Note H - Derivative Financial Instruments (Details Textual)	3 Months Ended
Jun. 30, 2021 USD ($) T	Mar. 31, 2021 USD ($)
Derivative Instruments, Gain (Loss) Reclassification from Accumulated OCI to Income, Estimated Net Amount to be Transferred	$ 31,544,060
Accumulated Gain (Loss), Net, Cash Flow Hedge, Parent [Member]
Reclassification from AOCI, Current Period, Tax, Total	849,422
Closed Hedges with Hedged Transaction Still Expected to Occur [Member]
Derivative Instruments, Gain (Loss) Reclassification from Accumulated OCI to Income, Estimated Net Amount to be Transferred	8,794,040
Open Hedges Subject To Fair Value Changes [Member]
Derivative Instruments, Gain (Loss) Reclassification from Accumulated OCI to Income, Estimated Net Amount to be Transferred	$ 22,750,020
Designated as Hedging Instrument [Member] \| Long [Member]
Derivative, Nonmonetary Notional Amount, Mass (US Ton) \| T	7,180
Designated as Hedging Instrument [Member] \| Short [Member]
Derivative, Nonmonetary Notional Amount, Mass (US Ton) \| T	38,520
Not Designated as Hedging Instrument [Member] \| Short [Member]
Derivative, Nonmonetary Notional Amount, Mass (US Ton) \| T	5,820
Other Current Assets [Member]
Derivative, Collateral, Right to Reclaim Cash	$ 29,360,060	$ 12,001,485
Commodity Contract [Member] \| Accounts Payable and Accrued Liabilities [Member]
Hedging Liabilities, Current	$ 1,861,920	$ 501,360

Amount of right to receive cash collateral under master netting arrangements that have not been offset against derivative liabilities.

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The estimated value of gains (losses), net anticipated to be transferred in the future from accumulated other comprehensive income into earnings.

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Nominal mass used to calculate payments on a derivative instrument.

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Carrying amount as of the balance sheet date of the liability arising from a financial instrument or a contract used to mitigate a specified risk (hedge), and which are expected to be converted into cash or otherwise disposed of within a year or the normal operating cycle, if longer.

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Amount of tax expense (benefit) of reclassification adjustment from accumulated other comprehensive income (loss).

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