PARTNERS' EQUITY Table 1 - Cash Distributions - Preferred Units (Details) $ / shares in Units, $ in Thousands	3 Months Ended
Mar. 31, 2021 USD ($) $ / shares
Series A Preferred Limited Partner [Member]
Distribution Made to Preferred Limited Partner [Line Items]
Preferred units distribution percentage, per annum	8.50%
Preferred unit distribution \| $ / shares	$ 0.53125
Fixed distribution per quarter \| $	$ 4,813
Series B Preferred Limited Partner [Member]
Distribution Made to Preferred Limited Partner [Line Items]
Preferred units distribution percentage, per annum	7.625%
Preferred unit distribution \| $ / shares	$ 0.47657
Fixed distribution per quarter \| $	$ 7,339
Series C Preferred Limited Partner [Member]
Distribution Made to Preferred Limited Partner [Line Items]
Preferred units distribution percentage, per annum	9.00%
Preferred unit distribution \| $ / shares	$ 0.56250
Fixed distribution per quarter \| $	$ 3,881

Per unit of ownership amount of cash distributions declared to unit-holder of a limited partnership (LP).

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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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Total distributions to each class of partners (i.e., general, limited and preferred partners).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-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=120397183&loc=d3e187085-122770

Reference 2: 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)
-URI http://asc.fasb.org/extlink&oid=120397183&loc=d3e187171-122770

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The percentage rate used to calculate dividend payments on preferred stock.

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