Note 15 - Subsequent Events (Details Textual) - Senior Unsecured Convertible Notes [Member] - Subsequent Event [Member] - USD ($) $ in Millions	May 20, 2022	May 02, 2022
Four Board Members [Member]
Proceeds from Issuance of Unsecured Debt		$ 5
Three Board Members and One Unrelated Party [Member]
Proceeds from Issuance of Unsecured Debt	$ 5

The cash inflow from the issuance of long-term debt that is not secured by collateral. Excludes proceeds from tax exempt unsecured debt.

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 https://asc.fasb.org/extlink&oid=126954810&loc=d3e3255-108585

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