Supplemental Information To Statements Of Cash Flows (Tables)

12 Months Ended

Dec. 31, 2017

Supplemental Cash Flow Elements [Abstract]

Schedule Of Supplemental Information To Statements Of Cash Flows

	Year Ended December 31,
	2017			2016			2015
Net change in working capital accounts,     net of assets and liabilities assumed:
Accounts receivable	$	(284	)	$	(176	)	$	942
Income taxes receivable		8			130			384
Other current assets		(12	)		215			(57	)
Accounts payable		105			(167	)		(190	)
Revenues and royalties payable		257			96			(526	)
Other current liabilities		(53	)		(74	)		(818	)
Net change in working capital	$	21		$	24		$	(265	)
Interest paid (net of capitalized interest)	$	481		$	569		$	497
Income taxes paid (received)	$	78		$	(159	)	$	(279	)