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v3.20.2

Debt - Narrative (Details) | 1 Months Ended |  |
--- | --- | --- | ---
Jan. 31, 2018 USD ($) day $ / shares | Jun. 30, 2020 USD ($) | Dec. 31, 2019 USD ($)
Debt Instrument [Line Items] |  |  |
Underwriting discounts and commissions and other offering expenses | $ |  | $ 6,345,000 | $ 7,043,000
1.75 convertible senior notes due 2025 |  |  |
Debt Instrument [Line Items] |  |  |
Initial conversion rate | 0.0255384 |  |
Convertible Notes | 1.75 convertible senior notes due 2025 |  |  |
Debt Instrument [Line Items] |  |  |
Aggregate principal amount | $ | $ 450,000,000.0 |  |
Option to purchase additional debt | $ | 50,000,000.0 |  |
Underwriting discounts and commissions and other offering expenses | $ | 14,200,000 |  |
Net proceeds | $ | $ 435,800,000 |  |
Initial conversion price (in dollars per share) | $ / shares | $ 39.16 |  |
Convertible Notes ($450.0 face value) | $ | $ 309,100,000 |  |
Effective interest rate | 7.60% |  |
Equity component of convertible debt | $ | $ 140,900,000 |  |
Remaining discount amortization period | 4 years 6 months 14 days |  |
Convertible Notes | Conversion Term (i) | 1.75 convertible senior notes due 2025 |  |  |
Debt Instrument [Line Items] |  |  |
Threshold trading days | day | 5 |  |
Threshold consecutive trading days | day | 5 |  |
Threshold percent of stock price trigger | 98.00% |  |
Convertible Notes | Conversion Term (ii) | 1.75 convertible senior notes due 2025 |  |  |
Debt Instrument [Line Items] |  |  |
Threshold trading days | day | 45 |  |
Threshold consecutive trading days | day | 10 |  |
Threshold percent of stock price trigger | 10.00% |  |
Convertible Notes | Conversion Term (iii) | 1.75 convertible senior notes due 2025 |  |  |
Debt Instrument [Line Items] |  |  |
Threshold trading days following fundamental change | day | 30 |  |
Convertible Notes | Conversion Term (iv) | 1.75 convertible senior notes due 2025 |  |  |
Debt Instrument [Line Items] |  |  |
Threshold trading days | day | 20 |  |
Threshold consecutive trading days | day | 30 |  |
Threshold percent of stock price trigger | 130.00% |  |

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