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Description of Business (Details) - USD ($) $ / shares in Units, $ in Thousands		1 Months Ended	3 Months Ended	9 Months Ended
	Jul. 02, 2021	Jul. 31, 2021	Sep. 30, 2021	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020
Subsidiary, Sale of Stock [Line Items]
Common stock par value (in dollars per share)	$ 0.001		$ 0.001	$ 0.001		$ 0.001
Net proceeds	$ 666,900
Payment of stock issuance costs	$ 5,600			$ 5,634	$ 0
Repayment of term loan				$ 524,300	$ 4,012
Conversion of redeemable convertible preferred stock to common stock in connection with initial public offering			$ 70,905
Common stock shares authorized (in shares)	1,000,000,000		1,000,000,000	1,000,000,000		264,720,000
Preferred stock shares authorized (in shares)	100,000,000		100,000	100,000
Preferred stock par value (in dollars per share)	$ 0.001		$ 0.001	$ 0.001
2018 Term Loan
Subsidiary, Sale of Stock [Line Items]
Repayment of term loan	$ 521,600	$ 521,600
Series A Redeemable Convertible Preferred Stock
Subsidiary, Sale of Stock [Line Items]
Conversion of redeemable convertible preferred stock to common stock in connection with initial public offering (in shares)	23,081,080		(23,081,000)
Conversion of redeemable convertible preferred stock to common stock in connection with initial public offering	$ 70,900		$ (70,906)
Common Stock
Subsidiary, Sale of Stock [Line Items]
Conversion of redeemable convertible preferred stock to common stock in connection with initial public offering (in shares)	46,162,160		46,162,000
Conversion of redeemable convertible preferred stock to common stock in connection with initial public offering			$ 46
IPO
Subsidiary, Sale of Stock [Line Items]
Shares issued (in shares)	19,121,000
Common stock par value (in dollars per share)	$ 0.001
Price per share (in dollars per share)	$ 28.00
Net proceeds	$ 505,900
Underwriters Option
Subsidiary, Sale of Stock [Line Items]
Shares issued (in shares)	2,868,150
Net proceeds	$ 75,900
Private Placement
Subsidiary, Sale of Stock [Line Items]
Shares issued (in shares)	3,214,285
Net proceeds	$ 85,000