v3.25.2
Basis of presentation (Details)
 6 Months Ended 12 Months Ended
Jun. 30, 2025
Jun. 30, 2024
Dec. 31, 2024
Dec. 31, 2023
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Line Items]        
Ownership Interest     100.00%  
Advent Technologies Inc. [Member]        
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Line Items]        
Company Name Advent Technologies, Inc.   Advent Technologies, Inc.  
Country of Incorporation USA   USA  
Statements of Operations date 01/01 – 6/30 01/01 – 6/30 01/01 – 12/31 01/01 – 12/31
Advent Technologies Inc. [Member] | Direct Ownership [Member]        
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Line Items]        
Ownership Interest 100.00%   100.00%  
Advent Technologies Inc. [Member] | Indirect Ownership [Member]        
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Line Items]        
Ownership Interest    
Advent Technologies S.A. [Member]        
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Line Items]        
Company Name Advent Technologies S.A.   Advent Technologies S.A.  
Country of Incorporation Greece   Greece  
Statements of Operations date 01/01 – 6/30 01/01 – 6/30 01/01 – 12/31 01/01 – 12/31
Advent Technologies S.A. [Member] | Direct Ownership [Member]        
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Line Items]        
Ownership Interest    
Advent Technologies S.A. [Member] | Indirect Ownership [Member]        
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Line Items]        
Ownership Interest 100.00%   100.00%  
Advent Technologies LLC [Member]        
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Line Items]        
Company Name Advent Technologies LLC   Advent Technologies LLC  
Country of Incorporation USA   USA  
Statements of Operations date 01/01 – 6/30 01/01 – 6/30 01/01 – 12/31 01/01 – 12/31
Advent Technologies LLC [Member] | Direct Ownership [Member]        
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Line Items]        
Ownership Interest    
Advent Technologies LLC [Member] | Indirect Ownership [Member]        
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Line Items]        
Ownership Interest 100.00%   100.00%  
Advent Technologies GmbH [Member]        
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Line Items]        
Company Name Advent Technologies GmbH   Advent Technologies GmbH  
Country of Incorporation Germany   Germany  
Statements of Operations date 01/01 – 6/30 01/01 – 6/30 01/01 – 12/31 01/01 – 12/31
Advent Technologies GmbH [Member] | Direct Ownership [Member]        
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Line Items]        
Ownership Interest 100.00%   100.00%  
Advent Technologies GmbH [Member] | Indirect Ownership [Member]        
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Line Items]        
Ownership Interest