Business Segments - Balance Sheet (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Total assets:
Total assets	$ 509,375	$ 598,851
Terminalling and storage
Total assets:
Total assets	171,320	184,537
Specialty products segment
Total assets:
Total assets	72,770	150,175
Sulfur services
Total assets:
Total assets	103,779	110,688
Transportation
Total assets:
Total assets	$ 161,506	$ 153,451