v3.26.3
Stockholders’ Equity - Narrative (Details)
$ / shares in Units, $ in Millions
 3 Months Ended 9 Months Ended
Nov. 03, 2026
$ / shares
Jan. 02, 2026
vote
$ / shares
shares
Sep. 30, 2026
USD ($)
$ / shares
shares
Jun. 30, 2026
USD ($)
Sep. 30, 2026
USD ($)
$ / shares
shares
Sep. 30, 2025
USD ($)
Class of Stock [Line Items]            
Preferred stock, authorized (in shares) | shares   20,000,000 20,000,000   20,000,000  
Dividends paid | $         $ 106 $ 0
Dividends declared (in dollars per share) | $ / shares     $ 0.375   $ 1.125  
Repurchases of common stock, accelerated share repurchase | $     $ 100 $ 100    
Subsequent Event            
Class of Stock [Line Items]            
Dividends declared (in dollars per share) | $ / shares $ 0.375          
Class A Common Stock            
Class of Stock [Line Items]            
Common stock, authorized (in shares) | shares   7,500,000,000 7,500,000,000   7,500,000,000  
Common stock, par value (in dollars per share) | $ / shares   $ 0.01 $ 0.01   $ 0.01  
Number of Class A common share issued upon conversion of each Class B common share (in shares) | shares   1        
Class B Common Stock            
Class of Stock [Line Items]            
Common stock, authorized (in shares) | shares   75,000,000 75,000,000   75,000,000  
Common stock, par value (in dollars per share) | $ / shares   $ 0.01 $ 0.01   $ 0.01  
Number of votes per share | vote   15        
Percentage of total votes cast   33.33%        
Holders Of Comcast Class A Common Stock And Comcast Class B Common Stock | Versant Class A Common Stock And Versant Class B Common Stock | Separation And Distribution            
Class of Stock [Line Items]            
Percentage of ownership after distribution   100.00%        
Distribution ratio   0.04