Debt - Summary of Availability under Revolving Credit Facilities (Details) - Revolving Credit Facility [Member] - Secured Debt [Member]	Sep. 30, 2018 USD ($)
Line of Credit Facility [Line Items]
Line of credit facility, maximum borrowing capacity	$ 2,500,000,000
2013 Credit Facilities [Member]
Line of Credit Facility [Line Items]
Line of credit facility, maximum borrowing capacity	1,200,000,000
2014 Credit Facilities [Member]
Line of Credit Facility [Line Items]
Line of credit facility, maximum borrowing capacity	1,000,000,000
April 2016 Credit Facilities [Member]
Line of Credit Facility [Line Items]
Line of credit facility, maximum borrowing capacity	300,000,000
American Airlines, Inc. [Member]
Line of Credit Facility [Line Items]
Line of credit facility, maximum borrowing capacity	2,500,000,000
American Airlines, Inc. [Member] | 2013 Credit Facilities [Member]
Line of Credit Facility [Line Items]
Line of credit facility, maximum borrowing capacity	1,200,000,000
American Airlines, Inc. [Member] | 2014 Credit Facilities [Member]
Line of Credit Facility [Line Items]
Line of credit facility, maximum borrowing capacity	1,000,000,000
American Airlines, Inc. [Member] | April 2016 Credit Facilities [Member]
Line of Credit Facility [Line Items]
Line of credit facility, maximum borrowing capacity	$ 300,000,000