Segment and Revenue Information - Components of Financial Accounting Standards and Cost Accounting Standards Adjustment (Details) - Unallocated items, eliminations and other - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2026	Mar. 31, 2025
Segment Reporting, Asset Reconciling Item [Line Items]
FAS/CAS service cost adjustment	$ 155	$ 262
Pension FAS/CAS service cost adjustment
Segment Reporting, Asset Reconciling Item [Line Items]
FAS/CAS service cost adjustment	93	193
Other Postretirement Plans
Segment Reporting, Asset Reconciling Item [Line Items]
FAS/CAS service cost adjustment	$ 62	$ 69