loss ProfitLoss	49603000	USD
CY2021Q1	us-gaap	Net Income Loss Attributable To Noncontrolling Interest NetIncomeLossAttributableToNoncontrollingInterest	2257000	USD
CY2020Q1	us-gaap	Net Income Loss Attributable To Noncontrolling Interest NetIncomeLossAttributableToNoncontrollingInterest	-2254000	USD
CY2021Q1	us-gaap	Net Income Loss NetIncomeLoss	130972000	USD
CY2020Q1	us-gaap	Net Income Loss NetIncomeLoss	51857000	USD
CY2021Q1	us-gaap	Preferred Stock Dividends Income Statement Impact PreferredStockDividendsIncomeStatementImpact	0	USD
CY2020Q1	us-gaap	Preferred Stock Dividends Income Statement Impact PreferredStockDividendsIncomeStatementImpact	2250000	USD
CY2021Q1	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	130972000	USD
CY2020Q1	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	49607000	USD
CY2021Q1	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	1.12
CY2020Q1	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.42
CY2021Q1	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	1.11
CY2020Q1	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.42
CY2021Q1	us-gaap	Profit Loss ProfitLoss	133229000	USD
CY2020Q1	us-gaap	Profit Loss ProfitLoss	49603000	USD
CY2021Q1	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Net Of Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodNetOfTax	-158676000	USD
CY2020Q1	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Net Of Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodNetOfTax	78672000	USD
CY2021Q1	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Adjustment Net Of Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentNetOfTax	-437000	USD
CY2020Q1	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Adjustment Net Of Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentNetOfTax	-356000	USD
CY2021Q1	us-gaap	Other Comprehensive Income Loss Derivatives Qualifying As Hedges Net Of Tax OtherComprehensiveIncomeLossDerivativesQualifyingAsHedgesNetOfTax	-4386000	USD
CY2020Q1	us-gaap	Other Comprehensive Income Loss Derivatives Qualifying As Hedges Net Of Tax OtherComprehensiveIncomeLossDerivativesQualifyingAsHedgesNetOfTax	63664000	USD
CY2021Q1	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	-162625000	USD
CY2020Q1	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	142692000	USD
CY2021Q1	us-gaap	Comprehensive Income Net Of Tax Including Portion Attributable To Noncontrolling Interest ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest	-29396000	USD
CY2020Q1	us-gaap	Comprehensive Income Net Of Tax Including Portion Attributable To Noncontrolling Interest ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest	192295000	USD
CY2021Q1	us-gaap	Comprehensive Income Net Of Tax Attributable To Noncontrolling Interest ComprehensiveIncomeNetOfTaxAttributableToNoncontrollingInterest	2257000	USD
CY2020Q1	us-gaap	Comprehensive Income Net Of Tax Attributable To Noncontrolling Interest ComprehensiveIncomeNetOfTaxAttributableToNoncontrollingInterest	-2254000	USD
CY2021Q1	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	-31653000	USD
CY2020Q1	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	194549000	USD
CY2020Q4	us-gaap	Stockholders Equity Including Portion Attributable To Noncontrolling Interest StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest	3399972000	USD
CY2021Q1	us-gaap	Profit Loss ProfitLoss	133229000	USD
CY2021Q1	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	-162625000	USD
CY2021Q1	us-gaap	Minority Interest Decrease From Distributions To Noncontrolling Interest Holders MinorityInterestDecreaseFromDistributionsToNoncontrollingInterestHolders	387000	USD
CY2021Q1	us-gaap	Treasury Stock Value Acquired Cost Method TreasuryStockValueAcquiredCostMethod	25923000	USD
CY2021Q1	us-gaap	Stock Issued During Period Value Share Based Compensation StockIssuedDuringPeriodValueShareBasedCompensation	-15000	USD
CY2021Q1	us-gaap	Adjustments To Additional Paid In Capital Sharebased Compensation Requisite Service Period Recognition Value AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue	3933000	USD
CY2021Q1	us-gaap	Common Stock Dividends Per Share Cash Paid CommonStockDividendsPerShareCashPaid	0.263
CY2021Q1	us-gaap	Dividends Common Stock Cash DividendsCommonStockCash	30799000	USD
CY2021Q1	us-gaap	Stockholders Equity Including Portion Attributable To Noncontrolling Interest StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest	3317385000	USD
CY2019Q4	us-gaap	Stockholders Equity Including Portion Attributable To Noncontrolling Interest StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest	3138472000	USD
CY2020Q1	us-gaap	Profit Loss ProfitLoss	49603000	USD
CY2020Q1	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	142692000	USD
CY2020Q1	us-gaap	Minority Interest Decrease From Distributions To Noncontrolling Interest Holders MinorityInterestDecreaseFromDistributionsToNoncontrollingInterestHolders	85000	USD
CY2020Q1	us-gaap	Treasury Stock Value Acquired Cost Method TreasuryStockValueAcquiredCostMethod	53145000	USD
CY2020Q1	us-gaap	Stock Issued During Period Value Share Based Compensation StockIssuedDuringPeriodValueShareBasedCompensation	-26000	USD
CY2020Q1	us-gaap	Adjustments To Additional Paid In Capital Sharebased Compensation Requisite Service Period Recognition Value AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue	3729000	USD
CY2020Q1	us-gaap	Common Stock Dividends Per Share Cash Paid CommonStockDividendsPerShareCashPaid	0.257
CY2020Q1	us-gaap	Dividends Common Stock Cash DividendsCommonStockCash	30292000	USD
CY2020Q1	us-gaap	Preferred Stock Dividends Per Share Cash Paid PreferredStockDividendsPerShareCashPaid	0.375
CY2020Q1	us-gaap	Dividends Preferred Stock Cash DividendsPreferredStockCash	2250000	USD
CY2020Q1	us-gaap	Stockholders Equity Including Portion Attributable To Noncontrolling Interest StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest	3252464000	USD
CY2021Q1	us-gaap	Profit Loss ProfitLoss	133229000	USD
CY2020Q1	us-gaap	Profit Loss ProfitLoss	49603000	USD
CY2021Q1	us-gaap	Provision For Loan And Lease Losses ProvisionForLoanAndLeaseLosses	-6232000	USD
CY2020Q1	us-gaap	Provision For Loan And Lease Losses ProvisionForLoanAndLeaseLosses	57953000	USD
CY2021Q1	us-gaap	Depreciation Amortization And Accretion Net DepreciationAmortizationAndAccretionNet	11379000	USD
CY2020Q1	us-gaap	Depreciation Amortization And Accretion Net DepreciationAmortizationAndAccretionNet	10581000	USD
CY2021Q1	us-gaap	Accretion Amortization Of Discounts And Premiums Investments AccretionAmortizationOfDiscountsAndPremiumsInvestments	-22079000	USD
CY2020Q1	us-gaap	Accretion Amortization Of Discounts And Premiums Investments AccretionAmortizationOfDiscountsAndPremiumsInvestments	-10362000	USD
CY2021Q1	us-gaap	Gain Loss On Investments GainLossOnInvestments	9853000	USD
CY2020Q1	us-gaap	Gain Loss On Investments GainLossOnInvestments	-13301000	USD
