v3.25.2
Fair Value Measures - Balance Sheet Grouping (Q2) (Details) - USD ($)
$ in Thousands
Jun. 30, 2025
Dec. 31, 2024
Dec. 31, 2023
Financial assets:      
Financial assets   $ 0 $ 2,368
Total financial assets $ 579,430 114,716 512,605
Financial liabilities:      
Total financial liabilities 698 200,089 527,047
Level 1 | Money market funds | Cash and cash equivalents      
Financial assets:      
Financial assets 55,508 2,411 87,258
Level 1 | Money market funds | Restricted cash and cash equivalents, current      
Financial assets:      
Financial assets 518,199 24,185 42,940
Level 1 | Money market funds | Restricted cash and cash equivalents, non-current      
Financial assets:      
Financial assets 0 56,250 206,846
Level 2      
Financial liabilities:      
Power purchase agreements 271 0  
Level 2 | Certificates of deposit      
Financial assets:      
Financial assets 0 29,308 171,734
Level 2 | Foreign exchange forward contracts      
Financial assets:      
Derivative assets 2,279 0  
Level 3      
Financial assets:      
Derivative assets 3,444 2,562 1,459
Financial liabilities:      
Power purchase agreements 427 444 0
Warrant liabilities $ 0 $ 199,645 $ 70,930