| Standard label: | Deferred Tax Assets, Frequent Flier Liability |
| Name: | us-gaap:DeferredTaxAssetsFrequentFlierLiability |
| Documentation: | Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from frequent flier obligations. |
| Object type: | cm:Concept |
| Data type: | Monetary (xbrli:monetaryItemType) |
| Period type: | As Of (instant) |
| Balance type: | Debit |
| Abstract: | false |
| Workiva Wdesk Taxonomy Analyzer: | us-gaap:DeferredTaxAssetsFrequentFlierLiability |
| Label | Role | Language |
| Deferred Tax Assets, Frequent Flier Liability | http://www.xbrl.org/2003/role/label | en-US |
| Reference | Role | Topic |
| Part Of Roll Up: |
| us-gaap:DeferredTaxAssetsGross |