Taxes (Schedule of Components of Income Tax) (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended	12 Months Ended
	Dec. 31, 2016	Oct. 01, 2016	Dec. 31, 2017	Dec. 31, 2015
Deferred:
Provision for (benefit from) income taxes	$ 1,156		$ (35,255)
Successor
Current:
Federal	0		835
State	(252)		31
Total current	(252)		866
Deferred:
Federal	1,352		(36,162)
State	56		41
Total deferred	1,408		(36,121)
Provision for (benefit from) income taxes	$ 1,156		$ (35,255)
Predecessor
Current:
Federal		$ 0		$ 0
State		7		3
Total current		7		3
Deferred:
Federal		(4,720)		(329,393)
State		87		(43,990)
Total deferred		(4,633)		(373,383)
Provision for (benefit from) income taxes		$ (4,626)		$ (373,380)