Incentive Plan - Compensation Activity Related to the Management Incentive Plan (Details) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2018 USD ($)	Sep. 30, 2018 USD ($)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation expense	$ 5,570	$ 21,995
Unrecognized compensation expense	22,712	22,712
Fair value of share based awards vested		5,842
Restricted stock awards and restricted stock units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation expense	4,775	18,533
Unrecognized compensation expense	18,465	$ 18,465
Weighted average remaining life		1 year 6 months
Fair value of share based awards vested		$ 5,842
Stock options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation expense	795	3,462
Unrecognized compensation expense	$ 4,247	$ 4,247
Weighted average remaining life		8 years 3 months 18 days
Fair value of share based awards vested		$ 0

No definition available.

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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.

+ References

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- Definition

Unrecognized cost of unvested share-based compensation awards.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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-Topic 718
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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.

+ References

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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.

+ References

No definition available.

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