Quarterly Financial Data - Summarized Financial Data (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Millions	3 Months Ended								12 Months Ended
	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Selected Quarterly Financial Information [Line Items]
Operating revenues	$ 10,938	$ 11,559	$ 11,643	$ 10,401	$ 10,611	$ 10,965	$ 11,227	$ 9,820	$ 44,541	$ 42,622	$ 40,142
Operating expenses	10,367	10,874	10,639	10,005	9,973	9,709	9,628	9,083	41,885	38,391	35,082
Operating income	571	685	1,004	396	638	1,256	1,599	737	2,656	4,231	5,060
Net income	$ 325	$ 372	$ 556	$ 159	$ (583)	$ 661	$ 864	$ 340	$ 1,412	$ 1,282	$ 2,584
Earnings per share:
Basic (in dollars per share)	$ 0.71	$ 0.81	$ 1.20	$ 0.34	$ (1.22)	$ 1.36	$ 1.76	$ 0.67	$ 3.04	$ 2.62	$ 4.68
Diluted (in dollars per share)	$ 0.70	$ 0.81	$ 1.20	$ 0.34	$ (1.22)	$ 1.36	$ 1.75	$ 0.67	$ 3.03	$ 2.61	$ 4.65
Shares used for computation:
Basic (in shares)	460,589	460,526	463,533	472,297	477,165	484,772	490,818	503,902	464,236	489,164	552,308
Diluted (in shares)	461,915	461,507	464,618	474,598	477,165	486,625	492,965	507,797	465,660	491,692	556,099
American Airlines, Inc. [Member]
Selected Quarterly Financial Information [Line Items]
Operating revenues	$ 10,936	$ 11,556	$ 11,640	$ 10,398	$ 10,607	$ 10,962	$ 11,224	$ 9,817	$ 44,530	$ 42,610	$ 40,125
Operating expenses	10,344	10,850	10,626	9,986	9,982	9,713	9,633	9,077	41,807	38,405	35,045
Operating income	592	706	1,014	412	625	1,249	1,591	740	2,723	4,205	5,080
Net income	$ 407	$ 433	$ 609	$ 209	$ (658)	$ 686	$ 888	$ 369	$ 1,658	$ 1,285	$ 2,689