CY2021Q1	us-gaap	Gain Loss On Sale Of Loans And Leases GainLossOnSaleOfLoansAndLeases	7381000	USD
CY2020Q1	us-gaap	Gain Loss On Sale Of Loans And Leases GainLossOnSaleOfLoansAndLeases	1793000	USD
CY2021Q1	cbsh	Origination Of Loans Held For Sale OriginationOfLoansHeldForSale	172435000	USD
CY2020Q1	cbsh	Origination Of Loans Held For Sale OriginationOfLoansHeldForSale	33351000	USD
CY2021Q1	us-gaap	Proceeds From Sale Of Loans Held For Sale ProceedsFromSaleOfLoansHeldForSale	184155000	USD
CY2020Q1	us-gaap	Proceeds From Sale Of Loans Held For Sale ProceedsFromSaleOfLoansHeldForSale	42221000	USD
CY2021Q1	us-gaap	Increase Decrease In Trading Securities IncreaseDecreaseInTradingSecurities	-4872000	USD
CY2020Q1	us-gaap	Increase Decrease In Trading Securities IncreaseDecreaseInTradingSecurities	16107000	USD
CY2021Q1	us-gaap	Share Based Compensation ShareBasedCompensation	3933000	USD
CY2020Q1	us-gaap	Share Based Compensation ShareBasedCompensation	3729000	USD
CY2021Q1	us-gaap	Increase Decrease In Interest And Dividends Receivable IncreaseDecreaseInInterestAndDividendsReceivable	-444000	USD
CY2021Q1	us-gaap	Real Estate Acquired Through Foreclosure RealEstateAcquiredThroughForeclosure	208000	USD
CY2020Q1	us-gaap	Increase Decrease In Interest And Dividends Receivable IncreaseDecreaseInInterestAndDividendsReceivable	1681000	USD
CY2021Q1	us-gaap	Increase Decrease In Interest Payable Net IncreaseDecreaseInInterestPayableNet	-1804000	USD
CY2020Q1	us-gaap	Increase Decrease In Interest Payable Net IncreaseDecreaseInInterestPayableNet	-2161000	USD
CY2021Q1	us-gaap	Increase Decrease In Accrued Income Taxes Payable IncreaseDecreaseInAccruedIncomeTaxesPayable	28105000	USD
CY2020Q1	us-gaap	Increase Decrease In Accrued Income Taxes Payable IncreaseDecreaseInAccruedIncomeTaxesPayable	7992000	USD
CY2021Q1	us-gaap	Increase Decrease In Other Operating Capital Net IncreaseDecreaseInOtherOperatingCapitalNet	-11178000	USD
CY2020Q1	us-gaap	Increase Decrease In Other Operating Capital Net IncreaseDecreaseInOtherOperatingCapitalNet	60881000	USD
CY2021Q1	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	201669000	USD
CY2020Q1	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	79768000	USD
CY2021Q1	cbsh	Proceedsfromsalesandmaturitiesofavailableforsaledebtequityandothersecurities Proceedsfromsalesandmaturitiesofavailableforsaledebtequityandothersecurities	9292000	USD
CY2020Q1	cbsh	Proceedsfromsalesandmaturitiesofavailableforsaledebtequityandothersecurities Proceedsfromsalesandmaturitiesofavailableforsaledebtequityandothersecurities	2000	USD
CY2021Q1	us-gaap	Proceeds From Maturities Prepayments And Calls Of Available For Sale Securities ProceedsFromMaturitiesPrepaymentsAndCallsOfAvailableForSaleSecurities	938527000	USD
CY2020Q1	us-gaap	Proceeds From Maturities Prepayments And Calls Of Available For Sale Securities ProceedsFromMaturitiesPrepaymentsAndCallsOfAvailableForSaleSecurities	641950000	USD
CY2021Q1	us-gaap	Payments To Acquire Investments PaymentsToAcquireInvestments	1194891000	USD
CY2020Q1	us-gaap	Payments To Acquire Investments PaymentsToAcquireInvestments	569079000	USD
CY2021Q1	us-gaap	Payments For Proceeds From Loans And Leases PaymentsForProceedsFromLoansAndLeases	72497000	USD
CY2021Q1	us-gaap	Interest Receivable InterestReceivable	42900000	USD
CY2020Q1	us-gaap	Payments For Proceeds From Loans And Leases PaymentsForProceedsFromLoansAndLeases	346910000	USD
CY2021Q1	us-gaap	Payments To Acquire Property Plant And Equipment PaymentsToAcquirePropertyPlantAndEquipment	10730000	USD
CY2020Q1	us-gaap	Payments To Acquire Property Plant And Equipment PaymentsToAcquirePropertyPlantAndEquipment	7574000	USD
CY2021Q1	us-gaap	Proceeds From Sale Of Property Plant And Equipment ProceedsFromSaleOfPropertyPlantAndEquipment	2568000	USD
CY2020Q1	us-gaap	Proceeds From Sale Of Property Plant And Equipment ProceedsFromSaleOfPropertyPlantAndEquipment	17000	USD
CY2021Q1	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-327731000	USD
CY2020Q1	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-281594000	USD
CY2021Q1	cbsh	Net Increase Decrease Non Interest Bearing Savings Interest Checking And Money Market Deposits NetIncreaseDecreaseNonInterestBearingSavingsInterestCheckingAndMoneyMarketDeposits	585579000	USD
CY2020Q1	cbsh	Net Increase Decrease Non Interest Bearing Savings Interest Checking And Money Market Deposits NetIncreaseDecreaseNonInterestBearingSavingsInterestCheckingAndMoneyMarketDeposits	181625000	USD
CY2021Q1	us-gaap	Increase Decrease In Time Deposits IncreaseDecreaseInTimeDeposits	-73000000	USD
CY2020Q1	us-gaap	Increase Decrease In Time Deposits IncreaseDecreaseInTimeDeposits	-233664000	USD
CY2021Q1	us-gaap	Increase Decrease In Federal Funds Purchased And Securities Sold Under Agreements To Repurchase Net IncreaseDecreaseInFederalFundsPurchasedAndSecuritiesSoldUnderAgreementsToRepurchaseNet	-160273000	USD
CY2020Q1	us-gaap	Increase Decrease In Federal Funds Purchased And Securities Sold Under Agreements To Repurchase Net IncreaseDecreaseInFederalFundsPurchasedAndSecuritiesSoldUnderAgreementsToRepurchaseNet	-422759000	USD
CY2021Q1	cbsh	Net Increase Decrease In Short Term Borrowings NetIncreaseDecreaseInShortTermBorrowings	2989000	USD
CY2020Q1	cbsh	Net Increase Decrease In Short Term Borrowings NetIncreaseDecreaseInShortTermBorrowings	754043000	USD
CY2021Q1	us-gaap	Payments For Repurchase Of Common Stock PaymentsForRepurchaseOfCommonStock	25923000	USD
CY2020Q1	us-gaap	Payments For Repurchase Of Common Stock PaymentsForRepurchaseOfCommonStock	53145000	USD
CY2021Q1	cbsh	Paymentsforstockvalueissuedundersharebasedcompensationplans Paymentsforstockvalueissuedundersharebasedcompensationplans	15000	USD
CY2020Q1	cbsh	Paymentsforstockvalueissuedundersharebasedcompensationplans Paymentsforstockvalueissuedundersharebasedcompensationplans	26000	USD
CY2021Q1	us-gaap	Payments Of Dividends Common Stock PaymentsOfDividendsCommonStock	30799000	USD
CY2020Q1	us-gaap	Payments Of Dividends Common Stock PaymentsOfDividendsCommonStock	30292000	USD
CY2021Q1	us-gaap	Payments Of Dividends Preferred Stock And Preference Stock PaymentsOfDividendsPreferredStockAndPreferenceStock	0	USD
CY2020Q1	us-gaap	Payments Of Dividends Preferred Stock And Preference Stock PaymentsOfDividendsPreferredStockAndPreferenceStock	2250000	USD
CY2021Q1	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	298558000	USD
CY2020Q1	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	193532000	USD
CY2021Q1	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Excluding Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseExcludingExchangeRateEffect	172496000	USD
CY2020Q1	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Excluding Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseExcludingExchangeRateEffect	-8294000	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
CY2021Q1	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	2380824000	USD
