Fair Value of Financial Instruments - Fair value measurements (Details) - USD ($)
$ in Thousands |
Jun. 30, 2022 |
Dec. 31, 2021 |
| Defined Benefit Plan Disclosure [Line Items] |
|
|
| Cash and cash equivalents |
$ 46,220
|
$ 53,591
|
| Restricted cash |
8,726
|
84,260
|
| Investments in available-for-sale-securities |
220
|
219
|
| Senior and ship mortgage notes |
(572,943)
|
(1,142,545)
|
| Long-term debt, including current portion |
(382,536)
|
(173,213)
|
| Loans payable to affiliate companies, including current portion and Convertible Debenture |
(310,269)
|
(112,634)
|
| Fair Value, Inputs, Level 1 [Member] |
|
|
| Defined Benefit Plan Disclosure [Line Items] |
|
|
| Cash and cash equivalents |
46,220
|
53,591
|
| Restricted cash |
8,726
|
84,260
|
| Investments in available-for-sale-securities |
220
|
219
|
| Senior and ship mortgage notes |
(564,317)
|
(1,133,919)
|
| Fair Value, Inputs, Level 2 [Member] |
|
|
| Defined Benefit Plan Disclosure [Line Items] |
|
|
| Senior and ship mortgage notes |
(8,626)
|
(8,626)
|
| Long-term debt, including current portion |
(382,536)
|
(173,213)
|
| Loans payable to affiliate companies, including current portion and Convertible Debenture |
$ (310,269)
|
$ (112,634)
|