Quarterly report pursuant to Section 13 or 15(d)

Note 10 - Leases (Details Textual)

v3.19.3.a.u2
Note 10 - Leases (Details Textual)
 3 Months Ended
Jun. 30, 2019
a
Dec. 31, 2019
USD ($)
a
Dec. 31, 2018
USD ($)
Operating Lease, Weighted Average Discount Rate, Percent   3.51%  
Operating Lease, Payments   $ 167,840  
Weighted Average [Member]      
Lessee, Operating Lease, Term of Contract   4 years 343 days  
Cost of Sales [Member]      
Operating Lease, Expense   $ 185,628  
Operating Leases, Rent Expense, Total     $ 168,828
General and Administrative Expense [Member]      
Operating Lease, Expense   $ 56,366  
Operating Leases, Rent Expense, Total     $ 53,538
7050 Winnetka Avenue North, Brooklyn Park, Minnesota [Member]      
Area of Real Estate Property | a   71,000  
Lessee, Operating Lease, Term of Contract   10 years 62 days  
Additional area of rental space | a 14,000    
Operating Lease Termination Fee   $ 249,000  
Tijuana, Mexico [Member]      
Area of Real Estate Property | a   46,000  
Lessee, Operating Lease, Term of Contract   3 years