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v3.21.2

Debt (Details) $ / shares in Units, shares in Thousands |  | 1 Months Ended | 3 Months Ended | 9 Months Ended |  |
--- | --- | --- | --- | --- | --- | ---
Mar. 31, 2021 USD ($) $ / shares | Apr. 30, 2020 USD ($) D | Sep. 30, 2021 USD ($) $ / shares shares | Sep. 30, 2020 USD ($) | Sep. 30, 2021 USD ($) $ / shares shares | Sep. 30, 2020 USD ($) | Dec. 31, 2020 USD ($) $ / shares shares | Sep. 30, 2015 USD ($)
Debt Instrument [Line Items] |  |  |  |  |  |  |  |
Proceeds from Convertible Note, net of issuance costs |  |  |  |  |  | $ 278,316,000 |  |
Common Stock, Par or Stated Value Per Share | $ / shares |  |  | $ 0.0001 |  | $ 0.0001 |  | $ 0.0001 |
Common stock, shares issued | shares |  |  | 94,538 |  | 94,538 |  | 86,223 |
Accrued Interest |  |  | $ 2,695,000 |  | $ 2,695,000 |  | $ 1,078,000 |
Amortization of debt discount and issuance cost |  |  |  |  | 917,000 | 149,000 |  |
Interest expense |  |  | 2,078,000 | $ 4,270,000 | 6,226,000 | 10,772,000 |  |
Convertible Notes |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |
Aggregate principal amount |  | $ 287,500,000 | 287,500,000 |  | $ 287,500,000 |  |  |
Proceeds from Convertible Note, net of issuance costs |  | $ 278,300,000 |  |  |  |  |  |
Per annum interest rate (as a percent) |  | 2.25% |  |  | 2.25% |  |  |
Interest expense |  |  | $ 1,925,000 |  | $ 5,769,000 |  |  |
Common Stock, Par or Stated Value Per Share | $ / shares | $ 0.0001 |  |  |  |  |  |  |
Debt instrument, term |  |  |  |  | 7 years |  |  |
Effective interest rate (as a percent) |  |  | 2.72% |  | 2.72% |  |  |
Principal amount per convertible note |  | $ 1,000 |  |  |  |  |  |
Number of threshold consecutive trading days | D |  | 30 |  |  |  |  |  |
Threshold business days | D |  | 5 |  |  |  |  |  |
Conversion price (in dollars per share) | $ / shares | $ 38.79 |  |  |  |  |  |  |
Initial conversion rate | 25.7785 |  |  |  |  |  |  |
Convertible to shares of common stock | 7,411,704 |  |  |  |  |  |  |
Percentage of principal amount converted | 100.00% |  |  |  |  |  |  |
Carrying value |  |  | $ 280,085,000 |  | $ 280,085,000 |  |  |
Convertible Notes | Accounting Standards Update 2020-06 |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |
Carrying value |  |  |  |  |  |  | $ 279,167,000 |
5 consecutive trading day period | Convertible Notes |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |
Threshold trading days | D |  | 5 |  |  |  |  |  |
Percentage of conversion price |  | 98.00% |  |  |  |  |  |
20 trading days period | Convertible Notes |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |
Threshold trading days | D |  | 20 |  |  |  |  |  |
Percentage of conversion price |  | 130.00% |  |  |  |  |  |
Redeemable for cash on or after May 2024 |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |
Number of threshold consecutive trading days | D |  | 20 |  |  |  |  |  |
Threshold trading days | D |  | 30 |  |  |  |  |  |
Percentage of conversion price |  | 130.00% |  |  |  |  |  |
Percentage of principal amount converted |  | 100.00% |  |  |  |  |  |
Level 2 |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |
Fair value of liability |  |  | 863,300,000 |  | 863,300,000 |  |  |
Line Of Credit-UBS |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |
Maximum borrowing capacity |  |  |  |  |  |  |  | $ 50,000,000.0
Outstanding balance |  |  | $ 50,000,000.0 |  | 50,000,000.0 |  |  |
Interest expense |  |  |  | $ 200,000 | $ 500,000 | $ 700,000 |  |
Line Of Credit-UBS | LIBOR |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |
Spread on interest rate (as a percent) |  |  |  |  | 1.10% |  |  |
2017 Term Loan |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |
Debt, repayment amount |  | $ 79,200,000 |  |  |  |  |  |

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