Note 3 - Loan to Affiliate (Details Textual) - Senior Secured Term Loan [Member] - USD ($)	3 Months Ended	6 Months Ended
Jun. 30, 2021	Jun. 30, 2020	Mar. 19, 2019
Notes Receivable, Related Parties			$ 2,000,000
Interest Income, Related Party	$ 71,000	$ 142,000
The Lenders [Member]
Notes Receivable, Related Parties			$ 10,500,000

For an unclassified balance sheet, amounts due from parties associated with the reporting entity as evidenced by a written promise to pay.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03.3)
-URI http://asc.fasb.org/extlink&oid=120400017&loc=d3e572229-122910

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08(k)(1))
-URI http://asc.fasb.org/extlink&oid=120395691&loc=d3e23780-122690

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 850
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=6457730&loc=d3e39549-107864

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant