Long-term Debt - Obligations (Details) - USD ($) $ in Thousands	Mar. 31, 2016	Dec. 31, 2015
Obligations
Total debt	$ (181,343)	$ (182,992)
Current portion of long-term debt and lease obligations	(32,933)	(7,912)
Non-current portion of long-term debt and lease obligations	148,410	175,080
Senior secured second-priority notes [Member]
Obligations
Total debt	(175,000)	(175,000)
Equipment capital leases [Member]
Obligations
Total debt	(8,075)	(9,762)
Revolving credit facility [Member]
Obligations
Total debt	(2,978)	(3,328)
Other debt [Member]
Obligations
Total debt	$ (1,246)	$ (1,558)