cm:Level2TextBlock: us-gaap:RevenueRecognitionServicesManagementFees
| Revenue Recognition, Services, Management Fees [Policy Text Block] |
| us-gaap:RevenueRecognitionServicesManagementFees |
| Disclosure of accounting policy for revenue recognition for management fee income, including those that contain a performance-based incentive fee which are based on a formula. This disclosure also may indicate whether the entity has recorded any revenue that is at risk due to future performance contingencies, the nature of contracts giving rise to the contingencies, and, if material, the amount of any such revenue recorded. |
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| us-gaap:RevenueRecognitionServicesManagementFees |