Note 3 - Revenue Recognition 1 (Details Textual) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2026	Mar. 31, 2025	Dec. 31, 2025	Dec. 31, 2024
Increase (Decrease) in Contract with Customer, Liability	$ (344)	$ (31)
Contract with Customer, Liability, Revenue Recognized	345	30
Accounts Receivable, Blenders' Tax Credit	0		$ 0	$ 6,683
Accounts Receivable, Allowance for Credit Loss	44		28	$ 29
Revenue, Remaining Performance Obligation, Amount	28,791
Bill and Hold Arrangements [Member]
Contract with Customer, Liability	5,486		$ 5,106
Chemicals [Member]
Increase (Decrease) in Contract with Customer, Liability	0	0
Warehouse Space [Member]
Short-Term Lease, Cost	$ 170	$ 170

The amount of blenders' tax credit attributable to accounts receivable.

No definition available.

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- Definition

Amount of allowance for credit loss on accounts receivable.

+ References

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-Section 50
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-Topic 944
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- Definition

Amount of obligation to transfer good or service to customer for which consideration has been received or is receivable.

+ References

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-Topic 606
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- Definition

Amount of revenue recognized that was previously included in balance of obligation to transfer good or service to customer for which consideration from customer has been received or is due.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition

Amount of increase (decrease) in obligation to transfer good or service to customer for which consideration has been received or is receivable.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition

Amount of transaction price allocated to performance obligation that has not been recognized as revenue.

+ References

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- Definition

Amount of short-term lease cost, excluding expense for lease with term of one month or less.

+ References

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