Note 8 - Loan Payable - Schedule of Standby Fees Based on Total Funded Debt to EBITDA Ratio (Details)	12 Months Ended
	Dec. 31, 2019
Debt to EBITDA is Less Than 1 [Member]
Standby fees	0.30%
Debt to EBITDA is Greater Than or Equal to 1 and Less Than 2 [Member]
Standby fees	0.37%
Debt to EBITDA is Greater Than or Equal to 2 and Less Than 2.50 [Member]
Standby fees	0.47%
Debt to EBITDA is Greater Than or Equal to 2.50 [Member]
Standby fees	0.57%
Bank of Montreal and Royal Bank of Canada [Member] | London Interbank Offered Rate (LIBOR) [Member] | Debt to EBITDA is Less Than 1 [Member]
Basis Spread on Variable Rate	1.50%
Bank of Montreal and Royal Bank of Canada [Member] | London Interbank Offered Rate (LIBOR) [Member] | Debt to EBITDA is Greater Than or Equal to 1 and Less Than 2 [Member]
Basis Spread on Variable Rate	1.85%
Bank of Montreal and Royal Bank of Canada [Member] | London Interbank Offered Rate (LIBOR) [Member] | Debt to EBITDA is Greater Than or Equal to 2 and Less Than 2.50 [Member]
Basis Spread on Variable Rate	2.35%
Bank of Montreal and Royal Bank of Canada [Member] | London Interbank Offered Rate (LIBOR) [Member] | Debt to EBITDA is Greater Than or Equal to 2.50 [Member]
Basis Spread on Variable Rate	2.85%
Bank of Montreal and Royal Bank of Canada [Member] | Base Rate [Member] | Debt to EBITDA is Less Than 1 [Member]
Basis Spread on Variable Rate	0.25%
Bank of Montreal and Royal Bank of Canada [Member] | Base Rate [Member] | Debt to EBITDA is Greater Than or Equal to 1 and Less Than 2 [Member]
Basis Spread on Variable Rate	0.60%
Bank of Montreal and Royal Bank of Canada [Member] | Base Rate [Member] | Debt to EBITDA is Greater Than or Equal to 2 and Less Than 2.50 [Member]
Basis Spread on Variable Rate	1.10%
Bank of Montreal and Royal Bank of Canada [Member] | Base Rate [Member] | Debt to EBITDA is Greater Than or Equal to 2.50 [Member]
Basis Spread on Variable Rate	1.60%