Quarterly Financial Data - Summarized Financial Data (Detail) - USD ($) $ / shares in Units, shares in Thousands, $ in Millions	3 Months Ended								12 Months Ended
	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Selected Quarterly Financial Information [Line Items]
Operating revenues	$ 10,600	$ 10,878	$ 11,105	$ 9,624	$ 9,789	$ 10,594	$ 10,363	$ 9,435	$ 42,207	$ 40,180	$ 40,990
Operating expenses	9,910	9,646	9,570	9,023	9,022	9,163	8,612	8,100	38,149	34,896	34,786
Operating income	690	1,232	1,535	601	767	1,431	1,751	1,335	4,058	5,284	6,204
Net income	$ 258	$ 624	$ 803	$ 234	$ 289	$ 737	$ 950	$ 700	$ 1,919	$ 2,676	$ 7,610
Earnings per share:
Basic (in dollars per share)	$ 0.54	$ 1.29	$ 1.64	$ 0.46	$ 0.56	$ 1.40	$ 1.69	$ 1.15	$ 3.92	$ 4.85	$ 11.39
Diluted (in dollars per share)	$ 0.54	$ 1.28	$ 1.63	$ 0.46	$ 0.56	$ 1.40	$ 1.68	$ 1.14	$ 3.90	$ 4.81	$ 11.07
Shares used for computation (in thousands):
Basic (in shares)	477,165	484,772	490,818	503,902	514,571	525,415	563,000	606,245	489,164	552,308	668,393
Diluted (in shares)	479,382	486,625	492,965	507,797	518,358	528,510	566,040	611,488	491,692	556,099	687,355
American Airlines, Inc. [Member]
Selected Quarterly Financial Information [Line Items]
Operating revenues	$ 10,597	$ 10,875	$ 11,102	$ 9,621	$ 9,786	$ 10,591	$ 10,360	$ 9,427	$ 42,195	$ 40,163	$ 40,938
Operating expenses	9,921	9,650	9,575	9,017	8,995	9,159	8,603	8,104	38,163	34,859	34,749
Operating income	676	1,225	1,527	604	791	1,432	1,757	1,323	4,032	5,304	6,189
Net income	$ 183	$ 649	$ 827	$ 263	$ 341	$ 758	$ 972	$ 710	$ 1,922	$ 2,781	$ 8,120