CY2020Q1	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	899514000	USD
CY2021Q1	us-gaap	Income Taxes Paid Net IncomeTaxesPaidNet	2510000	USD
CY2020Q1	us-gaap	Income Taxes Paid Net IncomeTaxesPaidNet	1170000	USD
CY2021Q1	us-gaap	Interest Paid Net InterestPaidNet	5753000	USD
CY2020Q1	us-gaap	Interest Paid Net InterestPaidNet	22581000	USD
CY2021Q1	us-gaap	Transfer To Other Real Estate TransferToOtherRealEstate	115000	USD
CY2020Q1	us-gaap	Transfer To Other Real Estate TransferToOtherRealEstate	57000	USD
CY2021Q1	us-gaap	Restricted Cash And Cash Equivalents RestrictedCashAndCashEquivalents	24500000	USD
CY2020Q1	us-gaap	Restricted Cash And Cash Equivalents RestrictedCashAndCashEquivalents	23800000	USD
CY2021Q1	us-gaap	Loans And Leases Receivable Gross Carrying Amount LoansAndLeasesReceivableGrossCarryingAmount	16392071000	USD
CY2020Q4	us-gaap	Loans And Leases Receivable Gross Carrying Amount LoansAndLeasesReceivableGrossCarryingAmount	16329641000	USD
CY2020Q4	us-gaap	Interest Receivable InterestReceivable	41900000	USD
CY2021Q1	us-gaap	Pledged Financial Instruments Not Separately Reported Loans Receivable Pledged For Federal Home Loan Bank Debt PledgedFinancialInstrumentsNotSeparatelyReportedLoansReceivablePledgedForFederalHomeLoanBankDebt	3600000000	USD
CY2021Q1	us-gaap	Pledged Financial Instruments Not Separately Reported Loans Receivable Pledged As Collateral PledgedFinancialInstrumentsNotSeparatelyReportedLoansReceivablePledgedAsCollateral	1400000000	USD
CY2020Q4	us-gaap	Financing Receivable Allowance For Credit Losses FinancingReceivableAllowanceForCreditLosses	220834000	USD
CY2021Q1	us-gaap	Provision For Loan Losses Expensed ProvisionForLoanLossesExpensed	10355000	USD
CY2021Q1	us-gaap	Financing Receivable Allowance For Credit Losses Write Offs FinancingReceivableAllowanceForCreditLossesWriteOffs	12941000	USD
CY2021Q1	us-gaap	Financing Receivable Allowance For Credit Losses Recovery FinancingReceivableAllowanceForCreditLossesRecovery	2989000	USD
CY2021Q1	us-gaap	Financing Receivable Allowance For Credit Loss Writeoff After Recovery FinancingReceivableAllowanceForCreditLossWriteoffAfterRecovery	9952000	USD
CY2021Q1	us-gaap	Financing Receivable Allowance For Credit Losses FinancingReceivableAllowanceForCreditLosses	200527000	USD
CY2020Q4	us-gaap	Off Balance Sheet Credit Loss Liability OffBalanceSheetCreditLossLiability	38307000	USD
CY2021Q1	us-gaap	Off Balance Sheet Credit Loss Liability Credit Loss Expense Reversal OffBalanceSheetCreditLossLiabilityCreditLossExpenseReversal	4123000	USD
CY2021Q1	us-gaap	Off Balance Sheet Credit Loss Liability OffBalanceSheetCreditLossLiability	42430000	USD
CY2021Q1	cbsh	Financing Receivable Allowance For Credit Loss And Unfunded Lending Commitments Total FinancingReceivableAllowanceForCreditLossAndUnfundedLendingCommitmentsTotal	242957000	USD
CY2020Q1	us-gaap	Financing Receivable Allowance For Credit Losses FinancingReceivableAllowanceForCreditLosses	139643000	USD
CY2020Q1	us-gaap	Provision For Loan Losses Expensed ProvisionForLoanLossesExpensed	-42868000	USD
CY2020Q1	us-gaap	Financing Receivable Allowance For Credit Losses Write Offs FinancingReceivableAllowanceForCreditLossesWriteOffs	14392000	USD
CY2020Q1	us-gaap	Financing Receivable Allowance For Credit Losses Recovery FinancingReceivableAllowanceForCreditLossesRecovery	3534000	USD
CY2020Q1	us-gaap	Financing Receivable Allowance For Credit Loss Writeoff After Recovery FinancingReceivableAllowanceForCreditLossWriteoffAfterRecovery	10858000	USD
CY2020Q1	us-gaap	Financing Receivable Allowance For Credit Losses FinancingReceivableAllowanceForCreditLosses	171653000	USD
CY2020Q1	us-gaap	Off Balance Sheet Credit Loss Liability OffBalanceSheetCreditLossLiability	17165000	USD
CY2020Q1	us-gaap	Off Balance Sheet Credit Loss Liability Credit Loss Expense Reversal OffBalanceSheetCreditLossLiabilityCreditLossExpenseReversal	15085000	USD
CY2020Q1	us-gaap	Off Balance Sheet Credit Loss Liability OffBalanceSheetCreditLossLiability	32250000	USD
CY2020Q1	cbsh	Financing Receivable Allowance For Credit Loss And Unfunded Lending Commitments Total FinancingReceivableAllowanceForCreditLossAndUnfundedLendingCommitmentsTotal	203903000	USD
CY2021Q1	cbsh	Financing Receivable Recorded Investment Currentor Lessthan30days Past Due FinancingReceivableRecordedInvestmentCurrentorLessthan30daysPastDue	16313559000	USD
CY2021Q1	cbsh	Financing Receivable Recorded Investment Thirty To Eighty Nine Days Past Due FinancingReceivableRecordedInvestmentThirtyToEightyNineDaysPastDue	33494000	USD
CY2021Q1	us-gaap	Financing Receivable Recorded Investment90 Days Past Due And Still Accruing FinancingReceivableRecordedInvestment90DaysPastDueAndStillAccruing	21512000	USD
CY2021Q1	us-gaap	Financing Receivable Recorded Investment Nonaccrual Status FinancingReceivableRecordedInvestmentNonaccrualStatus	23506000	USD
CY2021Q1	us-gaap	Loans And Leases Receivable Gross Carrying Amount LoansAndLeasesReceivableGrossCarryingAmount	16392071000	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
CY2021Q1	cbsh	Credit Quality Personal Real Estate Loans Excluded CreditQualityPersonalRealEstateLoansExcluded	188600000	USD
CY2020Q4	cbsh	Credit Quality Personal Real Estate Loans Excluded CreditQualityPersonalRealEstateLoansExcluded	191100000	USD
CY2021Q1	cbsh	Consumer Healthcare Loans Excluded ConsumerHealthcareLoansExcluded	179800000	USD
CY2020Q4	cbsh	Consumer Healthcare Loans Excluded ConsumerHealthcareLoansExcluded	188100000	USD
CY2021Q1	cbsh	Credit Quality Personal Banking Loan Table Percentage Loans Excluded CreditQualityPersonalBankingLoanTablePercentageLoansExcluded	0.07	Rate
CY2021Q1	cbsh	Loans Held For Sale90 Days Past Dueand Still Accruing LoansHeldForSale90DaysPastDueandStillAccruing	0	USD
CY2021Q1	us-gaap	Financing Receivable Modifications Recorded Investment FinancingReceivableModificationsRecordedInvestment	139571000	USD
CY2020Q4	us-gaap	Financing Receivable Modifications Recorded Investment FinancingReceivableModificationsRecordedInvestment	140627000	USD
CY2021Q1	cbsh	Period After Which Loans Are Deemed In Default PeriodAfterWhichLoansAreDeemedInDefault	P90D
CY2021Q1	us-gaap	Financing Receivable Modifications Recorded Investment FinancingReceivableModificationsRecordedInvestment	139571000	USD
CY2021Q1	cbsh	Financing Receivable Troubled Debt Restructurings That Subsequently Defaulted Recorded Investment FinancingReceivableTroubledDebtRestructuringsThatSubsequentlyDefaultedRecordedInvestment	2565000	USD
CY2021Q1	cbsh	Effect On Interest Income Resulting From Modification To Credit Card Loans EffectOnInterestIncomeResultingFromModificationToCreditCardLoans	1000000.0	USD
CY2021Q1	us-gaap	Loans And Leases Receivable Impaired Commitment To Lend LoansAndLeasesReceivableImpairedCommitmentToLend	30700000	USD
CY2021Q1	cbsh	Letters Of Credit To Customers With Restructured Loans LettersOfCreditToCustomersWithRestructuredLoans	27700000	USD
