Note 8 - Revenue - Remaining Performance Obligations (Details)	Jun. 30, 2022 USD ($)
Revenue, Remaining Performance Obligation, Amount	$ 3,933,000
Service [Member]
Revenue, Remaining Performance Obligation, Amount	1,750,000
Device Revenue [Member]
Revenue, Remaining Performance Obligation, Amount	815,000	[1]
Exclusivity Fee [Member]
Revenue, Remaining Performance Obligation, Amount	1,192,000
Product and Service, Other [Member]
Revenue, Remaining Performance Obligation, Amount	$ 176,000

[1] Represents the minimum purchase requirements under the distribution agreement the Company signed with its AXP distributor in China.