EQUITY METHOD INVESTMENTS - Schedule of Equity Method Investments (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018		Dec. 31, 2017		Dec. 20, 2019	Oct. 01, 2019	Feb. 15, 2019	Feb. 01, 2019
Schedule of Equity Method Investments [Line Items]
Equity method investments	$ 479,558	$ 0	[1]
Income (loss) of equity method investees	$ (6,329)	0	[1]	$ 1,366	[1]
EPIC Crude Holdings, LP
Schedule of Equity Method Investments [Line Items]
Ownership Interest	10.00%								10.00%
Equity method investments	$ 109,806	0
Income (loss) of equity method investees	$ (6,597)	0		0
Gray Oak Pipeline, LLC
Schedule of Equity Method Investments [Line Items]
Ownership Interest	10.00%							10.00%
Equity method investments	$ 115,840	0
Income (loss) of equity method investees	$ 831	0		0
Wink to Webster Pipeline LLC
Schedule of Equity Method Investments [Line Items]
Ownership Interest	4.00%
Equity method investments	$ 34,124	0
Income (loss) of equity method investees	$ (539)	0		0
OMOG JV LLC
Schedule of Equity Method Investments [Line Items]
Ownership Interest	60.00%						60.00%
Equity method investments	$ 219,098	0
Income (loss) of equity method investees	$ (24)	0		0
Amarillo Rattler, LLC
Schedule of Equity Method Investments [Line Items]
Ownership Interest	50.00%					50.00%
Equity method investments	$ 690	0
HMW LLC
Schedule of Equity Method Investments [Line Items]
Income (loss) of equity method investees	$ 0	$ 0		$ 1,366

[1] See Note 1 for information regarding the basis of financial statement presentation.