v2.4.0.6

Capital Structure (Details) (USD $) In Millions, except Share data, unless otherwise specified | 12 Months Ended | 13 Months Ended |
--- | --- | --- | ---
Dec. 31, 2011 | Dec. 31, 2010 | Dec. 31, 2009 | Feb. 09, 2012 | Feb. 07, 2012
Class of Stock [Line Items] |  |  |  |  |
Shares Of New, Reorganized Common Stock | 485,000,000 |  |  |  |
Common Stock, Shares Authorized | 1,400,000,000 | 1,400,000,000 |  |  |
Common Stock, Shares, Issued | 490,468,815 | 444,883,356 |  |  |
Common Stock, Par or Stated Value Per Share | $ 0.001 | $ 0.001 |  |  |
Common Stock, Shares, Outstanding | 481,743,738 | 444,435,198 |  |  | 481,743,738
Treasury Stock, Shares | 8,725,077 | 448,158 |  |  |
Treasury Stock, Value | $ 125 | $ 5 |  |  |
Stock Repurchase Program, Authorized Amount | 300 |  |  |  |
Treasury Stock, Value, Acquired, Cost Method | $ 120 | $ 2 | $ 2 | $ 124 |
Treasury Stock Acquired, Average Cost Per Share | $ 14.60 |  |  |  |
Common Stock Activity [Roll Forward] |  |  |  |  |
Total common shares outstanding, beginning balance | 488,693,630 | 487,745,299 | 486,874,489 | 488,693,630 |
Resolution of claims/inter-creditor disputes | 0 | 0 | 0 |  |
Shares issued under Calpine Equity Incentive Plans | 1,187,181 | 948,331 | 870,810 |  |
Share repurchase program | 8,137,073 |  |  | 8,524,576 |
Total common shares outstanding, ending balance | 481,743,738 | 488,693,630 | 487,745,299 |  |
Shares Issued [Member] |  |  |  |  |
Common Stock Activity [Roll Forward] |  |  |  |  |
Total common shares outstanding, beginning balance | 444,883,356 | 443,325,827 | 429,025,057 | 444,883,356 |
Resolution of claims/inter-creditor disputes | 44,258,432 | 488,612 | 13,167,420 |  |
Shares issued under Calpine Equity Incentive Plans | 1,327,027 | 1,068,917 | 1,133,350 |  |
Share repurchase program | 0 |  |  |  |
Total common shares outstanding, ending balance | 490,468,815 | 444,883,356 | 443,325,827 |  |
Shares Held inTreasury [Member] |  |  |  |  |
Common Stock Activity [Roll Forward] |  |  |  |  |
Total common shares outstanding, beginning balance | 448,158 | 327,572 | 65,032 | 448,158 |
Resolution of claims/inter-creditor disputes | 0 | 0 | 0 |  |
Shares issued under Calpine Equity Incentive Plans | 139,846 | 120,586 | 262,540 |  |
Share repurchase program | 8,137,073 |  |  |  |
Total common shares outstanding, ending balance | 8,725,077 | 448,158 | 327,572 |  |
Shares Held in Reserve [Member] |  |  |  |  |
Common Stock Activity [Roll Forward] |  |  |  |  |
Total common shares outstanding, beginning balance | 44,258,432 | 44,747,044 | 48,162,203 | 44,258,432 |
Resolution of claims/inter-creditor disputes | 44,258,432 | 488,612 | 3,415,159 |  |
Shares issued under Calpine Equity Incentive Plans | 0 | 0 | 0 |  |
Share repurchase program | 0 |  |  |  |
Total common shares outstanding, ending balance | 0 | 44,258,432 | 44,747,044 |  |
Inter-Creditor Disputes [Member] |  |  |  |  |
Common Stock Activity [Roll Forward] |  |  |  |  |
Total common shares outstanding, beginning balance | 0 | 0 | 9,752,261 | 0 |
Resolution of claims/inter-creditor disputes | 0 | 0 | 9,752,261 |  |
Shares issued under Calpine Equity Incentive Plans | 0 | 0 | 0 |  |
Share repurchase program | 0 |  |  |  |
Total common shares outstanding, ending balance | 0 | 0 | 0 |  |

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