Supplemental Information To Statements Of Cash Flows (Schedule Of Supplemental Information To Statements Of Cash Flows) (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Changes in assets and liabilities, net:
Accounts receivable	$ (457)	$ (63)
Other current assets	64	(10)
Other long-term assets	66	(10)
Accounts payable and revenues and royalties payable	247	16
Other current liabilities	8	(33)
Other long-term liabilities	(71)	(27)
Total	(143)	(127)
Supplementary cash flow data - total operations:
Interest paid	100	114
Income taxes paid (refunded)	$ (23)	$ (6)