v3.10.0.1

REVENUE FROM CONTRACTS WITH CUSTOMERS Table 1 - Adoption Impact of ASC 606 (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Revenues	$ 486,204	$ 435,488	$ 962,085	$ 922,918
Operating income (loss)	79,838	73,404	178,318	170,543
Net income (loss)	$ 29,399	$ 26,250	$ 155,532	$ 84,190
Basic net income per common unit	$ 0.15	$ 0.05	$ 1.30	$ 0.51
Calculated under Revenue Guidance in Effect before Topic 606 [Member] | Revenue Recognition [Member]
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Revenues	$ 484,646		$ 966,432
Operating income (loss)	78,280		182,665
Net income (loss)	$ 27,841		$ 159,879
Basic net income per common unit	$ 0.13		$ 1.34
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	$ 1,558		$ (4,347)
Operating income (loss)	1,558		(4,347)
Net income (loss)	$ 1,558		$ (4,347)
Basic net income per common unit	$ 0.02		$ (0.04)

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

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