Employee Benefit Plans - Schedule of Amounts Recognized in Consolidated Balance Sheets (Details) - USD ($) $ in Millions	Dec. 31, 2018	Dec. 31, 2017
Defined Benefit Plan Disclosure [Line Items]
Noncurrent liability	$ 6,907	$ 7,497
Pension Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Current liability	7	10
Noncurrent liability	6,318	6,870
Total liabilities	6,325	6,880
Retiree Medical And Other Postretirement Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Current liability	23	89
Noncurrent liability	589	627
Total liabilities	612	716
American Airlines, Inc. [Member]
Defined Benefit Plan Disclosure [Line Items]
Noncurrent liability	6,863	7,452
American Airlines, Inc. [Member] | Pension Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Current liability	7	10
Noncurrent liability	6,274	6,825
Total liabilities	6,281	6,835
American Airlines, Inc. [Member] | Retiree Medical And Other Postretirement Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Current liability	23	88
Noncurrent liability	589	627
Total liabilities	$ 612	$ 715