Leases - Supplemental Balance Sheet Information (Details) - USD ($) $ in Millions	Dec. 31, 2018	Dec. 31, 2017
Operating leases:
Operating lease ROU assets	$ 9,151	$ 0
Current operating lease liabilities	1,654	0
Noncurrent operating lease liabilities	7,902	0
Total operating lease liabilities	9,556
Finance leases:
Property and equipment, at cost	936
Accumulated amortization	(391)
Property and equipment, net	545
Current obligations of finance leases	81
Finance leases, net of current obligations	613
Total finance lease liabilities	$ 694
Weighted average remaining lease term:
Operating leases	7 years 7 months 6 days
Finance leases	7 years 4 months 24 days
Weighted average discount rate:
Operating leases	4.60%
Finance leases	6.50%
American Airlines, Inc. [Member]
Operating leases:
Operating lease ROU assets	$ 9,094	0
Current operating lease liabilities	1,639	0
Noncurrent operating lease liabilities	7,857	$ 0
Total operating lease liabilities	9,496
Finance leases:
Property and equipment, at cost	936
Accumulated amortization	(391)
Property and equipment, net	545
Current obligations of finance leases	81
Finance leases, net of current obligations	613
Total finance lease liabilities	$ 694
Weighted average remaining lease term:
Operating leases	7 years 7 months 6 days
Finance leases	7 years 4 months 24 days
Weighted average discount rate:
Operating leases	4.60%
Finance leases	6.50%