CY2021Q1	us-gaap	Mortgages Held For Sale Fair Value Disclosure MortgagesHeldForSaleFairValueDisclosure	30500000	USD
CY2021Q1	cbsh	Unpaid Principal Balanceon Personal Real Estate Loans Heldfor Sale UnpaidPrincipalBalanceonPersonalRealEstateLoansHeldforSale	30000000.0	USD
CY2021Q1	cbsh	Hfs Loansonnonaccrualstatus HFSLoansonnonaccrualstatus	0	USD
CY2020Q4	us-gaap	Real Estate Acquired Through Foreclosure RealEstateAcquiredThroughForeclosure	93000	USD
CY2021Q1	us-gaap	Other Foreclosed Assets OtherForeclosedAssets	1800000	USD
CY2020Q4	us-gaap	Other Foreclosed Assets OtherForeclosedAssets	1400000	USD
CY2021Q1	us-gaap	Available For Sale Securities Debt Securities AvailableForSaleSecuritiesDebtSecurities	12528203000	USD
CY2020Q4	us-gaap	Available For Sale Securities Debt Securities AvailableForSaleSecuritiesDebtSecurities	12449264000	USD
CY2021Q1	us-gaap	Trading Securities TradingSecurities	26925000	USD
CY2020Q4	us-gaap	Trading Securities TradingSecurities	35321000	USD
CY2021Q1	us-gaap	Equity Securities Fv Ni EquitySecuritiesFvNi	2931000	USD
CY2020Q4	us-gaap	Equity Securities Fv Ni EquitySecuritiesFvNi	2966000	USD
CY2021Q1	cbsh	Percentage Decrease In Fair Value Below Amortized Cost PercentageDecreaseInFairValueBelowAmortizedCost	0.20
CY2021Q1	cbsh	Fair Value Securities On Impairment Watch List FairValueSecuritiesOnImpairmentWatchList	25600000	USD
CY2021Q1	cbsh	Equtiy Securitieswithout Readily Determinable Fair Values EqutiySecuritieswithoutReadilyDeterminableFairValues	1406000	USD
CY2020Q4	cbsh	Equtiy Securitieswithout Readily Determinable Fair Values EqutiySecuritieswithoutReadilyDeterminableFairValues	1397000	USD
CY2021Q1	us-gaap	Federal Reserve Bank Stock FederalReserveBankStock	34222000	USD
CY2020Q4	us-gaap	Federal Reserve Bank Stock FederalReserveBankStock	34070000	USD
CY2021Q1	us-gaap	Federal Home Loan Bank Stock FederalHomeLoanBankStock	10125000	USD
CY2020Q4	us-gaap	Federal Home Loan Bank Stock FederalHomeLoanBankStock	10307000	USD
CY2021Q1	us-gaap	Equity Method Investments EquityMethodInvestments	17309000	USD
CY2020Q4	us-gaap	Equity Method Investments EquityMethodInvestments	18000000	USD
CY2021Q1	cbsh	Private Equity Investments PrivateEquityInvestments	94257000	USD
CY2020Q4	cbsh	Private Equity Investments PrivateEquityInvestments	94368000	USD
CY2021Q1	cbsh	Total Investment Securities TotalInvestmentSecurities	12715378000	USD
CY2020Q4	cbsh	Total Investment Securities TotalInvestmentSecurities	12645693000	USD
CY2021Q1	us-gaap	Interest Receivable Current InterestReceivableCurrent	39800000	USD
CY2020Q4	us-gaap	Interest Receivable Current InterestReceivableCurrent	41500000	USD
CY2021Q1	us-gaap	Available For Sale Debt Securities Amortized Cost Basis AvailableForSaleDebtSecuritiesAmortizedCostBasis	12388041000	USD
CY2021Q1	us-gaap	Available For Sale Securities Debt Securities AvailableForSaleSecuritiesDebtSecurities	12528203000	USD
CY2020Q4	cbsh	Fair Value Securities On Impairment Watch List FairValueSecuritiesOnImpairmentWatchList	31000000.0	USD
CY2021Q1	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position Less Than12 Months DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12Months	5128180000	USD
CY2021Q1	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position Less Than12 Months Accumulated Loss DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss	104024000	USD
CY2021Q1	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position12 Months Or Longer DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLonger	199178000	USD
CY2021Q1	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position12 Months Or Longer Accumulated Loss DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLongerAccumulatedLoss	1402000	USD
CY2021Q1	us-gaap	Debt Securities Available For Sale Unrealized Loss Position DebtSecuritiesAvailableForSaleUnrealizedLossPosition	5327358000	USD
CY2021Q1	us-gaap	Debt Securities Available For Sale Unrealized Loss Position Accumulated Loss DebtSecuritiesAvailableForSaleUnrealizedLossPositionAccumulatedLoss	105426000	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
CY2021Q1	us-gaap	Debt Securities Available For Sale Unrealized Loss Position DebtSecuritiesAvailableForSaleUnrealizedLossPosition	5300000000	USD
CY2020Q4	us-gaap	Debt Securities Available For Sale Unrealized Loss Position DebtSecuritiesAvailableForSaleUnrealizedLossPosition	948200000	USD
CY2021Q1	us-gaap	Debt Securities Available For Sale Unrealized Loss Position Accumulated Loss DebtSecuritiesAvailableForSaleUnrealizedLossPositionAccumulatedLoss	105400000	USD
CY2021Q1	cbsh	Af Ssecuritiesinlosspositionatperiodendchangeinunrealizedloss AFSsecuritiesinlosspositionatperiodendchangeinunrealizedloss	99100000	USD
CY2021Q1	us-gaap	Available For Sale Debt Securities Amortized Cost Basis AvailableForSaleDebtSecuritiesAmortizedCostBasis	12388041000	USD
CY2021Q1	cbsh	Available For Sale Securities Gross Unreailzed Gainat Period End AvailableForSaleSecuritiesGrossUnreailzedGainatPeriodEnd	245588000	USD
CY2021Q1	cbsh	Available For Sale Securities Gross Unrealized Lossat Period End AvailableForSaleSecuritiesGrossUnrealizedLossatPeriodEnd	105426000	USD
CY2021Q1	us-gaap	Debt Securities Available For Sale Allowance For Credit Loss DebtSecuritiesAvailableForSaleAllowanceForCreditLoss	0	USD
CY2021Q1	us-gaap	Available For Sale Securities Debt Securities AvailableForSaleSecuritiesDebtSecurities	12528203000	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
CY2021Q1	cbsh	Proceedsfromsaleofequitysecurities Proceedsfromsaleofequitysecurities	0	USD
CY2020Q1	cbsh	Proceedsfromsaleofequitysecurities Proceedsfromsaleofequitysecurities	2000	USD
CY2021Q1	cbsh	Proceeds From Sale Of Other Securities ProceedsFromSaleOfOtherSecurities	9292000	USD
CY2020Q1	cbsh	Proceeds From Sale Of Other Securities ProceedsFromSaleOfOtherSecurities	0	USD
CY2021Q1	cbsh	Proceedsfromsalesandmaturitiesofavailableforsaledebtequityandothersecurities Proceedsfromsalesandmaturitiesofavailableforsaledebtequityandothersecurities	9292000	USD
CY2020Q1	cbsh	Proceedsfromsalesandmaturitiesofavailableforsaledebtequityandothersecurities Proceedsfromsalesandmaturitiesofavailableforsaledebtequityandothersecurities	2000	USD
CY2021Q1	us-gaap	Gain Loss On Investments GainLossOnInvestments	9853000	USD
CY2020Q1	us-gaap	Gain Loss On Investments GainLossOnInvestments	-13301000	USD
CY2021Q1	cbsh	Investment Securities Pledged At Fair Value InvestmentSecuritiesPledgedAtFairValue	4700000000	USD
CY2020Q4	cbsh	Investment Securities Pledged At Fair Value InvestmentSecuritiesPledgedAtFairValue	4800000000	USD
CY2021Q1	us-gaap	Financial Instruments Owned And Pledged As Collateral Amount Eligible To Be Repledged By Counterparty FinancialInstrumentsOwnedAndPledgedAsCollateralAmountEligibleToBeRepledgedByCounterparty	209100000	USD
CY2021Q1	cbsh	Investments Exceeding Ten Percent Of Stockholders Equity InvestmentsExceedingTenPercentOfStockholdersEquity	0
