cm:Level2TextBlock: us-gaap:RevenueRecognitionCustomerAcquisitions
| Revenue Recognition, Customer Acquisitions [Policy Text Block] |
| us-gaap:RevenueRecognitionCustomerAcquisitions |
| Disclosure of accounting policy for incremental direct costs incurred related to the acquisition or origination of a customer contract in a transaction that results in revenue deferral (that is, whether such costs are expensed as incurred or deferred and charged to expense in proportion to the revenue recognized.) Also describes the entity's policy for determining which costs are capitalized as contract acquisition or origination costs. |
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| us-gaap:RevenueRecognitionCustomerAcquisitions |