v2.4.0.6
Stock-Based Compensation (Tables)
 12 Months Ended
Dec. 31, 2011
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, 2011, is as follows:
 
Number of
Shares
 
Weighted Average
Exercise Price
 
Weighted
Average
Remaining
Term
(in years)
 
Aggregate
Intrinsic Value
(in millions)
Outstanding — December 31, 2010
17,164,890

 
$
17.44

 
5.6

 
$
8

Granted
953,467

 
$
14.27

 
 
 
 
Exercised
7,554

 
$
11.66

 
 
 
 
Forfeited
197,316

 
$
13.04

 
 
 
 
Expired
247,585

 
$
17.56

 
 
 
 
Outstanding — December 31, 2011
17,665,902

 
$
17.32

 
4.8

 
$
26

Exercisable — December 31, 2011
8,297,284

 
$
19.49

 
4.6

 
$
2

Vested and expected to vest – December 31, 2011
17,377,738

 
$
17.39

 
4.7

 
$
25
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.
 
2011
 
2010
 
2009
 
Expected term (in years)(1)
6.5

 
4.0 – 6.5

 
6.0 – 6.5

 
Risk-free interest rate(2)
1.7 – 3.2

%
1.3 – 3.3

%
2.3 – 2.9

%
Expected volatility(3)
31.2 – 44.9

%
31.4   – 37.6

%
52.1 – 73.0

%
Dividend yield(4)
—

 
—

 
—

 
Weighted average grant-date fair value (per option)
$
5.49

 
$
1.98

 
$
5.67

 
___________
(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, 2011, is as follows:
 
Number of
Restricted
Stock Awards
 
Weighted
Average
Grant-Date
Fair Value
Nonvested — December 31, 2010
2,683,117

2,046,599

$
11.16

Granted
1,636,026

1,475,992

$
14.37

Forfeited
322,034

400,141

$
12.32

Vested
486,751

439,333

$
14.41

Nonvested — December 31, 2011
3,510,358

 
$
12.10