XML 52 R42.htm IDEA: XBRL DOCUMENT
v3.26.1

Fair Value Measurements (Tables) | 3 Months Ended
--- | ---
Mar. 31, 2026
Fair Value Measurements [Abstract] |
Summary Of Assets And Liabilities Measured At Fair Value On A Recurring Basis | The table below presents the March 31, 2026 and December 31, 2025 carrying values of assets and liabilities measured at fair value on a recurring basis. There were no transfers among levels during the first three months of 2026 or the year ended December 31, 2025.
|  | Fair Value Measurements Using
(In thousands) | Total Fair Value | Quoted Prices in Active Markets for Identical Assets (Level 1) | Significant Other Observable Inputs (Level 2) | Significant Unobservable Inputs (Level 3)
March 31, 2026 |  |  |  |
Assets: |  |  |  |
Residential mortgage loans held for sale | $ | 1,657 |  | $ | — |  | $ | 1,657 |  | $ | — |
Available for sale debt securities: |  |  |  |
U.S. government and federal agency obligations | 3,147,293 |  | 3,147,293 |  | — |  | — |
Government-sponsored enterprise obligations | 43,985 |  | — |  | 43,985 |  | — |
State and municipal obligations | 654,824 |  | — |  | 653,874 |  | 950 |
Agency mortgage-backed securities | 3,123,669 |  | — |  | 3,123,669 |  | — |
Non-agency mortgage-backed securities | 414,777 |  | — |  | 414,777 |  | — |
Asset-backed securities | 1,093,819 |  | — |  | 1,093,819 |  | — |
Other debt securities | 167,760 |  | — |  | 167,760 |  | — |
Trading debt securities | 44,329 |  | 13,233 |  | 31,096 |  | — |
Equity securities | 46,193 |  | 46,193 |  | — |  | — |
Private equity investments | 183,764 |  | — |  | — |  | 183,764 |
Derivatives * | 58,399 |  | — |  | 58,216 |  | 183 |
Assets held in trust for deferred compensation plan | 22,437 |  | 22,437 |  | — |  | — |
Total assets | 9,002,906 |  | 3,229,156 |  | 5,588,853 |  | 184,897 |
Liabilities: |  |  |  |
Derivatives * | 15,726 |  | — |  | 15,666 |  | 60 |
Liabilities held in trust for deferred compensation plan | 22,437 |  | 22,437 |  | — |  | — |
Total liabilities | $ | 38,163 |  | $ | 22,437 |  | $ | 15,666 |  | $ | 60 |
December 31, 2025 |  |  |  |
Assets: |  |  |  |
Residential mortgage loans held for sale | $ | 4,028 |  | $ | — |  | $ | 4,028 |  | $ | — |
Available for sale debt securities: |  |  |  |
U.S. government and federal agency obligations | 3,279,100 |  | 3,279,100 |  | — |  | — |
Government-sponsored enterprise obligations | 44,712 |  | — |  | 44,712 |  | — |
State and municipal obligations | 664,733 |  | — |  | 663,781 |  | 952 |
Agency mortgage-backed securities | 3,223,105 |  | — |  | 3,223,105 |  | — |
Non-agency mortgage-backed securities | 435,688 |  | — |  | 435,688 |  | — |
Asset-backed securities | 1,262,045 |  | — |  | 1,262,045 |  | — |
Other debt securities | 186,130 |  | — |  | 186,130 |  | — |
Trading debt securities | 40,080 |  | 13,215 |  | 26,865 |  | — |
Equity securities | 47,551 |  | 47,551 |  | — |  | — |
Private equity investments | 184,343 |  | — |  | — |  | 184,343 |
Derivatives * | 51,421 |  | — |  | 51,232 |  | 189 |
Assets held in trust for deferred compensation plan | 23,276 |  | 23,276 |  | — |  | — |
Total assets | 9,446,212 |  | 3,363,142 |  | 5,897,586 |  | 185,484 |
Liabilities: |  |  |  |
Derivatives * | 18,795 |  | — |  | 18,718 |  | 77 |
Liabilities held in trust for deferred compensation plan | 23,276 |  | 23,276 |  | — |  | — |
Total liabilities | $ | 42,071 |  | $ | 23,276 |  | $ | 18,718 |  | $ | 77 |
* The fair value of each class of derivative is shown in Note 12.
Summary Of Changes In Level 3 Assets And Liabilities Measured At Fair Value On A Recurring Basis | The changes in the Company's Level 3 assets and liabilities measured at fair value on a recurring basis are summarized as follows:
| Fair Value Measurements Using Significant Unobservable Inputs (Level 3) |
(In thousands) | State and Municipal Obligations | Private Equity Investments |  | Total |
For the three months ended March 31, 2026 |  |  |  |  |
Balance January 1, 2026 | $ | 952 |  | $ | 184,343 |  |  | $ | 185,295 |  |
Total gains (losses) realized/unrealized: |  |  |  |  |
Included in earnings | — |  | 10,890 |  |  | 10,890 |  |
Included in other comprehensive income * | (3) |  | — |  |  | (3) |  |
Discount accretion | 1 |  | — |  |  | 1 |  |
Purchases of private equity investments | — |  | 5,601 |  |  | 5,601 |  |
Sale/pay down of private equity investments | — |  | (17,088) |  |  | (17,088) |  |
