OTHER - Changes in Estimates (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended			9 Months Ended
	Sep. 26, 2021	Jun. 27, 2021	Sep. 27, 2020	Sep. 26, 2021	Sep. 27, 2020
Change in Accounting Estimate [Line Items]
Performance obligation satisfied in previous period	$ 616		$ 487	$ 1,600	$ 1,500
Classified Fixed-Price Incentive Fee Contract
Change in Accounting Estimate [Line Items]
Performance growth costs per share, after tax (in dollars per share)	$ 0.12
Classified Fixed-Price Incentive Fee Contract | Aeronautics
Change in Accounting Estimate [Line Items]
Performance growth costs		$ 225
Performance growth costs after tax		$ 169
Performance growth costs per share, after tax (in dollars per share)		$ 0.61
Current estimated losses	$ 225			225
Classified Fixed-Price Incentive Fee Contract | Rotary and Mission Systems
Change in Accounting Estimate [Line Items]
Performance growth costs	45
Performance growth costs after tax	34
Cumulative losses on development	280			280
EADGE-T
Change in Accounting Estimate [Line Items]
Cumulative losses on development	260			260
Warrior Capability Sustainment Program
Change in Accounting Estimate [Line Items]
Cumulative losses on development	75			75
Decrease in estimated cumulative losses				25
Decrease in estimated cumulative losses, after tax				$ 19
Decrease in estimated cumulative losses (in dollars per share)				$ 0.07
Contracts Accounted for under Percentage of Completion
Change in Accounting Estimate [Line Items]
Increase in operating profit due to profit rate adjustments	580		415	$ 1,500	1,400
Increase in net earnings due to profit rate adjustments	$ 458		$ 328	$ 1,200	$ 1,100
Increase in diluted earnings per common share due to profit rate adjustments (in dollars per share)	$ 1.65		$ 1.17	$ 4.14	$ 3.82