Condensed Consolidated Statements Of Comprehensive Income (USD $) In Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2011	Jun. 30, 2010	Jun. 30, 2011	Jun. 30, 2010
Condensed Consolidated Statements Of Comprehensive Income
Net income	$ 510	$ 255	$ 347	$ 993
Other comprehensive income, net of income tax:
Change in fair value of derivative instruments, net of income taxes of $87 million, ($38) million, $89 million and $114 million	141	(62)	146	187
Reclassification of gain on settled contracts, net of income taxes of ($11) million, ($82) million, ($39) million and ($135) million	(18)	(134)	(64)	(221)
Ineffective portion of derivatives qualifying for cash flow hedge accounting, net of income taxes of ($3) million, $7 million, ($7) million and $9 million	(5)	11	(11)	15
Unrealized gain (loss) on marketable securities, net of income taxes of ($3) million, ($3) million, ($1) million and ($5) million	(5)	(5)	(2)	(8)
Comprehensive income	$ 623	$ 65	$ 416	$ 966