Cash Equivalents and Investments - Schedule of Debt Securities, Available-for-Sale, Unrealized Loss Position, Fair Value (Details) $ in Thousands	Sep. 30, 2023 USD ($)
Debt Securities, Available-for-Sale, Unrealized Loss Position [Line Items]
Less than 12 Months, Fair Value	$ 1,891,328
Less than 12 Months, Unrealized Losses	(16,551)
12 Months or Greater, Fair Value	0
12 Months or Greater, Unrealized Losses	0
Total, Fair Value	1,891,328
Total, Unrealized Losses	(16,551)
U.S. Treasury securities
Debt Securities, Available-for-Sale, Unrealized Loss Position [Line Items]
Less than 12 Months, Fair Value	1,293,384
Less than 12 Months, Unrealized Losses	(10,181)
12 Months or Greater, Fair Value	0
12 Months or Greater, Unrealized Losses	0
Total, Fair Value	1,293,384
Total, Unrealized Losses	(10,181)
U.S. agency securities
Debt Securities, Available-for-Sale, Unrealized Loss Position [Line Items]
Less than 12 Months, Fair Value	213,444
Less than 12 Months, Unrealized Losses	(623)
12 Months or Greater, Fair Value	0
12 Months or Greater, Unrealized Losses	0
Total, Fair Value	213,444
Total, Unrealized Losses	(623)
Foreign government securities
Debt Securities, Available-for-Sale, Unrealized Loss Position [Line Items]
Less than 12 Months, Fair Value	9,043
Less than 12 Months, Unrealized Losses	(161)
12 Months or Greater, Fair Value	0
12 Months or Greater, Unrealized Losses	0
Total, Fair Value	9,043
Total, Unrealized Losses	(161)
Corporate debt securities
Debt Securities, Available-for-Sale, Unrealized Loss Position [Line Items]
Less than 12 Months, Fair Value	375,457
Less than 12 Months, Unrealized Losses	(5,586)
12 Months or Greater, Fair Value	0
12 Months or Greater, Unrealized Losses	0
Total, Fair Value	375,457
Total, Unrealized Losses	$ (5,586)