v2.4.0.6

Income Taxes (Income Tax Expense (Benefit)) (Details) (USD $) | 3 Months Ended | 9 Months Ended | 12 Months Ended
--- | --- | --- | ---
Sep. 30, 2012 | Sep. 30, 2011 | Sep. 30, 2012 | Sep. 30, 2011 | Dec. 31, 2011
Income Tax Disclosure [Abstract] |  |  |  |  |  |
Operating Loss Carryforwards Available To Offset Future Income |  |  |  |  |  | $ 6,300,000,000
One time tax benefit from consolidation |  |  |  | 76,000,000 |  |
Income tax expense (benefit) | 81,000,000 | 20,000,000 | 23,000,000 | (45,000,000) | [1] |
Effective Income Tax Rate, Continuing Operations | 16.00% | 10.00% | 19.00% | 20.00% |  |
Income Tax Expense (Benefit), Intraperiod Tax Allocation | 3,000,000 | 36,000,000 | 7,000,000 | 20,000,000 |  |
Other Comprehensive Income (Loss), Tax | (3,000,000) | (34,000,000) | (7,000,000) | (18,000,000) |  |
NOLs expected to expire unutilized related to pre-emergence date NOLs |  |  |  |  |  | 640,000,000
NOLs expected to expire unutilized due to carryforward time constraints |  |  | 50,000,000 |  |  |
Percent Decline In Market Cap Required To Trigger Transfer Restrictions | 35.00% |  | 35.00% |  |  |
Emergence Date Capitalization | 8,600,000,000 |  | 8,600,000,000 |  |  |
Percent Change in Ownership Required To Trigger Transfer Restrictions | 25.00% |  | 25.00% |  |  |
Holders with ownership that could be affected by transfer restrictions | 5.00% |  | 5.00% |  |  |
Unrecognized Tax Benefits | 92,000,000 |  | 92,000,000 |  |  |
Unrecognized Tax Benefits that Would Impact Effective Tax Rate | 47,000,000 |  | 47,000,000 |  |  |
Unrecognized Tax Benefits Resulting in Net Operating Loss Carryforward | 45,000,000 |  | 45,000,000 |  |  |
Unrecognized Tax Benefits, Income Tax Penalties and Interest Accrued | 23,000,000 |  | 23,000,000 |  |  |
Unrecognized Tax Benefits, Increases Resulting from Prior Period Tax Positions |  |  | 18,000,000 |  |  |
Significant Change in Unrecognized Tax Benefits is Reasonably Possible, Estimated Range of Change, Lower Bound | 0 |  | 0 |  |  |
Significant Change in Unrecognized Tax Benefits is Reasonably Possible, Estimated Range of Change, Upper Bound | 23,000,000 |  | 23,000,000 |  |  |
Tax refund due to foreign dividend income treatment | 10,000,000 |  | 10,000,000 |  |  |
Tax refund plus accrued interest due to foreign dividend income treatment | 13,000,000 |  | 13,000,000 |  |  |
Accrued interest on foreign dividend refund | $ 3,000,000 |  | $ 3,000,000 |  |  |
[1] | approximately $76 million related to the election to consolidate our CCFC and Calpine groups for federal income tax reporting purposes for the nine months ended September 30, 2011.

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