v3.26.3
Investments and Fair Value Measurements - Summary Of Assets And Liabilities That Are Measured At Fair Value On A Recurring And Nonrecurring Basis (Detail) - USD ($)
$ in Thousands
Sep. 30, 2026
Dec. 31, 2025
Marketable securities:    
Debt securities $ 6,756,734 $ 5,729,892
Total 9,941,644 6,703,423
Level 1    
Marketable securities:    
Total 3,180,050 968,685
Level 2    
Marketable securities:    
Total 6,761,594 5,734,738
Level 3    
Marketable securities:    
Total 0 0
U.S. Treasury securities    
Marketable securities:    
Debt securities 6,756,734 5,729,892
Location, Statement of Financial Position, Balance [Axis]: us-gaap:CashAndCashEquivalentsAtCarryingValue | Money market funds    
Cash and cash equivalents:    
Cash and cash equivalents 2,994,667 945,330
Location, Statement of Financial Position, Balance [Axis]: us-gaap:CashAndCashEquivalentsAtCarryingValue | Money market funds | Level 1    
Cash and cash equivalents:    
Cash and cash equivalents 2,994,667 945,330
Location, Statement of Financial Position, Balance [Axis]: us-gaap:CashAndCashEquivalentsAtCarryingValue | Money market funds | Level 2    
Cash and cash equivalents:    
Cash and cash equivalents 0 0
Location, Statement of Financial Position, Balance [Axis]: us-gaap:CashAndCashEquivalentsAtCarryingValue | Money market funds | Level 3    
Cash and cash equivalents:    
Cash and cash equivalents 0 0
Location, Statement of Financial Position, Balance [Axis]: us-gaap:MarketableSecuritiesCurrent | U.S. Treasury securities    
Marketable securities:    
Debt securities 6,756,734 5,729,892
Location, Statement of Financial Position, Balance [Axis]: us-gaap:MarketableSecuritiesCurrent | U.S. Treasury securities | Level 1    
Marketable securities:    
Debt securities 0 0
Location, Statement of Financial Position, Balance [Axis]: us-gaap:MarketableSecuritiesCurrent | U.S. Treasury securities | Level 2    
Marketable securities:    
Debt securities 6,756,734 5,729,892
Location, Statement of Financial Position, Balance [Axis]: us-gaap:MarketableSecuritiesCurrent | U.S. Treasury securities | Level 3    
Marketable securities:    
Debt securities 0 0
Location, Statement of Financial Position, Balance [Axis]: us-gaap:MarketableSecuritiesCurrent | Publicly-traded equity securities    
Marketable securities:    
Publicly-traded equity securities 185,383 23,355
Location, Statement of Financial Position, Balance [Axis]: us-gaap:MarketableSecuritiesCurrent | Publicly-traded equity securities | Level 1    
Marketable securities:    
Publicly-traded equity securities 185,383 23,355
Location, Statement of Financial Position, Balance [Axis]: us-gaap:MarketableSecuritiesCurrent | Publicly-traded equity securities | Level 2    
Marketable securities:    
Publicly-traded equity securities 0 0
Location, Statement of Financial Position, Balance [Axis]: us-gaap:MarketableSecuritiesCurrent | Publicly-traded equity securities | Level 3    
Marketable securities:    
Publicly-traded equity securities 0 0
Location, Statement of Financial Position, Balance [Axis]: us-gaap:PrepaidExpenseAndOtherAssetsCurrent | Certificates of deposit    
Prepaid expenses and other current assets and other assets:    
Certificates of deposit 4,860 4,846
Location, Statement of Financial Position, Balance [Axis]: us-gaap:PrepaidExpenseAndOtherAssetsCurrent | Certificates of deposit | Level 1    
Prepaid expenses and other current assets and other assets:    
Certificates of deposit 0 0
Location, Statement of Financial Position, Balance [Axis]: us-gaap:PrepaidExpenseAndOtherAssetsCurrent | Certificates of deposit | Level 2    
Prepaid expenses and other current assets and other assets:    
Certificates of deposit 4,860 4,846
Location, Statement of Financial Position, Balance [Axis]: us-gaap:PrepaidExpenseAndOtherAssetsCurrent | Certificates of deposit | Level 3    
Prepaid expenses and other current assets and other assets:    
Certificates of deposit $ 0 $ 0