Note H - Derivative Financial Instruments (Details Textual)	6 Months Ended
	Sep. 30, 2022 USD ($) T	Sep. 30, 2021 USD ($)	Mar. 31, 2022 USD ($)
Derivative Asset, Total	$ 743,380		$ 933,200
Derivative Instruments, Gain (Loss) Reclassification from Accumulated OCI to Income, Estimated Net Amount to be Transferred	1,999,420
Derivative Liability, Subject to Master Netting Arrangement, Collateral, Right to Reclaim Cash Not Offset	2,228,051	$ 13,523,416
Other Current Assets [Member]
Derivative Liability, Subject to Master Netting Arrangement, Collateral, Right to Reclaim Cash Not Offset	2,228,051		$ 13,523,416
Accumulated Gain (Loss), Net, Cash Flow Hedge, Parent [Member]
Reclassification from AOCI, Current Period, Tax, Total	$ 511,356	$ 1,819,688
Designated as Hedging Instrument [Member]
Derivative, Nonmonetary Notional Amount, Mass (US Ton) | T	0
Not Designated as Hedging Instrument [Member] | Long [Member]
Derivative, Nonmonetary Notional Amount, Mass (US Ton) | T	5,160
Not Designated as Hedging Instrument [Member] | Short [Member]
Derivative, Nonmonetary Notional Amount, Mass (US Ton) | T	41,460