v3.26.1
Segment Information - Financial Information (Details) - USD ($)
$ in Millions
 3 Months Ended
Mar. 31, 2026
Mar. 31, 2025
Segment Reporting Information [Line Items]    
Revenue $ 15.6 $ 188.8
Less:    
Total research and development expense 60.3 90.8
General and administrative expense 19.1 26.6
Income tax expense 0.1 0.2
Interest income, net 6.4 11.7
Segment net (loss) income (57.6) 82.9
Reportable Segment    
Segment Reporting Information [Line Items]    
Revenue 15.6 188.8
Less:    
Non program-specific external expense 9.2 13.9
Compensation and related personnel expense (including stock-based compensation) 21.3 36.9
Other research and development expense 2.4 3.1
Total research and development expense 60.3 90.8
General and administrative expense 19.1 26.6
Other segment expense, net (**) 0.1 0.0
Income tax expense 0.1 0.2
Interest income, net 6.4 11.7
Segment net (loss) income (57.6) 82.9
Reportable Segment | Vepdegestrant ARV-471    
Less:    
Program-specific external expense 8.9 24.1
Reportable Segment | ARV-806    
Less:    
Program-specific external expense 6.5 0.9
Reportable Segment | ARV-102    
Less:    
Program-specific external expense 5.5 6.5
Reportable Segment | ARV-393    
Less:    
Program-specific external expense 3.7 2.6
Reportable Segment | Bavdegalutamide (ARV-110)    
Less:    
Program-specific external expense 0.2 1.1
Reportable Segment | Other programs    
Less:    
Program-specific external expense $ 2.6 $ 1.7