v3.8.0.1

Stock-Based Compensation (Tables) | 9 Months Ended
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Sep. 30, 2017
Disclosure of Compensation Related Costs, Share-based Payments [Abstract] |
Share-based Compensation, Stock Options, Activity [Table Text Block] | A summary of all of our non-qualified stock option activity for the Equity Plans for the nine months ended September 30, 2017, is as follows:
| Number of Shares |  | Weighted Average Exercise Price |  | Weighted Average Remaining Term (in years) |  | Aggregate Intrinsic Value (in millions)
Outstanding — December 31, 2016 | 2,697,136 |  |  | $ | 13.59 |  |  | 3.0 |  | $ | 2 |
Granted | 1,476,480 |  |  | $ | 11.70 |  |  |  |  |
Exercised | 4,000 |  |  | $ | 9.49 |  |  |  |  |
Forfeited | 15,721 |  |  | $ | 11.69 |  |  |  |  |
Expired | 32,100 |  |  | $ | 17.70 |  |  |  |  |
Outstanding — September 30, 2017 | 4,121,795 |  |  | $ | 12.89 |  |  | 4.8 |  | $ | 10 |
Exercisable — September 30, 2017 | 2,661,036 |  |  | $ | 13.54 |  |  | 2.3 |  | $ | 5 |
Vested and expected to vest – September 30, 2017 | 3,949,676 |  |  | $ | 12.94 |  |  | 4.6 |  | $ | 9 |
Schedule of Share-based Payment Award, Stock Options, Valuation Assumptions [Table Text Block] | Certain assumptions were used in order to estimate fair value for options as noted in the following table:
| 2017 |
Expected term (in years)(1) | 7.3 - 10.0 |  |
Risk-free interest rate(2) | 2.25 |  | %
Expected volatility(3) | 33 - 40 |  | %
Dividend yield(4) | — |  |
Weighted average grant-date fair value (per option) | $ | 5.38 |  |
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(1) | Expected term calculated using historical exercise data.
(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 we do not anticipate any cash dividend payments on our common stock in the near future.
Schedule of Share-based Compensation, Restricted Stock and Restricted Stock Units Activity [Table Text Block] | A summary of our restricted stock and restricted stock unit activity for the Calpine Equity Incentive Plans for the nine months ended September 30, 2017, is as follows:
| Number of Restricted Stock Awards |  | Weighted Average Grant-Date Fair Value
Nonvested — December 31, 2016 | 4,869,648 |  |  | $ | 15.83 |
Granted | 3,606,816 |  |  | $ | 11.76 |
Forfeited | 546,585 |  |  | $ | 13.90 |
Vested | 1,674,738 |  |  | $ | 17.07 |
Nonvested — September 30, 2017 | 6,255,141 |  | (1) | $ | 13.31 |
___________
(1) | Includes 63,075 shares of restricted stock and restricted stock units outstanding under the Director Plans and 6,192,066 shares of restricted stock and restricted stock units outstanding under the Equity Plans
Schedule of Share-based Compensation, Activity | A summary of our performance share unit activity for the nine months ended September 30, 2017, is as follows:
| Number of Performance Share Units |  | Weighted Average Grant-Date Fair Value
Nonvested — December 31, 2016 | 890,587 |  |  | $ | 17.90 |
Granted | 478,984 |  |  | $ | 10.73 |
Forfeited | 54,638 |  |  | $ | 18.38 |
Vested(1) | 30,312 |  |  | $ | 17.21 |
Nonvested — September 30, 2017 | 1,284,621 |  |  | $ | 15.22 |
___________
(1) | In accordance with the applicable performance share unit agreements, performance share units granted to employees who meet the retirement eligibility requirements stipulated in the Equity Plans are fully vested upon the later of the date on which the employee becomes eligible to retire or one-year anniversary of the grant date.

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- Definition Tabular disclosure for share-based compensation plans. Includes, but is not limited to, outstanding awards at beginning and end of year, grants, exercises, forfeitures, and weighted-average grant date fair value. + 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)(2) -URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (e) -URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901 + Details
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- Definition Tabular disclosure for stock option plans. Includes, but is not limited to, outstanding awards at beginning and end of year, grants, exercises, forfeitures, and weighted-average grant date fair value. + 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 (d) -URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (e) -URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901 Reference 3: 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=96867065&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=96867065&loc=d3e5070-113901 + Details
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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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