Income Taxes Deferred Income Taxes (Details 4) - USD ($) $ in Millions	Dec. 31, 2021	Dec. 31, 2020
Deferred Tax Assets (Table Amounts)
Retiree benefits	$ 804	$ 1,738
Accrued employee compensation	371	360
Provisions for accrued liabilities	156	232
Inventory	649	849
Stock-based compensation	39	40
Operating lease liabilities	493	435
Tax credits	431	343
Other	135	112
Gross deferred tax assets	3,078	4,109
Less: valuation allowance	(349)	(307)
Net deferred tax assets	2,729	3,802
Deferred Tax Liabilities (Table Amounts)
Goodwill	533	533
Purchased intangibles	148	201
Property, plant and equipment, net	755	737
Operating lease right-of-use assets	444	423
Contract accounting differences	1,036	1,513
Other	103	84
Deferred tax liabilities	3,019	3,491
Total net deferred tax (liabilities) assets	$ (290)
Total net deferred tax (liabilities) assets		$ 311