Consolidated Statements of Operations (Unaudited) - USD ($)	3 Months Ended
	Jun. 30, 2018	Jun. 30, 2017
Consolidated Statements of Operations (Unaudited) [Abstract]
Net sales	$ 92,565,000	$ 95,519,000
Cost of goods sold	75,314,000	68,843,000
Gross profit	17,251,000	26,676,000
Operating expenses:
General and administrative	12,340,000	6,187,000
Sales and marketing	4,392,000	3,394,000
Research and development	1,736,000	1,002,000
Total operating expenses	18,468,000	10,583,000
Operating (loss) income	(1,217,000)	16,093,000
Interest expense, net	5,075,000	3,314,000
(Loss) income before income tax (benefit) expense	(6,292,000)	12,779,000
Income tax (benefit) expense	(1,278,000)	4,628,000
Net (loss) income	$ (5,014,000)	$ 8,151,000
Basic net (loss) income per share (in dollars per share)	$ (0.27)	$ 0.44
Diluted net (loss) income per share (in dollars per share)	$ (0.27)	$ 0.42
Weighted average number of shares outstanding:
Basic (in shares)	18,895,847	18,655,304
Diluted (in shares)	18,895,847	19,421,352