Business Segment Information - Disaggregation of Revenue (Details) - USD ($) $ in Millions	3 Months Ended
	Apr. 02, 2021	Apr. 03, 2020
Disaggregation of Revenue [Line Items]
Revenue	$ 4,567	$ 4,626
Integrated Mission Systems | Transferred over time
Disaggregation of Revenue [Line Items]
Revenue	1,451	1,370
Integrated Mission Systems | Transferred over time | United States
Disaggregation of Revenue [Line Items]
Revenue	1,033	1,105
Integrated Mission Systems | Transferred over time | International
Disaggregation of Revenue [Line Items]
Revenue	418	265
Integrated Mission Systems | Transferred over time | Fixed-price
Disaggregation of Revenue [Line Items]
Revenue	1,093	1,025
Integrated Mission Systems | Transferred over time | Cost-reimbursable
Disaggregation of Revenue [Line Items]
Revenue	358	345
Integrated Mission Systems | Transferred over time | Prime contractor
Disaggregation of Revenue [Line Items]
Revenue	1,006	949
Integrated Mission Systems | Transferred over time | Subcontractor
Disaggregation of Revenue [Line Items]
Revenue	445	421
Space and Airborne Systems | Transferred over time
Disaggregation of Revenue [Line Items]
Revenue	1,236	1,192
Space and Airborne Systems | Transferred over time | United States
Disaggregation of Revenue [Line Items]
Revenue	1,062	1,003
Space and Airborne Systems | Transferred over time | International
Disaggregation of Revenue [Line Items]
Revenue	174	189
Space and Airborne Systems | Transferred over time | Fixed-price
Disaggregation of Revenue [Line Items]
Revenue	716	670
Space and Airborne Systems | Transferred over time | Cost-reimbursable
Disaggregation of Revenue [Line Items]
Revenue	520	522
Space and Airborne Systems | Transferred over time | Prime contractor
Disaggregation of Revenue [Line Items]
Revenue	683	658
Space and Airborne Systems | Transferred over time | Subcontractor
Disaggregation of Revenue [Line Items]
Revenue	553	534
Communication Systems | Transferred at point in time and over time
Disaggregation of Revenue [Line Items]
Revenue	1,112	1,094
Communication Systems | Transferred at point in time and over time | United States
Disaggregation of Revenue [Line Items]
Revenue	841	834
Communication Systems | Transferred at point in time and over time | International
Disaggregation of Revenue [Line Items]
Revenue	271	260
Communication Systems | Transferred at point in time and over time | Fixed-price
Disaggregation of Revenue [Line Items]
Revenue	946	918
Communication Systems | Transferred at point in time and over time | Cost-reimbursable
Disaggregation of Revenue [Line Items]
Revenue	166	176
Communication Systems | Transferred at point in time and over time | Prime contractor
Disaggregation of Revenue [Line Items]
Revenue	729	740
Communication Systems | Transferred at point in time and over time | Subcontractor
Disaggregation of Revenue [Line Items]
Revenue	383	354
Aviation Systems | Transferred at point in time and over time
Disaggregation of Revenue [Line Items]
Revenue	814	1,011
Aviation Systems | Transferred at point in time and over time | United States
Disaggregation of Revenue [Line Items]
Revenue	699	749
Aviation Systems | Transferred at point in time and over time | International
Disaggregation of Revenue [Line Items]
Revenue	115	262
Aviation Systems | Transferred at point in time and over time | Fixed-price
Disaggregation of Revenue [Line Items]
Revenue	652	841
Aviation Systems | Transferred at point in time and over time | Cost-reimbursable
Disaggregation of Revenue [Line Items]
Revenue	162	170
Aviation Systems | Transferred at point in time and over time | Prime contractor
Disaggregation of Revenue [Line Items]
Revenue	536	664
Aviation Systems | Transferred at point in time and over time | Subcontractor
Disaggregation of Revenue [Line Items]
Revenue	$ 278	$ 347