Note 10 - Debt Financing (Details Textual) - Paycheck Protection Program CARES Act [Member] - USD ($) $ in Thousands			9 Months Ended
Jan. 08, 2021	Apr. 17, 2020	Sep. 30, 2021	Sep. 30, 2020
Proceeds from Issuance of Long-term Debt, Total		$ 1,556	$ 0	$ 1,556
Debt Instrument, Decrease, Forgiveness	$ 1,556

The cash inflow from a debt initially having maturity due after one year or beyond the operating cycle, if longer.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 14
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=123570139&loc=d3e3255-108585

Name:	us-gaap_ProceedsFromIssuanceOfLongTermDebt
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration