Note 8 - Leases - Maturities of Lease Liabilities (Details) - USD ($)	Mar. 31, 2020	Dec. 31, 2019
Remainder of: 2020, financing	$ 99,000
Remainder of: 2020, operating	783,000
Remainder of: 2020, total	882,000
2021, financing	132,000
2021, operating	1,020,000
2021, total	1,152,000
2022, financing	127,000
2022, operating	1,011,000
2022, total	1,138,000
2023, financing	53,000
2023, operating	1,002,000
2023, total	1,055,000
2024, financing	10,000
2024, operating	856,000
2024, total	866,000
Thereafter, financing
Thereafter, operating	8,979,000
Thereafter, total	8,979,000
Total undiscounted future minimum lease cash payments, financing	421,000
Total undiscounted future minimum lease cash payments, operating	13,651,000
Total undiscounted future minimum lease cash payments, operating	14,072,000
Present value discount, financing	(13,000)
Present value discount, operating	(4,679,000)
Present value discount, total	(4,692,000)
Lease liability, financing	407,603	$ 438,580
Lease liability, operating	8,971,587	$ 9,105,503
Lease liability, total	$ 9,380,000