cm:Member: us-gaap:CollateralizedMortgageObligationsMember
| Collateralized Mortgage Obligations [Member] |
| us-gaap:CollateralizedMortgageObligationsMember |
| The category includes multiclass, pay-through securitizations collateralized by mortgages secured by assets, such as automobiles and boats, which are generally structured so that the collections of principal and interest due from the underlying debtors are paid to the holders of the CMO. |
| cm:Member |
| [Member] (nonnum:domainItemType) |
| For Period (duration) |
| (no balance type) |
| true |
| us-gaap:CollateralizedMortgageObligationsMember |