CONDENSED CONSOLIDATED BALANCE SHEETS (Unaudited) Balance Sheet Parenthetical - USD ($) $ in Millions	Jun. 30, 2015	Dec. 31, 2014
Cash and Cash Equivalents	$ 236	$ 290
Allowance for Doubtful Accounts Receivable, Current	2	3
Accounts and notes receivable, net	293	237
Other	43	74
Assets, Noncurrent [Abstract]
Regulatory assets	2,467	2,629
Variable Interest Entity, Primary Beneficiary [Member]
Cash and Cash Equivalents	235	290
Accounts and notes receivable, net	71	58
Other	34	47
Assets, Noncurrent [Abstract]
Regulatory assets	$ 2,581	$ 2,738