Customer Financing (Carrying Values Related to Major Aircraft Concentrations) (Details) - USD ($) $ in Millions	Sep. 30, 2018	Dec. 31, 2017
Customer Financing [Line Items]
Customer financing carrying value	$ 3,225	$ 3,077
Operating leases	1,085	691
B-717 [Member]
Customer Financing [Line Items]
Customer financing carrying value	963	1,081
Operating leases	226	269
B747-8 [Member]
Customer Financing [Line Items]
Customer financing carrying value	478	483
Operating leases	134	138
B-737 [Member]
Customer Financing [Line Items]
Customer financing carrying value	330	161
Operating leases	267	127
MD 80 Aircraft [Member]
Customer Financing [Line Items]
Customer financing carrying value	207	231
B-757 [Member]
Customer Financing [Line Items]
Customer financing carrying value	204	217
Operating leases	25	27
B747-400 aircraft [Member]
Customer Financing [Line Items]
Customer financing carrying value	131	170
Operating leases	56	88
B-787 [Member]
Customer Financing [Line Items]
Customer financing carrying value	115
B-777 [Member]
Customer Financing [Line Items]
Customer financing carrying value	83	14
Operating leases	72
B-767 [Member]
Customer Financing [Line Items]
Customer financing carrying value		98
Operating leases		$ 25