CY2021Q1	cbsh	Percentage Of Stockholders Equity Of Which No Investment From Single Issuer Exceeds PercentageOfStockholdersEquityOfWhichNoInvestmentFromSingleIssuerExceeds	0.10
CY2021Q1	us-gaap	Finite Lived Intangible Assets Gross FiniteLivedIntangibleAssetsGross	48295000	USD
CY2021Q1	us-gaap	Finite Lived Intangible Assets Accumulated Amortization FiniteLivedIntangibleAssetsAccumulatedAmortization	37749000	USD
CY2021Q1	us-gaap	Valuation Allowances And Reserves Balance ValuationAllowancesAndReservesBalance	1048000	USD
CY2021Q1	us-gaap	Finite Lived Intangible Assets Net FiniteLivedIntangibleAssetsNet	9498000	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
CY2020Q4	us-gaap	Finite Lived Intangible Assets Net FiniteLivedIntangibleAssetsNet	7607000	USD
CY2021Q1	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	951000	USD
CY2020Q1	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	268000	USD
CY2021Q1	us-gaap	Finite Lived Intangible Assets Amortization Expense Next Twelve Months FiniteLivedIntangibleAssetsAmortizationExpenseNextTwelveMonths	2198000	USD
CY2021Q1	us-gaap	Finite Lived Intangible Assets Amortization Expense Year Two FiniteLivedIntangibleAssetsAmortizationExpenseYearTwo	1437000	USD
CY2021Q1	us-gaap	Finite Lived Intangible Assets Amortization Expense Year Three FiniteLivedIntangibleAssetsAmortizationExpenseYearThree	1194000	USD
CY2021Q1	us-gaap	Finite Lived Intangible Assets Amortization Expense Year Four FiniteLivedIntangibleAssetsAmortizationExpenseYearFour	991000	USD
CY2021Q1	us-gaap	Finite Lived Intangible Assets Amortization Expense Year Five FiniteLivedIntangibleAssetsAmortizationExpenseYearFive	817000	USD
CY2020Q4	us-gaap	Goodwill Goodwill	138921000	USD
CY2021Q1	us-gaap	Goodwill Goodwill	138921000	USD
CY2021Q1	us-gaap	Sales Type And Direct Financing Leases Profit Loss SalesTypeAndDirectFinancingLeasesProfitLoss	6121000	USD
CY2020Q1	us-gaap	Sales Type And Direct Financing Leases Profit Loss SalesTypeAndDirectFinancingLeasesProfitLoss	6358000	USD
CY2021Q1	us-gaap	Operating Lease Lease Income OperatingLeaseLeaseIncome	2074000	USD
CY2020Q1	us-gaap	Operating Lease Lease Income OperatingLeaseLeaseIncome	2061000	USD
CY2021Q1	us-gaap	Lease Income LeaseIncome	8195000	USD
CY2020Q1	us-gaap	Lease Income LeaseIncome	8419000	USD
CY2021Q1	us-gaap	Defined Benefit Plan Service Cost DefinedBenefitPlanServiceCost	95000	USD
CY2020Q1	us-gaap	Defined Benefit Plan Service Cost DefinedBenefitPlanServiceCost	101000	USD
CY2021Q1	us-gaap	Defined Benefit Plan Interest Cost DefinedBenefitPlanInterestCost	556000	USD
CY2020Q1	us-gaap	Defined Benefit Plan Interest Cost DefinedBenefitPlanInterestCost	822000	USD
CY2021Q1	us-gaap	Defined Benefit Plan Expected Return On Plan Assets DefinedBenefitPlanExpectedReturnOnPlanAssets	1124000	USD
CY2020Q1	us-gaap	Defined Benefit Plan Expected Return On Plan Assets DefinedBenefitPlanExpectedReturnOnPlanAssets	1297000	USD
CY2021Q1	us-gaap	Defined Benefit Plan Amortization Of Prior Service Cost Credit DefinedBenefitPlanAmortizationOfPriorServiceCostCredit	-68000	USD
CY2020Q1	us-gaap	Defined Benefit Plan Amortization Of Prior Service Cost Credit DefinedBenefitPlanAmortizationOfPriorServiceCostCredit	-68000	USD
CY2021Q1	us-gaap	Defined Benefit Plan Amortization Of Gains Losses DefinedBenefitPlanAmortizationOfGainsLosses	-651000	USD
CY2020Q1	us-gaap	Defined Benefit Plan Amortization Of Gains Losses DefinedBenefitPlanAmortizationOfGainsLosses	-542000	USD
CY2021Q1	us-gaap	Defined Benefit Plan Net Periodic Benefit Cost DefinedBenefitPlanNetPeriodicBenefitCost	110000	USD
CY2020Q1	us-gaap	Defined Benefit Plan Net Periodic Benefit Cost DefinedBenefitPlanNetPeriodicBenefitCost	100000	USD
CY2021Q1	us-gaap	Defined Benefit Plan Contributions By Employer DefinedBenefitPlanContributionsByEmployer	0	USD
CY2021Q1	us-gaap	Antidilutive Securities Excluded From Computation Of Earnings Per Share Amount AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount	52000	shares
CY2020Q1	us-gaap	Antidilutive Securities Excluded From Computation Of Earnings Per Share Amount AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount	241000	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
CY2021Q1	us-gaap	Other Comprehensive Income Loss Before Reclassifications Before Tax OtherComprehensiveIncomeLossBeforeReclassificationsBeforeTax	-211569000	USD
CY2021Q1	us-gaap	Reclassification From Accumulated Other Comprehensive Income Current Period Before Tax ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodBeforeTax	5265000	USD
CY2021Q1	us-gaap	Other Comprehensive Income Loss Before Tax OtherComprehensiveIncomeLossBeforeTax	-216834000	USD
CY2021Q1	us-gaap	Other Comprehensive Income Loss Tax OtherComprehensiveIncomeLossTax	-54209000	USD
CY2021Q1	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	-162625000	USD
CY2021Q1	us-gaap	Accumulated Other Comprehensive Income Loss Net Of Tax AccumulatedOtherComprehensiveIncomeLossNetOfTax	168752000	USD
CY2019Q4	us-gaap	Accumulated Other Comprehensive Income Loss Net Of Tax AccumulatedOtherComprehensiveIncomeLossNetOfTax	110444000	USD
CY2020Q1	us-gaap	Other Comprehensive Income Loss Before Reclassifications Before Tax OtherComprehensiveIncomeLossBeforeReclassificationsBeforeTax	189559000	USD
CY2020Q1	us-gaap	Reclassification From Accumulated Other Comprehensive Income Current Period Before Tax ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodBeforeTax	-696000	USD
CY2020Q1	us-gaap	Other Comprehensive Income Loss Before Tax OtherComprehensiveIncomeLossBeforeTax	190255000	USD
CY2020Q1	us-gaap	Other Comprehensive Income Loss Tax OtherComprehensiveIncomeLossTax	47563000	USD
CY2020Q1	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	142692000	USD
CY2020Q1	us-gaap	Accumulated Other Comprehensive Income Loss Net Of Tax AccumulatedOtherComprehensiveIncomeLossNetOfTax	253136000	USD
CY2021Q1	us-gaap	Number Of Operating Segments NumberOfOperatingSegments	3	Operating_Segments
CY2021Q1	cbsh	Number Of Locations NumberOfLocations	160	Locations
CY2020Q1	us-gaap	Revenues Revenues	0	USD
CY2021Q1	us-gaap	Revenues Revenues	0	USD
CY2021Q1	us-gaap	Revenues Revenues	0	USD
CY2020Q1	us-gaap	Revenues Revenues	0	USD
CY2021Q1	us-gaap	Interest Income Expense Net InterestIncomeExpenseNet	205748000	USD
CY2021Q1	us-gaap	Provision For Loan And Lease Losses ProvisionForLoanAndLeaseLosses	-6232000	USD
CY2021Q1	us-gaap	Noninterest Income NoninterestIncome	136045000	USD
CY2021Q1	us-gaap	Gain Loss On Investments GainLossOnInvestments	9853000	USD
CY2021Q1	us-gaap	Noninterest Expense NoninterestExpense	192573000	USD
CY2021Q1	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	165305000	USD
CY2020Q1	us-gaap	Interest Income Expense Net InterestIncomeExpenseNet	201065000	USD
CY2020Q1	us-gaap	Provision For Loan And Lease Losses ProvisionForLoanAndLeaseLosses	57953000	USD
CY2020Q1	us-gaap	Noninterest Income NoninterestIncome	123663000	USD
CY2020Q1	us-gaap	Gain Loss On Investments GainLossOnInvestments	-13301000	USD
