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Subsequent Events (Details) - LTIP - Phantom units			1 Months Ended	12 Months Ended
	Jan. 16, 2019 shares	Apr. 02, 2018	Jan. 31, 2019 director	Dec. 31, 2018 shares
Subsequent Events
Units granted under LTIP				1,136,447
Percentage of awards vesting		100.00%
Subsequent Event
Subsequent Events
Units granted under LTIP	15,150
Number of independent directors | director			2
Subsequent Event | Vesting on December 5, 2021
Subsequent Events
Percentage of awards vesting	60.00%
Subsequent Event | Vesting on December 5, 2023
Subsequent Events
Percentage of awards vesting	40.00%

X

- Definition

The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(2)(iii)(1)
-URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5070-113901

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X

- Definition

Percentage of vesting of share-based compensation awards.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5070-113901

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X

- Definition

Detail information of subsequent event by type. User is expected to use existing line items from elsewhere in the taxonomy as the primary line items for this disclosure, which is further associated with dimension and member elements pertaining to a subsequent event.

+ References

No definition available.

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- Definition

The number of independent directors.

+ References

No definition available.

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