Financial Information by Business Segment (Details) (USD $) In Millions	3 Months Ended	9 Months Ended
Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2011	Sep. 30, 2010	Dec. 31, 2010
Segment Reporting Information [Line Items]
Unaffiliated	$ 2,747	$ 2,962	$ 7,170	$ 7,869
Intersegment	0	0	0	0
Total revenues	2,747	2,962	7,170	7,869
Depreciation, amortization and accretion	175	201	508	680
Interest income	1	3	2	6
Total interest charges, net	172	189	542	563
Income tax (benefit) expense	178	219	386	456
Ongoing Earnings	344	361	757	756
Total assets	33,677		33,677		33,054
PEC
Segment Reporting Information [Line Items]
Unaffiliated	1,332	1,414	3,525	3,794
Intersegment	0	0	0	0
Total revenues	1,332	1,414	3,525	3,794
Ongoing Earnings	202	233	453	493
Total assets	15,543		15,543
PEF
Segment Reporting Information [Line Items]
Unaffiliated	1,413	1,543	3,637	4,064
Intersegment	1	0	2	1
Total revenues	1,414	1,543	3,639	4,065
Ongoing Earnings	202	177	454	409
Total assets	14,014		14,014
Corporate and Other
Segment Reporting Information [Line Items]
Unaffiliated	2	5	8	11
Intersegment	69	66	203	179
Total revenues	71	71	211	190
Ongoing Earnings	(60)	(49)	(150)	(146)
Total assets	20,954		20,954
Eliminations
Segment Reporting Information [Line Items]
Unaffiliated	0	0	0	0
Intersegment	(70)	(66)	(205)	(180)
Total revenues	(70)	(66)	(205)	(180)
Ongoing Earnings	0	0	0	0
Total assets	$ (16,834)		$ (16,834)

Includes all interest income, including impacts of discount accretion and premium amortization, and dividend income.

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