v3.25.1
FAIR VALUE MEASUREMENTS - Fair Value of Assets Measured on a Recurring Basis (Detail) - USD ($)
$ in Thousands
Mar. 31, 2025
Dec. 31, 2024
Financial assets    
Cash equivalents $ 40,904 $ 69,089
Marketable debt securities 1,646,272 1,789,009
Marketable equity securities 7,200 8,156
Recurring    
Financial assets    
Marketable equity securities 7,200 8,156
Total financial assets 1,851,658 1,988,854
Financial liabilities    
Development derivative liability 540,529 486,919
Recurring | Quoted Prices in Active Markets (Level 1)    
Financial assets    
Marketable equity securities 7,200 8,156
Total financial assets 205,386 199,845
Financial liabilities    
Development derivative liability 0 0
Recurring | Significant Observable Inputs (Level 2)    
Financial assets    
Marketable equity securities 0 0
Total financial assets 1,646,272 1,789,009
Financial liabilities    
Development derivative liability 0 0
Recurring | Significant Unobservable Inputs (Level 3)    
Financial assets    
Marketable equity securities 0 0
Total financial assets 0 0
Financial liabilities    
Development derivative liability 540,529 486,919
Recurring | Money market funds    
Financial assets    
Cash equivalents 197,274 190,779
Restricted cash (money market funds) 912 910
Recurring | Money market funds | Quoted Prices in Active Markets (Level 1)    
Financial assets    
Cash equivalents 197,274 190,779
Restricted cash (money market funds) 912 910
Recurring | Money market funds | Significant Observable Inputs (Level 2)    
Financial assets    
Cash equivalents 0 0
Restricted cash (money market funds) 0 0
Recurring | Money market funds | Significant Unobservable Inputs (Level 3)    
Financial assets    
Cash equivalents 0 0
Restricted cash (money market funds) 0 0
Recurring | U.S. treasury securities    
Financial assets    
Cash equivalents 20,978 36,428
Marketable debt securities 782,548 921,627
Recurring | U.S. treasury securities | Quoted Prices in Active Markets (Level 1)    
Financial assets    
Cash equivalents 0 0
Marketable debt securities 0 0
Recurring | U.S. treasury securities | Significant Observable Inputs (Level 2)    
Financial assets    
Cash equivalents 20,978 36,428
Marketable debt securities 782,548 921,627
Recurring | U.S. treasury securities | Significant Unobservable Inputs (Level 3)    
Financial assets    
Cash equivalents 0 0
Marketable debt securities 0 0
Recurring | Commercial paper    
Financial assets    
Cash equivalents 19,926 22,709
Marketable debt securities 28,000 35,408
Recurring | Commercial paper | Quoted Prices in Active Markets (Level 1)    
Financial assets    
Cash equivalents 0 0
Marketable debt securities 0 0
Recurring | Commercial paper | Significant Observable Inputs (Level 2)    
Financial assets    
Cash equivalents 19,926 22,709
Marketable debt securities 28,000 35,408
Recurring | Commercial paper | Significant Unobservable Inputs (Level 3)    
Financial assets    
Cash equivalents 0 0
Marketable debt securities 0 0
Recurring | U.S. government-sponsored enterprise securities    
Financial assets    
Cash equivalents   9,952
Marketable debt securities 417,074 396,143
Recurring | U.S. government-sponsored enterprise securities | Quoted Prices in Active Markets (Level 1)    
Financial assets    
Cash equivalents   0
Marketable debt securities 0 0
Recurring | U.S. government-sponsored enterprise securities | Significant Observable Inputs (Level 2)    
Financial assets    
Cash equivalents   9,952
Marketable debt securities 417,074 396,143
Recurring | U.S. government-sponsored enterprise securities | Significant Unobservable Inputs (Level 3)    
Financial assets    
Cash equivalents   0
Marketable debt securities 0 0
Recurring | Corporate notes    
Financial assets    
Marketable debt securities 372,736 361,739
Recurring | Corporate notes | Quoted Prices in Active Markets (Level 1)    
Financial assets    
Marketable debt securities 0 0
Recurring | Corporate notes | Significant Observable Inputs (Level 2)    
Financial assets    
Marketable debt securities 372,736 361,739
Recurring | Corporate notes | Significant Unobservable Inputs (Level 3)    
Financial assets    
Marketable debt securities 0 0
Recurring | Municipal securities    
Financial assets    
Marketable debt securities 5,010 5,003
Recurring | Municipal securities | Quoted Prices in Active Markets (Level 1)    
Financial assets    
Marketable debt securities 0 0
Recurring | Municipal securities | Significant Observable Inputs (Level 2)    
Financial assets    
Marketable debt securities 5,010 5,003
Recurring | Municipal securities | Significant Unobservable Inputs (Level 3)    
Financial assets    
Marketable debt securities $ 0 $ 0