Quarterly report pursuant to Section 13 or 15(d)

Note 10 - Leases (Details Textual)

v3.20.1
Note 10 - Leases (Details Textual)
3 Months Ended 6 Months Ended
Jun. 30, 2019
ft²
Mar. 31, 2020
USD ($)
ft²
Mar. 31, 2020
USD ($)
ft²
Feb. 12, 2020
ft²
Operating Lease, Weighted Average Discount Rate, Percent   3.48% 3.48%  
Operating Lease, Payments | $   $ 168,815 $ 336,655  
Weighted Average [Member]        
Lessee, Operating Lease, Term of Contract (Year)   4 years 284 days 4 years 284 days  
7050 Winnetka Avenue North, Brooklyn Park, Minnesota [Member]        
Area of Real Estate Property (Square Foot)   71,000 71,000  
Lessee, Operating Lease, Term of Contract (Year)   10 years 62 days 10 years 62 days  
Additional area of rental space (Square Foot) 14,000      
Operating Lease Termination Fee | $     $ 249,000  
Tijuana, Mexico [Member]        
Area of Real Estate Property (Square Foot)   46,000 46,000  
Lessee, Operating Lease, Term of Contract (Year)   3 years 3 years  
Tijuana, Mexico 2 [Member]        
Area of Real Estate Property (Square Foot)       52,000
Lessee, Operating Lease, Term of Contract (Year)       3 years 180 days
Lessee, Operating Lease, Number of Options to Renew       2
Lessee, Operating Lease, Renewal Term (Year)       3 years