Long-term Debt - Convertible Senior Notes Carrying Value (Details) - Senior Notes - USD ($) |
12 Months Ended | ||||||
---|---|---|---|---|---|---|---|
Dec. 31, 2020 |
Dec. 31, 2019 |
Aug. 31, 2020 |
Oct. 31, 2018 |
Oct. 24, 2018 |
Oct. 22, 2018 |
Dec. 31, 2016 |
|
2024 Notes | |||||||
Debt Instrument [Line Items] | |||||||
Carrying value | $ 81,462,000 | $ 0 | |||||
Unamortized debt discount and issuance costs | 35,589,000 | 0 | |||||
Principal amount | $ 117,051,000 | 0 | $ 117,100,000 | ||||
Remaining amortization period (years) | 3 years 10 months 24 days | ||||||
2024 Notes | Level 2 | |||||||
Debt Instrument [Line Items] | |||||||
Fair value | $ 153,220,000 | 0 | |||||
2025 Notes | |||||||
Debt Instrument [Line Items] | |||||||
Carrying value | 116,349,000 | 107,169,000 | |||||
Unamortized debt discount and issuance costs | 56,151,000 | 65,331,000 | |||||
Principal amount | $ 172,500,000 | $ 172,500,000 | $ 172,500,000 | $ 22,500,000 | $ 150,000,000.0 | ||
Remaining amortization period (years) | 4 years 9 months 18 days | 5 years 9 months 18 days | |||||
2025 Notes | Level 2 | |||||||
Debt Instrument [Line Items] | |||||||
Fair value | $ 147,488,000 | $ 122,048,000 | |||||
2021 Notes | |||||||
Debt Instrument [Line Items] | |||||||
Carrying value | 26,557,000 | 123,237,000 | |||||
Unamortized debt discount and issuance costs | 180,000 | 1,763,000 | |||||
Principal amount | $ 26,737,000 | $ 125,000,000 | $ 125,000,000.0 | ||||
Remaining amortization period (years) | 10 months 24 days | 1 year 10 months 24 days | |||||
2021 Notes | Level 2 | |||||||
Debt Instrument [Line Items] | |||||||
Fair value | $ 26,470,000 | $ 111,250,000 |