Note H - Revenue - Disaggregation of Revenue (Details) - USD ($)	3 Months Ended		9 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2018	Dec. 31, 2017
Net sales	$ 43,326,080	$ 28,033,521	$ 144,951,427	$ 77,194,500
Coil [Member]
Net sales	28,730,992	22,409,571	94,688,636	60,547,245
Coil [Member] | Prime Coil [Member]
Net sales	25,074,965	17,862,981	79,426,810	47,598,283
Coil [Member] | Secondary Coil [Member]
Net sales	3,350,738	4,189,947	14,355,617	12,001,311
Coil [Member] | Customer Owned [Member]
Net sales	305,289	356,643	906,209	947,651
Tubular [Member]
Net sales	14,595,088	5,623,950	50,262,791	16,647,255
Tubular [Member] | Manufactured Pipe [Member]
Net sales	10,767,166	4,144,506	35,936,762	10,467,228
Tubular [Member] | Mill Reject Pipe [Member]
Net sales	3,761,188	1,479,444	13,489,029	4,515,771
Tubular [Member] | Pipe Finishing Services [Member]
Net sales	$ 66,734		$ 837,000	$ 1,664,256