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v3.22.2

Debt (Details) $ / shares in Units, shares in Thousands |  | 1 Months Ended | 3 Months Ended | 6 Months Ended |  |
--- | --- | --- | --- | --- | --- | ---
Apr. 30, 2020 USD ($) $ / shares | Apr. 30, 2020 USD ($) D $ / shares | Jun. 30, 2022 USD ($) $ / shares shares | Jun. 30, 2021 USD ($) | Jun. 30, 2022 USD ($) $ / shares shares | Jun. 30, 2021 USD ($) | Dec. 31, 2021 USD ($) $ / shares shares | Sep. 30, 2015 USD ($)
Debt Instrument [Line Items] |  |  |  |  |  |  |  |
Common Stock, Par or Stated Value Per Share | $ / shares |  |  | $ 0.0001 |  | $ 0.0001 |  | $ 0.0001 |
Common stock, shares issued | shares |  |  | 96,903 |  | 96,903 |  | 95,140 |
Accrued Interest |  |  | $ 1,078,000 |  | $ 1,078,000 |  | $ 1,078,000 |
Amortization of debt discount and issuance cost |  |  |  |  | 625,000 | $ 610,000 |  |
Interest expense |  |  | 2,150,000 | $ 2,075,000 | 4,237,000 | 4,148,000 |  |
Convertible Notes |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |
Aggregate principal amount | $ 287,500,000 | $ 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 |  |  | $ 1,929,000 | 1,923,000 | $ 3,860,000 | 3,844,000 |  |
Common Stock, Par or Stated Value Per Share | $ / shares | $ 0.0001 | $ 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 | $ 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 |  |  | $ 281,020,000 |  | $ 281,020,000 |  | 280,394,000 |
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 | Convertible Notes |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |
Fair value of long-term debt |  |  | 359,600,000 |  | 359,600,000 |  | 715,700,000 |
Line Of Credit-UBS |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |
Maximum borrowing capacity |  |  |  |  |  |  |  | $ 50,000,000.0
Outstanding balance |  |  | 50,100,000 |  | 50,100,000 |  | 50,100,000 |
Interest expense |  |  | 200,000 | $ 200,000 | 300,000 | $ 300,000 |  |
Line Of Credit-UBS | Level 2 |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |
Fair value of long-term debt |  |  | $ 50,100,000 |  | $ 50,100,000 |  | $ 50,100,000 |
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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