Note 2 - Significant Accounting Policies (Details Textual)	3 Months Ended			6 Months Ended		12 Months Ended
	Sep. 30, 2022 USD ($)	Jun. 30, 2022	Sep. 30, 2021 USD ($)	Sep. 30, 2022 USD ($)	Sep. 30, 2021 USD ($)	Mar. 31, 2022
Contract with Customer, Liability, Revenue Recognized	$ 0		$ 0	$ 91,000	$ 49,000
Customer Concentration Risk [Member] | Revenue Benchmark [Member]
Number of Major Customers	1		2	2	2
Customer Concentration Risk [Member] | Revenue Benchmark [Member] | Customer Number 1 [Member]
Concentration Risk, Percentage	48.00%		28.00%	35.00%	21.00%
Customer Concentration Risk [Member] | Revenue Benchmark [Member] | Customer Number 2 [Member]
Concentration Risk, Percentage			21.00%	10.00%	16.00%
Customer Concentration Risk [Member] | Accounts Receivable [Member]
Number of Major Customers		2				2
Customer Concentration Risk [Member] | Accounts Receivable [Member] | Customer Number 1 [Member]
Concentration Risk, Percentage				76.00%		76.00%
Customer Concentration Risk [Member] | Accounts Receivable [Member] | Customer Number 2 [Member]
Concentration Risk, Percentage				63.00%		63.00%