Goodwill (Detail) - USD ($)	3 Months Ended		12 Months Ended
	Mar. 29, 2019	Mar. 30, 2018	Dec. 28, 2018	Dec. 29, 2017
Goodwill [Roll Forward]
Beginning balance, Goodwill	$ 4,860,000,000	$ 4,974,000,000	$ 4,974,000,000
Foreign currency translation adjustments	8,000,000		(51,000,000)
Transfers to assets held for sale			(57,000,000)
Goodwill re-allocation	0
Adjustment to goodwill	3,000,000		(6,000,000)
Ending balance, Goodwill	4,871,000,000		4,860,000,000
Goodwill impairments		0
Defense Solutions
Goodwill [Roll Forward]
Beginning balance, Goodwill	2,015,000,000	2,055,000,000	2,055,000,000
Foreign currency translation adjustments	2,000,000		(40,000,000)
Transfers to assets held for sale			0
Goodwill re-allocation	25,000,000
Adjustment to goodwill	3,000,000		0
Ending balance, Goodwill	2,045,000,000		2,015,000,000
Civil
Goodwill [Roll Forward]
Beginning balance, Goodwill	1,924,000,000	1,998,000,000	1,998,000,000
Foreign currency translation adjustments	6,000,000		(11,000,000)
Transfers to assets held for sale			(57,000,000)
Goodwill re-allocation	(25,000,000)
Adjustment to goodwill	0		(6,000,000)
Ending balance, Goodwill	1,905,000,000		1,924,000,000
Accumulated goodwill impairment losses	117,000,000		117,000,000	$ 117,000,000
Health
Goodwill [Roll Forward]
Beginning balance, Goodwill	921,000,000	$ 921,000,000	921,000,000
Foreign currency translation adjustments	0		0
Transfers to assets held for sale			0
Goodwill re-allocation	0
Adjustment to goodwill	0		0
Ending balance, Goodwill	921,000,000		921,000,000
Accumulated goodwill impairment losses	$ 369,000,000		$ 369,000,000	$ 369,000,000