Investment in affiliate companies and available-for-sale securities - Summarized financial information of the affiliate companies (Details) - USD ($)
$ in Thousands
3 Months Ended 6 Months Ended
Jun. 30, 2021
Mar. 31, 2021
Jun. 30, 2020
Mar. 31, 2020
Jun. 30, 2021
Jun. 30, 2020
Schedule of Equity Method Investments [Line Items]            
Revenue $ 143,624   $ 97,127   $ 260,575 $ 188,210
Net income/ (loss) 24,545 $ 1,314 (30,937) $ (50,726) 25,859 (81,663)
Navios Partners [Member]            
Schedule of Equity Method Investments [Line Items]            
Revenue 152,009   46,549   217,072 93,039
Time charter and voyage expenses (5,869)   (1,940)   (8,364) (5,038)
Direct vessel expenses (3,989)   (2,385)   (7,143) (4,934)
Vessel operating expenses (41,771)   (21,930)   (64,733) (44,135)
Net income/ (loss) $ 99,913   $ (14,641)   $ 236,592 $ (25,365)