v3.21.2

Convertible Senior Notes (Tables) | 9 Months Ended
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Sep. 30, 2021
Debt Disclosure [Abstract] |
Summary of Convertible Notes | The outstanding 2023 Notes consist of the following:
|  | As of September 30, 2021 |  | As of December 31, 2020
Liability component: |  |  |  |
Principal |  | $ | 10,909 |  |  | $ | 48,035 |
Unamortized debt discount |  | (765) |  |  | (4,915) |
Unamortized debt issuance costs |  | (76) |  |  | (501) |
Net carrying amount |  | 10,068 |  |  | 42,619 |
Equity component: |  |  |  |
Net carrying amount |  | $ | 2,321 |  |  | $ | 10,217 |
The outstanding 2026 Notes consist of the following:
|  | As of September 30, 2021 |  | As of December 31, 2020
Liability component: |  |  |  |
Principal |  | $ | 316,250 |  |  | $ | 316,250 |
Unamortized debt discount |  | (59,756) |  |  | (67,977) |
Unamortized debt issuance costs |  | (4,489) |  |  | (5,114) |
Net carrying amount |  | 252,005 |  |  | 243,159 |
Equity component: |  |  |  |
Net carrying amount |  | $ | 81,550 |  |  | $ | 81,550 |
The outstanding 2025 Notes consist of the following:
|  | As of September 30, 2021 |  | As of December 31, 2020
Liability component: |  |  |  |
Principal |  | $ | 350,000 |  |  | $ | 350,000 |
Unamortized debt discount |  | (62,894) |  |  | (73,075) |
Unamortized debt issuance costs |  | (4,476) |  |  | (5,235) |
Net carrying amount |  | 282,630 |  |  | 271,690 |
Equity component: |  |  |  |
Net carrying amount |  | $ | 73,109 |  |  | $ | 73,097 |
Summary of Interest Expense | The following table sets forth total interest expense recognized related to the 2023 Notes:
|  | Three Months Ended September 30, |  | Nine Months Ended September 30,
|  | 2021 |  | 2020 |  | 2021 |  | 2020
Contractual interest expense |  | $ | 20 |  |  | $ | 431 |  |  | $ | 172 |  |  | $ | 1,294 |
Amortization of debt issuance costs |  | 45 |  |  | 276 |  |  | 197 |  |  | 819 |
Amortization of debt discount |  | 127 |  |  | 2,506 |  |  | 1,088 |  |  | 7,422 |
Total |  | $ | 192 |  |  | $ | 3,213 |  |  | $ | 1,457 |  |  | $ | 9,535 |
The following table sets forth total interest expense recognized related to the 2026 Notes:
|  | Three Months Ended September 30, |  | Nine Months Ended September 30,
|  | 2021 |  | 2020 |  | 2021 |  | 2020
Contractual interest expense |  | $ | 593 |  |  | $ | 593 |  |  | 1,779 |  |  | $ | 1,772 |
Amortization of debt issuance costs |  | 219 |  |  | 206 |  |  | 636 |  |  | 608 |
Amortization of debt discount |  | 2,801 |  |  | 2,698 |  |  | 8,188 |  |  | 7,959 |
Total |  | $ | 3,613 |  |  | $ | 3,497 |  |  | $ | 10,603 |  |  | $ | 10,339 |
The following table sets forth total interest expense recognized related to the 2025 Notes:
|  | Three Months Ended |  | Nine Months Ended |  |
|  | September 30, 2021 |  | September 30, 2021 |  |  |  |
Contractual interest expense |  | $ | 109 |  |  | $ | 327 |  |  |  |  |
Amortization of debt issuance costs |  | 241 |  |  | 717 |  |  |  |  |
Amortization of debt discount |  | 3,416 |  |  | 10,122 |  |  |  |  |
Total |  | $ | 3,766 |  |  | $ | 11,166 |  |  |  |  |

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- Definition Tabular disclosure of information pertaining to short-term and long-debt instruments or arrangements, including but not limited to identification of terms, features, collateral requirements and other information necessary to a fair presentation. + References No definition available. + Details
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