Stock-Based Compensation - Narrative (Details) - USD ($) $ in Millions |
6 Months Ended | 12 Months Ended | ||
|---|---|---|---|---|
Jun. 30, 2018 |
Dec. 31, 2018 |
Dec. 31, 2017 |
Dec. 31, 2016 |
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| Share-based Compensation Arrangement by Share-based Payment Award [Line Items] | ||||
| Share-based compensation, number of shares authorized (in shares) | 4,500,000.0 | |||
| Compensation expense | $ 17.5 | |||
| Restricted Stock | ||||
| Share-based Compensation Arrangement by Share-based Payment Award [Line Items] | ||||
| Unrecognized compensation cost | $ 6.2 | |||
| Weighted-average period of unrecognized compensation cost | 17 months | |||
| Compensation expense | $ 5.4 | $ 3.7 | $ 0.5 | |
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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 Weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Unrecognized cost of unvested share-based awards, other than options, awarded to employees as compensation. 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 maximum number of shares (or other type of equity) originally approved (usually by shareholders and board of directors), net of any subsequent amendments and adjustments, for awards under the equity-based compensation plan. As stock or unit options and equity instruments other than options are awarded to participants, the shares or units remain authorized and become reserved for issuance under outstanding awards (not necessarily vested). Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Details
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