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ACQUISITIONS AND DROP DOWN TRANSACTIONS - Polar and Divide Drop Down (Details) - Polar Midstream and Epping - USD ($) $ in Thousands	Jul. 31, 2015	May 18, 2015
Business Acquisition [Line Items]
Purchase price		$ 285,677
Liabilities incurred for acquisition		92,000
Cash payment for working capital and capital expenditure adjustments	$ 4,300
Common units
Business Acquisition [Line Items]
Issuance of stock		193,400
General Partner Units
Business Acquisition [Line Items]
Issuance of stock		4,100
Previously Reported
Business Acquisition [Line Items]
Purchase price		$ 290,000