Note 14 - Asset Dispositions, Assets Held for Sale and Asset Impairments - Activity in Assets Held for Sale (Details) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2023 USD ($)	Jun. 30, 2022 USD ($)	Jun. 30, 2023 USD ($)	Jun. 30, 2022 USD ($)
Beginning balance			8
Additions				1
Ending balance	2	9	2	9
Vessels Held for Sale [Member]
Beginning balance	3	12	8	18
Beginning balance	$ 695	$ 8,591	$ 4,195	$ 14,421
Additions	0	1	0	1
Additions	$ 0	$ 2,500	$ 0	$ 2,500
Sales	(1)	(4)	(6)	(9)
Sales	$ (65)	$ (4,229)	$ (3,565)	$ (8,559)
Ending balance	2	9	2	9
Ending balance	$ 630	$ 6,862	$ 630	$ 6,862
Transfers			0	(1)
Transfers			$ 0	$ (1,500)