v2.3.0.15
Stock-Based Compensation (Details) (USD $)
3 Months Ended9 Months Ended
Sep. 30, 2011
Sep. 30, 2010
Sep. 30, 2011
Sep. 30, 2010
Summary of non-qualified stock option activity for Calpine Equity Incentive Plans [Abstract]    
Options Outstanding, Beginning balance, Number  17,164,890 
Options Outstanding, Beginning balance, Weighted Average Exercise Price  $ 17.44 
Options Ouststanding, Beginning balance, Weighted Average Remaining Term (in years)  5.6 
Options Outstanding, Beginning balance, Aggregate Intrinsic Value (in $ millions)  $ 8,000,000 
Options granted during the period, number  953,467 
Options granted during the period, Weighted Average Exercise Price$ 14.27 $ 14.27 
Options exercised during the period, Number  7,554 
Options exercised during the period, Weighted Average Exercise Price$ 11.66 $ 11.66 
Options forfeited during the period, Number  179,809 
Options forfeited during the period, Weighted Average Exercise Price$ 13.21 $ 13.21 
Options expired during the period, Number  211,385 
Options expired during the period, Weighted Average Exercise Price$ 17.58 $ 17.58 
Options Outstanding, Ending balance, Number17,719,609 17,719,609 
Options Outstanding, Ending balance, Weighted Average Exercise Price$ 17.31 $ 17.31 
Options Ouststanding, Ending balance, Weighted Average Remaining Term (in years)5.1 5.1 
Options Outstanding, Ending balance, Aggregate Intrinsic Value (in $ millions)12,000,000 12,000,000 
Options Exercisable, Ending balance, Number8,287,446 8,287,446 
Options Exercisable, Ending balance, Weighted Average Exercise Price$ 19.54 $ 19.54 
Options Exercisable, Ending balance, Weighted Average Remaining Term (in years)  4.8 
Options Exercisable, Ending balance, Aggregate Intrinsic Value (in $ millions)1,000,000 1,000,000 
Options Vested and Expected to Vest, Ending balance, Number17,375,455 17,375,455 
Options Vested and Expected to Vest, Ending balance, Weighted Average Exercise Price$ 17.40 $ 17.40 
Options Vested and Expected to Vest, Ending balance, Weighted Average Remaining Term (in years)  5.0 
Options Vested and Expected to Vest, Ending balance, Aggregate Intrinsic Value (in $ millions)12,000,000 12,000,000 
Share-based Compensation Arrangement Fair Value Assumptions and Methodology [Abstract]    
Expected term (in years)  6.5[1]6.5[1]
Dividend yield   [2] [2]
Weighted average grant-date fair value (per option)  $ 5.49$ 1.80
Restricted Stock and Stock Unit Activity [Abstract]    
Nonvested Restricted Stock, Beginning balance, Number  2,683,117 
Nonvested Restricted Stock, Beginning balance, Weighted Average Grant Date Fair Value  $ 11.16 
Nonvested Restricted Stock granted during the period, number  1,636,026 
Nonvested Restricted Stock, granted during the period, Weighted Average Grant Date Fair Value  $ 14.37 
Nonvested Restricted Stock forfeited during the period, Number  238,200 
Nonvested Restricted Stock forfeited during the period, Weighted Average Grant Date Fair Value$ 12.24 $ 12.24 
Nonvested Restricted Stock vested during the period during the period, Number  473,600 
Nonvested Restricted Stock vested during the period, Weighted Average Grant Date Fair Value  $ 14.51 
Nonvested Restricted Stock, Ending balance, Number3,607,343 3,607,343 
Nonvested Restricted Stock, Ending balance, Weighted Average Grant Date Fair Value$ 12.09 $ 12.09 
Stock-Based Compensation (Textuals) [Abstract]    
Vesting period for graded and cliff vesting options - minimum  1 
Vesting period for graded and cliff vesting options - maximum  5 
Contractual terms for the graded and cliff vesting options - minimum  5 
Contractual terms for the graded and cliff vesting options - maximum  10 
Common stock authorized for issuance under the Director Plan567,000 567,000 
Common stock authorized for issuance under the Equity Plan27,533,000 27,533,000 
Percentage of sub-grants representing the total33.30% 33.30% 
First sub-grant vesting term1 1 
Second sub-grant vesting term2 2 
Third sub-grant vesting term3 3 
Number of grants in option grants with three year cliff vesting1 1 
Vesting term of option grants with three year cliff vesting3 3 
Stock-based compensation expense6,000,0006,000,00018,000,00018,000,000
Total FV of vested restricted stock and restricted stock units  7,000,0004,000,000
Minimum
    
Share-based Compensation Arrangement Fair Value Assumptions and Methodology [Abstract]    
Expected term (in years)   4.0[1]
Risk-free interest rate  2.70%[3]2.90%[3]
Expected volatility  31.20%[4]35.00%[4]
Maximum
    
Share-based Compensation Arrangement Fair Value Assumptions and Methodology [Abstract]    
Risk-free interest rate  3.20%[3]3.30%[3]
Expected volatility  44.90%[4]37.60%[4]
Stock options
    
Share-based Compensation Arrangement Fair Value Assumptions and Methodology [Abstract]    
Total unrecognized compensation cost related to share based awards14,000,000 14,000,000 
Weighted average period for share based awards to be recognized  1.6 
Restricted stock
    
Share-based Compensation Arrangement Fair Value Assumptions and Methodology [Abstract]    
Total unrecognized compensation cost related to share based awards19,000,000 19,000,000 
Weighted average period for share based awards to be recognized  1.5 
Restricted stock units
    
Share-based Compensation Arrangement Fair Value Assumptions and Methodology [Abstract]    
Total unrecognized compensation cost related to share based awards$ 1,000,000 $ 1,000,000 
Weighted average period for share based awards to be recognized  0.6 
[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]

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.

[3]

Zero Coupon U.S. Treasury rate or equivalent based on expected term.

[4]

Volatility calculated using the implied volatility of our exchange traded stock options.