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Debt - 2026 Convertible Notes (Details)		3 Months Ended
	Feb. 28, 2020 USD ($) d $ / shares	Mar. 31, 2021 USD ($) d $ / 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
2026 Convertible Notes
Debt Instrument [Line Items]
Principal		$ 400,000,000		$ 400,000,000
Cash redemption price, percent	100.00%
Conversion option		125,152,000	$ 125,152,000
Issuance costs			$ 3,742,000
2026 Convertible Notes | Class A voting common stock
Debt Instrument [Line Items]
Common stock, par value (in usd per share) | $ / shares	$ 0.001
2026 Convertible Notes | Convertible notes
Debt Instrument [Line Items]
Principal	$ 400,000,000
Stated rate	0.25%
Total net proceeds	$ 344,722,000
Conversion price (usd per share) | $ / shares	$ 91.03
Conversion option	$ 125,160,000
Effective interest rate	6.763%
Carrying amount of equity component	$ 57,491,000
Annual effective interest rate	6.807%
Issuance costs attributable to the liability component	$ 8,217,000
Issuance costs	$ 3,742,000	$ 3,742,000
2026 Convertible Notes | Convertible notes | Conversion option 1
Debt Instrument [Line Items]
Trading days | d	20	20
Consecutive trading days | d	30	30
2026 Convertible Notes | Convertible notes | Conversion option 2
Debt Instrument [Line Items]
Consecutive trading days | d	10
Consecutive business days | d	5
2026 Convertible Notes | Convertible notes | Class A voting common stock
Debt Instrument [Line Items]
Conversion ratio	10.9857
2026 Convertible Notes | Convertible notes | Class A voting common stock | Conversion option 1
Debt Instrument [Line Items]
Stock price trigger percent	130.00%	130.00%
2026 Convertible Notes | Convertible notes | Class A voting common stock | Conversion option 2
Debt Instrument [Line Items]
Stock price trigger percent	98.00%

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Face amount or stated value per share of common stock.

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