Note 5 - Leases - Maturity of Lease Liabilities (Details) - USD ($)	Jun. 30, 2019	Jan. 01, 2019
Operating leases, remaining 2019	$ 447,000
Finance leases, remaining 2019	213,000
Total, remaining 2019	660,000
Operating leases, 2020	858,000
Finance leases, 2020	398,000
Total, 2020	1,256,000
Operating leases, 2021	722,000
Finance leases, 2021	398,000
Total, 2021	1,120,000
Operating leases, 2022	726,000
Finance leases, 2022	223,000
Total, 2022	949,000
Operating leases, 2023	738,000
Finance leases, 2023	2,000
Total, 2023	740,000
Operating leases, thereafter	3,380,000
Finance leases, thereafter
Total, thereafter	3,380,000
Operating leases, total lease payments	6,871,000
Finance leases, total lease payments	1,234,000
Total, total lease payments	8,105,000
Operating leases, less: Interest	(1,379,000)
Finance leases, less: Interest	(94,000)
Total, less: Interest	(1,473,000)
Operating leases, present value of lease liabilities	5,492,000	$ 5,731,000
Finance leases, present value of lease liabilities	1,140,000
Total, present value of lease liabilities	$ 6,632,000