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Acquisitions, Divestitures, Goodwill and Intangible Assets (Narrative) (Details) $ in Millions		3 Months Ended			9 Months Ended
	Sep. 21, 2021 USD ($)	Sep. 30, 2022 USD ($)	Sep. 30, 2022 AUD ($)	Oct. 01, 2021 USD ($)	Sep. 30, 2022 USD ($)	Oct. 01, 2021 USD ($)	Apr. 29, 2022 USD ($)	Dec. 31, 2021 USD ($)	Jan. 01, 2021 USD ($)
Restructuring Cost and Reserve [Line Items]
Goodwill		$ 6,618,000,000			$ 6,618,000,000			$ 6,744,000,000	$ 6,313,000,000
Goodwill impairments					0	$ 0
Amortization expense		57,000,000		$ 63,000,000	173,000,000	$ 173,000,000
Civil
Restructuring Cost and Reserve [Line Items]
Goodwill		$ 2,039,000,000			$ 2,039,000,000			$ 2,097,000,000	$ 2,047,000,000
Reporting unit, percentage of fair value in excess of carrying amount								6.00%
Aviation & Missile Solutions LLC \| Disposal Group, Disposed of by Sale, Not Discontinued Operations
Restructuring Cost and Reserve [Line Items]
Sale price of business disposal							$ 15,000,000
Cobham Aviation Services
Restructuring Cost and Reserve [Line Items]
Purchase consideration			$ 310
Series of Individually Immaterial Business Acquisitions
Restructuring Cost and Reserve [Line Items]
Purchase consideration	$ 36,000,000
Intangible assets	8,000,000
Goodwill	$ 25,000,000