Financial Information by Business Segment (Details) (USD $) In Millions	3 Months Ended	6 Months Ended
Jun. 30, 2011	Jun. 30, 2010	Jun. 30, 2011	Jun. 30, 2010
Segment Reporting Information [Line Items]
Unaffiliated	$ 2,256	$ 2,372	$ 4,423	$ 4,907
Intersegment	0	0	0	0
Total revenues	2,256	2,372	4,423	4,907
Depreciation, amortization and accretion	179	233	333	479
Interest income	0	1	1	3
Total interest charges, net	180	192	370	374
Ongoing Earnings	211	181	413	395
Total assets	33,120		33,120
PEC
Segment Reporting Information [Line Items]
Unaffiliated	1,060	1,117	2,193	2,380
Intersegment	0	0	0	0
Total revenues	1,060	1,117	2,193	2,380
Ongoing Earnings	112	112	251	260
Total assets	15,154		15,154
PEF
Segment Reporting Information [Line Items]
Unaffiliated	1,193	1,252	2,224	2,522
Intersegment	0	0	1	0
Total revenues	1,193	1,252	2,225	2,522
Ongoing Earnings	141	119	252	232
Total assets	13,907		13,907
Corporate and Other
Segment Reporting Information [Line Items]
Unaffiliated	3	3	6	5
Intersegment	60	53	134	114
Total revenues	63	56	140	119
Ongoing Earnings	(42)	(50)	(90)	(97)
Total assets	20,631		20,631
Eliminations
Segment Reporting Information [Line Items]
Unaffiliated	0	0	0	0
Intersegment	(60)	(53)	(135)	(114)
Total revenues	(60)	(53)	(135)	(114)
Ongoing Earnings	0	0	0	0
Total assets	$ (16,572)		$ (16,572)

The current period expense charged against earnings on long-lived, physical assets used in the normal conduct of business and not intended for resale to allocate or recognize the cost of assets over their useful lives; to record the reduction in book value of an intangible asset over the benefit period of such asset; or to record accretion expense in each subsequent period to recognize asset or liability growth resulting from the passage of time.

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

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Amount of ongoing earnings or loss recognized by the reportable segment. Ongoing earnings, a non-GAAP financial measure, is computed as GAAP net income attributable to controlling interests after excluding discontinued operations and the effects of certain identified gains and charges, which are considered ongoing earnings adjustments.

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- Definition

Interest and debt related expenses associated with nonoperating financing activities of the entity.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 34
-Paragraph 21

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Amount of total assets attributed to the reportable segment.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 131
-Paragraph 27

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Amount of revenue from transactions with other operating segments of the same entity. Must be disclosed if the amount (a) is included in the measure of segment profit or loss reviewed by the chief operating decision maker or (b) is otherwise regularly provided to the chief operating decision maker, even if not included in that measure of segment profit or loss

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 131
-Paragraph 27
-Subparagraph b

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Amount of total revenue for the reportable segment, including revenue from external customers, transactions with other operating segments of the same entity, and (gross) interest revenue. All considered to be "operating revenue" for purposes of the taxonomy.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 131
-Paragraph 27
-Subparagraph a, b, c

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Amount of revenue from external customers for the reportable segment. Must be disclosed if the amounts (a) is included in the measure of segment profit or loss reviewed by the chief operating decision maker or (b) is otherwise regularly provided to the chief operating decision maker, even if not included in that measure of segment profit or loss

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Statement of Financial Accounting Standard (FAS)
-Number 131
-Paragraph 27
-Subparagraph a

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