Note 4 - BALANCE SHEET COMPONENTS - Other (Details) - USD ($)	3 Months Ended			6 Months Ended
	Jun. 30, 2022	Dec. 31, 2021	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021
Unbilled Receivables, Current	$ 8,900,000	$ 11,800,000		$ 8,900,000
Unbilled Receivables, Not Expected to be Billed and Collected in Next Twelve Months	1,100,000	1,300,000		1,100,000
Depreciation, Depletion and Amortization, Nonproduction, Total	1,400,000		$ 1,600,000	2,800,000	$ 3,300,000
Impairment of Intangible Assets, Finite-lived	0		0	0	0
Goodwill	14,123,000	14,123,000		14,123,000
Impairment of goodwill	0		0	0	0
Amortization of Intangible Assets, Total	867,000		849,000	$ 1,734,000	1,698,000
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life (Year)				6 years 7 months 6 days
Write-down in value of property and equipment		3,200,000
Cost of Sales [Member]
Amortization of Intangible Assets, Total	553,000		536,000	$ 1,106,000	1,071,000
Costs and Expenses [Member]
Amortization of Intangible Assets, Total	314,000		$ 313,000	628,000	$ 627,000
DFI Test Equipment [Member]
Construction in Progress, Gross	$ 19,800,000	$ 20,000,000.0		$ 19,800,000