Note 13 - Asset Dispositions, Assets Held for Sale and Asset Impairments (Details Textual) $ in Millions	6 Months Ended
Jun. 30, 2024 USD ($)	Jun. 30, 2023 USD ($)	Dec. 31, 2023
Number Of Vessels Sold Or Scrapped	4	6
Proceeds from Sale of Vessels	$ 14.8	$ 8.7
Gain (Loss) on Sale of Assets and Asset Impairment Charges	$ 13.0	$ 3.6
Number of Vessels, Held for Sale	0	2	0
Asset Held For Sale, Net Book Value		$ 0.6

Amount of gain (loss) from the difference between the sale price or salvage price and the book value of an asset that was sold or retired, and gain (loss) from the write down of assets from their carrying value to fair value.

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

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