Shareholder Report, Average Annual Return (Details) |
12 Months Ended | 60 Months Ended | 120 Months Ended | ||
|---|---|---|---|---|---|
Jul. 31, 2025 |
Jul. 31, 2025 |
Jul. 31, 2025 |
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| C000009521 [Member] | |||||
| Average Annual Return [Line Items] | |||||
| Line Graph and Table Measure Name | Davis Research Fund (Class A) — With sales charge | ||||
| Average Annual Return, Percent | [1] | 13.40% | 12.09% | 11.17% | |
| Without Sales Load [Member] | C000009521 [Member] | |||||
| Average Annual Return [Line Items] | |||||
| Line Graph and Table Measure Name | Davis Research Fund (Class A) — Without sales charge | ||||
| Average Annual Return, Percent | 19.06% | 13.18% | 11.71% | ||
| Standard & Poor's 500 Index [Member] | |||||
| Average Annual Return [Line Items] | |||||
| Line Graph and Table Measure Name | S&P 500 Index | ||||
| Average Annual Return, Percent | 16.33% | 15.87% | 13.65% | ||
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