Note 8 - Leases (Details Textual) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Jun. 30, 2023	Mar. 31, 2023	Sep. 30, 2022	Mar. 31, 2022
Operating Lease, Right-of-Use Asset, Amortization Expense	$ 1,567	$ 1,241
Operating Lease, Right-of-Use Asset	4,987	5,770
Operating Lease, Liability	5,422
Environmental Technologies in Germany [Member]
Lessee, Operating Lease, Term of Contract (Month)				25 months
Operating Lease, Right-of-Use Asset	90			$ 90
Operating Lease, Liability	$ 90			$ 90
Process Technologies in Europe [Member] | Automobile Lease, One [Member]
Lessee, Operating Lease, Term of Contract (Month)				36 years
Process Technologies in Europe [Member] | Automobile Leases [Member]
Operating Lease, Right-of-Use Asset			$ 41	$ 30
Operating Lease, Liability			$ 41	$ 30
Process Technologies in Europe [Member] | Automobile Lease, Two [Member]
Lessee, Operating Lease, Term of Contract (Month)			48 years
Southeast Asia Operation [Member]
Lessee, Operating Lease, Term of Contract (Month)	36 months
Operating Lease, Right-of-Use Asset	$ 455
Operating Lease, Liability	$ 455
Process Technologies in the Netherlands [Member]
Lessee, Operating Lease, Term of Contract (Month)	36 years
Operating Lease, Right-of-Use Asset	$ 136
Operating Lease, Liability	$ 136
Lease Facility in Singapore [Member]
Operating Lease, Right-of-Use Asset		51				$ 51
Operating Lease, Liability		51				$ 51
Automobile Lease for Videology [Member]
Lessee, Operating Lease, Term of Contract (Month)					48 months
Operating Lease, Right-of-Use Asset		42			$ 42
Operating Lease, Liability		$ 42			$ 42
Facility for Acculogic Operation in Canada [Member]
Lessee, Operating Lease, Term of Contract (Month)		62 months
Operating Lease, Right-of-Use Asset		$ 942
Operating Lease, Liability		$ 942
Facility for Acculogic Operation in California [Member]
Lessee, Operating Lease, Term of Contract (Month)		37 months
Operating Lease, Right-of-Use Asset		$ 127
Operating Lease, Liability		$ 127