Capitalized interest/dividends | — |  | 18 |  |  | 18 |  |
Balance at March 31, 2026 | $ | 950 |  | $ | 183,764 |  |  | $ | 184,714 |  |
Total gains (losses) for the three months included in earnings attributable to the change in unrealized gains or losses relating to assets still held at March 31, 2026 | $ | — |  | $ | 10,890 |  |  | $ | 10,890 |  |
*Total gains (losses) for the three months included in other comprehensive income attributable to the change in unrealized gains or losses relating to assets still held at March 31, 2026 | $ | (3) |  | $ | — |  |  | $ | (3) |  |
For the three months ended March 31, 2025 |  |  |  |  |
Balance January 1, 2025 | $ | 964 |  | $ | 184,386 |  |  | $ | 185,350 |  |
Total gains (losses) realized/unrealized: |  |  |  |  |
Included in earnings | — |  | (8,525) |  |  | (8,525) |  |
Included in other comprehensive income * | (18) |  | — |  |  | (18) |  |
Discount accretion | 1 |  | — |  |  | 1 |  |
Purchases of private equity investments | — |  | 5,698 |  |  | 5,698 |  |
Sale/pay down of private equity investments | — |  | (5,958) |  |  | (5,958) |  |
Capitalized interest/dividends | — |  | 17 |  |  | 17 |  |
Balance at March 31, 2025 | $ | 947 |  | $ | 175,618 |  |  | $ | 176,565 |  |
Total gains (losses) for the three months included in earnings attributable to the change in unrealized gains or losses relating to assets still held at March 31, 2025 | $ | — |  | $ | (8,525) |  |  | $ | (8,525) |  |
*Total gains (losses) for the three months included in other comprehensive income attributable to the change in unrealized gains or losses relating to assets still held at March 31, 2025 | $ | (18) |  | $ | — |  |  | $ | (18) |  |
* Included in "net unrealized gains (losses) on available for sale debt securities" in the consolidated statements of comprehensive income.
Summary Of Gains And Losses On Level 3 Assets And Liabilities | Gains and losses included in earnings for the Company's Level 3 assets and liabilities in the previous table are reported in the following line items in the consolidated statements of income:
(In thousands) |  |  | Investment Securities Gains (Losses), Net |
For the three months ended March 31, 2026 |  |  |  |
Total gains or losses included in earnings |  |  | $ | 10,890 |  |
Change in unrealized gains or losses relating to assets still held at March 31, 2026 |  |  | $ | 10,890 |  |
For the three months ended March 31, 2025 |  |  |  |
Total gains or losses included in earnings |  |  | $ | (8,525) |  |
Change in unrealized gains or losses relating to assets still held at March 31, 2025 |  |  | $ | (8,525) |  |
Summary Of Quantitative Information About Level 3 Fair Value Measurements | The Company's Level 3 measurements at March 31, 2026, which employ unobservable inputs that are readily quantifiable, pertain to investments in portfolio concerns held by the Company's private equity subsidiaries. Information about these inputs is presented in the table below.
Quantitative Information about Level 3 Fair Value Measurements |  |  |  | Weighted
| Valuation Technique | Unobservable Input | Range |  | Average*
Private equity investments | Market comparable companies | EBITDA multiple | 4.0 | - | 6.0 |  | 5.1
* Unobservable inputs were weighted by the relative fair value of the instruments.
Schedule Of Fair Value Disclosures Measured On Nonrecurring Basis [Table Text Block] | For assets measured at fair value on a nonrecurring basis during the first three months of 2026 and 2025, and still held as of March 31, 2026 and 2025, the following table provides the adjustments to fair value recognized during the respective periods, the level of valuation inputs used to determine each adjustment, and the carrying value of the related individual assets or portfolios at March 31, 2026 and 2025.
|  | Fair Value Measurements Using |
(In thousands) | Fair Value | Quoted Prices in Active Markets for Identical Assets (Level 1) | Significant Other Observable Inputs (Level 2) | Significant Unobservable Inputs (Level 3) | Total Gains (Losses) Recognized During the Three Months Ended March 31
March 31, 2026 |  |  |  |  |
Collateral dependent loans | $ | 9,092 |  | $ | — |  | $ | — |  | $ | 9,092 |  | $ | (3,719) |
March 31, 2025 |  |  |  |  |
Collateral dependent loans | $ | 3,940 |  | $ | — |  | $ | — |  | $ | 3,940 |  | $ | (400) |
Foreclosed assets | 112 |  | — |  | — |  | 112 |  | (55) |

