cm:Level3TextBlock: us-gaap:BelowMarketLeaseFutureAmortizationIncomeTableTextBlock
| Below Market Lease, Future Amortization Income [Table Text Block] |
| us-gaap:BelowMarketLeaseFutureAmortizationIncomeTableTextBlock |
| Tabular disclosure of the amount of amortization income expected to be recorded in succeeding fiscal years for leases acquired as part of a real property acquisition at below market lease rate with a finite life. |
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| Text Block (HTML) (nonnum:textBlockItemType) |
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| us-gaap:BelowMarketLeaseFutureAmortizationIncomeTableTextBlock |