Supplemental Balance Sheet Information (Tables)

3 Months Ended

Mar. 31, 2012

Supplemental Balance Sheet Information [Abstract]

Inventories

(millions)	As of March 31, 2012		As of December 31, 2011
Finished goods and work in progress		$    253		$    239
Raw materials		60		66
Total		$    313		$    305

Changes in the liability for asset retirement obligations

		$000,000,000,00		$000,000,000,00
	Three Months               ended March 31,
(millions)	2012		2011
Balance as of January 1		$    114		$    103
Accretion expense		2		2
Liabilities incurred/adjusted		(1)		-
Liabilities settled		-		-
Balance as of March 31		$    115		$    105