CY2020Q1	us-gaap	Noninterest Expense NoninterestExpense	193698000	USD
CY2020Q1	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	59776000	USD
CY2021Q1	us-gaap	Derivative Notional Amount DerivativeNotionalAmount	2994244000	USD
CY2020Q4	us-gaap	Derivative Notional Amount DerivativeNotionalAmount	3015189000	USD
CY2021Q1	us-gaap	Derivative Assets DerivativeAssets	62787000	USD
CY2020Q4	us-gaap	Derivative Assets DerivativeAssets	89889000	USD
CY2021Q1	us-gaap	Derivative Liabilities DerivativeLiabilities	13512000	USD
CY2020Q4	us-gaap	Derivative Liabilities DerivativeLiabilities	18675000	USD
CY2021Q1	us-gaap	Derivative Asset Fair Value Gross Asset Including Not Subject To Master Netting Arrangement DerivativeAssetFairValueGrossAssetIncludingNotSubjectToMasterNettingArrangement	62787000	USD
CY2021Q1	cbsh	Derivative Asset Amount Offset By Liabiilty DerivativeAssetAmountOffsetByLiabiilty	0	USD
CY2021Q1	us-gaap	Derivative Assets DerivativeAssets	62787000	USD
CY2021Q1	us-gaap	Derivative Liability Fair Value Gross Liability Including Not Subject To Master Netting Arrangement DerivativeLiabilityFairValueGrossLiabilityIncludingNotSubjectToMasterNettingArrangement	13512000	USD
CY2021Q1	cbsh	Derivative Liability Amount Offset By Asset DerivativeLiabilityAmountOffsetByAsset	0	USD
CY2021Q1	us-gaap	Derivative Liabilities DerivativeLiabilities	13512000	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
CY2021Q1	us-gaap	Allocated Share Based Compensation Expense AllocatedShareBasedCompensationExpense	3900000	USD
CY2020Q1	us-gaap	Allocated Share Based Compensation Expense AllocatedShareBasedCompensationExpense	3700000	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
CY2021Q1	cbsh	Nonvested Share Awards Granted In Period NonvestedShareAwardsGrantedInPeriod	197191	shares
CY2021Q1	cbsh	Share Based Compensation Granted Nonvested Share Award Weighted Average Grant Date Fair Value ShareBasedCompensationGrantedNonvestedShareAwardWeightedAverageGrantDateFairValue	71.97
CY2021Q1	cbsh	Nonvested Share Awards Vested In Period NonvestedShareAwardsVestedInPeriod	219705	shares
CY2021Q1	cbsh	Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Nonvested Share Awards Vested In Period Weighted Average Grant Date Fair Value ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsNonvestedShareAwardsVestedInPeriodWeightedAverageGrantDateFairValue	43.20
CY2021Q1	cbsh	Nonvested Share Awards Forfeited In Period NonvestedShareAwardsForfeitedInPeriod	4037	shares
CY2021Q1	cbsh	Share Based Compensation Forfeited Nonvested Share Award Weighted Average Grant Date Fair Value ShareBasedCompensationForfeitedNonvestedShareAwardWeightedAverageGrantDateFairValue	56.66
CY2021Q1	cbsh	Nonvested Share Awards Balances NonvestedShareAwardsBalances	1073315	shares
CY2021Q1	cbsh	Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Nonvested Share Awards Weighted Average Grant Date Unit Fair Value ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsNonvestedShareAwardsWeightedAverageGrantDateUnitFairValue	57.56
CY2021Q1	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
CY2021Q1	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Fair Value Assumptions Expected Dividend Rate ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedDividendRate	0.014
CY2021Q1	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Fair Value Assumptions Expected Volatility Rate ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedVolatilityRate	0.282
CY2021Q1	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Fair Value Assumptions Risk Free Interest Rate ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsRiskFreeInterestRate	0.007
CY2021Q1	us-gaap	Sharebased Compensation Arrangement By Sharebased Payment Award Fair Value Assumptions Expected Term1 SharebasedCompensationArrangementBySharebasedPaymentAwardFairValueAssumptionsExpectedTerm1	P5Y8M12D
CY2020Q4	cbsh	Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Number ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNumber	1005896	shares
CY2020Q4	cbsh	Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Weighted Average Exercise Price ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsWeightedAverageExercisePrice	44.95
CY2021Q1	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Grants In Period ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod	72416	shares
CY2021Q1	cbsh	Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Grants In Period Weighted Average Exercise Price ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriodWeightedAverageExercisePrice	72.91
CY2021Q1	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Forfeited In Period ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeitedInPeriod	738	shares
CY2021Q1	cbsh	Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Forfeited In Period Weighted Average Exercise Price ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeitedInPeriodWeightedAverageExercisePrice	57.04
CY2021Q1	cbsh	Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Expired In Period ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsExpiredInPeriod	36	shares
CY2021Q1	cbsh	Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Expired In Period Weighted Average Exercise Price ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsExpiredInPeriodWeightedAverageExercisePrice	57.17
CY2021Q1	cbsh	Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Exercised In Period ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsExercisedInPeriod	208436	shares
CY2021Q1	cbsh	Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Exercised In Period Weighted Average Exercise Price ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsExercisedInPeriodWeightedAverageExercisePrice	39.48
CY2021Q1	cbsh	Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Number ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNumber	869102	shares
CY2021Q1	cbsh	Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Weighted Average Exercise Price ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsWeightedAverageExercisePrice	48.58
CY2021Q1	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Outstanding Weighted Average Remaining Contractual Terms ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsOutstandingWeightedAverageRemainingContractualTerms	P6Y6M
CY2021Q1	us-gaap	Sharebased Compensation Arrangement By Sharebased Payment Award Equity Instruments Other Than Options Aggregate Intrinsic Value Outstanding SharebasedCompensationArrangementBySharebasedPaymentAwardEquityInstrumentsOtherThanOptionsAggregateIntrinsicValueOutstanding	24362000	USD
CY2021Q1	cbsh	Percentof Revenuenotinscopeof Asc606 PercentofRevenuenotinscopeofASC606	0.60	Rate
CY2021Q1	us-gaap	Noninterest Income NoninterestIncome	136045000	USD
CY2020Q1	us-gaap	Noninterest Income NoninterestIncome	123663000	USD
CY2021Q1	us-gaap	Mortgages Held For Sale Fair Value Disclosure MortgagesHeldForSaleFairValueDisclosure	30505000	USD
