Note 8 - Revenue - Remaining Performance Obligations 2 (Details)	Sep. 30, 2022 USD ($)
Revenue, Remaining Performance Obligation, Amount	$ 4,414,000
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2022-10-01
Revenue, Remaining Performance Obligation, Amount	$ 502,000
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction (Year)	3 months
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2023-01-01
Revenue, Remaining Performance Obligation, Amount	$ 2,121,000
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction (Year)	1 year
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2024-01-01
Revenue, Remaining Performance Obligation, Amount	$ 1,004,000
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction (Year)	1 year
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2025-01-01
Revenue, Remaining Performance Obligation, Amount	$ 475,000
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction (Year)	1 year
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2026-01-01
Revenue, Remaining Performance Obligation, Amount	$ 312,000
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction (Year)	1 year
Service [Member]
Revenue, Remaining Performance Obligation, Amount	$ 2,336,000
Service [Member] | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2022-10-01
Revenue, Remaining Performance Obligation, Amount	$ 407,000
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction (Year)	3 months
Service [Member] | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2023-01-01
Revenue, Remaining Performance Obligation, Amount	$ 1,089,000
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction (Year)	1 year
Service [Member] | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2024-01-01
Revenue, Remaining Performance Obligation, Amount	$ 664,000
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction (Year)	1 year
Service [Member] | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2025-01-01
Revenue, Remaining Performance Obligation, Amount	$ 176,000
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction (Year)	1 year
Device Revenue [Member]
Revenue, Remaining Performance Obligation, Amount	$ 795,000	[1]
Device Revenue [Member] | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2022-10-01
Revenue, Remaining Performance Obligation, Amount	$ 21,000	[1]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction (Year)	3 months	[1]
Device Revenue [Member] | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2023-01-01
Revenue, Remaining Performance Obligation, Amount	$ 733,000	[1]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction (Year)	1 year	[1]
Device Revenue [Member] | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2024-01-01
Revenue, Remaining Performance Obligation, Amount	$ 41,000	[1]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction (Year)	1 year	[1]
Exclusivity Fee [Member]
Revenue, Remaining Performance Obligation, Amount	$ 1,119,000
Exclusivity Fee [Member] | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2022-10-01
Revenue, Remaining Performance Obligation, Amount	$ 71,000
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction (Year)	3 months
Exclusivity Fee [Member] | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2023-01-01
Revenue, Remaining Performance Obligation, Amount	$ 286,000
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction (Year)	1 year
Exclusivity Fee [Member] | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2024-01-01
Revenue, Remaining Performance Obligation, Amount	$ 286,000
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction (Year)	1 year
Exclusivity Fee [Member] | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2025-01-01
Revenue, Remaining Performance Obligation, Amount	$ 286,000
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction (Year)	1 year
Exclusivity Fee [Member] | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2026-01-01
Revenue, Remaining Performance Obligation, Amount	$ 190,000
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction (Year)	1 year
Product and Service, Other [Member]
Revenue, Remaining Performance Obligation, Amount	$ 164,000
Product and Service, Other [Member] | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2022-10-01
Revenue, Remaining Performance Obligation, Amount	$ 3,000
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction (Year)	3 months
Product and Service, Other [Member] | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2023-01-01
Revenue, Remaining Performance Obligation, Amount	$ 13,000
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction (Year)	1 year
Product and Service, Other [Member] | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2024-01-01
Revenue, Remaining Performance Obligation, Amount	$ 13,000
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction (Year)	1 year
Product and Service, Other [Member] | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2025-01-01
Revenue, Remaining Performance Obligation, Amount	$ 13,000
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction (Year)	1 year
Product and Service, Other [Member] | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2026-01-01
Revenue, Remaining Performance Obligation, Amount	$ 122,000
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction (Year)	1 year

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