Risk Management - Additional Information (Detail) $ in Billions	Dec. 31, 2017 USD ($)
Debt Instrument [Line Items]
Principal amount of long-term variable rate debt	$ 9.6
Variable Rate Debt [Member]
Debt Instrument [Line Items]
Weighted average effective interest rate on variable rate debt	3.40%
American Airlines, Inc. [Member]
Debt Instrument [Line Items]
Principal amount of long-term variable rate debt	$ 9.6
American Airlines, Inc. [Member] | Variable Rate Debt [Member]
Debt Instrument [Line Items]
Weighted average effective interest rate on variable rate debt	3.40%