Fair Value of Financial Instruments - Fair value on a non-recurring basis (Details) - Fair Value, Nonrecurring [Member] - USD ($) $ in Thousands |
Jun. 30, 2021 |
Dec. 31, 2020 |
|---|---|---|
| Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items] | ||
| Assets held for sale | $ 30,000 | |
| Total | 30,000 | $ 48,072 |
| Vessels, port terminals and other fixed assets, net | 38,054 | |
| Operating lease assets | 10,018 | |
| Fair Value, Inputs, Level 1 [Member] | ||
| Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items] | ||
| Assets held for sale | 30,000 | |
| Total | $ 30,000 | 6,644 |
| Vessels, port terminals and other fixed assets, net | 6,644 | |
| Operating lease assets | 0 | |
| Fair Value, Inputs, Level 2 [Member] | ||
| Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items] | ||
| Total | 41,428 | |
| Vessels, port terminals and other fixed assets, net | 31,410 | |
| Operating lease assets | $ 10,018 |