Note 11 - CUSTOMER AND GEOGRAPHIC INFORMATION - Revenues by Geographic Area (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Revenues	$ 29,555	$ 23,112	$ 81,174	$ 65,678
Geographic Concentration Risk [Member] | Revenue Benchmark [Member]
Revenues	$ 29,555	$ 23,112	$ 81,174	$ 65,678
Concentration risk	100.00%	100.00%	100.00%	100.00%
Geographic Concentration Risk [Member] | Revenue Benchmark [Member] | UNITED STATES
Revenues	$ 13,983	$ 7,710	$ 34,634	$ 26,242
Concentration risk	47.00%	33.00%	43.00%	40.00%
Geographic Concentration Risk [Member] | Revenue Benchmark [Member] | CHINA
Revenues	$ 4,038	$ 6,747	$ 10,065	$ 10,200
Concentration risk	14.00%	29.00%	12.00%	16.00%
Geographic Concentration Risk [Member] | Revenue Benchmark [Member] | JAPAN
Revenues			$ 8,543	$ 3,414
Concentration risk			10.00%	5.00%
Geographic Concentration Risk [Member] | Revenue Benchmark [Member] | TAIWAN, PROVINCE OF CHINA
Revenues			$ 5,411	$ 8,038
Concentration risk			7.00%	12.00%
Geographic Concentration Risk [Member] | Revenue Benchmark [Member] | Rest of the World [Member]
Revenues	$ 11,534	$ 8,655	$ 22,521	$ 17,784
Concentration risk	39.00%	38.00%	28.00%	27.00%