Consolidated Statements of Stockholders' Equity (Parenthetical) - shares	4 Months Ended	8 Months Ended	12 Months Ended
	Apr. 22, 2016	Dec. 31, 2016	Dec. 31, 2017	Dec. 31, 2015
Predecessor [Member]
Stock issued for benefit plans (shares)	0			352,476
Shares issued from stock option exercises	0			0
Purchase of treasury shares (shares)	65,170			70,437
Employee stock purchase plan (shares)	0			87,629
Issuance of restricted stock (shares)	229,690			304,166
Successor [Member]
Stock issued for benefit plans (shares)		0	0
Shares issued from stock option exercises		0	0
Purchase of treasury shares (shares)		22,485	28,279
Employee stock purchase plan (shares)		0	1,403,508
Issuance of restricted stock (shares)		76,058	141,818