Equity - Equity-Based Incentive Compensation - Performance Awards (Details) - USD ($) $ in Thousands	3 Months Ended
Jun. 30, 2018	Jun. 30, 2017
Performance awards
Equity-Based Incentive Compensation
Expense recorded	$ 1,300	$ 2,100
Estimated future equity-based compensation expense
2019 (nine months)	2,609
2020	1,904
2021	383
Total	$ 4,896
Restricted units
Equity-Based Incentive Compensation
Number of units available for grant	1,300,000
Vesting on July 1, 2018 \| Performance awards
Equity-Based Incentive Compensation
Units vested and issued (in units)	0

No definition available.

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- Definition

Represents the amount of expense expected to be recognized during in the remainder of the fiscal year following the latest fiscal year arising from the equity-based compensation arrangements.

+ References

No definition available.

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Represents the amount of total expense expected to be recognized from the equity-based compensation arrangements.

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No definition available.

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Represents the amount of expense expected to be recognized during the third fiscal year following the latest fiscal year arising from the equity-based compensation arrangements.

+ References

No definition available.

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Represents the amount of expense expected to be recognized during the second fiscal year following the latest fiscal year arising from the equity-based compensation arrangements.

+ References

No definition available.

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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

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SAB Topic 14.F)
-URI http://asc.fasb.org/extlink&oid=27013229&loc=d3e301413-122809

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5047-113901

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
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-Section 50
-Paragraph 2
-Subparagraph (h)(1)(i)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

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The number of equity-based payment instruments, excluding stock (or unit) options, that vested during the reporting period.

+ References

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)(2)(iii)(2)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

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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.

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No definition available.

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The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

+ References

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

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