Investments in affiliates and investments in available-for-sale securities - Navios Containers (Details) - USD ($)
$ / shares in Units, $ in Thousands
2 Months Ended 3 Months Ended 5 Months Ended 11 Months Ended 12 Months Ended
Feb. 28, 2019
Mar. 13, 2018
Dec. 31, 2019
Mar. 31, 2018
Jun. 08, 2017
Dec. 03, 2018
Nov. 30, 2018
Dec. 31, 2020
Dec. 31, 2019
Dec. 31, 2018
Investments In And Advances To Affiliates [Line Items]                    
Equity in net (losses)/earnings of affiliated companies               $ (1,293) $ (9,185) $ (80,205)
Investments in affiliate companies     $ 64,352         $ 56,988 $ 64,352  
Navios Containers                    
Investments In And Advances To Affiliates [Line Items]                    
Investments on the equity   $ 500     $ 5,000          
Ownership percentage of Navios Holdings               3.90% 3.70%  
Equity in net (losses)/earnings of affiliated companies     155       $ 417 $ 130    
Investments in affiliate companies     $ 2,682         2,812 $ 2,682  
Market value of the investment               $ 5,179    
Navios Containers                    
Investments In And Advances To Affiliates [Line Items]                    
Ownership interest             96.30%      
Date of conversion into a limited partnership               Nov. 30, 2018    
Warrants | Navios Containers                    
Investments In And Advances To Affiliates [Line Items]                    
Ownership interest         1.70%          
Navios Containers                    
Investments In And Advances To Affiliates [Line Items]                    
Ownership percentage of Navios Holdings               3.70%    
Navios Partners                    
Investments In And Advances To Affiliates [Line Items]                    
Partners' Capital Account, Units, Sold in Private Placement 380,952     1,370,044         1,464,494  
Navios Partners | Navios Containers                    
Investments In And Advances To Affiliates [Line Items]                    
Consolidation Less Than Wholly Owned Subsidiary Parent Ownership Interest Changes Purchase Of Interest By Parent         $ 30,000          
Navios Partners | Warrants | Navios Containers                    
Investments In And Advances To Affiliates [Line Items]                    
Ownership percentage         6.80%          
Navios Partners | Navios Containers                    
Investments In And Advances To Affiliates [Line Items]                    
Percentage of partners' capital           2.50%        
Navios Containers | Common units                    
Investments In And Advances To Affiliates [Line Items]                    
Partners' Capital Account, Units, Sold in Private Placement         10,057,645          
Price per share offered         $ 5          
Proceeds from Issuance of Private Placement         $ 50,288