Debt - EETCs (Details) - American Airlines, Inc. - Enhanced Equipment Trust Certificates (EETC) $ in Millions	12 Months Ended
	Dec. 31, 2020 USD ($) aircraft	Dec. 31, 2019 USD ($)	Aug. 31, 2019 USD ($) aircraft
Debt Instrument [Line Items]
Repayments of long-term debt		$ 608
Enhanced Equipment Trust Certificates 2019-1
Debt Instrument [Line Items]
Aggregate principal issued			$ 1,100
Number of aircraft financed by debt issuance | aircraft			35
Repayments of long-term debt	$ 293	$ 804
Number of aircrafts financed through repurchased debt | aircraft	7		28