CY2021Q1	us-gaap	Financial Instruments Owned Us Government And Agency Obligations At Fair Value FinancialInstrumentsOwnedUSGovernmentAndAgencyObligationsAtFairValue	773590000	USD
CY2021Q1	cbsh	Us Government Sponsored Enterprises Debt Securities USGovernmentSponsoredEnterprisesDebtSecurities	50816000	USD
CY2021Q1	us-gaap	Financial Instruments Owned State And Municipal Government Obligations At Fair Value FinancialInstrumentsOwnedStateAndMunicipalGovernmentObligationsAtFairValue	1980811000	USD
CY2021Q1	cbsh	Financial Instruments Owned Agency Mortgage Backed Securities At Fair Value FinancialInstrumentsOwnedAgencyMortgageBackedSecuritiesAtFairValue	6327450000	USD
CY2021Q1	cbsh	Financial Instruments Owned Non Agency Mortgage Backed Securities At Fair Value FinancialInstrumentsOwnedNonAgencyMortgageBackedSecuritiesAtFairValue	358498000	USD
CY2021Q1	cbsh	Other Asset Backed Securities Disclosure OtherAssetBackedSecuritiesDisclosure	2436885000	USD
CY2021Q1	cbsh	Financial Instruments Owned Other Debt Securities At Fair Value FinancialInstrumentsOwnedOtherDebtSecuritiesAtFairValue	600153000	USD
CY2021Q1	us-gaap	Trading Securities TradingSecurities	26925000	USD
CY2021Q1	us-gaap	Equity Securities Fv Ni EquitySecuritiesFvNi	2931000	USD
CY2021Q1	us-gaap	Financial Instruments Owned Principal Investments At Fair Value FinancialInstrumentsOwnedPrincipalInvestmentsAtFairValue	94257000	USD
CY2021Q1	us-gaap	Derivative Assets DerivativeAssets	62787000	USD
CY2021Q1	us-gaap	Deferred Compensation Plan Assets DeferredCompensationPlanAssets	19848000	USD
CY2021Q1	us-gaap	Assets Fair Value Disclosure AssetsFairValueDisclosure	12765456000	USD
CY2021Q1	us-gaap	Derivative Liabilities DerivativeLiabilities	13512000	USD
CY2021Q1	us-gaap	Deferred Compensation Liability Current And Noncurrent DeferredCompensationLiabilityCurrentAndNoncurrent	19848000	USD
CY2021Q1	us-gaap	Liabilities Fair Value Disclosure LiabilitiesFairValueDisclosure	33360000	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
CY2020Q4	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Value FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue	105077000	USD
CY2021Q1	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Gain Loss Included In Earnings1 FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInEarnings1	-7358000	USD
CY2021Q1	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Gain Loss Included In Other Comprehensive Income Loss FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInOtherComprehensiveIncomeLoss	-1000	USD
CY2021Q1	cbsh	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Discount Accretion FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetDiscountAccretion	3000	USD
CY2021Q1	cbsh	Sales And Repayments Of Private Equity Securities SalesAndRepaymentsOfPrivateEquitySecurities	8476000	USD
CY2021Q1	cbsh	Sale Of Risk Participation Agreement SaleOfRiskParticipationAgreement	98000	USD
CY2021Q1	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Value FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue	103863000	USD
CY2021Q1	cbsh	Change In Unrealized Gains Or Losses Related To Assets Held Level3 Fair Value Measurements ChangeInUnrealizedGainsOrLossesRelatedToAssetsHeldLevel3FairValueMeasurements	10415000	USD
CY2021Q1	cbsh	Gains Losses Included In Oci Attributable To Change In Unrealized Gains Losses Relating To Assets Still Held Total GainsLossesIncludedInOCIAttributableToChangeInUnrealizedGainsLossesRelatingToAssetsStillHeldTotal	-1000	USD
CY2019Q4	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Value FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue	104344000	USD
CY2020Q1	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Gain Loss Included In Earnings1 FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInEarnings1	13494000	USD
CY2020Q1	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Gain Loss Included In Other Comprehensive Income Loss FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInOtherComprehensiveIncomeLoss	-1495000	USD
CY2020Q1	cbsh	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Discount Accretion FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetDiscountAccretion	4000	USD
CY2020Q1	cbsh	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Purchase Of Private Equity Securities FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetPurchaseOfPrivateEquitySecurities	114000	USD
CY2020Q1	cbsh	Sales And Repayments Of Private Equity Securities SalesAndRepaymentsOfPrivateEquitySecurities	69000	USD
CY2020Q1	cbsh	Sale Of Risk Participation Agreement SaleOfRiskParticipationAgreement	440000	USD
CY2020Q1	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Value FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue	88964000	USD
CY2020Q1	cbsh	Change In Unrealized Gains Or Losses Related To Assets Held Level3 Fair Value Measurements ChangeInUnrealizedGainsOrLossesRelatedToAssetsHeldLevel3FairValueMeasurements	-13063000	USD
CY2020Q1	cbsh	Gains Losses Included In Oci Attributable To Change In Unrealized Gains Losses Relating To Assets Still Held Total GainsLossesIncludedInOCIAttributableToChangeInUnrealizedGainsLossesRelatingToAssetsStillHeldTotal	-1495000	USD
CY2021Q1	cbsh	Total Gains Or Losses Included In Earnings Level3 Fair Measurements TotalGainsOrLossesIncludedInEarningsLevel3FairMeasurements	7358000	USD
CY2021Q1	cbsh	Change In Unrealized Gains Or Losses Related To Assets Held Level3 Fair Value Measurements ChangeInUnrealizedGainsOrLossesRelatedToAssetsHeldLevel3FairValueMeasurements	10415000	USD
CY2020Q1	cbsh	Total Gains Or Losses Included In Earnings Level3 Fair Measurements TotalGainsOrLossesIncludedInEarningsLevel3FairMeasurements	-13494000	USD
CY2020Q1	cbsh	Change In Unrealized Gains Or Losses Related To Assets Held Level3 Fair Value Measurements ChangeInUnrealizedGainsOrLossesRelatedToAssetsHeldLevel3FairValueMeasurements	-13063000	USD
CY2021Q1	cbsh	Loans Nonrecurring Basis LoansNonrecurringBasis	11233000	USD
CY2021Q1	cbsh	Loans Nonrecurring Basis Gains Losses LoansNonrecurringBasisGainsLosses	-2926000	USD
CY2021Q1	cbsh	Mortgage Servicing Rights Nonrecurring Basis MortgageServicingRightsNonrecurringBasis	8234000	USD
CY2021Q1	cbsh	Mortgage Servicing Rights Nonrecurring Basis Gains Losses MortgageServicingRightsNonrecurringBasisGainsLosses	1055000	USD
CY2020Q1	cbsh	Loans Nonrecurring Basis LoansNonrecurringBasis	124000	USD
CY2020Q1	cbsh	Loans Nonrecurring Basis Gains Losses LoansNonrecurringBasisGainsLosses	-16000	USD
CY2020Q1	cbsh	Mortgage Servicing Rights Nonrecurring Basis MortgageServicingRightsNonrecurringBasis	6768000	USD
CY2020Q1	cbsh	Mortgage Servicing Rights Nonrecurring Basis Gains Losses MortgageServicingRightsNonrecurringBasisGainsLosses	-1056000	USD
CY2021Q1	cbsh	Fair Value Discounted Cash Flow Valuation Techniques FairValueDiscountedCashFlowValuationTechniques	Discounted cash flow

