Note 14 - Asset Dispositions, Assets Held for Sale and Asset Impairments (Details Textual)	3 Months Ended
	Mar. 31, 2023 USD ($)	Dec. 31, 2022
Number of Vessels, Held for Sale, Addition	5
Number of Vessels, Held for Sale	3	8
Asset Held For Sale, Net Book Value	$ 0.7
Proceeds from Sale of Vessels	5.7
Gain (Loss) on Sale of Assets and Asset Impairment Charges	$ 2.2
Number of Vessels, Held for Sale, Sold	5
Number of Vessels, Transfer from Held for Sale to Active Fleet	1
Impairment Charge Recaptured	$ 0.5