Income Taxes (Components Of Deferred Tax Assets And Liabilities) (Details) - USD ($) $ in Millions	Dec. 31, 2021	Dec. 31, 2020
Deferred tax assets:
Employee benefits	$ 495	$ 647
Environmental remediation	91	95
Finance lease obligations	339	103
Operating lease liabilities	263	453
Net operating loss carryforwards	113	232
Tax credit carryforwards	19	19
Goodwill and other intangibles	35	0
Other	67	80
Total deferred tax assets	1,422	1,629
Deferred tax liabilities:
Property, plant and equipment	2,716	3,195
Inventories	717	800
Investments in subsidiaries and affiliates	3,350	3,331
Goodwill and other intangibles	0	34
Right of use assets	257	451
Other	18	18
Total deferred tax liabilities	7,058	7,829
Net deferred tax liabilities	$ 5,636	$ 6,200