Note 20 - Reportable Segments (Details Textual)	12 Months Ended
	Dec. 31, 2016
Operating Segments [Member] | Sales Revenue, Net [Member] | Customer Concentration Risk [Member] | Display Technologies [Member]
Number of Customers Individually Accounting for 10% or More of Each Segment's Sales	3
Concentration Risk, Percentage	65.00%
Operating Segments [Member] | Sales Revenue, Net [Member] | Customer Concentration Risk [Member] | Optical Communications [Member]
Number of Customers Individually Accounting for 10% or More of Each Segment's Sales	1
Concentration Risk, Percentage	15.00%
Operating Segments [Member] | Sales Revenue, Net [Member] | Customer Concentration Risk [Member] | Environmental Technologies [Member]
Number of Customers Individually Accounting for 10% or More of Each Segment's Sales	3
Concentration Risk, Percentage	85.00%
Operating Segments [Member] | Sales Revenue, Net [Member] | Customer Concentration Risk [Member] | Specialty Materials [Member]
Number of Customers Individually Accounting for 10% or More of Each Segment's Sales	3
Concentration Risk, Percentage	56.00%
Operating Segments [Member] | Sales Revenue, Net [Member] | Customer Concentration Risk [Member] | Life Sciences [Member]
Number of Customers Individually Accounting for 10% or More of Each Segment's Sales	2
Concentration Risk, Percentage	46.00%
Minimum [Member]
Number of Material Formulations	150