Equity-Based Compensation - Summary of Activity Related to Stock Options (Details) - Stock Options - $ / shares	6 Months Ended
Jun. 30, 2019	Jun. 30, 2018
Number Outstanding
Outstanding at January 1,	2,017,067	2,436,232
Exercises	(351,101)	(343,780)
Forfeitures or expirations	(3,000)	(60,035)
Outstanding at June 30,	1,662,966	2,032,417
Weighted-Average Exercise Price Per Share
Outstanding at January 1,	$ 16.70	$ 16.70
Exercises	16.70	16.70
Forfeitures or expirations	16.70	16.70
Outstanding at June 30,	$ 16.70	$ 16.70

For presentations that combine terminations, 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 or that expired.

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Weighted average price of options that were either forfeited or expired.

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

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
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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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Number of share options (or share units) exercised during the current period.

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