Stockholders' Equity - Summary of Assumptions Used to Value Stock Option Grants Using Lattice-Binomial Model (Details) - USD ($) $ / shares in Units, $ in Thousands |
3 Months Ended | 6 Months Ended | ||
|---|---|---|---|---|
Jun. 30, 2015 |
Jun. 30, 2014 |
Jun. 30, 2015 |
Jun. 30, 2014 |
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| Stockholders' Equity and Stock-based Compensation Disclosure [Abstract] | ||||
| Dividend yield | 0.00% | 0.00% | 0.00% | 0.00% |
| Expected volatility | 36.00% | 45.00% | 36.00% | |
| Expected volatility, minimum | 45.00% | |||
| Expected volatility, maximum | 48.00% | |||
| Risk-free interest rate | 2.05% | 2.66% | ||
| Risk-free interest rate, minimum | 2.03% | 2.66% | ||
| Risk-free interest rate, maximum | 2.05% | 2.83% | ||
| Suboptimal exercise factor | 247.00% | |||
| Suboptimal exercise factor, minimum | 2.66% | 2.47% | 2.66% | |
| Suboptimal exercise factor, maximum | 4.20% | 2.48% | 4.20% | |
| Weighted-average fair value (per share) | $ 32.52 | $ 28.13 | $ 29.24 | $ 29.69 |
| Total stock-based compensation expense (in thousands) | $ 28,590 | $ 29,285 | $ 56,031 | $ 55,110 |
| Total income tax benefit related to stock options (in thousands) | $ 10,796 | $ 11,225 | $ 21,188 | $ 21,124 |
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- Definition Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Suboptimal Exercise Factor No definition available.
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- Definition The maximum factor at which the company expects the share price to be compared to the share option exercise price when the employee exercises. No definition available.
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- Definition The minimum factor at which the company expects the share price to be compared to the share option exercise price when the employee exercises. No definition available.
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- Definition Stockholders' Equity and Stock-based Compensation Disclosure [Abstract] No definition available.
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- Definition Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition The total recognized tax benefit related to compensation cost for equity-based payment arrangements recognized in income during the period. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- 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
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- 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
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- Definition The estimated measure of the maximum 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. No definition available.
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- Definition The estimated measure of the minimum 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. No definition available.
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- 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
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- Definition The maximum risk-free interest rate assumption that is used in valuing an option on its own shares. No definition available.
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- Definition The minimum risk-free interest rate assumption that is used in valuing an option on its own shares. No definition available.
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- Definition The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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