Note 10 - Related Party Transaction (Details Textual) - USD ($)	12 Months Ended
Dec. 31, 2023	Dec. 31, 2022
Operating Lease, Expense	$ 1,339,000	$ 1,323,000
ISC Properties LLC [Member]
Related Party Ownership Percentage	100.00%
Operating Lease, Expense	$ 357,000	$ 333,000

Amount of operating lease expense. Excludes sublease income.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 842
-SubTopic 20
-Name Accounting Standards Codification
-Section 45
-Paragraph 4
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479041/842-20-45-4

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