v2.4.0.6

Stock-Based Compensation (Tables) | 12 Months Ended
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Dec. 31, 2012
Stock-Based Compensation [Abstract] |
Schedule of Non-Qualified Stock Option Activity | A summary of all of our non-qualified stock option activity for the Calpine Equity Incentive Plans for the year ended December 31, 2012, is as follows:
| Number of Shares |  | Weighted Average Exercise Price |  | Weighted Average Remaining Term (in years) |  | Aggregate Intrinsic Value (in millions)
Outstanding — December 31, 2011 | 17,665,902 |  |  | $ | 17.32 |  |  | 4.8 |  | $ | 26 |
Granted | 898,115 |  |  | $ | 15.35 |  |  |  |  |
Exercised | 348,500 |  |  | $ | 14.94 |  |  |  |  |
Forfeited | 187,716 |  |  | $ | 13.42 |  |  |  |  |
Expired | 165,300 |  |  | $ | 17.77 |  |  |  |  |
Outstanding — December 31, 2012 | 17,862,501 |  |  | $ | 17.30 |  |  | 4.0 |  | $ | 42 |
Exercisable — December 31, 2012 | 10,251,149 |  |  | $ | 19.16 |  |  | 3.6 |  | $ | 12 |
Vested and expected to vest – December 31, 2012 | 17,588,775 |  |  | $ | 17.34 |  |  | 3.9 |  | $ | 41 |
Schedule of Assumptions Used to Estimate Fair Value for Options | Certain assumptions were used in order to estimate fair value for options as noted in the following table.
| 2012 |  | 2011 |  | 2010 |
Expected term (in years)(1) | 6.5 |  |  | 6.5 |  |  | 4.0 – 6.5 |  |
Risk-free interest rate(2) | 1.2 – 1.6 |  | % | 1.7 – 3.2 |  | % | 1.3 – 3.3 |  | %
Expected volatility(3) | 27.0 – 30.5 |  | % | 31.2 – 44.9 |  | % | 31.4 – 37.6 |  | %
Dividend yield(4) | — |  |  | — |  |  | — |  |
Weighted average grant-date fair value (per option) | $ | 5.18 |  |  | $ | 5.49 |  |  | $ | 1.98 |  |
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(1) | Expected term calculated using the simplified method prescribed by the SEC due to the lack of sufficient historical exercise data to provide a reasonable basis to estimate the expected term.
(2) | Zero Coupon U.S. Treasury rate or equivalent based on expected term.
(3) | Volatility calculated using the implied volatility of our exchange traded stock options.
(4) | We have never paid cash dividends on our common stock, and it is not anticipated that any cash dividends will be paid on our common stock in the near future
Schedule of Restricted Stock and Restricted Stock Unit Activity | A summary of our restricted stock and restricted stock unit activity for the Calpine Equity Incentive Plans for the year ended December 31, 2012, is as follows:
| Number of Restricted Stock Awards |  | Weighted Average Grant-Date Fair Value
Nonvested — December 31, 2011 | 3,510,358 |  |  | $ | 12.10 |
Granted | 1,991,894 |  |  | $ | 15.97 |
Forfeited | 297,166 |  |  | $ | 13.70 |
Vested | 1,071,049 |  |  | $ | 10.17 |
Nonvested — December 31, 2012 | 4,134,037 |  |  | $ | 14.33 |

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- Definition Disclosure of the number and weighted-average grant date fair value for restricted stock and restricted stock units that were outstanding at the beginning and end of the year, and the number of restricted stock and restricted stock units that were granted, vested, or forfeited during the year. + References No definition available. + Details
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- Definition Tabular disclosure of the number and weighted-average exercise prices (or conversion ratios) for share options (or share units) that were outstanding at the beginning and end of the year, vested and expected to vest, exercisable or convertible at the end of the year, and the number of share options or share units that were granted, exercised or converted, forfeited, and expired during the year. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(1) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 + Details
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- Definition Tabular disclosure of the significant assumptions used during the year to estimate the fair value of stock options, including, but not limited to: (a) expected term of share options and similar instruments, (b) expected volatility of the entity's shares, (c) expected dividends, (d) risk-free rate(s), and (e) discount for post-vesting restrictions. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (f)(2) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 + Details
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