Other Long-Term Liabilities (Details) - USD ($) $ in Thousands	Sep. 30, 2019	Dec. 31, 2018
Other Liabilities Disclosure [Abstract]
Deferred income taxes	$ 8,421	$ 5,113
Pension and post retirement liabilities	9,639	9,238
Uncertain tax positions	320	320
Environmental liabilities	1,100	1,100
Deferred gain on sale leaseback transaction	0	15,073
Deferred contract termination fee	8,019	15,371
Interest rate hedge	2,397	1,023
Other liabilities	2,468	2,401
Other long-term liabilities	$ 32,364	$ 49,639