SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Oil and Natural Gas Properties, Other Property, Equipment and Land (Details)	12 Months Ended
	Dec. 31, 2019 USD ($) $ / Boe	Dec. 31, 2018 USD ($) $ / Boe	Dec. 31, 2017 USD ($) $ / Boe
Property, Plant and Equipment [Line Items]
Depreciation, depletion and amortization excluding amortization of financing costs	$ 1,447,000,000	$ 623,000,000	$ 327,000,000
Estimated future net revenue discounted rate per annum	10.00%
Impairment of oil and natural gas properties	$ 790,000,000	$ 0	$ 0
Oil and Gas Properties
Property, Plant and Equipment [Line Items]
Average depletion rate per barrel equivalent unit of production | $ / Boe	13.54	12.62	11.11
Depreciation, depletion and amortization excluding amortization of financing costs	$ 1,400,000,000	$ 595,000,000	$ 321,000,000
Other Property and Equipment, Net
Property, Plant and Equipment [Line Items]
Depreciation, depletion and amortization excluding amortization of financing costs	$ 16,000,000	$ 9,000,000	$ 1,000,000
Other Property and Equipment, Net | Minimum
Property, Plant and Equipment [Line Items]
Estimated useful life of property and equipment	3 years
Other Property and Equipment, Net | Maximum
Property, Plant and Equipment [Line Items]
Estimated useful life of property and equipment	15 years