Consolidated Statements of Cash Flows (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Cash flows from operating activities:
Net income	$ 104	$ 140	$ 147
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	248	248	227
(Decrease) increase in net liabilities from price risk management activities	(18)	(175)	9
Regulatory deferrals—price risk management activities	18	172	(6)
Cascade Crossing transmission project	52	0	0
Deferred income taxes	11	47	56
Renewable adjustment clause deferrals	0	1	22
Pension and other postretirement benefits	37	27	15
Regulatory deferral of settled derivative instruments	7	(9)	12
Power cost deferrals, net of amortization	(6)	(4)	10
Allowance for equity funds used during construction	(13)	(6)	(5)
Decoupling mechanism deferrals, net of amortization	(6)	2	3
Unrealized gains on non-qualified benefit plan trust assets	3	3	0
Other non-cash income and expenses, net	18	16	16
Changes in working capital:
Increase in receivables and unbilled revenues	0	(4)	(15)
Decrease in margin deposits	37	34	3
Income tax refund received	0	8	9
Increase in payables and accrued liabilities	14	1	5
Other working capital items, net	17	1	(7)
Proceeds received from Trojan spent fuel legal settlement	44	0	0
Contribution to non-qualified employee benefit trust	(6)	0	0
Contribution to voluntary employees’ benefit association trust	(3)	(2)	(16)
Contribution to pension plan	0	0	(26)
Other, net	(14)	(6)	(6)
Net cash provided by operating activities	544	494	453
Cash flows from investing activities:
Capital expenditures	(656)	(303)	(300)
Purchases of nuclear decommissioning trust securities	(26)	(26)	(50)
Sales of nuclear decommissioning trust securities	25	23	46
Contribution to nuclear decommissioning fund	(44)	0	0
Proceeds received from insurance recovery	6	0	0
Proceeds from sale of solar power facility	0	10	0
Other, net	3	2	5
Net cash used in investing activities	(692)	(294)	(299)
Cash flows from financing activities:
Proceeds from Issuance of Long-term Debt	380	0	0
Payments on long-term debt	(100)	(100)	(73)
Proceeds from Issuance of Common Stock, net of issuance costs	67	0	0
Borrowings on short-term debt	35	0	0
Payments on short-term debt	(35)	0	0
(Maturities) issuances of commercial paper, net	(17)	(13)	11
Dividends paid	(84)	(81)	(79)
Premium paid on repayment of long-term debt	0	0	(7)
Debt issuance costs	(3)	0	0
Noncontrolling interests’ capital distributions	0	0	(4)
Net cash provided by (used in) financing activities	243	(194)	(152)
Increase in cash and cash equivalents	95	6	2
Cash and cash equivalents, beginning of year	12	6	4
Cash and cash equivalents, end of year	107	12	6
Supplemental disclosures of cash flow information:
Cash paid for interest, net of amounts capitalized	90	97	103
Cash paid for income taxes	10	13	3
Non-cash investing and financing activities:
Accrued capital additions	84	19	19
Accrued dividends payable	22	21	21
Preliminary engineering transferred to Construction work in progress from Other noncurrent assets	$ 9	$ 0	$ 7