Note 7 - Inventory (Details Textual) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Inventory, Net, Total	$ 35	$ 43

Amount after valuation and LIFO reserves of inventory expected to be sold, or consumed within one year or operating cycle, if longer.

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant