Income Taxes - Schedule of Deferred Tax Assets and Liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018	Jul. 31, 2018
Deferred Tax Assets, Gross [Abstract]
Investment in subsidiary	$ 19,021	$ 0
Total deferred tax assets:	19,021	0
Deferred tax liabilities:
Oil and gas properties	(198)	(208)
Investment in subsidiary	0	(3,476)
Net noncurrent deferred tax liabilities	$ (198)	$ (3,684)	$ (3,100)