v3.26.1
Redeemable Convertible Preferred Stock and Shareholders’ Equity - Narrative (Details)
$ / shares in Units, shares in Millions, $ in Millions
 1 Months Ended 3 Months Ended 6 Months Ended
May 31, 2026
Jun. 30, 2026
USD ($)
class
vote
$ / shares
shares
Jun. 30, 2025
USD ($)
shares
Jun. 30, 2026
USD ($)
class
vote
$ / shares
shares
Jun. 30, 2025
USD ($)
shares
Dec. 31, 2025
$ / shares
Class of Stock [Line Items]            
Number of classes of common stock | class   3   3    
Number of classes of preferred stock | class   1   1    
Common stock authorized (in shares)   52,257.0   52,257.0    
Preferred stock authorized (in shares)   2,400.0   2,400.0    
Stock split conversion ratio 5          
Preferred stock, par value (in USD per share) | $ / shares   $ 0.001   $ 0.001   $ 0.001
Common stock and redeemable convertible preferred stock repurchased | $   $ 80   $ 2,013    
Common stock repurchased (in shares)   10.5 0.3   28.2  
Redeemable convertible preferred stock repurchased (in shares)   0.0   2.1    
Common stock repurchased | $   $ 80 $ 12   $ 520  
Share Repurchases from Existing Shareholders            
Class of Stock [Line Items]            
Common stock repurchased (in shares)       41.0    
Common stock repurchased | $       $ 1,944    
Share Repurchases from Current and Former xAI Employees            
Class of Stock [Line Items]            
Common stock repurchased (in shares)       25.0    
Common stock repurchased | $       $ 2,413    
Class A Common Stock            
Class of Stock [Line Items]            
Common stock authorized (in shares)   36,132.0   36,132.0    
Common stock, par value (in USD per share) | $ / shares   $ 0.001   $ 0.001   0.001
Number of votes per share of common stock held | vote   1   1    
Class B Common Stock            
Class of Stock [Line Items]            
Common stock authorized (in shares)   6,125.0   6,125.0    
Common stock, par value (in USD per share) | $ / shares   $ 0.001   $ 0.001   0.001
Common stock conversion ratio   1   1    
Number of votes per share of common stock held | vote   10   10    
Class C Common Stock            
Class of Stock [Line Items]            
Common stock authorized (in shares)   10,000.0   10,000.0    
Common stock, par value (in USD per share) | $ / shares   $ 0.001   $ 0.001   $ 0.001