cm:Level1TextBlock: us-gaap:LoansNotesTradeAndOtherReceivablesDisclosureTextBlock
| Loans, Notes, Trade and Other Receivables Disclosure [Text Block] |
| us-gaap:LoansNotesTradeAndOtherReceivablesDisclosureTextBlock |
| The entire disclosure for claims held for amounts due a entity, excluding financing receivables. Examples include, but are not limited to, trade accounts receivables, notes receivables, loans receivables. Includes disclosure for allowance for credit losses. |
| cm:Level1TextBlock |
| Text Block (HTML) (nonnum:textBlockItemType) |
| For Period (duration) |
| (no balance type) |
| false |
| us-gaap:LoansNotesTradeAndOtherReceivablesDisclosureTextBlock |
| LoansAndLeasesReceivableDisclosure |