Note 2 - Sale of Subsidiaries and Subsequent Events (Details Textual) - Klein Marine Services, Inc. [Member] - Subsequent Event [Member] $ in Millions	Aug. 21, 2023 USD ($)
Disposal Group, Including Discontinued Operation, Consideration	$ 11.5
Gain (Loss) on Disposition of Business	$ 2.0

Amount of gain (loss) from sale and disposal of integrated set of activities and assets capable of being conducted and managed for purpose of providing return in form of dividend, lower cost, or other economic benefit to investor, owner, member and participant.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 230
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 28
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482740/230-10-45-28

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 810
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 1B
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481203/810-10-50-1B

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration