Stock-Based Compensation - Summary of Stock Option Exercises (Details) - USD ($) $ in Millions |
12 Months Ended | ||
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Dec. 31, 2018 |
Dec. 31, 2017 |
Dec. 31, 2016 |
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| Disclosure of Compensation Related Costs, Share-based Payments [Abstract] | |||
| Total intrinsic value of stock options exercised | $ 0.3 | $ 0.5 | |
| Cash proceeds received from options exercised | $ 0.8 | $ 1.4 | $ 0.3 |
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- References No definition available.
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- Definition Amount of cash inflow from exercise of stock options granted under share-based compensation arrangement. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Amount of accumulated difference between fair value of underlying shares on dates of exercise and exercise price on options exercised (or share units converted) into shares. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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