Amount of allowance for credit loss on accounts receivable, classified as current.

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The amount of expense recognized in the current period that reflects the allocation of the cost of tangible assets over the assets' useful lives. Includes production and non-production related depreciation.

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Note 4 - Balance Sheet Components (Details Textual) - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019	Dec. 31, 2019
Accounts Receivable, Allowance for Credit Loss, Current	$ 0		$ 0		$ 0
Depreciation, Total	34,000	$ 131,000	78,000	$ 386,000
Impairment of Property and Equipment			0	0
Amortization of Intangible Assets, Total	$ 433,000	$ 433,000	$ 1,299,000	$ 1,887,000
Intellectual Property [Member]
Finite-Lived Intangible Asset, Useful Life (Year)			20 years
Finite-Lived Intangible Asset, Remaining Life (Year)			7 years 91 days
Developed Technology Rights [Member]
Finite-Lived Intangible Asset, Remaining Life (Year)			9 years 36 days
Minimum [Member]
Finite-Lived Intangible Asset, Useful Life (Year)			1 year 109 days
Maximum [Member]
Finite-Lived Intangible Asset, Useful Life (Year)			11 years 273 days