BUSINESS SEGMENT INFORMATION - Disaggregation of Revenue (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 29, 2023	Sep. 30, 2022	Sep. 29, 2023	Sep. 30, 2022
Disaggregation of Revenue [Line Items]
Revenue from product sales and services	$ 4,915	$ 4,246	$ 14,079	$ 12,484
SAS | United States
Disaggregation of Revenue [Line Items]
Revenue from product sales and services	1,478	1,414	4,407	4,136
SAS | International
Disaggregation of Revenue [Line Items]
Revenue from product sales and services	196	164	614	510
SAS | Fixed-price
Disaggregation of Revenue [Line Items]
Revenue from product sales and services	1,040	939	3,161	2,737
SAS | Cost-reimbursable
Disaggregation of Revenue [Line Items]
Revenue from product sales and services	634	639	1,860	1,909
SAS | Operating segments
Disaggregation of Revenue [Line Items]
Revenue from product sales and services	1,686	1,593	5,056	4,682
SAS | Intersegment
Disaggregation of Revenue [Line Items]
Revenue from product sales and services	12	15	35	36
IMS | United States
Disaggregation of Revenue [Line Items]
Revenue from product sales and services	1,141	1,213	3,679	3,549
IMS | International
Disaggregation of Revenue [Line Items]
Revenue from product sales and services	406	401	1,258	1,297
IMS | Fixed-price
Disaggregation of Revenue [Line Items]
Revenue from product sales and services	1,164	1,246	3,767	3,716
IMS | Cost-reimbursable
Disaggregation of Revenue [Line Items]
Revenue from product sales and services	383	368	1,170	1,130
IMS | Operating segments
Disaggregation of Revenue [Line Items]
Revenue from product sales and services	1,568	1,630	5,003	4,897
IMS | Intersegment
Disaggregation of Revenue [Line Items]
Revenue from product sales and services	21	16	66	51
CS | United States
Disaggregation of Revenue [Line Items]
Revenue from product sales and services	874	706	2,499	1,962
CS | International
Disaggregation of Revenue [Line Items]
Revenue from product sales and services	366	348	1,168	1,029
CS | Fixed-price
Disaggregation of Revenue [Line Items]
Revenue from product sales and services	1,047	899	3,127	2,530
CS | Cost-reimbursable
Disaggregation of Revenue [Line Items]
Revenue from product sales and services	193	155	540	461
CS | Operating segments
Disaggregation of Revenue [Line Items]
Revenue from product sales and services	1,255	1,068	3,707	3,024
CS | Intersegment
Disaggregation of Revenue [Line Items]
Revenue from product sales and services	15	14	40	33
AR | United States
Disaggregation of Revenue [Line Items]
Revenue from product sales and services	443		443
AR | International
Disaggregation of Revenue [Line Items]
Revenue from product sales and services	12		12
AR | Fixed-price
Disaggregation of Revenue [Line Items]
Revenue from product sales and services	272		272
AR | Cost-reimbursable
Disaggregation of Revenue [Line Items]
Revenue from product sales and services	183		183
AR | Operating segments
Disaggregation of Revenue [Line Items]
Revenue from product sales and services	455		455
AR | Intersegment
Disaggregation of Revenue [Line Items]
Revenue from product sales and services	0		0
Prime contractor | SAS
Disaggregation of Revenue [Line Items]
Revenue from product sales and services	1,082	1,013	3,176	2,977
Prime contractor | IMS
Disaggregation of Revenue [Line Items]
Revenue from product sales and services	962	1,089	3,243	3,210
Prime contractor | CS
Disaggregation of Revenue [Line Items]
Revenue from product sales and services	866	690	2,471	2,037
Prime contractor | AR
Disaggregation of Revenue [Line Items]
Revenue from product sales and services	113		113
Subcontractor | SAS
Disaggregation of Revenue [Line Items]
Revenue from product sales and services	592	565	1,845	1,669
Subcontractor | IMS
Disaggregation of Revenue [Line Items]
Revenue from product sales and services	585	525	1,694	1,636
Subcontractor | CS
Disaggregation of Revenue [Line Items]
Revenue from product sales and services	374	$ 364	1,196	$ 954
Subcontractor | AR
Disaggregation of Revenue [Line Items]
Revenue from product sales and services	$ 342		$ 342