PARTNERS' CAPITAL AND DISTRIBUTIONS - Summary of Changes in Outstanding Units (Details) - Limited Partner - shares shares in Thousands		9 Months Ended
Sep. 21, 2017	Sep. 30, 2017
Summary of Changes in Outstanding Units for the Period
Beginning Balance (in shares)		140,264
Ending Balance (in shares)		146,642
Equity Distribution Agreements
Summary of Changes in Outstanding Units for the Period
Issuance of units through Equity Distribution Agreements (in shares)	3,800	6,159
Option Plan
Summary of Changes in Outstanding Units for the Period
LP Units issued (in shares)		10
Long Term Incentive Plan 2013
Summary of Changes in Outstanding Units for the Period
LP Units issued (in shares)		209

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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- Definition

The number of each class of partnership units outstanding at the balance sheet date. Units represent shares of ownership of the general, limited, and preferred partners.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 946
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.6-04.16(b))
-URI http://asc.fasb.org/extlink&oid=6488278&loc=d3e603758-122996

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
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-Section S99
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-URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187171-122770

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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.3-04)
-URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187085-122770

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-Publisher FASB
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-Section 50
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- Definition

The number of units issued due to unit-based compensation.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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