Note 12 - Segment Reporting - Disaggregation of Revenue (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Revenue	$ 125,342	$ 107,504	$ 364,516	$ 329,187
Injection Molding (Protomold) [Member]
Revenue	57,685	53,257	172,212	165,927
CNC Machining (Firstcut) [Member]
Revenue	43,658	33,115	121,953	99,760
3D Printing (Fineline) [Member]
Revenue	18,589	16,294	53,994	46,478
Sheet Metal [Member]
Revenue	4,854	3,988	14,790	14,306
Other Products [Member]
Revenue	$ 556	$ 850	$ 1,567	$ 2,716