Long-Term Debt (Details) - USD ($) $ in Thousands	Mar. 31, 2017	Dec. 31, 2016
Senior debt:
Total debt	$ 472,453	$ 450,450
Less: Debt issuance costs	(5,130)	(4,861)
Total debt, net of debt issuance costs	467,323	445,589
Less: Current maturities	(467,323)	(445,589)
Long-term debt, net of current maturities	0	0
Revolving credit facility
Senior debt:
Total debt	198,453	172,700
Term loans [Member]
Senior debt:
Total debt	$ 274,000	$ 277,750