Consolidated Statements of Cash Flows Statement (USD $) In Millions, unless otherwise specified	6 Months Ended
	Jun. 30, 2014	Jun. 30, 2013
Cash flows from operating activities:
Net income	$ 339	$ 326
Adjustments to reconcile net income to net cash flows from operating activities:
Depreciation and amortization	356	337
Deferred income taxes and amortization of investment tax credits	105	78
Changes in regulatory assets and liabilities	(43)	(7)
Other, net	(19)	(20)
Changes in other operating assets and liabilities:
Accounts receivable and other assets	45	69
Derivative collateral, net	12	23
Inventories	18	(19)
Income taxes	18	(11)
Accounts payable and other liabilities	55	55
Net cash flows from operating activities	886	831
Cash flows from investing activities:
Capital expenditures	(532)	(518)
Other, net	(3)	6
Net cash flows from investing activities	(535)	(512)
Cash flows from financing activities:
Proceeds from long-term debt	425	299
Repayments of long-term debt and capital lease obligations	(13)	(71)
Redemption of preferred stock	0	(5)
Common stock dividends	(625)	(500)
Other, net	(3)	(3)
Net cash flows from financing activities	(216)	(280)
Net change in cash and cash equivalents	135	39
Cash and cash equivalents at beginning of period	53	80
Cash and cash equivalents at end of period	$ 188	$ 119