Summary of Significant Accounting Policies (Stock-Based Compensation) (Details) - USD ($) $ in Thousands |
12 Months Ended | ||
|---|---|---|---|
Dec. 31, 2018 |
Dec. 31, 2017 |
Dec. 31, 2016 |
|
| Accounting Policies [Abstract] | |||
| Stock-based compensation expense | $ 28,207 | $ 26,583 | $ 16,128 |
| X | ||||||||||
- References No definition available.
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| X | ||||||||||
- 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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