S000000584 [Member] Annual Total Returns - BARON SMALL CAP FUND |
12 Months Ended | ||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|
Sep. 30, 2025 |
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 |
|
| Prospectus [Line Items] | |||||||||||
| Annual Return Caption [Text] | Average Annual Total Returns for the periods ended December 31, 2025 | ||||||||||
| BARON SMALL CAP FUND | |||||||||||
| Prospectus [Line Items] | |||||||||||
| Annual Return [Percent] | (0.90%) | 13.28% | 26.88% | (31.22%) | 15.53% | 40.33% | 34.50% | (7.39%) | 27.13% | 9.94% | |