Quarterly Financial Data - Additional Information (Details) $ in Millions	3 Months Ended		12 Months Ended
	Dec. 31, 2018 USD ($)	Dec. 31, 2017 USD ($) $ / Employees	Dec. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)	Dec. 31, 2016 USD ($)
Restructuring Cost and Reserve [Line Items]
Operating and nonoperating special items, net	$ 225	$ 1,100
Fleet restructuring expenses	146	58	$ 422	$ 232	$ 177
Merger integration expenses	81	81	268	273	514
Severance costs	37		58	0	0
Mark-to-market net unrealized losses on equity investments	22		104	0	0
Net credit (charge) resulting from mark-to-market adjustments for bankruptcy obligations	37	(20)	76	(27)	(25)
Income tax credit, reversal of valuation allowance			6	3	(7)
Employee tax reform bonus expense		$ 149
Tax reform bonus, amount per employee | $ / Employees		1,000
Impact of Tax Act, charge to reduce deferred tax assets		$ 823	0	823	0
Alternative Minimum Tax Credit Carryforward [Member]
Restructuring Cost and Reserve [Line Items]
Income tax credit, reversal of valuation allowance	22
American Airlines, Inc. [Member]
Restructuring Cost and Reserve [Line Items]
Operating and nonoperating special items, net	220	1,200
Fleet restructuring expenses	146	58	422	232	177
Merger integration expenses	81	81	268	273	514
Severance costs	37		58	0	0
Mark-to-market net unrealized losses on equity investments	22		104	0	0
Net credit (charge) resulting from mark-to-market adjustments for bankruptcy obligations	37	(20)	76	(27)	(25)
Income tax credit, reversal of valuation allowance	$ 22		6	(4)	1
Employee tax reform bonus expense		$ 123
Tax reform bonus, amount per employee | $ / Employees		1,000
Impact of Tax Act, charge to reduce deferred tax assets		$ 924	$ 0	$ 924	$ 0