DERIVATIVE INSTRUMENTS AND PRICE RISK MANAGEMENT - Weighted Average Price of Open Commodity Derivative Contracts (Details) Mcf in Millions	3 Months Ended
	Mar. 31, 2020 $ / bbl Mcf bbl
2020
Derivative [Line Items]
Volume (in barrels) | bbl	7,441,988
Weighted average price (in dollars per barrel)	58.05
2021
Derivative [Line Items]
Volume (in barrels) | bbl	6,333,674
Weighted average price (in dollars per barrel)	55.41
Notional amount covered by options (in shares) | Mcf	0.3
Weighted average price if options are exercised (in dollars per barrel)	57.84
2022
Derivative [Line Items]
Volume (in barrels) | bbl	1,372,866
Weighted average price (in dollars per barrel)	52.57
Notional amount covered by options (in shares) | bbl	2,600,000
Weighted average price if options are exercised (in dollars per barrel)	54.20
2023
Derivative [Line Items]
Notional amount covered by options (in shares) | bbl	200,000
Weighted average price if options are exercised (in dollars per barrel)	43.00