Performance Management |
Feb. 28, 2026 |
|---|---|
| PRIMECAP Odyssey Stock Fund Series | |
| Prospectus [Line Items] | |
| Bar Chart and Performance Table [Heading] | Fund Performance |
| Performance Narrative [Text Block] | The following performance information indicates some of the risks of investing in the Fund by showing changes in the Fund’s performance over time. The bar chart below illustrates the Fund’s total return for each of the last ten calendar years. The table below illustrates the Fund’s average annual return over time compared with a domestic broad-based securities market index. The Fund’s past performance, before and after taxes, is not necessarily an indication of how the Fund will perform in the future. Unlike the Fund’s returns, the index returns do not reflect any deductions for fees, expenses, or taxes. For additional information on the index, please see “Index Description” on page 42 of the statutory prospectus. Updated performance is available on the Fund’s website at www.primecap.com.
|
| Performance Past Does Not Indicate Future [Text] | The Fund’s past performance, before and after taxes, is not necessarily an indication of how the Fund will perform in the future. |
| Performance Information Illustrates Variability of Returns [Text] | The following performance information indicates some of the risks of investing in the Fund by showing changes in the Fund’s performance over time. |
| Bar Chart [Heading] | Calendar Year Total Return |
| Bar Chart Closing [Text Block] | During the period shown in the bar chart, the Fund’s highest quarterly return was +17.39% for the quarter ended December 31, 2020, and the lowest quarterly return was -25.66% for the quarter ended March 31, 2020.
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| Highest Quarterly Return, Label [Optional Text] | highest quarterly return |
| Highest Quarterly Return | 17.39% |
| Highest Quarterly Return, Date | Dec. 31, 2020 |
| Lowest Quarterly Return, Label [Optional Text] | lowest quarterly return |
| Lowest Quarterly Return | (25.66%) |
| Lowest Quarterly Return, Date | Mar. 31, 2020 |
| Performance Table Heading | Average Annual Total Returns as of December 31, 2025 |
| Performance Table Uses Highest Federal Rate | After-tax returns are calculated using the historical highest individual federal marginal income tax rates and do not reflect the impact of state and local taxes. |
| Performance Table Not Relevant to Tax Deferred | Actual after-tax returns depend on an investor’s tax situation and may differ from those shown, and after-tax returns shown may not be relevant to investors who hold their Fund shares through tax-advantaged arrangements, such as 401(k) plans or individual retirement accounts (“IRAs”).The “Return After Taxes on Distributions and Sale of Fund Shares” is higher than other return figures when a capital loss occurs upon the redemption of Fund shares. |
| Index No Deduction for Fees, Expenses, or Taxes [Text] | (reflects no deduction for fees, expenses, or taxes) |
| Performance Table Closing [Text Block] | After-tax returns are calculated using the historical highest individual federal marginal income tax rates and do not reflect the impact of state and local taxes. Actual after-tax returns depend on an investor’s tax situation and may differ from those shown, and after-tax returns shown may not be relevant to investors who hold their Fund shares through tax-advantaged arrangements, such as 401(k) plans or individual retirement accounts (“IRAs”). The “Return After Taxes on Distributions and Sale of Fund Shares” is higher than other return figures when a capital loss occurs upon the redemption of Fund shares.
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| Performance Availability Website Address [Text] | www.primecap.com |
| PRIMECAP Odyssey Growth Fund Series | |
| Prospectus [Line Items] | |
| Bar Chart and Performance Table [Heading] | Fund Performance |
| Performance Narrative [Text Block] | The following performance information indicates some of the risks of investing in the Fund by showing changes in the Fund’s performance over time. The bar chart below illustrates the Fund’s total return for each of the last ten calendar years. The table below illustrates the Fund’s average annual return over time compared with a domestic broad-based securities market index. The Fund’s past performance, before and after taxes, is not necessarily an indication of how the Fund will perform in the future. Unlike the Fund’s returns, the index returns do not reflect any deductions for fees, expenses, or taxes. For additional information on the index, please see “Index Description” on page 42 of the statutory prospectus. Updated performance is available on the Fund’s website at www.primecap.com.
|
| Performance Past Does Not Indicate Future [Text] | The Fund’s past performance, before and after taxes, is not necessarily an indication of how the Fund will perform in the future. |
| Performance Information Illustrates Variability of Returns [Text] | The following performance information indicates some of the risks of investing in the Fund by showing changes in the Fund’s performance over time. |
| Bar Chart [Heading] | Calendar Year Total Return |
| Bar Chart Closing [Text Block] | During the period shown in the bar chart, the Fund’s highest quarterly return was +23.61% for the quarter ended June 30, 2020, and the lowest quarterly return was -23.77% for the quarter ended March 31, 2020.
