Note 8 - Assets Held for Sale, Asset Sales and Asset Impairments - Activity in Assets Held for Sale (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2022 USD ($)	Dec. 31, 2021 USD ($)	Dec. 31, 2020 USD ($)	Dec. 31, 2019 USD ($)
Beginning balance	18	23
Additions	3	7	32	46
Sales			(53)
Reactivation	(1)	(1)	0
Impairment		$ 13,700	$ 75,200
Ending balance	8	18	23
Vessels Held for Sale [Member]
Beginning balance	18	23	46
Beginning balance	$ 14,421	$ 34,396	$ 39,287
Additions	3	7	32
Additions	$ 2,561	$ 18,096	$ 97,663
Sales	(12)	(9)	(53)
Sales	$ (11,287)	$ (15,433)	$ (26,877)
Reactivation	(1)	(3)	(2)
Reactivation	$ (1,500)	$ (7,250)	$ (500)
Impairment	$ 0	$ (15,388)	$ (75,177)
Ending balance	8	18	23	46
Ending balance	$ 4,195	$ 14,421	$ 34,396	$ 39,287