v2.4.0.8

Capital Structure (Details) (USD $) | 3 Months Ended | 12 Months Ended
--- | --- | ---
Dec. 31, 2013 | Sep. 30, 2013 | Mar. 31, 2013 | Dec. 31, 2013 | Dec. 31, 2012 | Dec. 31, 2011
Class of Stock [Line Items] |  |  |  |  |  |
Shares Of New, Reorganized Common Stock |  |  |  | 485,000,000 |  |
Common Stock, authorized shares (in shares) | (1,400,000,000) |  |  | (1,400,000,000) | (1,400,000,000) |
Common Stock, issued shares (in shares) | (497,841,056) |  |  | (497,841,056) | (492,495,100) |
Common Stock, par value (in dollars per share) | $ (0.001) |  |  | $ (0.001) | $ (0.001) |
Common Stock, outstanding shares (in shares) | (429,038,988) |  |  | (429,038,988) | (457,048,970) |
Treasury Stock, Shares (in shares) | 68,802,068 |  |  | 68,802,068 | 35,446,130 |
Treasury Stock, Value | $ 1,230,000,000 |  |  | $ 1,230,000,000 | $ 594,000,000 |
Treasury Stock, Value, Acquired, Cost Method | 239,000,000 |  |  | 636,000,000 | 469,000,000 | 120,000,000
Common Stock Activity [Roll Forward] |  |  |  |  |  |
Total common shares outstanding, beginning balance |  |  | (457,048,970) | (457,048,970) | (481,743,738) | (488,693,630)
Resolution of claims/inter-creditor disputes |  |  |  |  |  | 0
Shares issued under Calpine Equity Incentive Plans |  |  |  | 3,022,128 | 1,741,909.000000 | 1,187,181
Share repurchase program |  |  |  | (31,032,110.00000) | (26,436,677.000000) | (8,137,073)
Total common shares outstanding, ending balance | (429,038,988) |  |  | (429,038,988) | (457,048,970) | (481,743,738)
Stock Repurchase Program, Authorized Amount |  | 100,000,000 | 400,000,000 |  | 600,000,000 |
Shares Issued [Member] |  |  |  |  |  |
Common Stock Activity [Roll Forward] |  |  |  |  |  |
Total common shares outstanding, beginning balance |  |  | (492,495,100) | (492,495,100) | (490,468,815) | (444,883,356)
Resolution of claims/inter-creditor disputes |  |  |  |  |  | 44,258,432
Shares issued under Calpine Equity Incentive Plans |  |  |  | 5,345,956 | 2,026,285 | 1,327,027
Share repurchase program |  |  |  | 0 | 0 | 0
Total common shares outstanding, ending balance | (497,841,056) |  |  | (497,841,056) | (492,495,100) | (490,468,815)
Shares Held inTreasury [Member] |  |  |  |  |  |
Common Stock Activity [Roll Forward] |  |  |  |  |  |
Total common shares outstanding, beginning balance |  |  | (35,446,130) | (35,446,130) | (8,725,077) | (448,158)
Resolution of claims/inter-creditor disputes |  |  |  |  |  | 0
Shares issued under Calpine Equity Incentive Plans |  |  |  | 2,323,828 | 284,376 | 139,846
Share repurchase program |  |  |  | (31,032,110) | (26,436,677) | (8,137,073)
Total common shares outstanding, ending balance | (68,802,068) |  |  | (68,802,068) | (35,446,130) | (8,725,077)
Shares Held in Reserve [Member] |  |  |  |  |  |
Common Stock Activity [Roll Forward] |  |  |  |  |  |
Total common shares outstanding, beginning balance |  |  | 0 | 0 | 0 | (44,258,432)
Resolution of claims/inter-creditor disputes |  |  |  |  |  | 44,258,432
Shares issued under Calpine Equity Incentive Plans |  |  |  | 0 | 0 | 0
Share repurchase program |  |  |  | 0 | 0 | 0
Total common shares outstanding, ending balance | 0 |  |  | 0 | 0 | 0
Unfinished Program [Member] |  |  |  |  |  |
Common Stock Activity [Roll Forward] |  |  |  |  |  |
Share repurchase program |  |  |  | (12,459,919) |  |
Treasury Stock Acquired, Average Cost Per Share |  |  |  | $ 19.15 |  |
Stock Repurchase Program, Cumulative Authorized Amount |  |  |  | 1,000,000,000 |  |
Finished Program [Member] |  |  |  |  |  |
Common Stock Activity [Roll Forward] |  |  |  |  |  |
Share repurchase program |  |  |  | (60,139,816) |  |
Treasury Stock Acquired, Average Cost Per Share |  |  |  | $ 18.29 |  |
Stock Repurchase Program, Cumulative Authorized Amount |  |  |  | $ 1,100,000,000 |  |

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