Debt - Debt Summary (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
	Mar. 31, 2017	Mar. 31, 2018	Mar. 31, 2017	Dec. 31, 2016	May 05, 2010
Debt Instrument [Line Items]
Revolving line of credit	$ 33,881	$ 0	$ 33,881
Total debt	388,211	324,623	388,211
Current maturities	(2,000)	(20,540)	(2,000)
Total long-term debt	386,211	304,083	386,211
Term Loan Credit Agreement
Debt Instrument [Line Items]
Long-term debt	0	318,782	0
Amortization of financing and debt discount		13,300	0
10.5% Senior Notes, net
Debt Instrument [Line Items]
Long-term debt	352,472	0	352,472
Amortization of financing and debt discount	500	$ 0
Stated interest rate (as a percent)		10.50%		10.50%	10.50%
Revolving line of credit
Debt Instrument [Line Items]
Revolving line of credit	33,881	$ 0	33,881
Other, net
Debt Instrument [Line Items]
Long-term debt	$ 1,858	5,841	1,858
Amortization of financing and debt discount		$ 500	$ (500)