Note H - Derivative Financial Instruments - Loss Recognized in Earnings for Derivative Instruments (Details) - USD ($)	3 Months Ended	6 Months Ended
Sep. 30, 2021	Sep. 30, 2021
Nonoperating Income (Expense) [Member] \| Hot-rolled Coil Steel Contracts [Member]
Hot-rolled coil steel contracts	$ (6,830,780)	$ (8,219,740)

Amount of realized and unrealized loss of derivative instruments not designated or qualifying as hedging instruments.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4C
-Subparagraph (e)
-URI http://asc.fasb.org/extlink&oid=125515794&loc=SL5624171-113959

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4CC
-URI http://asc.fasb.org/extlink&oid=125515794&loc=SL109998890-113959

Name:	us-gaap_DerivativeInstrumentsNotDesignatedAsHedgingInstrumentsLoss
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration