Note C - Inventories - Summary of Inventory Values by Product Group (Details) - USD ($)	Sep. 30, 2019	Mar. 31, 2019	Mar. 31, 2018
Inventories	$ 36,092,963	$ 49,062,086	$ 49,062,086
Prime Coil Inventory [Member]
Raw materials	17,206,839	26,240,439
Non-standard Coil Inventory [Member]
Raw materials	2,603,190	2,078,008
Tubular Inventory [Member]
Raw materials	4,380,136	4,418,750
Finished goods	$ 11,902,798	$ 16,324,889

Amount before valuation and LIFO reserves of completed merchandise or goods expected to be sold within one year or operating cycle, if longer.

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Amount after valuation and LIFO reserves of inventory expected to be sold, or consumed within one year or operating cycle, if longer.

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