Schedule II - Valuation and Qualifying Accounts (Details) - USD ($)	12 Months Ended
	Mar. 28, 2021	Mar. 29, 2020	Mar. 31, 2019
Allowance for doubtful accounts:
Change in valuation allowances and reserves
Balance, beginning of period	$ 3,288,800	$ 2,137,900	$ 1,094,900
Provision/expense	(971,600)	2,100,400	1,721,200
Write-offs and other adjustments	(733,000)	(949,500)	(678,200)
Balance, end of period	1,584,200	3,288,800	2,137,900
Inventory Reserve:
Change in valuation allowances and reserves
Balance, beginning of period	9,666,100	5,870,600	5,739,700
Provision/expense	146,600	11,801,500	4,863,100
Write-offs and other adjustments	(6,453,600)	(8,006,000)	(4,732,200)
Balance, end of period	3,359,100	9,666,100	5,870,600
Allowance for deferred tax asset:
Change in valuation allowances and reserves
Balance, beginning of period	2,047,300	141,600
Provision/expense	819,500	1,905,700	141,600
Balance, end of period	$ 2,866,800	$ 2,047,300	$ 141,600