Oil and Natural Gas Properties Acquisitions - Canaan Farmout (Details) - Angelina County, Texas - Farmout Agreement $ in Millions		12 Months Ended
	Feb. 21, 2017 well	Dec. 31, 2019 USD ($) well	Dec. 31, 2018 USD ($)
Business Acquisition [Line Items]
Ownership interest, acreage, percent	50.00%
Exploratory wells, expected to be drilled | well	20	17
Exploratory wells, additional wells to be drilled | well	20
Asset acquisition, number of phases	3
Canaan Resource Partners
Business Acquisition [Line Items]
Asset acquisition, term of phase	2 years
Asset acquisition, ownership interest in wells, percent	80.00%
Asset acquisition, funding requirements, drilling and completion costs, percent	80.00%
Asset acquisition, ownership interest, gross, percent	40.00%
Asset acquisition, third phase, ownership interest in additional wells, gross, percent	20.00%
Asset acquisition, third phase, ownership interest In additional wells, percent	40.00%
Asset acquisition, third phase, funding requirements, drilling and completion costs, percent	40.00%
Revenue of acquiree since acquisition date, actual | $		$ 90.0
Canaan Resource Partners | Commodity Derivative Liabilities, Long-term
Business Acquisition [Line Items]
Working interests in wells drilled and completed, actual | $		$ 0.9	$ 11.6