Note 3 - Related-party Transactions - Consolidated Statements of Operations (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Revenue	$ 396,048	$ 487,504
Tied to First Term Loan Due 2034	6,103	5,885
Tolling and Terminaling [Member]
Revenue	$ 396,048	$ 487,504
Percentage of revenues from operations	100.00%	100.00%
Lazarus Energy Holdings (LEH) [Member] \| Refinery Operations [Member]
Revenue	$ 123,395	$ 173,646
Percentage of revenues from operations	31.20%	35.60%
Lazarus Energy Holdings (LEH) [Member] \| Tolling and Terminaling [Member]
Revenue	$ 2,160	$ 360
Percentage of revenues from operations	0.50%	0.10%
Related Party [Member]
Tied to First Term Loan Due 2034	$ 1,467	$ 1,683
Related Party [Member] \| Jonathan Carroll [Member] \| LE Term Loan Due 2034 [Member]
Tied to First Term Loan Due 2034	403	428
Related Party [Member] \| Jonathan Carroll [Member] \| LRM Term Loan Due 2034 [Member]
Tied to First Term Loan Due 2034	167	177
Related Party [Member] \| Jonathan Carroll [Member] \| BDEC Term Loan Due 2051 [Member]
Tied to First Term Loan Due 2034	40	0
Related Party [Member] \| Jonathan Carroll [Member] \| NPS Term Loan Due 2031 [Member]
Tied to First Term Loan Due 2034	200	0
Related Party [Member] \| Lazarus Energy Holdings (LEH) [Member] \| BDPL-LEH Loan Agreement [Member]
Tied to First Term Loan Due 2034	657	480
Related Party [Member] \| Lazarus Energy Holdings (LEH) [Member] \| June LEH Note [Member]
Tied to First Term Loan Due 2034	0	598
Nonrelated Party [Member] \| Refinery Operations [Member]
Revenue	$ 266,621	$ 309,415
Percentage of revenues from operations	67.30%	63.50%
Nonrelated Party [Member] \| Tolling and Terminaling [Member]
Revenue	$ 3,872	$ 4,083
Percentage of revenues from operations	1.00%	0.80%