Segment Reporting - Identifiable Assets by Industry Segment (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Segment Reporting Information [Line Items]
Total assets	$ 361,334	$ 384,159	$ 374,703
Operating Segments | Marketing
Segment Reporting Information [Line Items]
Total assets	185,285	215,813	162,770
Operating Segments | Trans-portation
Segment Reporting Information [Line Items]
Total assets	57,653	60,405	67,167
Operating Segments | Pipeline and storage
Segment Reporting Information [Line Items]
Total assets	25,027	25,815	25,569
Operating Segments | Logistics and repurposing
Segment Reporting Information [Line Items]
Total assets	43,258	45,307	0
Cash and other
Segment Reporting Information [Line Items]
Total assets	$ 50,111	$ 36,819	$ 119,197