Note 8 - Concentration Risk (Details Textual)	3 Months Ended		6 Months Ended		12 Months Ended
	Sep. 30, 2023 USD ($)	Sep. 30, 2022	Sep. 30, 2023 USD ($)	Sep. 30, 2022	Mar. 31, 2023 USD ($)
Cash, Uninsured Amount	$ 20,600,000		$ 20,600,000		$ 25,000,000
Maximum [Member]
Cash, FDIC Insured Amount	$ 250,000		$ 250,000
Customer Concentration Risk [Member] | Revenue Benchmark [Member]
Number of Customers	3	3	3
Customer Concentration Risk [Member] | Revenue Benchmark [Member] | Three Largest Customers [Member]
Concentration Risk, Percentage	90.00%	90.00%	89.00%	83.00%
Customer Concentration Risk [Member] | Revenue Benchmark [Member] | Walmart [Member]
Concentration Risk, Percentage	60.00%	48.00%	53.00%	45.00%
Customer Concentration Risk [Member] | Revenue Benchmark [Member] | Amazon [Member]
Concentration Risk, Percentage	19.00%	24.00%	22.00%	22.00%
Customer Concentration Risk [Member] | Revenue Benchmark [Member] | Fred Meyer [Member]
Concentration Risk, Percentage	11.00%	18.00%	14.00%	16.00%
Customer Concentration Risk [Member] | Accounts Receivable [Member]
Number of Customers			3		3
Customer Concentration Risk [Member] | Accounts Receivable [Member] | Customer One [Member]
Concentration Risk, Percentage			54.00%		43.00%
Customer Concentration Risk [Member] | Accounts Receivable [Member] | Customer Two [Member]
Concentration Risk, Percentage			28.00%		35.00%
Customer Concentration Risk [Member] | Accounts Receivable [Member] | Customer Three [Member]
Concentration Risk, Percentage			10.00%		11.00%
Product Concentration Risk [Member] | Revenue Benchmark [Member] | Microwave Ovens [Member]
Concentration Risk, Percentage	27.00%	29.00%	32.00%	34.00%
Product Concentration Risk [Member] | Revenue Benchmark [Member] | Audio Products [Member]
Concentration Risk, Percentage	70.00%	70.00%	66.00%	65.00%
Supplier Concentration Risk [Member] | Products for Resale [Member]
Number of Factory Suppliers	3	2	3	2
Supplier Concentration Risk [Member] | Products for Resale [Member] | Three Largest Factory Suppliers [Member]
Concentration Risk, Percentage	80.00%		80.00%
Supplier Concentration Risk [Member] | Products for Resale [Member] | Largest Supplier [Member]
Concentration Risk, Percentage	34.00%	64.00%	39.00%	70.00%
Supplier Concentration Risk [Member] | Products for Resale [Member] | Supplier One [Member]
Concentration Risk, Percentage	31.00%	36.00%	24.00%	30.00%
Supplier Concentration Risk [Member] | Products for Resale [Member] | Supplier Two [Member]
Concentration Risk, Percentage	15.00%		17.00%
Supplier Concentration Risk [Member] | Products for Resale [Member] | Two Largest Factory Suppliers [Member]
Concentration Risk, Percentage		100.00%		100.00%