INCOME TAXES - EFFECTIVE TAX RATE RECONCILIATION (Details)	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Income Tax Disclosure [Abstract]
U.S. federal statutory tax rate	21.00%	21.00%	35.00%
Enhanced oil recovery credit and other general business credits	(4.00%)	(3.00%)	(9.00%)
Change in federal income tax rate	0.00%	0.00%	(44.00%)
Tax (benefit) expense due to reversal of indefinite reinvestment assertion	0.00%	(2.00%)	7.00%
Tax impact from foreign operations	187.00%	11.00%	12.00%
State income taxes, net of federal benefit	28.00%	1.00%	2.00%
Uncertain tax positions	13.00%	0.00%	0.00%
Transaction costs	19.00%	0.00%	0.00%
Non-controlling interest	(16.00%)	0.00%	0.00%
Executive compensation limitation	24.00%	0.00%	0.00%
Stock warrants	(9.00%)	0.00%	0.00%
WES loss of control	113.00%	0.00%	0.00%
Other	(3.00%)	(2.00%)	(2.00%)
Worldwide effective tax rate	373.00%	26.00%	1.00%

Effective Income Tax Rate Reconciliation, Business Acquisition, Transaction Costs, Percent

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Effective Income Tax Rate Reconciliation, Loss of Control in Equity Method Investment, Percent

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Percentage of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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Percentage of domestic federal statutory tax rate applicable to pretax income (loss).

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