Fair Value of Financial Instruments - Measured on Recurring Basis (Details) - USD ($) $ in Thousands	Sep. 30, 2022	Dec. 31, 2021
Assets:
Derivative Asset, Statement of Financial Position		Convertible note hedges
Liabilities:
Derivative Liability, Statement of Financial Position	Note hedge warrants	Note hedge warrants
Recurring basis
Assets:
Convertible note hedges		$ 1,115
Total assets measured at fair value	$ 559,909	598,083
Liabilities:
Note hedge warrants	1	1,316
Total liabilities measured at fair value	1	1,316
Recurring basis | Money market funds
Assets:
Cash and cash equivalents	130,674	595,233
Restricted cash	1,735	1,735
Recurring basis | Repurchase agreements
Assets:
Cash and cash equivalents	268,000
Recurring basis | Commercial paper
Assets:
Cash and cash equivalents	156,213
Recurring basis | Quoted Prices in Active Markets for Identical Assets (Level 1)
Assets:
Total assets measured at fair value	132,409	596,968
Recurring basis | Quoted Prices in Active Markets for Identical Assets (Level 1) | Money market funds
Assets:
Cash and cash equivalents	130,674	595,233
Restricted cash	1,735	1,735
Recurring basis | Significant Other Observable Inputs (Level 2)
Assets:
Total assets measured at fair value	427,500
Recurring basis | Significant Other Observable Inputs (Level 2) | Repurchase agreements
Assets:
Cash and cash equivalents	268,000
Recurring basis | Significant Other Observable Inputs (Level 2) | Commercial paper
Assets:
Cash and cash equivalents	156,213
Recurring basis | Significant Unobservable Inputs (Level 3)
Assets:
Convertible note hedges		1,115
Total assets measured at fair value		1,115
Liabilities:
Note hedge warrants	1	1,316
Total liabilities measured at fair value	$ 1	$ 1,316