v3.20.1

Subsequent Events (Details)			3 Months Ended
	May 01, 2020 USD ($)	Apr. 23, 2020 USD ($) day $ / shares	Jun. 30, 2020 USD ($)	Apr. 29, 2020 USD ($)	Mar. 31, 2020 $ / shares	Dec. 31, 2019 $ / shares
Subsequent Event [Line Items]
Common stock, par value (in dollars per share) | $ / shares					$ 0.001	$ 0.001
The Notes | Convertible Debt | Subsequent Event
Subsequent Event [Line Items]
Aggregate principal amount		$ 330,000,000
Debt instrument, optional increase in face amount		50,000,000		$ 50,000,000.0
Proceeds from issuance of debt		$ 321,800,000
Interest rate		2.25%
Common stock, par value (in dollars per share) | $ / shares		$ 0.001
Debt instrument, convertible, threshold percentage of stock price trigger		130.00%
Debt instrument, convertible, threshold trading days | day		20
Debt instrument, convertible, threshold consecutive trading days | day		30
Debt instrument, convertible, threshold consecutive trading days, sale price per share | day		5
Debt instrument, convertible, measurement period | day		10
Debt instrument, threshold percentage of sales price per share		98.00%
Debt instrument, convertible, conversion ratio		0.0353773
Debt instrument, convertible, conversion price (in dollars per share) | $ / shares		$ 28.27
Capped call, cap price (in dollars per share) | $ / shares		$ 44.34
Cost of capped call transaction		$ 43,900,000
Forecast | The Notes | Convertible Debt
Subsequent Event [Line Items]
Proceeds from issuance of debt	$ 48,800,000
Gain (loss) on extinguishment of debt			$ (12,000,000)

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