Unaudited Condensed Consolidated Statements of Comprehensive Income (USD $) In Millions, except Per Share data, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2012	Jun. 30, 2011	Jun. 30, 2012	Jun. 30, 2011
Statement of Comprehensive Income [Line Items]
Operating revenues	$ 2,273	$ 2,256	$ 4,365	$ 4,423
Operating expenses
Fuel used in electric generation	736	674	1,421	1,392
Purchased power	257	329	467	549
Operation and maintenance	627	510	1,156	1,004
Depreciation, amortization and accretion	231	179	397	333
Taxes other than on income	142	134	280	274
Other	5	2	5	(8)
Total operating expenses	1,998	1,828	3,726	3,544
Operating income	275	428	639	879
Other income (expense)
Interest income	1	0	2	1
Allowance for equity funds used during construction	25	26	49	55
Other, net	1	7	14	10
Total other income, net	27	33	65	66
Interest charges
Interest charges	203	189	397	388
Allowance for borrowed funds used during construction	(11)	(9)	(20)	(18)
Total interest charges, net	192	180	377	370
Income from continuing operations before income tax	110	281	327	575
Income tax expense	42	101	118	208
Income from continuing operations	68	180	209	367
Discontinued operations, net of tax	(4)	(2)	7	(4)
Net income	64	178	216	363
Net income attributable to noncontrolling interests, net of tax	(1)	(2)	(3)	(3)
Net income attributable to controlling interests	63	176	213	360
Average common shares outstanding - basic	297	296	297	295
Basic and diluted earnings per common share
Income from continuing operations attributable to controlling interests, net of tax	$ 0.23	$ 0.60	$ 0.70	$ 1.23
Discontinued operations attributable to controlling interests, net of tax	$ (0.02)	$ 0.00	$ 0.02	$ (0.01)
Net income attributable to controlling interests	$ 0.21	$ 0.60	$ 0.72	$ 1.22
Dividends declared per common share	$ 0.620	$ 0.620	$ 1.240	$ 1.240
Net income amounts attributable to controlling interests
Income from continuing operations, net of tax	67	178	206	364
Discontinued operations, net of tax	(4)	(2)	7	(4)
Net income attributable to controlling interests	63	176	213	360
Comprehensive income
Comprehensive income	60	157	217	346
Comprehensive (income) loss attributable to noncontrolling interests, net of tax	(1)	(2)	(3)	(3)
Comprehensive income attributable to controlling interests	59	155	214	343
PEC
Statement of Comprehensive Income [Line Items]
Operating revenues	1,082	1,060	2,167	2,193
Operating expenses
Fuel used in electric generation	346	326	695	689
Purchased power	80	73	145	140
Operation and maintenance	386	293	760	588
Depreciation, amortization and accretion	134	126	268	250
Taxes other than on income	52	50	108	106
Other	3	0	2	0
Total operating expenses	1,001	868	1,978	1,773
Operating income	81	192	189	420
Other income (expense)
Interest income	0	1	0	1
Allowance for equity funds used during construction	17	18	32	38
Other, net	1	1	5	(1)
Total other income, net	18	20	37	38
Interest charges
Interest charges	59	54	115	104
Allowance for borrowed funds used during construction	(6)	(6)	(11)	(11)
Total interest charges, net	53	48	104	93
Income from continuing operations before income tax	46	164	122	365
Income tax expense	15	57	39	127
Net income	31	107	83	238
Preferred stock dividend requirement	0	0	(1)	(1)
Net income available to parent	31	107	82	237
Comprehensive income
Comprehensive income attributable to controlling interests	25	102	82	235
PEF
Statement of Comprehensive Income [Line Items]
Operating revenues	1,189	1,193	2,194	2,225
Operating expenses
Fuel used in electric generation	390	348	726	703
Purchased power	177	256	322	409
Operation and maintenance	246	224	406	434
Depreciation, amortization and accretion	92	48	119	73
Taxes other than on income	90	83	172	168
Other	(2)	0	(2)	(12)
Total operating expenses	993	959	1,743	1,775
Operating income	196	234	451	450
Other income (expense)
Interest income	1	0	1	0
Allowance for equity funds used during construction	8	8	17	17
Other, net	0	1	0	4
Total other income, net	9	9	18	21
Interest charges
Interest charges	74	68	141	137
Allowance for borrowed funds used during construction	(5)	(3)	(9)	(7)
Total interest charges, net	69	65	132	130
Income from continuing operations before income tax	136	178	337	341
Income tax expense	53	65	126	126
Net income	83	113	211	215
Preferred stock dividend requirement	0	0	(1)	(1)
Net income available to parent	83	113	210	214
Comprehensive income
Comprehensive income attributable to controlling interests	$ 82	$ 108	$ 211	$ 210