Goodwill and Intangible Assets - Intangible Assets (Details) - USD ($) $ in Millions		Jul. 04, 2021	Dec. 31, 2020
Intangible Assets [Line Items]
Gross Carrying Amount	[1]	$ 4,121	$ 4,210
Accumulated Amortization		(2,118)	(2,093)
Net Carrying Amount		2,003	2,117
Contract and program intangible assets
Intangible Assets [Line Items]
Gross Carrying Amount	[1],[2]	3,406	3,399
Accumulated Amortization	[2]	(1,699)	(1,600)
Net Carrying Amount	[2]	1,707	1,799
Trade names and trademarks
Intangible Assets [Line Items]
Gross Carrying Amount	[1]	498	516
Accumulated Amortization		(229)	(229)
Net Carrying Amount		269	287
Technology and software
Intangible Assets [Line Items]
Gross Carrying Amount	[1]	131	134
Accumulated Amortization		(107)	(106)
Net Carrying Amount		24	28
Other intangible assets
Intangible Assets [Line Items]
Gross Carrying Amount	[1]	86	161
Accumulated Amortization		(83)	(158)
Net Carrying Amount		$ 3	$ 3

[1] Changes in gross carrying amounts consisted primarily of adjustments for write-offs of fully amortized intangible assets, acquired intangible assets and foreign currency translation.

[2] Consisted of acquired backlog and probable follow-on work and associated customer relationships.