v3.8.0.1

REVENUE FROM CONTRACTS WITH CUSTOMERS Table 1 - Adoption Impact of ASC 606 (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Revenues	$ 475,881	$ 487,430
Operating income (loss)	98,480	97,139
Net income (loss)	$ 126,133	$ 57,940
Basic net income per common unit	$ 1.15	$ 0.49
Calculated under Revenue Guidance in Effect before Topic 606 [Member] | Revenue Recognition [Member]
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Revenues	$ 481,786
Operating income (loss)	104,385
Net income (loss)	$ 132,038
Basic net income per common unit	$ 1.21
Difference between Revenue Guidance in Effect before and after Topic 606 [Member] | Revenue Recognition [Member]
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Revenues	$ (5,905)
Operating income (loss)	(5,905)
Net income (loss)	$ (5,905)
Basic net income per common unit	$ (0.06)

X

- Definition

The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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-Publisher FASB
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Per unit of ownership amount after tax of income (loss) available to outstanding limited partnership (LP) unit-holder.

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Total revenue from sale of goods and services rendered during the reporting period, in the normal course of business, reduced by sales returns and allowances, and sales discounts.

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