Inventories (Narrative) (Details) $ in Millions	Mar. 31, 2019 USD ($) aircraft	Dec. 31, 2018 USD ($)
Inventory [Line Items]
Long-term contracts in progress	$ 1,159	$ 2,129
Other Inventory, Gross	8,720	7,685
Airplane Program 787 [Member]
Inventory [Line Items]
Inventory, Work in Process, Gross	27,749	27,852
Amount of Deferred Costs Related to Long-term Contracts	22,029	22,967
Advances on Inventory Purchases	2,379	2,453
Unamortized Tooling	2,532	2,638
Recovered Production Costs Excess Recoverable Under Existing Firm Orders	16,656
Unrecovered Production Costs, Excess Unrecoverable under Existing Firm Orders	7,905
Airplane Program 747 [Member]
Inventory [Line Items]
Unamortized Tooling	105	116
Recovered Production Costs Excess Recoverable Under Existing Firm Orders	$ 100
Unsold Aircraft | aircraft	1
Ula [Member]
Inventory [Line Items]
Long-term contracts in progress	$ 193	227
Capitalized Precontract Costs [Member]
Inventory [Line Items]
Inventory Amount, Unpriced Change Orders for Long-term Contracts or Programs	661	644
Early Issue Sales Consideration [Member]
Inventory [Line Items]
Inventory Amount, Unpriced Change Orders for Long-term Contracts or Programs	$ 2,724	$ 2,844