Revenue Recognition - Changes in Loyalty Program Liability (Details) - USD ($) $ in Millions	9 Months Ended
	Sep. 30, 2018	Dec. 31, 2017
Movement In Contract With Customer, Liability [Roll Forward]
Beginning balance	$ 12,864
Ending balance	$ 13,599
Inactive period before expiration of mileage credits	18 months
Loyalty program liability [Member]
Movement In Contract With Customer, Liability [Roll Forward]
Beginning balance	$ 8,822
Deferral of revenue	2,302
Recognition of revenue	(2,565)
Ending balance	8,559
Deferred revenue, current	3,242	$ 3,121
American Airlines, Inc. [Member]
Movement In Contract With Customer, Liability [Roll Forward]
Beginning balance	12,864
Ending balance	$ 13,599
Inactive period before expiration of mileage credits	18 months
American Airlines, Inc. [Member] | Loyalty program liability [Member]
Movement In Contract With Customer, Liability [Roll Forward]
Beginning balance	$ 8,822
Deferral of revenue	2,302
Recognition of revenue	(2,565)
Ending balance	8,559
Deferred revenue, current	$ 3,242	$ 3,121