Unaudited Consolidated Consolidated Statements of Cash Flows (USD $) In Millions, unless otherwise specified	3 Months Ended
	Mar. 31, 2012	Mar. 31, 2011
Operating activities
Net income	$ 152	$ 185
Adjustments to reconcile net income to net cash provided by operating activities
Depreciation, amortization and accretion	200	199
Deferred income taxes and investment tax credits, net	107	101
Deferred fuel cost (credit)	(6)	70
Allowance for equity funds used during construction	(24)	(29)
Other adjustments to net income	(7)	56
Cash provided (used) by changes in operating assets and liabilities
Receivables	78	163
Inventory	(10)	(49)
Other assets	(48)	7
Income taxes, net	(7)	57
Accounts payable	23	(89)
Accrued pension and other benefits	(33)	(224)
Other liabilities	(69)	(1)
Net cash provided (used) by operating activities	356	446
Investing activities
Gross property additions	(562)	(501)
Nuclear fuel additions	(51)	(57)
Purchases of available-for-sale securities and other investments	(363)	(1,817)
Proceeds from available-for-sale securities and other investments	359	1,809
Other investing activities	65	46
Net cash provided (used) by investing activities	(552)	(520)
Financing activities
Issuance of common stock, net	3	8
Dividends paid on common stock	(260)	(183)
Proceeds from issuance of short-term debt with original maturities greater than 90 days	65	0
Net increase (decrease) in short-term debt	320	79
Proceeds from issuance of long-term debt, net	444	494
Retirement of long-term debt	0	(700)
Other financing activities	(41)	(63)
Net cash provided (used) by financing activities	531	(365)
Net increase (decrease) in cash and cash equivalents	335	(439)
Cash and cash equivalents at beginning of period	230	611
Cash and cash equivalents at end of period	565	172
Significant noncash transactions
Accrued property additions	225	178
PEC
Operating activities
Net income	52	131
Adjustments to reconcile net income to net cash provided by operating activities
Depreciation, amortization and accretion	162	161
Deferred income taxes and investment tax credits, net	46	69
Deferred fuel cost (credit)	7	29
Allowance for equity funds used during construction	(15)	(20)
Other adjustments to net income	23	12
Cash provided (used) by changes in operating assets and liabilities
Receivables	50	102
Receivables from affiliated companies	(8)	11
Inventory	(5)	(45)
Other assets	(18)	(8)
Income taxes, net	(38)	81
Accounts payable	11	(48)
Payables to affiliated companies	23	(24)
Accrued pension and other benefits	(17)	(147)
Other liabilities	(27)	13
Net cash provided (used) by operating activities	246	317
Investing activities
Gross property additions	(356)	(279)
Nuclear fuel additions	(38)	(50)
Purchases of available-for-sale securities and other investments	(138)	(149)
Proceeds from available-for-sale securities and other investments	133	141
Changes in advances to affiliated companies	0	(1)
Other investing activities	64	5
Net cash provided (used) by investing activities	(335)	(333)
Financing activities
Dividends paid on preferred stock	(1)	(1)
Dividends paid to parent	(175)	(100)
Net increase (decrease) in short-term debt	253	0
Changes in advances from affiliated companies	11	0
Other financing activities	2	0
Net cash provided (used) by financing activities	90	(101)
Net increase (decrease) in cash and cash equivalents	1	(117)
Cash and cash equivalents at beginning of period	20	230
Cash and cash equivalents at end of period	21	113
Significant noncash transactions
Accrued property additions	162	98
PEF
Operating activities
Net income	128	102
Adjustments to reconcile net income to net cash provided by operating activities
Depreciation, amortization and accretion	31	29
Deferred income taxes and investment tax credits, net	53	60
Deferred fuel cost (credit)	(13)	41
Allowance for equity funds used during construction	(9)	(9)
Other adjustments to net income	(20)	35
Cash provided (used) by changes in operating assets and liabilities
Receivables	15	72
Receivables from affiliated companies	(13)	(7)
Inventory	(6)	(5)
Other assets	(27)	19
Income taxes, net	22	63
Accounts payable	14	(45)
Payables to affiliated companies	13	(6)
Accrued pension and other benefits	(14)	(74)
Other liabilities	15	26
Net cash provided (used) by operating activities	189	301
Investing activities
Gross property additions	(197)	(218)
Nuclear fuel additions	(13)	(7)
Purchases of available-for-sale securities and other investments	(225)	(1,659)
Proceeds from available-for-sale securities and other investments	225	1,659
Changes in advances to affiliated companies	(6)	0
Other investing activities	16	42
Net cash provided (used) by investing activities	(200)	(183)
Financing activities
Dividends paid on preferred stock	(1)	(1)
Dividends paid to parent	(105)	(325)
Proceeds from issuance of short-term debt with original maturities greater than 90 days	65	0
Net increase (decrease) in short-term debt	62	0
Changes in advances from affiliated companies	(8)	(2)
Net cash provided (used) by financing activities	13	(328)
Net increase (decrease) in cash and cash equivalents	2	(210)
Cash and cash equivalents at beginning of period	16	249
Cash and cash equivalents at end of period	18	39
Significant noncash transactions
Accrued property additions	$ 60	$ 78