Revenue Concentrations, Significant Customers, and Geographic Areas (Summary Of Revenue By Product Line) (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Concentration Risk [Line Items]
Revenues	$ 16,683	$ 11,828	$ 46,657	$ 40,157
High precision 3D and 2D sensors [Member]
Concentration Risk [Line Items]
Revenues	5,388	4,030	15,696	13,569
Semiconductor sensors [Member]
Concentration Risk [Line Items]
Revenues	3,463	2,228	10,564	7,698
Inspection and Metrology Systems [Member]
Concentration Risk [Line Items]
Revenues	$ 7,832	$ 5,570	$ 20,397	$ 18,890