Amount, including tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value-added and excise.

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+ Details

REVENUE RECOGNITION - Disaggregation of Revenue (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Disaggregation of Revenue [Line Items]
Midstream services revenue - affiliate	$ 31,616	$ 24,139	$ 72,383	$ 57,985
Gas gathering and compression
Disaggregation of Revenue [Line Items]
Midstream services revenue - affiliate	4,394	2,697	10,114	6,310
Gas processing
Disaggregation of Revenue [Line Items]
Midstream services revenue - affiliate	23,184	18,395	53,080	43,679
Transmission
Disaggregation of Revenue [Line Items]
Midstream services revenue - affiliate	3,226	2,977	7,401	7,831
NGL transmission
Disaggregation of Revenue [Line Items]
Midstream services revenue - affiliate	587	$ 70	1,413	165
Other
Disaggregation of Revenue [Line Items]
Midstream services revenue - affiliate	$ 225		$ 375	$ 0