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Amount of consideration transferred, consisting of acquisition-date fair value of assets transferred by the acquirer, liabilities incurred by the acquirer, and equity interest issued by the acquirer.

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Total investments in (A) an entity in which the entity has significant influence, but does not have control, (B) subsidiaries that are not required to be consolidated and are accounted for using the equity and or cost method, and (C) an entity in which the reporting entity shares control of the entity with another party or group. Includes long-term advances receivable from a party that is affiliated with the reporting entity by means of direct or indirect ownership.

+ References

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-SubTopic 10
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Total contributions made by each class of partners (i.e., general, limited and preferred partners).

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

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PARTNERS' CAPITAL - Schedule of Polar and Divide and Red Rock (Details) - USD ($) $ in Thousands			12 Months Ended
	May 18, 2015	Mar. 18, 2014	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Investment [Line Items]
Net investment			$ 0	$ 0
Partners' capital contribution			2,702	4,737	$ 4,235
Partners' capital distribution			(167,504)	(152,074)	(122,224)
Red Rock Gathering Company, LLC
Investment [Line Items]
Purchase price		$ 307,941
Partners' capital distribution		(66,124)
Polar Midstream and Epping
Investment [Line Items]
Purchase price	$ 285,677
Partners' capital contribution	130,367
Summit Investments \| Red Rock Gathering Company, LLC
Investment [Line Items]
Net investment		241,817
Summit Investments \| Polar Midstream and Epping
Investment [Line Items]
Net investment	416,044
General Partner
Investment [Line Items]
Partners' capital contribution			2,702	4,737	4,235
Partners' capital distribution			(11,256)	(9,784)	(4,770)
General Partner \| Red Rock Gathering Company, LLC
Investment [Line Items]
Partners' capital distribution		(1,323)
General Partner \| Polar Midstream and Epping
Investment [Line Items]
Partners' capital contribution	2,607
Limited partners, Common
Investment [Line Items]
Partners' capital distribution			(142,214)	(86,880)	(67,658)
Limited partners, Common \| Red Rock Gathering Company, LLC
Investment [Line Items]
Partners' capital distribution		(37,910)
Limited partners, Common \| Polar Midstream and Epping
Investment [Line Items]
Partners' capital contribution	80,079
Limited partners, Subordinated
Investment [Line Items]
Partners' capital distribution			$ (14,034)	$ (55,410)	$ (49,796)
Limited partners, Subordinated \| Red Rock Gathering Company, LLC
Investment [Line Items]
Partners' capital distribution		$ (26,891)
Limited partners, Subordinated \| Polar Midstream and Epping
Investment [Line Items]
Partners' capital contribution	$ 47,681