Employee Benefit Plans - Additional Information (Details)	6 Months Ended
	Jun. 30, 2018 USD ($)
Defined Benefit Plan Disclosure [Line Items]
Employer contributions	$ 311,000,000
Supplemental contributions by employer	272,000,000
Minimum contributions by employer	39,000,000
American Airlines, Inc. [Member]
Defined Benefit Plan Disclosure [Line Items]
Employer contributions	311,000,000
Supplemental contributions by employer	272,000,000
Minimum contributions by employer	$ 39,000,000