X
- Definition Fair Value Level Three Gains And Losses Disclosure [Table Text Block] + References No definition available. + Details
Name: | cbsh_FairValueLevelThreeGainsAndLossesDisclosureTableTextBlock
Namespace Prefix: | cbsh_
Data Type: | dtr-types:textBlockItemType
Balance Type: | na
Period Type: | duration

X
- Definition Fair Value Level Three Measurement Disclosures [Table Text Block] + References No definition available. + Details
Name: | cbsh_FairValueLevelThreeMeasurementDisclosuresTableTextBlock
Namespace Prefix: | cbsh_
Data Type: | dtr-types:textBlockItemType
Balance Type: | na
Period Type: | duration

X
- Definition Fair Value Measurements [Abstract] + References No definition available. + Details
Name: | cbsh_FairValueMeasurementsAbstract
Namespace Prefix: | cbsh_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Schedule Of Quantitative Information About Level Three Fair Value Measurements, Measured at Fair Value on a Recurring Basis [Table Text Block]. + References No definition available. + Details
Name: | cbsh_ScheduleOfQuantitativeInformationAboutLevelThreeFairValueMeasurementsRecurringBasisTableTextBlock
Namespace Prefix: | cbsh_
Data Type: | dtr-types:textBlockItemType
Balance Type: | na
Period Type: | duration

X
- Definition Tabular disclosure of assets measured at fair value measured on a recurring or nonrecurring basis. Includes, but is not limited to, fair value measurements recorded and the reasons for the measurements, level within the fair value hierarchy in which the fair value measurements are categorized and transfers between levels 1 and 2. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 820 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482106/820-10-50-2 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 820 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (a) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482106/820-10-50-2 + Details
Name: | us-gaap_FairValueAssetsMeasuredOnRecurringAndNonrecurringBasisTableTextBlock
Namespace Prefix: | us-gaap_
Data Type: | dtr-types:textBlockItemType
Balance Type: | na
Period Type: | duration

X
- Definition Tabular disclosure of assets and liabilities, including [financial] instruments measured at fair value that are classified in stockholders' equity, if any, that are measured at fair value on a recurring basis. The disclosures contemplated herein include the fair value measurements at the reporting date by the level within the fair value hierarchy in which the fair value measurements in their entirety fall, segregating fair value measurements using quoted prices in active markets for identical assets (Level 1), significant other observable inputs (Level 2), and significant unobservable inputs (Level 3). + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 820 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482106/820-10-50-2 Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 820 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (a) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482106/820-10-50-2 + Details
Name: | us-gaap_ScheduleOfFairValueAssetsAndLiabilitiesMeasuredOnRecurringBasisTableTextBlock
Namespace Prefix: | us-gaap_
Data Type: | dtr-types:textBlockItemType
Balance Type: | na
Period Type: | duration