cm:Level3TextBlock: us-gaap:CertainLoansAcquiredInTransferNotAccountedForAsDebtSecuritiesAcquiredDuringPeriodTableTextBlock
| Certain Loans Acquired in Transfer Not Accounted for as Debt Securities Acquired During Period [Table Text Block] |
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| Tabular disclosure of the reconciliation of contractual cash flows to the carrying amount relating to certain loans acquired in a transfer. |
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| For Period (duration) |
| (no balance type) |
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