Note D - Inventories - Summary of Inventory Values by Product Group (Details) - USD ($)	Dec. 31, 2018	Mar. 31, 2018
Inventories	$ 59,415,035	$ 45,329,434
Prime Coil Inventory [Member]
Raw materials	32,052,655	14,185,858
Non-standard Coil Inventory [Member]
Raw materials	2,353,592	2,971,324
Tubular Inventory [Member]
Raw materials	8,127,972	6,734,076
Finished goods	$ 16,880,816	$ 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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