|
| Highest Quarterly Return, Label [Optional Text] | highest quarterly return |
| Highest Quarterly Return | 23.61% |
| Highest Quarterly Return, Date | Jun. 30, 2020 |
| Lowest Quarterly Return, Label [Optional Text] | lowest quarterly return |
| Lowest Quarterly Return | (23.77%) |
| Lowest Quarterly Return, Date | Mar. 31, 2020 |
| Performance Table Heading | Average Annual Total Returns as of December 31, 2025 |
| Performance Table Uses Highest Federal Rate | After-tax returns are calculated using the historical highest individual federal marginal income tax rates and do not reflect the impact of state and local taxes. |
| Performance Table Not Relevant to Tax Deferred | Actual after-tax returns depend on an investor’s tax situation and may differ from those shown, and after-tax returns shown may not be relevant to investors who hold their Fund shares through tax-advantaged arrangements, such as 401(k) plans or individual retirement accounts (“IRAs”). |
| Performance Table Explanation after Tax Higher | The “Return After Taxes on Distributions and Sale of Fund Shares” is higher than other return figures when a capital loss occurs upon the redemption of Fund shares. |
| Index No Deduction for Fees, Expenses, or Taxes [Text] | (reflects no deduction for fees, expenses, or taxes) |
| Performance Table Closing [Text Block] | After-tax returns are calculated using the historical highest individual federal marginal income tax rates and do not reflect the impact of state and local taxes. Actual after-tax returns depend on an investor’s tax situation and may differ from those shown, and after-tax returns shown may not be relevant to investors who hold their Fund shares through tax-advantaged arrangements, such as 401(k) plans or individual retirement accounts (“IRAs”). The “Return After Taxes on Distributions and Sale of Fund Shares” is higher than other return figures when a capital loss occurs upon the redemption of Fund shares.
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| Performance Availability Website Address [Text] | www.primecap.com |
| PRIMECAP Odyssey Aggressive Growth Fund Series | |
| Prospectus [Line Items] | |
| Bar Chart and Performance Table [Heading] | Fund Performance |
| Performance Narrative [Text Block] | The following performance information indicates some of the risks of investing in the Fund by showing changes in the Fund’s performance over time. The bar chart below illustrates the Fund’s total return for each of the last ten calendar years. The table below illustrates the Fund’s average annual return over time compared with a domestic broad-based securities market index. The Fund’s past performance, before and after taxes, is not necessarily an indication of how the Fund will perform in the future. Unlike the Fund’s returns, the index returns do not reflect any deductions for fees, expenses, or taxes. For additional information on the index, please see “Index Description” on page 42 of the statutory prospectus. Updated performance is available on the Fund’s website at www.primecap.com.
|
| Performance Past Does Not Indicate Future [Text] | The Fund’s past performance, before and after taxes, is not necessarily an indication of how the Fund will perform in the future. |
| Performance Information Illustrates Variability of Returns [Text] | The following performance information indicates some of the risks of investing in the Fund by showing changes in the Fund’s performance over time. |
| Bar Chart [Heading] | Calendar Year Total Return |
| Bar Chart Closing [Text Block] | During the period shown in the bar chart, the Fund’s highest quarterly return was +28.84% for the quarter ended June 30, 2020, and the lowest quarterly return was -22.47% for the quarter ended March 31, 2020.
|
| Highest Quarterly Return, Label [Optional Text] | highest quarterly return |
| Highest Quarterly Return | 28.84% |
| Highest Quarterly Return, Date | Jun. 30, 2020 |
| Lowest Quarterly Return, Label [Optional Text] | lowest quarterly return |
| Lowest Quarterly Return | (22.47%) |
| Lowest Quarterly Return, Date | Mar. 31, 2020 |
| Performance Table Heading | Average Annual Total Returns as of December 31, 2025 |
| Performance Table Uses Highest Federal Rate | After-tax returns are calculated using the historical highest individual federal marginal income tax rates and do not reflect the impact of state and local taxes. |
| Performance Table Not Relevant to Tax Deferred | Actual after-tax returns depend on an investor’s tax situation and may differ from those shown, and after-tax returns shown may not be relevant to investors who hold their Fund shares through tax-advantaged arrangements, such as 401(k) plans or individual retirement accounts (“IRAs”). |
| Performance Table Explanation after Tax Higher | The “Return After Taxes on Distributions and Sale of Fund Shares” is higher than other return figures when a capital loss occurs upon the redemption of Fund shares. |
| Index No Deduction for Fees, Expenses, or Taxes [Text] | (reflects no deduction for fees, expenses, or taxes) |
| Performance Table Closing [Text Block] | After-tax returns are calculated using the historical highest individual federal marginal income tax rates and do not reflect the impact of state and local taxes. Actual after-tax returns depend on an investor’s tax situation and may differ from those shown, and after-tax returns shown may not be relevant to investors who hold their Fund shares through tax-advantaged arrangements, such as 401(k) plans or individual retirement accounts (“IRAs”). The “Return After Taxes on Distributions and Sale of Fund Shares” is higher than other return figures when a capital loss occurs upon the redemption of Fund shares.
|
| Performance Availability Website Address [Text] | www.primecap.com |