Note 3 - Related-party Transactions - Consolidated Statements of Operations (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2025	Jun. 30, 2024	Jun. 30, 2025	Jun. 30, 2024
Revenue from operations	$ 56,583	$ 69,659	$ 140,275	$ 160,681
Percentage of revenues from operations	100.00%	100.00%	100.00%	100.00%
Lazarus Energy Holdings (LEH) [Member] | Refinery Operations [Member]
Revenue from operations	$ 24,121	$ 26,026	$ 49,069	$ 53,420
Percentage of revenues from operations	42.60%	37.40%	35.00%	33.20%
Lazarus Energy Holdings (LEH) [Member] | Tolling and Terminaling [Member]
Revenue from operations	$ 540	$ 540	$ 1,080	$ 1,080
Percentage of revenues from operations	1.00%	0.80%	0.80%	0.70%
Related Party [Member]
Interest expense, related party	$ 340	$ 303	$ 634	$ 608
Related Party [Member] | Jonathan Carroll [Member] | LE Term Loan Due 2034 [Member]
Interest expense, related party	92	97	185	195
Related Party [Member] | Jonathan Carroll [Member] | NPS Term Loan Due 2031 [Member]
Interest expense, related party	47	50	93	100
Related Party [Member] | Jonathan Carroll [Member] | LRM Term Loan Due 2034 [Member]
Interest expense, related party	38	40	77	81
Related Party [Member] | Jonathan Carroll [Member] | BDEC Term Loan Due 2051 [Member]
Interest expense, related party	10	10	20	20
Related Party [Member] | Lazarus Energy Holdings (LEH) [Member] | BDPL-LEH Loan Agreement [Member]
Interest expense, related party	153	106	259	212
Nonrelated Party [Member] | Refinery Operations [Member]
Revenue from operations	$ 31,674	$ 42,522	$ 89,594	$ 105,043
Percentage of revenues from operations	56.00%	61.00%	63.90%	65.40%
Nonrelated Party [Member] | Tolling and Terminaling [Member]
Revenue from operations	$ 248	$ 571	$ 532	$ 1,138
Percentage of revenues from operations	0.40%	0.80%	0.40%	0.70%