Business Segment Information - Disaggregation of Revenue (Details) - USD ($) $ in Millions	3 Months Ended
	Apr. 03, 2020	Mar. 29, 2019
Disaggregation of Revenue [Line Items]
Revenue	$ 4,626	$ 1,728
Integrated Mission Systems | Transferred over time
Disaggregation of Revenue [Line Items]
Revenue	1,370	14
Integrated Mission Systems | Transferred over time | United States
Disaggregation of Revenue [Line Items]
Revenue	1,105	9
Integrated Mission Systems | Transferred over time | International
Disaggregation of Revenue [Line Items]
Revenue	265	5
Integrated Mission Systems | Transferred over time | Fixed-price
Disaggregation of Revenue [Line Items]
Revenue	1,025	14
Integrated Mission Systems | Transferred over time | Cost-reimbursable
Disaggregation of Revenue [Line Items]
Revenue	345	0
Integrated Mission Systems | Transferred over time | Prime contractor
Disaggregation of Revenue [Line Items]
Revenue	949	8
Integrated Mission Systems | Transferred over time | Subcontractor
Disaggregation of Revenue [Line Items]
Revenue	421	6
Space and Airborne Systems | Transferred over time
Disaggregation of Revenue [Line Items]
Revenue	1,192	956
Space and Airborne Systems | Transferred over time | United States
Disaggregation of Revenue [Line Items]
Revenue	1,003	846
Space and Airborne Systems | Transferred over time | International
Disaggregation of Revenue [Line Items]
Revenue	189	110
Space and Airborne Systems | Transferred over time | Fixed-price
Disaggregation of Revenue [Line Items]
Revenue	670	531
Space and Airborne Systems | Transferred over time | Cost-reimbursable
Disaggregation of Revenue [Line Items]
Revenue	522	425
Space and Airborne Systems | Transferred over time | Prime contractor
Disaggregation of Revenue [Line Items]
Revenue	658	572
Space and Airborne Systems | Transferred over time | Subcontractor
Disaggregation of Revenue [Line Items]
Revenue	534	384
Communication Systems | Transferred at point in time and over time
Disaggregation of Revenue [Line Items]
Revenue	1,094	580
Communication Systems | Transferred at point in time and over time | United States
Disaggregation of Revenue [Line Items]
Revenue	834	347
Communication Systems | Transferred at point in time and over time | International
Disaggregation of Revenue [Line Items]
Revenue	260	233
Communication Systems | Transferred at point in time and over time | Fixed-price
Disaggregation of Revenue [Line Items]
Revenue	918
Communication Systems | Transferred at point in time and over time | Cost-reimbursable
Disaggregation of Revenue [Line Items]
Revenue	176
Communication Systems | Transferred at point in time and over time | Prime contractor
Disaggregation of Revenue [Line Items]
Revenue	740
Communication Systems | Transferred at point in time and over time | Subcontractor
Disaggregation of Revenue [Line Items]
Revenue	354
Aviation Systems | Transferred at point in time and over time
Disaggregation of Revenue [Line Items]
Revenue	1,011	144
Aviation Systems | Transferred at point in time and over time | United States
Disaggregation of Revenue [Line Items]
Revenue	749	143
Aviation Systems | Transferred at point in time and over time | International
Disaggregation of Revenue [Line Items]
Revenue	262	1
Aviation Systems | Transferred at point in time and over time | Fixed-price
Disaggregation of Revenue [Line Items]
Revenue	841	122
Aviation Systems | Transferred at point in time and over time | Cost-reimbursable
Disaggregation of Revenue [Line Items]
Revenue	170	22
Aviation Systems | Transferred at point in time and over time | Prime contractor
Disaggregation of Revenue [Line Items]
Revenue	664	140
Aviation Systems | Transferred at point in time and over time | Subcontractor
Disaggregation of Revenue [Line Items]
Revenue	$ 347	$ 4