Income Taxes - Additional Disclosures (Detail) - USD ($) $ in Millions	3 Months Ended	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Income Taxes [Line Items]
Increase (decrease) in valuation allowance		$ (7)	$ (7)	$ 4,800
Valuation allowance, Tax Cuts And Jobs Act Of 2017, deferred tax asset, increase		10
Income tax provision (benefit)		$ 1,165	1,623	(2,994)
Income tax expense, effective rate		38.00%
Impact of tax reform on deferred tax assets and liabilities	$ 7	$ 7	0	0
Effect of Tax Cuts and Jobs Act of 2017, amount		(7)	0	0
Alternative Minimum Tax Credit Carryforward [Member]
Income Taxes [Line Items]
Alternative minimum tax credit carryforwards	339	339
Federal [Member]
Income Taxes [Line Items]
Gross NOL carryforwards	10,000	10,000
Federal NOL carryforwards, maximum allowable utilization	9,000	9,000
Federal NOL carryforwards, remaining amount	8,400	8,400
State [Member]
Income Taxes [Line Items]
Gross NOL carryforwards	3,400	3,400
Substantially All Deferred Tax Assets, Including Net Operating Losses [Member]
Income Taxes [Line Items]
Increase (decrease) in valuation allowance				3,000
American Airlines, Inc. [Member]
Income Taxes [Line Items]
Increase (decrease) in valuation allowance		(12)	(1)	5,200
Valuation allowance, Tax Cuts And Jobs Act Of 2017, deferred tax asset, increase		8
Income tax provision (benefit)		$ 1,322	1,662	(3,452)
Income tax expense, effective rate		41.00%
Impact of tax reform on deferred tax assets and liabilities	(93)	$ (93)	0	0
Effect of Tax Cuts and Jobs Act of 2017, amount		93	$ 0	0
American Airlines, Inc. [Member] | Alternative Minimum Tax Credit Carryforward [Member]
Income Taxes [Line Items]
Alternative minimum tax credit carryforwards	452	452
American Airlines, Inc. [Member] | Federal [Member]
Income Taxes [Line Items]
Gross NOL carryforwards	10,600	10,600
Federal NOL carryforwards, maximum allowable utilization	9,500	9,500
Federal NOL carryforwards, remaining amount	8,600	8,600
American Airlines, Inc. [Member] | State [Member]
Income Taxes [Line Items]
Gross NOL carryforwards	$ 3,200	$ 3,200
American Airlines, Inc. [Member] | Substantially All Deferred Tax Assets, Including Net Operating Losses [Member]
Income Taxes [Line Items]
Increase (decrease) in valuation allowance				$ (3,500)