Partners' Capital (Schedule of Common Units) (Details) - Common Units [Member]	9 Months Ended
Sep. 30, 2018 shares
Class of Stock [Line Items]
Phantom unit vesting (in shares)	132,503
Common units issued in connection the ATM (in shares)	(17,286,859)
Limited Partners' Capital Account, Units Outstanding	99,667,999

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.

No definition available.

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The number of limited partner units outstanding.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section S99
-Paragraph 5
-Subparagraph (SAB Topic 4.F)
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-Topic 272
-SubTopic 10
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6373374&loc=d3e70434-108055

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- Definition

Total units issued during the year due to the sale of units. All partners include general, limited and preferred partners.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 272
-SubTopic 10
-Section 50
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The number of units issued due to unit-based compensation.

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-SubTopic 10
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