Income Taxes - Schedule of Components of Federal and Foreign Deferred Tax Assets and Liabilities (Details) - USD ($) $ in Millions	Dec. 31, 2025	Dec. 31, 2024
Deferred tax assets related to:
Pensions	$ 999	$ 1,184
Accrued compensation and benefits	764	741
Contract accounting methods	1,217	949
Research and development expenditures	1,200	1,643
Domestic company operating losses	269	83
Other	343	528
Valuation allowance	(60)	(41)
Deferred tax assets, net	4,732	5,087
Deferred tax liabilities related to:
Goodwill and intangible assets	580	545
Property, plant and equipment	512	371
Other	683	638
Deferred tax liabilities	1,775	1,554
Net deferred tax assets	$ 2,957	$ 3,533