Condensed Consolidated Statements of Income - USD ($)	3 Months Ended		9 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2020	Dec. 31, 2019
Condensed Consolidated Statements of Income [Abstract]
Net sales	$ 122,568,000	$ 125,574,000	$ 372,654,000	$ 385,096,000
Cost of goods sold	98,327,000	97,913,000	295,300,000	303,279,000
Gross profit	24,241,000	27,661,000	77,354,000	81,817,000
Operating expenses:
General and administrative	14,005,000	14,390,000	38,210,000	39,410,000
Sales and marketing	4,698,000	5,623,000	13,224,000	15,990,000
Research and development	2,100,000	2,174,000	6,014,000	6,694,000
Foreign exchange impact of lease liabilities and forward contracts	(12,455,000)	(3,772,000)	(21,257,000)	(2,507,000)
Total operating expenses	8,348,000	18,415,000	36,191,000	59,587,000
Operating income	15,893,000	9,246,000	41,163,000	22,230,000
Interest expense, net	4,051,000	6,879,000	12,074,000	19,575,000
Income before income tax expense	11,842,000	2,367,000	29,089,000	2,655,000
Income tax expense	3,373,000	1,502,000	8,448,000	1,752,000
Net income	$ 8,469,000	$ 865,000	$ 20,641,000	$ 903,000
Basic net income per share (in dollars per share)	$ 0.44	$ 0.05	$ 1.09	$ 0.05
Diluted net income per share (in dollars per share)	$ 0.44	$ 0.04	$ 1.07	$ 0.05
Weighted average number of shares outstanding:
Basic (in shares)	19,053,232	18,961,517	19,016,302	18,895,893
Diluted (in shares)	19,436,793	19,305,805	19,333,758	19,263,114