cm:Concept: us-gaap:SensitivityAnalysisOfFairValueOfInterestsContinuedToBeHeldByTransferorServicingAssetsOrLiabilitiesDescriptionOfObjectivesMethodologyAndLimitations
| Sensitivity Analysis of Fair Value, Transferor's Interests in Transferred Financial Assets, Description of Objectives, Methodology, and Limitations |
| us-gaap:SensitivityAnalysisOfFairValueOfInterestsContinuedToBeHeldByTransferorServicingAssetsOrLiabilitiesDescriptionOfObjectivesMethodologyAndLimitations |
| A description of the objectives, methodology, and limitations of the sensitivity analysis or stress test that shows the hypothetical effect on the fair value of transferor's interests in transferred financial assets (including any servicing assets or servicing liabilities) of two or more unfavorable variations from the expected levels for each key assumption that is reported, independently from any change in another key assumption. |
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| Text/String (xbrli:stringItemType) |
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| us-gaap:SensitivityAnalysisOfFairValueOfInterestsContinuedToBeHeldByTransferorServicingAssetsOrLiabilitiesDescriptionOfObjectivesMethodologyAndLimitations |