Note 6 - Leases - Balance Sheet Information (Details) - USD ($) $ in Thousands	Jun. 30, 2019	Dec. 31, 2018
Short-term lease liability	$ 43
Long-term lease liability	15,045	$ 14,411
Other Assets [Member]
ROU assets	80
Other Liabilities [Member]
Short-term lease liability	43
Other Noncurrent Liabilities [Member]
Long-term lease liability	$ 37