Details Of Certain Accounts - Other Assets, Net (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Deferred recertification and dry dock costs, net	$ 19,073	$ 21,464
Deferred costs	916	861
Charter deposit	12,544	12,544
Intangible assets with finite lives, net	3,756	3,809
Other	1,221	1,335
Total other assets, net	$ 37,510	$ 40,013