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		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Segment Reporting, Asset Reconciling Item [Line Items]
FAS/CAS service cost adjustment	$ 281	$ 279	$ 863	$ 846
Pension FAS/CAS service cost adjustment
Segment Reporting, Asset Reconciling Item [Line Items]
FAS/CAS service cost adjustment	218	208	663	621
Postretirement FAS/CAS service cost adjustment
Segment Reporting, Asset Reconciling Item [Line Items]
FAS/CAS service cost adjustment	$ 63	$ 71	$ 200	$ 225