Summary of Significant Accounting Policies Contract Estimates (Details 5) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended					12 Months Ended
	Sep. 30, 2025	Jun. 30, 2025	Mar. 31, 2025	Sep. 30, 2024	Dec. 31, 2023	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Change in Accounting Estimate [Line Items]
Operating income						$ 4,511	$ 4,370	$ 2,537
Net earnings						$ 4,182	$ 4,174	$ 2,056
Diluted earnings per share						$ 29.08	$ 28.34	$ 13.53
B-21 loss provisions						$ 477	$ 0	$ 1,559
Contracts Accounted for under Percentage of Completion [Member]
Change in Accounting Estimate [Line Items]
Revenue						534	396	298
Operating income						209	350	84
Net earnings						$ 165	$ 277	$ 66
Diluted earnings per share						$ 1.15	$ 1.88	$ 0.43
Contracts Accounted for under Percentage of Completion [Member] | Aeronautics Systems | B-21 Program LRIP Options [Member]
Change in Accounting Estimate [Line Items]
B-21 loss provisions			$ 477		$ 1,560
Loss Contingency, Accrual, Current						$ 1,300
Contracts Accounted for under Percentage of Completion [Member] | Aeronautics Systems | B-21 Program LRIP Options 1-2 [Member]
Change in Accounting Estimate [Line Items]
Operating income	$ 122		$ 226
Contracts Accounted for under Percentage of Completion [Member] | Aeronautics Systems | B-21 Program LRIP Option 1 [Member]
Change in Accounting Estimate [Line Items]
Operating income								$ (143)
Contracts Accounted for under Percentage of Completion [Member] | Defense Systems | Sentinel EMD phase [Member]
Change in Accounting Estimate [Line Items]
Operating income		$ 76
Contracts Accounted for under Percentage of Completion [Member] | Mission Systems [Member] | Restricted Microelectronics Portfolio [Member]
Change in Accounting Estimate [Line Items]
Operating income	$ 68
Contracts Accounted for under Percentage of Completion [Member] | Space Systems | HALO Program [Member]
Change in Accounting Estimate [Line Items]
Operating income				$ 39				$ (100)