Customer Financing (Carrying Values Related to Major Aircraft Concentrations) (Details) - USD ($) $ in Millions	Jun. 30, 2018	Dec. 31, 2017
Customer Financing [Line Items]
Customer financing carrying value	$ 3,120	$ 3,077
Operating leases	1,077	691
B-717 [Member]
Customer Financing [Line Items]
Customer financing carrying value	998	1,081
Operating leases	238	269
B747-8 [Member]
Customer Financing [Line Items]
Customer financing carrying value	480	483
Operating leases	135	138
B-737 [Member]
Customer Financing [Line Items]
Customer financing carrying value	302	161
Operating leases	271	127
B-757 [Member]
Customer Financing [Line Items]
Customer financing carrying value	209	217
Operating leases	26	27
MD 80 Aircraft [Member]
Customer Financing [Line Items]
Customer financing carrying value	204	231
B747-400 aircraft [Member]
Customer Financing [Line Items]
Customer financing carrying value	154	170
Operating leases	77	88
B-777 [Member]
Customer Financing [Line Items]
Customer financing carrying value	41	14
Operating leases	30
B-767 [Member]
Customer Financing [Line Items]
Customer financing carrying value	$ 15	98
Operating leases		$ 25