Revenue - Revenue by Contract Type (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jul. 02, 2017	Jul. 03, 2016	Jul. 02, 2017	Jul. 03, 2016
Revenue [Line Items]
Cost-reimbursement	$ 2,038	$ 1,953	$ 4,056	$ 4,018
Revenue	7,675	7,774	15,116	15,250
Aerospace
Revenue [Line Items]
Cost-reimbursement	0	0	0	0
Revenue	2,078	2,284	4,152	4,065
Combat Systems
Revenue [Line Items]
Cost-reimbursement	196	207	403	423
Revenue	1,414	1,297	2,701	2,542
Information Systems and Technology
Revenue [Line Items]
Cost-reimbursement	1,018	994	2,028	2,043
Revenue	2,104	2,215	4,250	4,543
Marine Systems
Revenue [Line Items]
Cost-reimbursement	824	752	1,625	1,552
Revenue	2,079	1,978	4,013	4,100
Fixed-price Contract
Revenue [Line Items]
Revenue	5,265	5,447	10,300	10,510
Fixed-price Contract | Aerospace
Revenue [Line Items]
Revenue	1,913	2,133	3,815	3,774
Fixed-price Contract | Combat Systems
Revenue [Line Items]
Revenue	1,207	1,081	2,280	2,105
Fixed-price Contract | Information Systems and Technology
Revenue [Line Items]
Revenue	892	1,010	1,822	2,087
Fixed-price Contract | Marine Systems
Revenue [Line Items]
Revenue	1,253	1,223	2,383	2,544
Time-and-materials Contract
Revenue [Line Items]
Revenue	372	374	760	722
Time-and-materials Contract | Aerospace
Revenue [Line Items]
Revenue	165	151	337	291
Time-and-materials Contract | Combat Systems
Revenue [Line Items]
Revenue	11	9	18	14
Time-and-materials Contract | Information Systems and Technology
Revenue [Line Items]
Revenue	194	211	400	413
Time-and-materials Contract | Marine Systems
Revenue [Line Items]
Revenue	$ 2	$ 3	$ 5	$ 4