v3.26.1
Related-Party Transactions - Narrative (Details) - USD ($)
$ in Thousands
3 Months Ended 6 Months Ended
Mar. 31, 2026
Mar. 31, 2025
Mar. 31, 2026
Mar. 31, 2025
Related-Party Transactions        
Total revenue $ 464,891 $ 431,618 $ 940,125 $ 618,406
Provision for receivables from related parties 0   0  
Related Party        
Related-Party Transactions        
Total revenue 40,165 167,211 222,397 237,800
Consulting Services Revenue | Related Party        
Related-Party Transactions        
Total revenue $ 100 $ 3,800 $ 200 $ 5,400
AES Grid Stability | Class B-1 common stock | Fluence Energy, Inc        
Related-Party Transactions        
Investment owned (in shares) 51,499,195   51,499,195  
Siemens Industry | Class A common stock | Fluence Energy, Inc        
Related-Party Transactions        
Investment owned (in shares) 51,499,195   51,499,195