Employee Equity-Based Compensation - Stock Option Activity (Details)	6 Months Ended
Jun. 30, 2018 $ / shares shares
Number of Shares
Granted (shares) \| shares	1,115,371
Forfeited (shares) \| shares	(91,043)
Exercised (shares) \| shares	(253,621)
Expired (shares) \| shares	(5,495)
Outstanding, ending balance (shares) \| shares	8,093,343
Weighted Average Exercise Price per Share
Outstanding, beginning balance (dollars per share)	$ 10.16
Granted (dollars per share)	25.45
Forfeited (dollars per share)	20.97
Exercised (dollars per share)	10.87
Expired (dollars per share)	23.43
Outstanding, ending balance (dollars per share)	$ 12.11

Number of options or other stock instruments for which the right to exercise has lapsed under the terms of the plan agreements.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)(iv)(4)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

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The number of shares under options that were cancelled during the reporting period as a result of occurrence of a terminating event specified in contractual agreements pertaining to the stock option plan.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
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-Subparagraph (c)(1)(iv)(3)
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Gross number of share options (or share units) granted during the period.

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Number of options outstanding, including both vested and non-vested options.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

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Weighted average price at which option holders acquired shares when converting their stock options into shares.

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Weighted average price at which grantees could have acquired the underlying shares with respect to stock options of the plan that expired.

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Weighted average price at which grantees could have acquired the underlying shares with respect to stock options that were terminated.

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Weighted average per share amount at which grantees can acquire shares of common stock by exercise of options.

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Number of share options (or share units) exercised during the current period.

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-Name Accounting Standards Codification
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