Income Taxes - Income Tax Expense (Benefit) (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
Successor [Member]
Income Tax Examination [Line Items]
Income tax provision (benefit) at statutory rate	$ 18,378
Percentage depletion allowance	(7,039)
State taxes, net of effect of federal taxes	483
Change in valuation allowance	(11,902)
Other, net	920
Income Tax Expense (Benefit)	$ 840
Predecessor [Member]
Income Tax Examination [Line Items]
Income tax provision (benefit) at statutory rate		$ (72,735)
Percentage depletion allowance		(25,667)
State taxes, net of effect of federal taxes		(4,490)
Change in valuation allowance		100,562
Other, net		1,219
Income Tax Expense (Benefit)		$ (1,111)