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Debt - 2028 Convertible Notes (Details)		3 Months Ended
	Mar. 16, 2021 USD ($) d $ / shares	Mar. 31, 2021 USD ($) $ / shares	Mar. 31, 2020 USD ($)	Dec. 31, 2020 USD ($) $ / shares
Class A voting common stock
Debt Instrument [Line Items]
Common stock, par value (in usd per share) | $ / shares		$ 0.001		$ 0.001
2028 Convertible Notes
Debt Instrument [Line Items]
Principal		$ 250,000,000		$ 0
Conversion option		66,908,000	$ 0
Issuance costs			$ 0
2028 Convertible Notes | Class A voting common stock
Debt Instrument [Line Items]
Common stock, par value (in usd per share) | $ / shares	$ 0.001
2028 Convertible Notes | Convertible notes
Debt Instrument [Line Items]
Principal	$ 250,000,000
Stated rate	0.50%
Total net proceeds	$ 216,845,000
Conversion ratio	5.5781
Conversion price (usd per share) | $ / shares	$ 179.27
Cash redemption price, percent	100.00%
Conversion option	$ 66,908,000
Effective interest rate	5.125%
Carrying amount of equity component	$ 39,359,000
Annual effective interest rate	4.966%
Issuance costs attributable to the liability component	$ 5,607,000
Issuance costs	$ 2,049,000	$ 2,049,000
2028 Convertible Notes | Convertible notes | Conversion option 1
Debt Instrument [Line Items]
Trading days | d	20
Consecutive trading days | d	30
2028 Convertible Notes | Convertible notes | Conversion option 1 | Class A voting common stock
Debt Instrument [Line Items]
Stock price trigger percent	130.00%
2028 Convertible Notes | Convertible notes | Conversion option 2
Debt Instrument [Line Items]
Consecutive trading days | d	10
Consecutive business days | d	5
2028 Convertible Notes | Convertible notes | Conversion option 2 | Class A voting common stock
Debt Instrument [Line Items]
Stock price trigger percent	98.00%

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