v3.20.2

Convertible Senior Notes - Additional Information (Details) shares in Millions | 3 Months Ended | 6 Months Ended |  |  |
--- | --- | --- | --- | --- | ---
Sep. 30, 2020 USD ($) | Jun. 30, 2020 USD ($) shares | Jun. 30, 2019 shares | Jun. 30, 2020 USD ($) day trading_day shares | Jun. 30, 2019 shares | Dec. 31, 2019 USD ($) | Jun. 30, 2017 USD ($) | Nov. 30, 2013 USD ($)
Debt Instrument [Line Items] |  |  |  |  |  |  |  |
Percentage of purchase price of notes which should be paid upon fundamental change (percent) |  |  |  | 100.00% |  |  |  |
Benefit from exercise of 2022 Note Hedge |  | $ 18,312,000 |  | $ 21,864,000 |  |  |  |
Estimated fair value of the note based on the closing trading price |  | $ 100 |  | $ 100 |  | $ 100 |  |
Warrant exercise period | trading_day |  |  |  | 60 |  |  |  |
2022 Warrants |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |
Number of potential securities issued upon automatic exercise of the Warrants (in shares) | shares |  | 2.9 |  | 2.9 |  |  |  |
2018 Warrants |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |
Number of shares to be issued upon exercise of the Warrants (in shares) | shares |  |  | 1.6 |  | 4.3 |  |  |
Stock Price Trigger Measurement |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |
Trading days threshold | day |  |  |  | 20 |  |  |  |
Consecutive trading days threshold, total | day |  |  |  | 30 |  |  |  |
Threshold percentage of stock price trigger (percent) |  |  |  | 130.00% |  |  |  |
Notes Price Trigger Measurement |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |
Trading days threshold | day |  |  |  | 5 |  |  |  |
Consecutive trading days threshold, total | day |  |  |  | 5 |  |  |  |
Threshold percentage of stock price trigger (percent) |  |  |  | 98.00% |  |  |  |
Conversion of notes base conversion price |  |  |  | $ 1,000 |  |  |  |
2022 Notes |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |
Face amount of debt |  | $ 764,778,000 |  | 764,778,000 |  | $ 782,491,000 | $ 782,500,000 |
Stated interest rate |  |  |  |  |  |  | 0.00% |
Cash paid for settlement of debt |  |  |  | 18,000,000 |  |  |  |
Fair value adjustments |  |  |  | 23,000,000 |  |  |  |
Benefit from exercise of 2022 Note Hedge |  |  |  | $ 22,000,000 |  |  |  |
Remaining discount amortization period |  |  |  | 23 months |  |  |  |
2022 Notes | Forecast |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |
Cash paid for settlement of debt | $ 23,000,000 |  |  |  |  |  |  |
2018 Notes |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |
Face amount of debt |  |  |  |  |  |  |  | $ 575,000,000
Stated interest rate |  |  |  |  |  |  |  | 0.00%

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