cm:Level2TextBlock: us-gaap:RevenueRecognitionServicesRefundableFeesForServices
| Revenue Recognition, Services, Refundable Fees for Services [Policy Text Block] |
| us-gaap:RevenueRecognitionServicesRefundableFeesForServices |
| Disclosure of accounting policy for revenue recognition for a service contract that includes a customer cancellation or termination clause (that is, an arrangement where fees received by the entity may need to be refunded to the customer). This disclosure generally indicates whether revenue for such an arrangement is deferred until the refund period lapses, or whether revenue, net of estimated refunds, is recognized over the refund period. |
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| Text Block (HTML) (nonnum:textBlockItemType) |
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| us-gaap:RevenueRecognitionServicesRefundableFeesForServices |