Acquisition of the Predecessor - Narrative (Details) - Predecessor - USD ($) $ in Thousands		3 Months Ended
	Nov. 05, 2015	Jun. 30, 2017	Mar. 31, 2017
Business Acquisition [Line Items]
Cash paid	$ 50,830
Net cash paid in acquisition	24,100
Cash acquired from acquisition	$ 26,700
Decrease in fair value of mineral interests		$ 3,500	$ 3,500
Decrease to additional paid in capital		$ 3,500