Note 11 - Leases - Operating Leases Balance Sheet Information (Details) - USD ($) $ in Thousands		Dec. 31, 2021	Dec. 31, 2020
Noncurrent operating lease liabilities		$ 291	$ 411
Other Noncurrent Assets [Member]
Other noncurrent assets (a)	[1]	540	918
Accrued and Other Current Liabilities [Member]
Accrued and other current liabilities		249	507
Other Noncurrent Liabilities [Member]
Noncurrent operating lease liabilities		291	411
Other Liabilities [Member]
Total liabilities		$ 540	$ 918

[1] Operating lease asset balances at December 31, 2021 and 2020.