cm:Concept: us-gaap:DeferredAirTrafficRevenue
| Deferred Air Traffic Revenue, Current |
| us-gaap:DeferredAirTrafficRevenue |
| Value of revenue deferred or cost to provide future services associated with points or miles outstanding and awards that expect to be redeemed through customer loyalty programs and the value of transportation services sold but as yet used by the passenger. Used to reflect the current portion of the liability (within one year or within the normal operating cycle if longer). |
| cm:Concept |
| Monetary (xbrli:monetaryItemType) |
| As Of (instant) |
| Credit |
| false |
| us-gaap:DeferredAirTrafficRevenue |