Commitments and Contingencies (Narrative) (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended		12 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020	Dec. 31, 2020	Dec. 31, 2019
Commitments And Contingencies [Line Items]
737 MAX customer concessions and other considerations liability	$ 4,000		$ 4,000
Loss Contingency, Range of Possible Loss, Portion Not Accrued	1,055		1,055		$ 1,095
Letters of Credit Outstanding, Amount	3,917		3,917		4,238
Lower Customer Delivery Payments
Commitments And Contingencies [Line Items]
737 MAX customer concessions and other considerations liability	1,500		1,500
Cash Payments To Customers
Commitments And Contingencies [Line Items]
737 MAX customer concessions and other considerations liability	800		800
Customer Concessions
Commitments And Contingencies [Line Items]
737 MAX customer concessions and other considerations liability	200		200
Contingent On Customer Negotiations
Commitments And Contingencies [Line Items]
737 MAX customer concessions and other considerations liability	1,500		1,500
Within Current fiscal Year [Member]
Commitments And Contingencies [Line Items]
737 MAX customer concessions and other considerations liability	300		300
Within Next fiscal Year [Member]
Commitments And Contingencies [Line Items]
Abnormal Production cost.			5,000
737 MAX customer concessions and other considerations liability	500		500
Financing Commitment
Commitments And Contingencies [Line Items]
Other Commitment	13,475		13,475		11,512
Joint venture
Commitments And Contingencies [Line Items]
Other Commitment	243		243
Total Contractual Trade-In Commitment | Commercial Aircraft Commitments
Commitments And Contingencies [Line Items]
Other Commitment	623		623		950
Net Amounts Payable to Customers Related to Probable Contractual Trade-In Commitments | Commercial Aircraft Commitments
Commitments And Contingencies [Line Items]
Other Commitment	335		335		599
Fair Value of Trade In Value of Aircraft | Commercial Aircraft Commitments
Commitments And Contingencies [Line Items]
Other Commitment	335		335		580
KC-46A Tanker
Commitments And Contingencies [Line Items]
Contract Value	19,000		19,000
KC-46A Tanker | Capitalized Precontract Costs
Commitments And Contingencies [Line Items]
Loss Contingency, Estimate of Possible Loss	254		254
KC-46A Tanker | Potential Termination Liabilities
Commitments And Contingencies [Line Items]
Loss Contingency, Estimate of Possible Loss	280		280
B-737
Commitments And Contingencies [Line Items]
Abnormal Production cost.	515		1,083		2,567
737 MAX customer concessions and other considerations liability	3,964	$ 6,664	3,964	$ 6,664	$ 5,537	$ 7,389
737 MAX Storage, Pilot Training and Software Updates [Member]
Commitments And Contingencies [Line Items]
Additional expenses as a result of the 737 MAX grounding	$ 50	$ 60	$ 103	$ 121