Schedule I - Condensed Financial Information Of Parent (Balance Sheet) (Details) - USD ($) $ in Millions	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
ASSETS
Cash and cash equivalents	$ 292	$ 5	$ 30	$ 209
Miscellaneous accounts and notes receivable	98	81
Other current assets	88	86
Total current assets	1,917	1,694
Deferred Tax Assets, Net of Valuation Allowance, Noncurrent	6	13
Other non-current assets	575	629
TOTAL ASSETS	23,640	22,289
LIABILITIES AND EQUITY
Short-term debt	301	714
Other current liabilities	379	434
Total current liabilities	2,093	2,249
Long-term Debt, Net	6,880	6,085
Pension and other postretirement benefits	580	705
Other deferred credits and liabilities	$ 531	$ 514
Commitments and Contingencies
Retained earnings	$ 1,331	$ 1,103
Accumulated other comprehensive loss	(3)	(9)
Total equity	7,088	6,855	6,686
TOTAL LIABILITIES AND EQUITY	23,640	22,289
Parent Company
ASSETS
Cash and cash equivalents	0	1	$ 11	$ 23
Advances to money pool	0	55
Accounts receivable - affiliates	53	28
Notes Receivable, Related Parties, Current	0	94
Miscellaneous accounts and notes receivable	3	39
Other current assets	9	14
Total current assets	65	231
Investments in subsidiaries - continuing operations	7,231	6,680
Investments in subsidiaries - discontinued operations	(4)	(4)
Note receivable - affiliates	290	100
Deferred Tax Assets, Net of Valuation Allowance, Noncurrent	426	407
Other non-current assets	158	152
TOTAL ASSETS	8,166	7,566
LIABILITIES AND EQUITY
Short-term debt	301	585
Borrowings from money pool	14	0
Accounts payable – affiliates	75	88
Other current liabilities	22	52
Total current liabilities	412	725
Long-term Debt, Net	694	0
Pension and other postretirement benefits	33	47
Other deferred credits and liabilities	81	81
Total liabilities	1,220	853
Common stock, $.01 par value, 400.0 shares authorized – shares outstanding of 242.6	2	2
Other paid-in capital, principally premium on common stock	5,616	5,617
Retained earnings	1,331	1,103
Accumulated other comprehensive loss	(3)	(9)
Total equity	6,946	6,713
TOTAL LIABILITIES AND EQUITY	$ 8,166	$ 7,566