Segment Information (Unaudited) Reconciliation to Consolidated Operating Income (Details 1) - USD ($) $ in Millions	3 Months Ended		12 Months Ended
	Mar. 31, 2026	Mar. 31, 2025	Dec. 31, 2025
Segment Reporting Information, Revenue for Reportable Segment [Abstract]
Revenues	$ 9,881	$ 9,468
Total operating costs and expenses	8,892	8,895
Operating income	989	573
Interest and Debt Expense	(162)	(156)
Non-operating FAS pension benefit	166	130
Other, net	37	31
Earnings before income taxes	1,030	578
Gain (Loss) on Disposition of Business			$ 231
Product [Member]
Segment Reporting Information, Revenue for Reportable Segment [Abstract]
Revenues	7,958	7,521
Service [Member]
Segment Reporting Information, Revenue for Reportable Segment [Abstract]
Revenues	1,923	1,947
Operating Segments [Member]
Segment Reporting Information, Revenue for Reportable Segment [Abstract]
Operating income	1,072	568
Operating Segments [Member] | Aeronautics Systems [Member]
Segment Reporting Information, Revenue for Reportable Segment [Abstract]
Revenues	3,283	2,814
Operating income	305	(183)
Operating Segments [Member] | Aeronautics Systems [Member] | Product [Member]
Segment Reporting Information, Revenue for Reportable Segment [Abstract]
Total operating costs and expenses	2,294	2,358
Operating Segments [Member] | Aeronautics Systems [Member] | Service [Member]
Segment Reporting Information, Revenue for Reportable Segment [Abstract]
Total operating costs and expenses	653	601
Operating Segments [Member] | Aeronautics Systems [Member] | Intersegment Costs [Member]
Segment Reporting Information, Revenue for Reportable Segment [Abstract]
Total operating costs and expenses	31	38
Operating Segments [Member] | Defense Systems [Member]
Segment Reporting Information, Revenue for Reportable Segment [Abstract]
Revenues	1,899	1,805
Operating income	184	179
Operating Segments [Member] | Defense Systems [Member] | Product [Member]
Segment Reporting Information, Revenue for Reportable Segment [Abstract]
Total operating costs and expenses	1,375	1,262
Operating Segments [Member] | Defense Systems [Member] | Service [Member]
Segment Reporting Information, Revenue for Reportable Segment [Abstract]
Total operating costs and expenses	294	324
Operating Segments [Member] | Defense Systems [Member] | Intersegment Costs [Member]
Segment Reporting Information, Revenue for Reportable Segment [Abstract]
Total operating costs and expenses	46	40
Operating Segments [Member] | Mission Systems [Member]
Segment Reporting Information, Revenue for Reportable Segment [Abstract]
Revenues	2,861	2,807
Operating income	433	361
Operating Segments [Member] | Mission Systems [Member] | Product [Member]
Segment Reporting Information, Revenue for Reportable Segment [Abstract]
Total operating costs and expenses	1,682	1,730
Operating Segments [Member] | Mission Systems [Member] | Service [Member]
Segment Reporting Information, Revenue for Reportable Segment [Abstract]
Total operating costs and expenses	419	434
Operating Segments [Member] | Mission Systems [Member] | Intersegment Costs [Member]
Segment Reporting Information, Revenue for Reportable Segment [Abstract]
Total operating costs and expenses	327	282
Operating Segments [Member] | Space Systems [Member]
Segment Reporting Information, Revenue for Reportable Segment [Abstract]
Revenues	2,480	2,568
Operating income	235	283
Operating Segments [Member] | Space Systems [Member] | Product [Member]
Segment Reporting Information, Revenue for Reportable Segment [Abstract]
Total operating costs and expenses	1,811	1,829
Operating Segments [Member] | Space Systems [Member] | Service [Member]
Segment Reporting Information, Revenue for Reportable Segment [Abstract]
Total operating costs and expenses	281	362
Operating Segments [Member] | Space Systems [Member] | Intersegment Costs [Member]
Segment Reporting Information, Revenue for Reportable Segment [Abstract]
Total operating costs and expenses	153	94
Intersegment OM
Segment Reporting Information, Revenue for Reportable Segment [Abstract]
Operating income	85	72
Segment Reporting, Reconciling Item, Excluding Corporate Nonsegment [Member]
Segment Reporting Information, Revenue for Reportable Segment [Abstract]
Total operating costs and expenses	(90)	(58)
FAS/CAS operating adjustment	$ 7	$ 63