Note 4 - Leases, Right-to-use Assets and Related Liabilities - Future Minimum Payments Under Non-cancelable Operating Leases (Details) $ in Thousands	Jun. 30, 2020 USD ($)
2020 (remaining), financing leases	$ 2
2020 (remaining), operating leases	193
2021, financing leases	4
2021, operating leases	178
2022, financing leases	4
2022, operating leases
2023, financing leases	4
2023, operating leases
2024 and thereafter, financing leases	5
2024 and thereafter, operating leases
Total, financing leases	19
Total, operating leases	371
Less: Amounts representing present value discounts, financing leases	(7)
Less: Amounts representing present value discounts, operating leases	(18)
Accounts Payable, Accrued Liabilities and Other Noncurrent Liabilities [Member]
Total lease liabilities, financing leases	12
Total lease liabilities, operating leases	$ 353