Stock-based Compensation Plans and Awards - ESPP Narrative (Details) - USD ($) $ in Thousands |
3 Months Ended | 9 Months Ended | ||
|---|---|---|---|---|
Sep. 30, 2018 |
Sep. 30, 2017 |
Sep. 30, 2018 |
Sep. 30, 2017 |
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| Share-based Compensation Arrangement by Share-based Payment Award [Line Items] | ||||
| Stock-based compensation expense | $ 28,838 | $ 30,101 | $ 82,802 | $ 98,327 |
| ESPP | ||||
| Share-based Compensation Arrangement by Share-based Payment Award [Line Items] | ||||
| Percentage of eligible compensation to purchase common stock through payroll deductions (as a percent) | 15.00% | 15.00% | ||
| Offering period | 6 months | |||
| Contributions from employees withheld | $ 1,900 | 1,900 | $ 5,500 | 8,000 |
| Stock-based compensation expense | $ 900 | $ 1,000 | $ 2,500 | $ 2,900 |
| Common stock issued (in shares) | 739,922 | 855,415 | 1,651,405 | 1,287,687 |
| X | ||||||||||
- Definition Represents the amount of contributions from employees withheld. No definition available.
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- Definition Represents the offering period for award under the share based compensation. 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://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. No definition available.
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- Definition The highest percentage of annual salary that an employee is permitted to utilize with respect to the plan. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Number of shares issued during the period as a result of an employee stock purchase plan. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Details
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