cm:Concept: us-gaap:BelowMarketLeaseAmortizationIncomeNextTwelveMonths
| Below Market Lease, Amortization Income, Next Twelve Months |
| us-gaap:BelowMarketLeaseAmortizationIncomeNextTwelveMonths |
| 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 during the next fiscal year following the latest fiscal year. Excludes 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:BelowMarketLeaseAmortizationIncomeNextTwelveMonths |