Commitments and Contingencies (Details) - USD ($) $ in Millions			1 Months Ended	3 Months Ended		9 Months Ended
	Feb. 25, 2019	Feb. 17, 2017	Oct. 31, 2019	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Delivery Of Natural Gas And Oil Production To Third Parties
Long-term Purchase Commitment [Line Items]
Volume requirement commitment				$ 536.2		$ 536.2
Payment for volume requirement agreement				12.0	$ 7.0	34.4	$ 19.9
Corporate Joint Venture | San Mateo Midstream
Commitments and Contingencies (Textual) [Abstract]
Contractual obligation				150.7		$ 150.7
Contract agreement term	15 years
Rustler Breaks and Wolf Asset Area | Corporate Joint Venture | San Mateo Midstream
Commitments and Contingencies (Textual) [Abstract]
Term of contractual obligation		15 years
Rustler Breaks Asset Area | Corporate Joint Venture | San Mateo Midstream
Commitments and Contingencies (Textual) [Abstract]
Term of contractual obligation		15 years
Natural Gas Transportation and Fractionation Agreement | Eddy County
Commitments and Contingencies (Textual) [Abstract]
Agreement term						7 years
2019 15-Year Fixed Fee Natural Gas Transportation Agreement | Eddy County
Commitments and Contingencies (Textual) [Abstract]
Agreement term			15 years
Contractual obligation			$ 106.9
Operational Agreements | San Mateo Midstream
Commitments and Contingencies (Textual) [Abstract]
Contractual obligation				355.3		$ 355.3
Engineering, Procurement, Construction And Installation Of Processing Plant | San Mateo Midstream
Commitments and Contingencies (Textual) [Abstract]
Contractual obligation				81.0		81.0
Payments made under agreement				6.8		40.5
Remaining obligation				$ 0.4		$ 0.4