cm:Concept: us-gaap:BelowMarketLeaseAmortizationIncomeNextRollingTwelveMonths
| Below Market Lease, Amortization Income, Next Rolling Twelve Months |
| us-gaap:BelowMarketLeaseAmortizationIncomeNextRollingTwelveMonths |
| Amount of amortization income for leases with a finite life acquired as part of a real property acquisition at below market lease rate expected to be recognized in the next 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) |
| Credit |
| false |
| us-gaap:BelowMarketLeaseAmortizationIncomeNextRollingTwelveMonths |