Revenue Recognition - Significant Contract Liabilities (Details) - USD ($) $ in Millions	Sep. 30, 2019	Dec. 31, 2018
Disaggregation of Revenue [Line Items]
Contract balances, liability	$ 14,091	$ 12,878
Loyalty program liability [Member]
Disaggregation of Revenue [Line Items]
Contract balances, liability	8,522	8,539
Air traffic liability [Member]
Disaggregation of Revenue [Line Items]
Contract balances, liability	5,569	4,339
American Airlines, Inc. [Member]
Disaggregation of Revenue [Line Items]
Contract balances, liability	14,091	12,878
American Airlines, Inc. [Member] | Loyalty program liability [Member]
Disaggregation of Revenue [Line Items]
Contract balances, liability	8,522	8,539
American Airlines, Inc. [Member] | Air traffic liability [Member]
Disaggregation of Revenue [Line Items]
Contract balances, liability	$ 5,569	$ 4,339