Schedule I Condensed Financial Information Parent Company Statements of Cash Flows (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Condensed Financial Statements [Line Items]
Total Cash Flows from Operating Activities	$ 938	$ 1,038	$ 773
Cash Flows from Investing Activities:
Capital Expenditures	(1,168)	(1,127)	(1,043)
Asset Dispositions	25	16	76
Decrease (Increase) in Restricted Cash	14	11	(25)
Capital Contributions Received and Loans Incurred	0	0	0
Capital Redemptions and Loans Paid	0	0	0
Other Transactions	0	4	(1)
Total Cash Flows from Investing Activities	(1,136)	(1,123)	(902)
Cash Flows from Financing Activities:
Short Term Debt and Overdrafts Incurred	31	77	179
Short Term Debt and Overdrafts Paid	(120)	(156)	(138)
Long Term Debt Incurred	1,913	3,531	3,171
Long Term Debt Paid	(681)	(3,717)	(2,650)
Proceeds from Issuance of Preferred Stock	0	0	484
Preferred Stock Dividends Paid	(29)	(29)	(15)
Common Stock Issued	22	3	8
Common Stock Dividends Paid	(12)	0	0
Capital Contributions Received and Loans Incurred	0	0	0
Capital Redemptions and Loans Paid	0	0	0
Transactions with Minority Interests in Subsidiaries	(26)	(71)	(24)
Debt Related Costs and Other Transactions	(16)	(64)	(21)
Total Cash Flows from Financing Activities	1,082	(426)	994
Net Change in Cash and Cash Equivalents	715	(491)	767
Cash and Cash Equivalents at Beginning of the Year	2,281	2,772	2,005
Cash and Cash Equivalents at End of the Year	2,996	2,281	2,772
Parent Company
Condensed Financial Statements [Line Items]
Total Cash Flows from Operating Activities	17	335	260
Cash Flows from Investing Activities:
Capital Expenditures	(220)	(231)	(210)
Asset Dispositions	2	5	69
Decrease (Increase) in Restricted Cash	0	1	(1)
Capital Contributions Received and Loans Incurred	(91)	(191)	(14)
Capital Redemptions and Loans Paid	214	81	0
Other Transactions	0	4	(1)
Total Cash Flows from Investing Activities	(95)	(331)	(157)
Cash Flows from Financing Activities:
Short Term Debt and Overdrafts Incurred	14	0	0
Short Term Debt and Overdrafts Paid	(90)	0	0
Long Term Debt Incurred	900	800	400
Long Term Debt Paid	(11)	(762)	(750)
Proceeds from Issuance of Preferred Stock	0	0	484
Preferred Stock Dividends Paid	(29)	(29)	(15)
Common Stock Issued	22	3	8
Common Stock Dividends Paid	(12)	0	0
Capital Contributions Received and Loans Incurred	170	150	(101)
Capital Redemptions and Loans Paid	(403)	(200)	0
Transactions with Minority Interests in Subsidiaries	0	(17)	(3)
Debt Related Costs and Other Transactions	(16)	(63)	(2)
Total Cash Flows from Financing Activities	545	(118)	21
Net Change in Cash and Cash Equivalents	467	(114)	124
Cash and Cash Equivalents at Beginning of the Year	802	916	792
Cash and Cash Equivalents at End of the Year	$ 1,269	$ 802	$ 916