Note D - Inventories - Summary of Inventory Values by Product Group (Details) - USD ($)	Jun. 30, 2018	Mar. 31, 2018
Inventories	$ 59,598,607	$ 45,329,434
Prime Coil Inventory [Member]
Raw materials	24,679,720	14,185,858
Non-standard Coil Inventory [Member]
Raw materials	4,727,898	2,971,324
Tubular Inventory [Member]
Raw materials	12,178,658	6,734,076
Finished goods	$ 18,012,331	$ 21,438,176

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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