v2.3.0.15

Our Assets and Liabilities with Recurring Fair Value Measurements (Details Textuals) (USD $)
In Millions

3 Months Ended

9 Months Ended

Sep. 30, 2011

Sep. 30, 2010

Sep. 30, 2011

Sep. 30, 2010

Dec. 31, 2010

Reconciliation of changes in fair value of our net derivative assets (liabilities) classified as level 3

Balance, beginning of period

$ 21

$ 43

$ 30

$ 38

Realized and unrealized gains (losses) included in net income (loss) [abstract]

Realized and unrealized gains (losses) included in net income (loss) included in operating revenues

(8)

^[1]

12

^[1]

(1)

^[1]

31

^[1]

Realized and unrealized gains (losses) included in net income (loss) included in fuel and purchased energy expense

1

^[2]

2

^[2]

1

^[2]

(1)

^[2]

Realized and unrealized gains (losses) included in OCI

(2)

4

3

6

Purchases, issuances, sales and settlements [Abstract]

Settlements

16

(2)

(6)

(13)

Transfers into level 3

^[3]

1

^[3]

^[3]

^[3]

Transfers out of level 3

(1)

^[4]

4

^[4]

^[4]

3

^[4]

Balance, end of period

27

64

27

64

Change in unrealized gains (losses) relating to instruments still held at end of period

(7)

14

30

Assets and Liabilities with Recurring Fair Value Measurements (Textuals) [Abstract]

Cash equivalents included in cash and cash equivalents

1,280

1,280

1,094

Cash equivalents included in restricted cash

$ 211

$ 211

$ 203

[1]	For power contracts and Heat Rate swaps and options, included on our Consolidated Condensed Statements of Operations.
[2]	For natural gas contracts, swaps and options, included on our Consolidated Condensed Statements of Operations.
[3]	We had no significant transfers into level 3 out of level 2 for the three months ended September 30, 2011 and the nine months ended September 30, 2011 and 2010. We had $1 million in gains transferred into level 3 out of level 2 for the three months ended September 30, 2010, due to changes in market liquidity in various power markets.
[4]	We had $1 million in gains and $4 million in losses transferred out of level 3 into level 2 for the three months ended September 30, 2011 and 2010, respectively. We had no significant transfers out of level 3 into level 2 for the nine months ended September 30, 2011. We had $3 million in losses transferred out of level 3 into level 2 for the nine months ended September 30, 2010. Transfers out of level 3 into level 2 were due to changes in market liquidity in various power markets.

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Cash Equivalents Included In Cash And Cash Equivalents, Fair Value Disclosure

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Cash Equivalents Included In Restricted Cash, Fair Value Disclosure

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Fair Value, Assets Measured with Unobservable Inputs on Recurring Basis, Change in Unrealized Gain (Loss) Held At Period End

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- Definition

Fair Value, Assets Measured with Unobservable Inputs on Recurring Basis, Gain (Loss) Included In Fuel And Purchased Energy Expense

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Fair Value, Assets Measured with Unobservable Inputs on Recurring Basis, Gain (Loss) Included in Operating Revenue

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- Definition

This element represents total gains or losses for the period (realized and unrealized), arising from assets measured at fair value on a recurring basis using unobservable inputs (Level 3), which are included in other comprehensive income (a separate component of shareholders' equity).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 157

-Paragraph 32

-Subparagraph c(1)

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.



Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 820

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)(1)

-URI http://asc.fasb.org/extlink&oid=6925170&loc=d3e19207-110258

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Settlements that have taken place during the period in relation to assets measured at fair value and categorized within Level 3 of the fair value hierarchy.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 820

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)(2)

-URI http://asc.fasb.org/extlink&oid=6925170&loc=d3e19207-110258

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Transfers into assets measured at fair value and categorized within Level 3 of the fair value hierarchy that have taken place during the period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 820

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)(3)

-URI http://asc.fasb.org/extlink&oid=6925170&loc=d3e19207-110258

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Transfers out of assets measured at fair value and categorized within Level 3 of the fair value hierarchy that have taken place during the period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 820

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)(3)

-URI http://asc.fasb.org/extlink&oid=6925170&loc=d3e19207-110258

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This element represents an asset measured at fair value using significant unobservable inputs (Level 3) which is required for reconciliation purposes of beginning and ending balances.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 157

-Paragraph 32

-Subparagraph c

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.



Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 820

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)

-URI http://asc.fasb.org/extlink&oid=6925170&loc=d3e19207-110258

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