v3.26.1
Revenue Recognition - Schedule of Disaggregation of Revenue (Details) - USD ($)
$ in Millions
 3 Months Ended 6 Months Ended
Jun. 30, 2026
Jun. 30, 2025
Jun. 30, 2026
Jun. 30, 2025
Disaggregation of Revenue [Line Items]        
Revenue $ 4,306 $ 2,060 $ 7,010 $ 3,416
Gross commission income        
Disaggregation of Revenue [Line Items]        
Revenue 3,947 2,008 6,400 3,331
Service revenue        
Disaggregation of Revenue [Line Items]        
Revenue 205 39 348 61
Franchise fees        
Disaggregation of Revenue [Line Items]        
Revenue 119 8 193 13
Other        
Disaggregation of Revenue [Line Items]        
Revenue 35 5 69 11
Operating Segments        
Disaggregation of Revenue [Line Items]        
Revenue 4,306 2,060 7,010 3,416
Operating Segments | Brokerage        
Disaggregation of Revenue [Line Items]        
Revenue 3,960 2,013 6,427 3,341
Operating Segments | Franchise        
Disaggregation of Revenue [Line Items]        
Revenue 135 8 225 14
Operating Segments | Integrated Services        
Disaggregation of Revenue [Line Items]        
Revenue 211 39 358 61
Operating Segments | Gross commission income | Brokerage        
Disaggregation of Revenue [Line Items]        
Revenue 3,947 2,008 6,400 3,331
Operating Segments | Gross commission income | Franchise        
Disaggregation of Revenue [Line Items]        
Revenue 0 0 0 0
Operating Segments | Gross commission income | Integrated Services        
Disaggregation of Revenue [Line Items]        
Revenue 0 0 0 0
Operating Segments | Service revenue | Brokerage        
Disaggregation of Revenue [Line Items]        
Revenue 0 0 0 0
Operating Segments | Service revenue | Franchise        
Disaggregation of Revenue [Line Items]        
Revenue 0 0 0 0
Operating Segments | Service revenue | Integrated Services        
Disaggregation of Revenue [Line Items]        
Revenue 205 39 348 61
Operating Segments | Franchise fees | Brokerage        
Disaggregation of Revenue [Line Items]        
Revenue 0 0 0 0
Operating Segments | Franchise fees | Franchise        
Disaggregation of Revenue [Line Items]        
Revenue 119 8 193 13
Operating Segments | Franchise fees | Integrated Services        
Disaggregation of Revenue [Line Items]        
Revenue 0 0 0 0
Operating Segments | Other | Brokerage        
Disaggregation of Revenue [Line Items]        
Revenue 13 5 27 10
Operating Segments | Other | Franchise        
Disaggregation of Revenue [Line Items]        
Revenue 16 0 32 1
Operating Segments | Other | Integrated Services        
Disaggregation of Revenue [Line Items]        
Revenue $ 6 $ 0 $ 10 $ 0