|
Benefit Plans (Details) (Employee Stock Option [Member])
|
3 Months Ended | 9 Months Ended | ||
|---|---|---|---|---|
|
Sep. 30, 2013
|
Sep. 30, 2012
|
Sep. 30, 2013
|
Sep. 30, 2012
|
|
|
Employee Stock Option [Member]
|
||||
| Fair value of options granted to employees and members of our board of directors | ||||
| Risk-free interest rate | 1.50% | 0.80% | 1.40% | 0.80% |
| Expected life of options — years | 4 years 8 months 23 days | 5 years 22 days | 4 years 8 months 19 days | 5 years 1 month 17 days |
| Expected stock price volatility | 47.00% | 49.00% | 48.00% | 53.00% |
| Expected dividend yield | 0.00% | 0.00% | 0.00% | 0.00% |
| X | ||||||||||
|
- Details
|
| X | ||||||||||
|
- Definition
The estimated dividend rate (a percentage of the share price) to be paid (expected dividends) to holders of the underlying shares over the option's term. Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
| X | ||||||||||
|
- Definition
Expected term of share-based compensation awards, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
| X | ||||||||||
|
- Definition
The estimated measure of the percentage by which a share price is expected to fluctuate during a period. Volatility also may be defined as a probability-weighted measure of the dispersion of returns about the mean. The volatility of a share price is the standard deviation of the continuously compounded rates of return on the share over a specified period. That is the same as the standard deviation of the differences in the natural logarithms of the stock prices plus dividends, if any, over the period. Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
| X | ||||||||||
|
- Definition
The risk-free interest rate assumption that is used in valuing an option on its own shares. Reference 1: http://www.xbrl.org/2003/role/presentationRef
|