The net carrying values of Ciena’s convertible notes payable was comprised of the following for the fiscal periods indicated (in thousands): | | | | | | | | | | | | October 31, 2018 | | October 31, 2017 | 3.75% Convertible Senior Notes due October 15, 2018 (Original) | | $ | — |
| | $ | 61,071 |
| 3.75% Convertible Senior Notes due October 15, 2018 (New) | | — |
| | 287,221 |
| 4.0% Convertible Senior Notes due December 15, 2020 | | — |
| | 194,717 |
| | | $ | — |
| | $ | 543,009 |
|
The net carrying values of Ciena’s term loans were comprised of the following for the fiscal periods indicated (in thousands): | | | | | | | | | | | | October 31, 2018 | | October 31, 2017 | Term Loan Payable due January 30, 2022 | | $ | — |
| | $ | 392,972 |
| Term Loan Payable due September 28, 2025 | | 693,450 |
| | — |
| | | $ | 693,450 |
| | $ | 392,972 |
|
The following table sets forth the carrying value and the estimated fair value of Ciena’s 2025 Term Loan (in thousands): | | | | | | | | | | | | October 31, 2018 | | | Carrying Value(1) | | Fair Value(2) | Term Loan Payable due September 28, 2025 | | $ | 693,450 |
| | $ | 702,625 |
|
| | (1) | Includes unamortized debt discount and debt issuance costs. |
| | (2) | Ciena’s term loan is categorized as Level 2 in the fair value hierarchy. Ciena estimated the fair value of its 2025 Term Loan using a market approach based upon observable inputs, such as current market transactions involving comparable securities. |
|