Emergence from Chapter 11 and Fresh Start Accounting - Shares Issued (Details) - shares		12 Months Ended
	Dec. 31, 2016	Dec. 31, 2017	Dec. 31, 2016
Fresh-Start Adjustment [Line Items]
Shares issued, management incentive plan (in shares)		333,484
Common Stock
Fresh-Start Adjustment [Line Items]
Total shares issued (in shares)			26,095,431
Successor | Common Stock
Fresh-Start Adjustment [Line Items]
Shares issued, rights offering (in shares)	10,825,620
Shares issued, stock to predecessor shareholders (in shares)	75,001
Shares issued, management incentive plan (in shares)	269,810
Shares issued, stock to senior note claimants (in shares)	14,925,000
Total shares issued (in shares)	26,095,431