Note 3 - Revenue Recognition - Revenue by Major Product Category (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Total Revenue	$ 76,608	$ 46,084	$ 182,298	$ 142,214
Percent of Revenue	100.00%	100.00%	100.00%	100.00%
Data Center [Member]
Total Revenue	$ 55,336	$ 34,006	$ 141,133	$ 104,311
Percent of Revenue	72.20%	73.80%	77.40%	73.30%
CATV [Member]
Total Revenue	$ 11,642	$ 8,797	$ 22,007	$ 30,577
Percent of Revenue	15.20%	19.10%	12.10%	21.50%
Telecom [Member]
Total Revenue	$ 8,870	$ 2,868	$ 17,600	$ 6,236
Percent of Revenue	11.60%	6.20%	9.70%	4.40%
FTTH [Member]
Total Revenue	$ 67	$ 39	$ 69	$ 149
Percent of Revenue	0.10%	0.10%	0.00%	0.10%
Product and Service, Other [Member]
Total Revenue	$ 693	$ 374	$ 1,489	$ 941
Percent of Revenue	0.90%	0.80%	0.80%	0.70%