Future Minimum Lease Payments for Capital and Operating Leases (Detail) - USD ($) $ in Millions	Dec. 31, 2015	Dec. 31, 2014
Capital Leases
2016	$ 206
2017	162
2018	151
2019	86
2020	66
After 2020	747
Minimum lease payments	1,418
Imputed interest	(556)
Present value of minimum lease payments	862
Current portion	(135)	$ (110)
Long-term obligations under capital leases	727	$ 571
Present value of minimum lease payments	862
Facility and Other Operating Leases
Operating Leases
2016	1,252
2017	1,161
2018	899
2019	809
2020	920
After 2020	6,799
Minimum lease payments	11,840
Aircraft Operating Leases
Operating Leases
2016	1,317
2017	1,317
2018	1,100
2019	918
2020	708
After 2020	2,660
Minimum lease payments	$ 8,020