BUSINESS SEGMENT INFORMATION - Revenues and Income From Continuing Operations by Segment (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2022	Oct. 01, 2021	Sep. 30, 2022	Oct. 01, 2021
Segment Reporting Information [Line Items]
Revenue from product sales and services	$ 4,246	$ 4,229	$ 12,484	$ 13,464
Unallocated Items:
Unallocated corporate department income (expense), net(1)	20	(1)	34	(55)
L3Harris Merger-related transaction, integration and other expenses and losses	(21)	(35)	(72)	(79)
Amortization of acquisition-related intangibles	(151)	(155)	(454)	(475)
Business divestiture-related gains, net	0	27	0	192
Charges for severance and other termination costs	(29)	0	(29)	0
Loss Contingency Accrual, Provision	(31)	0	(31)	0
Impairment of goodwill and other assets	0	0	0	(125)
Gain on sale of asset group	0	0	8	0
Acquisition and other divestiture-related expenses	(10)	(8)	(45)	(64)
FAS/CAS operating adjustment	(22)	(30)	(65)	(90)
Total unallocated expenses	(200)	(142)	(524)	(516)
Non-operating income, net	99	111	313	314
Net interest expense	(70)	(67)	(205)	(198)
(Loss) income from continuing operations before income taxes	(321)	586	740	1,695
Income (loss) from emission reduction projects	11		11
Deferred compensation plans	(10)
Income (loss) from deferred compensation arrangement with individual			(20)
Accrual for value added tax obligation				15
FAS/CAS operating adjustment	22	30	65	90
Pension
Unallocated Items:
Income (loss) from deferred compensation plans				(9)
Service cost	(10)	(16)	(32)	(52)
Non-service FAS pension income	(106)	(101)	(317)	(319)
Pension | Plans Under US Government Contracts
Unallocated Items:
FAS/CAS operating adjustment	(22)	(30)	(65)	(90)
Service cost	(11)	(17)	(34)	(54)
Less: CAS pension cost	(33)	(47)	(99)	(144)
FAS/CAS operating adjustment	22	30	65	90
Non-service FAS pension income	111	104	332	329
Net FAS/CAS pension adjustment	133	134	397	419
Operating segments
(Loss) Income from Continuing Operations before Income Taxes
Segment Operating (Loss) Income:	(150)	684	1,156	2,095
Operating segments | Integrated Mission Systems
Segment Reporting Information [Line Items]
Revenue from product sales and services	1,710	1,649	5,104	5,192
(Loss) Income from Continuing Operations before Income Taxes
Segment Operating (Loss) Income:	(225)	232	247	608
Operating segments | Space & Airborne Systems
Segment Reporting Information [Line Items]
Revenue from product sales and services	1,502	1,494	4,450	4,464
(Loss) Income from Continuing Operations before Income Taxes
Segment Operating (Loss) Income:	172	187	539	583
Operating segments | Communication Systems
Segment Reporting Information [Line Items]
Revenue from product sales and services	1,068	1,030	3,024	3,269
(Loss) Income from Continuing Operations before Income Taxes
Segment Operating (Loss) Income:	(97)	258	370	804
Other non-reportable businesses
Segment Reporting Information [Line Items]
Revenue from product sales and services	0	95	0	661
(Loss) Income from Continuing Operations before Income Taxes
Segment Operating (Loss) Income:	0	7	0	100
Corporate
Segment Reporting Information [Line Items]
Revenue from product sales and services	$ (34)	$ (39)	$ (94)	$ (122)