cm:Level2TextBlock: us-gaap:TransfersAndServicingOfFinancialAssetsTransfersOfFinancialAssetsPolicy
| Transfers and Servicing of Financial Assets, Transfers of Financial Assets, Policy [Policy Text Block] |
| us-gaap:TransfersAndServicingOfFinancialAssetsTransfersOfFinancialAssetsPolicy |
| Disclosure of accounting policy for transfers of financial assets, including securitization transactions. The disclosure is generally expected to include how the entity determines whether a transaction is accounted for as a sale or financing, and the initial and subsequent accounting for such a transaction. The disclosure also may address how interests that are obtained and sold, or those that continue to be held, in such transactions are measured and accounted for, and the methodology and significant assumptions used to value such interests, and the gains or losses resulting from the sale. |
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| us-gaap:TransfersAndServicingOfFinancialAssetsTransfersOfFinancialAssetsPolicy |