Shareholder Report, Line Graph (Details) - USD ($) |
12 Months Ended | 24 Months Ended | 36 Months Ended | 48 Months Ended | 60 Months Ended | 72 Months Ended | 84 Months Ended | 96 Months Ended | 108 Months Ended | 120 Months Ended | ||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
Jul. 31, 2016 |
Jul. 31, 2026 |
Jul. 31, 2017 |
Jul. 31, 2018 |
Jul. 31, 2019 |
Jul. 31, 2020 |
Jul. 31, 2021 |
Jul. 31, 2022 |
Jul. 31, 2023 |
Jul. 31, 2024 |
Jul. 31, 2025 |
Jul. 31, 2026 |
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| C000009521 [Member] | ||||||||||||||
| Account Value [Line Items] | ||||||||||||||
| Line Graph and Table Measure Name | Davis Research Fund (Class A) — With sales charge | |||||||||||||
| Accumulated Value | [1] | $ 9,525 | $ 11,703 | $ 13,451 | $ 13,713 | $ 15,567 | $ 20,286 | $ 17,100 | $ 20,475 | $ 24,295 | $ 28,925 | $ 36,280 | ||
| Standard & Poor's 500 Index [Member] | ||||||||||||||
| Account Value [Line Items] | ||||||||||||||
| Line Graph and Table Measure Name | S&P 500 Index | |||||||||||||
| Accumulated Value | $ 10,000 | $ 11,604 | $ 13,488 | $ 14,566 | $ 16,308 | $ 22,253 | $ 21,220 | $ 23,983 | $ 29,295 | $ 34,079 | $ 40,747 | |||
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