v2.3.0.11

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

3 Months Ended

6 Months Ended

Jun. 30, 2011

Jun. 30, 2010

Jun. 30, 2011

Jun. 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

$ 12

$ 57

$ 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

10

^[1]

10

^[1]

6

^[1]

29

^[1]

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

1

^[2]

(3)

^[2]

^[2]

(3)

^[2]

Realized and unrealized gains (losses) included in OCI

4

(5)

5

Purchases, issuances, sales and settlements [Abstract]

Settlements

(7)

(16)

(21)

(22)

Purchases

1

1

Transfers out of level 3

^[3]

^[3]

^[3]

1

^[3]

Balance, end of period

21

43

21

43

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

11

7

7

26

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

Cash equivalents included in cash and cash equivalents

1,144

1,144

1,094

Cash equivalents included in restricted cash

$ 190

$ 190

$ 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]	There were no significant transfers into level 2 or out of level 3 for the three months ended June 30, 2011 and 2010, and the six months ended June 30, 2011. We had $(1) million in losses transferred out of level 3 into level 2 for the six months ended June 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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- Definition

Assets and Liabilities with Recurring Fair Value Measurements Textuals Abstract

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- Definition

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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- Definition

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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- Definition

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

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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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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Purchases 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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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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- Definition

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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- Definition

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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