Commitments and Contingencies Commitments and Contingencies (Schedule of 737 Max LIability) (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020	Dec. 31, 2020	Dec. 31, 2019
Commitments And Contingencies [Line Items]
737 MAX customer concessions and other considerations liability	$ 4,400
B-737
Commitments And Contingencies [Line Items]
737 MAX customer concessions and other considerations liability	4,370	$ 6,686	$ 5,537	$ 7,389
Payments made to customers	(1,172)	(671)
Concessions and other in-kind consideration to customers	(25)	(2)
Accrual for 737 MAX customer concessions and other considerations liability	$ 30	$ (30)