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SIGNIFICANT ACCOUNTING POLICIES (Details) - USD ($) $ in Millions	3 Months Ended			9 Months Ended
	Sep. 27, 2026	Sep. 28, 2025	Jun. 29, 2025	Sep. 27, 2026	Sep. 28, 2025	Dec. 31, 2025
Disaggregation of Revenue [Line Items]
Contract liabilities	$ 12,644			$ 12,644		$ 11,440
Remaining performance obligation	292,000			$ 292,000
Increase for backlog	61,600
Amount of contract with customer	$ 52,500
Period One \| Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2026-09-28
Disaggregation of Revenue [Line Items]
Revenue, remaining performance obligation, percentage	23.00%			23.00%
Expected time of satisfaction	12 months			12 months
Period Two \| Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2027-09-27
Disaggregation of Revenue [Line Items]
Revenue, remaining performance obligation, percentage	40.00%			40.00%
Expected time of satisfaction	24 months			24 months
United Launch Alliance
Disaggregation of Revenue [Line Items]
Investment membership interest percent	50.00%			50.00%
Equity method investments	$ 578			$ 578		$ 551
Maximum potential future payments	$ 750			$ 750
United Launch Alliance \| The Boeing Company
Disaggregation of Revenue [Line Items]
Investment membership interest percent	50.00%			50.00%
F-16 Program
Disaggregation of Revenue [Line Items]
Unfavorable profit adjustments				$ 170
C-130 Program \| Aeronautics
Disaggregation of Revenue [Line Items]
Unfavorable profit adjustments				175	$ 105
CH-53K program \| RMS
Disaggregation of Revenue [Line Items]
Favorable profit adjustments				125
Seahawk program \| RMS
Disaggregation of Revenue [Line Items]
Favorable profit adjustments				95
Classified Program \| Aeronautics
Disaggregation of Revenue [Line Items]
Reach-forward loss		$ 950			80
Contract liabilities	$ 394			394
Classified Program \| Aeronautics \| Initial Phase
Disaggregation of Revenue [Line Items]
Reach-forward loss			$ 950
Cumulative losses on development	1,800			1,800
Classified Program \| MFC
Disaggregation of Revenue [Line Items]
Cumulative losses on development	1,500			1,500
Contract liabilities	1,000			1,000
CMHP
Disaggregation of Revenue [Line Items]
Reach-forward loss					570
Additional Losses		$ 570
CMHP \| RMS
Disaggregation of Revenue [Line Items]
Cumulative losses on development	670			670
Contract liabilities	360			360
Contract assets	$ 565			$ 565
TUHP \| RMS
Disaggregation of Revenue [Line Items]
Reach-forward loss					95
Commercial Civil Space Programs \| Space
Disaggregation of Revenue [Line Items]
Reach-forward loss					$ 130