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Acquisitions, Divestitures, Goodwill and Intangible Assets (Narrative) (Details) - USD ($)			3 Months Ended
	Sep. 21, 2021	May 07, 2021	Apr. 01, 2022	Apr. 02, 2021	Apr. 29, 2022	Dec. 31, 2021	Jan. 01, 2021
Restructuring Cost and Reserve [Line Items]
Goodwill			$ 6,742,000,000			$ 6,744,000,000	$ 6,313,000,000
Goodwill impairments			0	$ 0
Amortization expense			59,000,000	$ 55,000,000
Civil
Restructuring Cost and Reserve [Line Items]
Goodwill			2,090,000,000			$ 2,097,000,000	$ 2,047,000,000
Reporting unit, percentage of fair value in excess of carrying amount						6.00%
Subsequent Event \| Disposal Group, Held-for-sale, Not Discontinued Operations \| Aviation & Missile Solutions LLC
Restructuring Cost and Reserve [Line Items]
Sale price of business disposal					$ 15,000,000
Gibbs & Cox
Restructuring Cost and Reserve [Line Items]
Preliminary purchase consideration		$ 375,000,000
Cash acquired		$ 1,000,000
Goodwill			276,000,000
Revenue			$ 27,000,000
Series of Individually Immaterial Business Acquisitions
Restructuring Cost and Reserve [Line Items]
Preliminary purchase consideration	$ 36,000,000
Goodwill	25,000,000
Intangible assets	$ 8,000,000