CONDENSED CONSOLIDATED BALANCE SHEETS (Unaudited) Balance Sheet Parenthetical (USD $) In Millions, unless otherwise specified	Sep. 30, 2013	Dec. 31, 2012
Cash and Cash Equivalents	$ 198	$ 646
Accounts and notes receivable, net	294	222
Other	57	77
Regulatory assets	3,100	3,388
Variable Interest Entity, Primary Beneficiary [Member]
Cash and Cash Equivalents	154	266
Accounts and notes receivable, net	77	68
Other	44	54
Regulatory assets	$ 3,253	$ 3,545