cm:Concept: us-gaap:LifeSettlementContractsInvestmentMethodCarryingAmountMaturingAfterRollingYearFive
| Life Settlement Contracts, Investment Method, Carrying Amount, Maturing after Rolling Year Five |
| us-gaap:LifeSettlementContractsInvestmentMethodCarryingAmountMaturingAfterRollingYearFive |
| Amount of life settlement contracts accounted for under the investment method maturing after the fifth rolling twelve months following the latest balance sheet. For interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date. |
| cm:Concept |
| Monetary (xbrli:monetaryItemType) |
| As Of (instant) |
| Debit |
| false |
| us-gaap:LifeSettlementContractsInvestmentMethodCarryingAmountMaturingAfterRollingYearFive |