Condensed Consolidated Statements of Cash Flows (Unaudited) (USD $) In Millions, unless otherwise specified	6 Months Ended
	Jun. 30, 2012	Jun. 30, 2011
Cash flows from operating activities:
Net income	$ 75	$ 91
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	125	111
Increase (decrease) in net liabilities from price risk management activities	(64)	(64)
Regulatory deferral - price risk management activities	63	64
Deferred income taxes	43	33
Pension and other postretirement benefits	14	7
Regulatory deferral of settled derivative instruments	4	12
Power cost deferrals, net of amortization	4	12
Renewable adjustment clause deferrals	0	11
Allowance for equity funds used during construction	(3)	(2)
Other non-cash income and expenses, net	11	4
Changes in working capital:
Decrease (increase) in receivables	42	28
(Increase) decrease in margin deposits, net	11	16
Income tax refund received	8	8
Decrease in payables and accrued liabilities	(57)	(16)
Other working capital items, net	(8)	(5)
Contribution to pension plan	0	(26)
Other, net	(1)	(5)
Net cash provided by operating activities	267	279
Cash flows from investing activities:
Capital expenditures	(137)	(138)
Sale of solar power facility	10	0
Sales of Nuclear decommissioning trust securities	13	29
Purchases of Nuclear decommissioning trust securities	(13)	(31)
Other, net	(1)	1
Net cash used in investing activities	(128)	(139)
Cash flows from financing activities:
Payments on long-term debt	0	(10)
Maturities of commercial paper, net	(30)	(19)
Dividends paid	(41)	(39)
Noncontrolling interests’ capital distributions	0	(4)
Net cash used in financing activities	(71)	(72)
Increase in cash and cash equivalents	68	68
Cash and cash equivalents, beginning of period	6	4
Cash and cash equivalents, end of period	74	72
Supplemental cash flow information is as follows:
Cash paid for interest, net of amounts capitalized	48	51
Cash paid for income taxes	0	3
Non-cash investing and financing activities:
Accrued capital additions	14	24
Increase to Boardman’s asset retirement obligation and cost basis of plant for updated depreciation study	0	23
Accrued dividends payable	21	21
Preliminary engineering transferred to Construction work in progress from Other noncurrent assets	$ 0	$ 7