Other Liabilities - Schedule of Other Liabilities (Long-term) (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Other Liabilities Disclosure [Abstract]
Environmental reserves	$ 7,237	$ 7,266
Supplemental executive retirement plan liability	1,264	1,510
Pension liability	855	941
Other long-term liabilities	3,167	4,656
Other liabilities (long-term), Total	$ 12,523	$ 14,373