Files In Submission

Name	View Source	Status
0000022356-21-000033-index-headers.html	Edgar Link	pending
0000022356-21-000033-index.html	Edgar Link	pending
0000022356-21-000033.txt	Edgar Link	pending
0000022356-21-000033-xbrl.zip	Edgar Link	pending
cbsh-20210331.htm	Edgar Link	pending
cbsh-20210331.xsd	Edgar Link	pending
cbsh-20210331_cal.xml	Edgar Link	unprocessable
cbsh-20210331_def.xml	Edgar Link	unprocessable
cbsh-20210331_htm.xml	Edgar Link	completed
cbsh-20210331_lab.xml	Edgar Link	unprocessable
cbsh-20210331_pre.xml	Edgar Link	unprocessable
cbsh3312021ex311.htm	Edgar Link	pending
cbsh3312021ex312.htm	Edgar Link	pending
cbsh3312021ex32.htm	Edgar Link	pending
FilingSummary.xml	Edgar Link	unprocessable
Financial_Report.xlsx	Edgar Link	pending
MetaLinks.json	Edgar Link	pending
R1.htm	Edgar Link	pending
R10.htm	Edgar Link	pending
R11.htm	Edgar Link	pending
R12.htm	Edgar Link	pending
R13.htm	Edgar Link	pending
R14.htm	Edgar Link	pending
R15.htm	Edgar Link	pending
R16.htm	Edgar Link	pending
R17.htm	Edgar Link	pending
R18.htm	Edgar Link	pending
R19.htm	Edgar Link	pending
R2.htm	Edgar Link	pending
R20.htm	Edgar Link	pending
R21.htm	Edgar Link	pending
R22.htm	Edgar Link	pending
R23.htm	Edgar Link	pending
R24.htm	Edgar Link	pending
R25.htm	Edgar Link	pending
R26.htm	Edgar Link	pending
R27.htm	Edgar Link	pending
R28.htm	Edgar Link	pending
R29.htm	Edgar Link	pending
R3.htm	Edgar Link	pending
R30.htm	Edgar Link	pending
R31.htm	Edgar Link	pending
R32.htm	Edgar Link	pending
R33.htm	Edgar Link	pending
R34.htm	Edgar Link	pending
R35.htm	Edgar Link	pending
R36.htm	Edgar Link	pending
R37.htm	Edgar Link	pending
R38.htm	Edgar Link	pending
R39.htm	Edgar Link	pending
R4.htm	Edgar Link	pending
R40.htm	Edgar Link	pending
R41.htm	Edgar Link	pending
R42.htm	Edgar Link	pending
R43.htm	Edgar Link	pending
R44.htm	Edgar Link	pending
R45.htm	Edgar Link	pending
R46.htm	Edgar Link	pending
R47.htm	Edgar Link	pending
R48.htm	Edgar Link	pending
R49.htm	Edgar Link	pending
R5.htm	Edgar Link	pending
R50.htm	Edgar Link	pending
R51.htm	Edgar Link	pending
R52.htm	Edgar Link	pending
R53.htm	Edgar Link	pending
R54.htm	Edgar Link	pending
R55.htm	Edgar Link	pending
R56.htm	Edgar Link	pending
R57.htm	Edgar Link	pending
R58.htm	Edgar Link	pending
R59.htm	Edgar Link	pending
R6.htm	Edgar Link	pending
R60.htm	Edgar Link	pending
R61.htm	Edgar Link	pending
R62.htm	Edgar Link	pending
R63.htm	Edgar Link	pending
R64.htm	Edgar Link	pending
R65.htm	Edgar Link	pending
R66.htm	Edgar Link	pending
R67.htm	Edgar Link	pending
R68.htm	Edgar Link	pending
R69.htm	Edgar Link	pending
R7.htm	Edgar Link	pending
R70.htm	Edgar Link	pending
R71.htm	Edgar Link	pending
R72.htm	Edgar Link	pending
R73.htm	Edgar Link	pending
R74.htm	Edgar Link	pending
R75.htm	Edgar Link	pending
R76.htm	Edgar Link	pending
R77.htm	Edgar Link	pending
R78.htm	Edgar Link	pending
R79.htm	Edgar Link	pending
R8.htm	Edgar Link	pending
R80.htm	Edgar Link	pending
R81.htm	Edgar Link	pending
R82.htm	Edgar Link	pending
R83.htm	Edgar Link	pending
R84.htm	Edgar Link	pending
R85.htm	Edgar Link	pending
R86.htm	Edgar Link	pending
R87.htm	Edgar Link	pending
R88.htm	Edgar Link	pending
R89.htm	Edgar Link	pending
R9.htm	Edgar Link	pending
R90.htm	Edgar Link	pending
R91.htm	Edgar Link	pending
R92.htm	Edgar Link	pending
R93.htm	Edgar Link	pending
R94.htm	Edgar Link	pending
R95.htm	Edgar Link	pending
R96.htm	Edgar Link	pending
report.css	Edgar Link	pending
Show.js	Edgar Link	pending

Create your account

Find Stocks Worth Researching

Deeply Understand Businesses

Value Businesses Intelligently

$CBSH
COMMERCE BANCSHARES INC /MO/ Stock $cbsh

2021 Q2 Form 10-Q Financial Statement

#000002235621000033 Filed on May 06, 2021

Income Statement

Balance Sheet

Cashflow Statement

Facts In Submission

Files In Submission

$CBSH COMMERCE BANCSHARES INC /MO/ Stock $cbsh

2021 Q2 Form 10-Q Financial Statement

#000002235621000033 Filed on May 06, 2021

Income Statement

Balance Sheet

Cashflow Statement

Facts In Submission

Files In Submission

$CBSH
COMMERCE BANCSHARES INC /MO/ Stock $cbsh