Liabilities, Commitments, and Contingencies (Schedule of 737 MAX Liability) (Details) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Jun. 30, 2019
Loss Contingencies [Line Items]
737 MAX Customer Concessions & Other Considerations Liability	$ 5,537	$ 7,389
B-737 Aircraft [Member]
Loss Contingencies [Line Items]
737 MAX Customer Concessions & Other Considerations Liability	5,537	7,389	$ 6,110
Payments Made to Customers	2,188	1,237
Concessions & Other In-Kind Considerations to Customers	162	133
Accrual for 737 MAX Customer Concessions and Other Considerations Liability	$ 498	$ 2,649