First Trust NYSE Arca Biotechnology Index Fund Annual Total Returns |
12 Months Ended | |||||||||
|---|---|---|---|---|---|---|---|---|---|---|
Dec. 31, 2025 |
Dec. 31, 2024 |
Dec. 31, 2023 |
Dec. 31, 2022 |
Dec. 31, 2021 |
Dec. 31, 2020 |
Dec. 31, 2019 |
Dec. 31, 2018 |
Dec. 31, 2017 |
Dec. 31, 2016 |
|
| First Trust NYSE Arca Biotechnology Index Fund | First Trust NYSE Arca Biotechnology Index Fund | ||||||||||
| Prospectus [Line Items] | ||||||||||
| Annual Return [Percent] | 24.09% | 5.76% | 2.26% | (4.60%) | (3.64%) | 12.93% | 19.78% | (0.21%) | 36.99% | (19.60%) |