Liabilities, Commitments and Contingencies - Narrative (Details) $ in Millions	3 Months Ended			12 Months Ended
	Mar. 31, 2024 USD ($) aircraft lot	Mar. 31, 2023 USD ($)	Sep. 30, 2018 USD ($) aircraft	Dec. 31, 2023 USD ($)	Dec. 31, 2018 USD ($) aircraft simulator lot	Dec. 31, 2011 aircraft lot tanker
Commitments And Contingencies [Line Items]
Loss contingency, range of possible loss, portion not accrued	$ 971			$ 1,030
Contingent liabilities on outstanding letters of credit agreements and surety bonds	4,480			4,548
Supplier finance program, obligation	2,500			2,900
Increase to Loss from operations	(366)	$ (518)
Number of annual production lot | lot						13
Alaska Airlines 737-9 Accident and 737-9 Grounding
Commitments And Contingencies [Line Items]
Revenue from contract with customer, excluding assessed tax	443
VC-25B
Commitments And Contingencies [Line Items]
Contract value	$ 4,000
Number of commercial aircraft | aircraft	2
Increase to Loss from operations				(482)
KC-46A Tanker
Commitments And Contingencies [Line Items]
Contract value	$ 27,000
Increase to Loss from operations	$ (128)			(309)
Number of generation aerial refueling tanker | tanker						4
Number of aircraft | aircraft	139					179
Number of low rate initial production lot | lot	10
KC-46A Tanker | Capitalized Precontract Costs
Commitments And Contingencies [Line Items]
Capitalized precontract costs	$ 130
KC-46A Tanker | Potential Termination Liabilities
Commitments And Contingencies [Line Items]
Capitalized precontract costs	214
MQ-25
Commitments And Contingencies [Line Items]
Contract value			$ 890
Increase to Loss from operations			$ 291	(231)
Number of aircraft | aircraft			7
Cost-type contract modification, awarded amount	$ 657
Number of additional test aircraft | aircraft	2
T-7A EMD
Commitments And Contingencies [Line Items]
Contract value					$ 860
Number of aircraft | aircraft					5
Number of simulator | simulator					7
Services probable of being exercised, number of aircrafts | aircraft					346
T-7A Production
Commitments And Contingencies [Line Items]
Number of annual production lot | lot					11
T-7A Production | Capitalized Precontract Costs
Commitments And Contingencies [Line Items]
Capitalized precontract costs	$ 235
T-7A Production | Potential Termination Liabilities
Commitments And Contingencies [Line Items]
Capitalized precontract costs	305
Commercial Crew
Commitments And Contingencies [Line Items]
Increase to Loss from operations				(288)
Commercial Crew | Capitalized Precontract Costs
Commitments And Contingencies [Line Items]
Capitalized precontract costs	229
Commercial Crew | Potential Termination Liabilities
Commitments And Contingencies [Line Items]
Capitalized precontract costs	158
T-7A EMD and Production
Commitments And Contingencies [Line Items]
Increase to Loss from operations	$ (94)			(275)
Minimum | Supplier Finance Program, Majority of Amounts Payable
Commitments And Contingencies [Line Items]
Supplier finance program, payment timing, period	30 days
Maximum
Commitments And Contingencies [Line Items]
Supplier finance program, payment timing, period	12 months
Maximum | Supplier Finance Program, Majority of Amounts Payable
Commitments And Contingencies [Line Items]
Supplier finance program, payment timing, period	90 days
Financing Commitment
Commitments And Contingencies [Line Items]
Other commitment	$ 17,008			17,003
Financing Commitment | External Credit Rating, Non Investment Grade
Commitments And Contingencies [Line Items]
Other commitment	13,682
Joint Venture
Commitments And Contingencies [Line Items]
Other commitment	$ 262
Other commitment, period	9 years
Total Contractual Trade-In Commitment | Commercial Aircraft Commitments
Commitments And Contingencies [Line Items]
Other commitment	$ 1,426			1,415
Net Amounts Payable to Customers Related to Probable Contractual Trade-In Commitments | Commercial Aircraft Commitments
Commitments And Contingencies [Line Items]
Other commitment	311			407
Fair Value of Trade in Value of Aircraft | Commercial Aircraft Commitments
Commitments And Contingencies [Line Items]
Other commitment	311			$ 407
2023
Commitments And Contingencies [Line Items]
Changes in estimates	332
Contingent on Customer Negotiations
Commitments And Contingencies [Line Items]
737 MAX customer concessions and other considerations liability	$ 430