Income Taxes, Deferred Income Tax Assets and Liabilities (Details) - USD ($) $ in Millions	Dec. 31, 2021	Dec. 31, 2020
Deferred income tax assets:
Tax credit carryforwards	$ 679	$ 681
NOLs	697	678
Inventories	217	70
Compensation and employee benefit liabilities	123	199
Environmental liabilities	53	64
Other	149	128
Total deferred income tax assets	1,918	1,820
Valuation allowance	(1,262)	(1,223)
Net deferred income tax assets	656	597
Deferred income tax liabilities:
Property, plant, and equipment	4,866	4,895
Deferred turnaround costs	308	302
Inventories	191	269
Investments	268	171
Other	233	235
Total deferred income tax liabilities	5,866	5,872
Net deferred income tax liabilities	$ 5,210	$ 5,275