v3.8.0.1

PARTNERS' EQUITY Table 4 - General Partner Incentive Distributions (Details)	12 Months Ended
	Dec. 31, 2017
Common Limited Partner [Member] | Quarterly Distributions Level 1 [Member]
Distribution Allocation [Line Items]
Quarterly distribution amount per common unit	Up to $0.60
Percentage of distribution allocated to common unitholders	98.00%
Common Limited Partner [Member] | Quarterly Distributions Level 2 [Member]
Distribution Allocation [Line Items]
Quarterly distribution amount per common unit	Above $0.60 up to $0.66
Percentage of distribution allocated to common unitholders	90.00%
Common Limited Partner [Member] | Quarterly Distributions Level 3 [Member]
Distribution Allocation [Line Items]
Quarterly distribution amount per common unit	Above $0.66
Percentage of distribution allocated to common unitholders	75.00%
General Partner [Member] | Quarterly Distributions Level 1 [Member]
Distribution Allocation [Line Items]
Percentage of distribution allocated to the general partner	2.00%
General Partner [Member] | Quarterly Distributions Level 2 [Member]
Distribution Allocation [Line Items]
Percentage of distribution allocated to the general partner	10.00%
General Partner [Member] | Quarterly Distributions Level 3 [Member]
Distribution Allocation [Line Items]
Percentage of distribution allocated to the general partner	25.00%

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Distribution Allocation [Line Items]

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Percentage of the total distribution allocated to the general partner, which includes both the general partner interest and the incentive distributions.

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Percentage of the total distribution allocated to the common limited partners.

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Threshold (quarterly distribution amount per limited partner unit) that must be met to receive the corresponding percentage of the total distribution.

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