Stock-based Compensation Plans and Awards - ESPP Narrative (Details) - USD ($) $ in Thousands |
3 Months Ended | |
|---|---|---|
Mar. 31, 2018 |
Mar. 31, 2017 |
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| Share-based Compensation Arrangement by Share-based Payment Award [Line Items] | ||
| Stock-based compensation expense | $ 26,436 | $ 29,618 |
| Employee stock | ||
| 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% | |
| Offering period | 6 months | |
| Contributions from employees withheld | $ 1,400 | 2,800 |
| Stock-based compensation expense | $ 800 | $ 900 |
| Common stock issued (in shares) | 795,990 | 547,765 |
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- 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://www.xbrl.org/2003/role/presentationRef
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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://www.xbrl.org/2003/role/presentationRef
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- Definition Number of shares issued during the period as a result of an employee stock purchase plan. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Details
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