| Form N-CSR Cover | 12 Months Ended |
| Dec. 31, 2024 | |
| Shareholder Report [Line Items] | |
| Document Type | N-CSR |
| Amendment Flag | false |
| Registrant Name | PIONEER FUND /MA/ |
| Entity Central Index Key | 0000078713 |
| Entity Investment Company Type | N-1A |
| Document Period End Date | Dec. 31, 2024 |
| Shareholder Report | 12 Months Ended | |
| Dec. 31, 2024 USD ($) Holding | ||
| Shareholder Report [Line Items] | ||
| Document Type | N-CSR | |
| Amendment Flag | false | |
| Registrant Name | PIONEER FUND /MA/ | |
| Entity Central Index Key | 0000078713 | |
| Entity Investment Company Type | N-1A | |
| Document Period End Date | Dec. 31, 2024 | |
| C000011118 [Member] | ||
| Shareholder Report [Line Items] | ||
| Fund Name | Pioneer Fund | |
| Class Name | Class A | |
| Trading Symbol | PIODX | |
| Annual or Semi-Annual Statement [Text Block] | This annual shareholder report contains important information about Pioneer Fund (“Fund”) for the period of January 1, 2024 to December 31, 2024. | |
| Shareholder Report Annual or Semi-Annual | annual shareholder report | |
| Additional Information [Text Block] | You can find additional information about the Fund at https://www.amundi.com/usinvestors/Resources/Shareholder-Reports | |
| Material Fund Change Notice [Text Block] | This report describes changes to the Fund that occurred during the reporting period. | |
| Additional Information Phone Number | 1-800-225-6292 | |
| Additional Information Website | https://www.amundi.com/usinvestors/Resources/Shareholder-Reports | |
| Expenses [Text Block] | What were the Fund costs for the last year? (Based on a hypothetical $10,000 investment) Class Name Costs of a $10,000 investment Costs paid as a percentage of a $10,000 investment Class A $ 0.92 % | |
| Expenses Paid, Amount | $ 102 | |
| Expense Ratio, Percent | 0.92% | |
| Factors Affecting Performance [Text Block] | How did the Fund perform last year and what affected the Fund performance? For the fiscal year ended December 31, 2024, the Fund’s Sector allocation decisions accounted for the Fund’s benchmark relative underperformance; specifically, an overweight to materials, accounted for the majority of the underperformance. In addition, the Portfolio’s stock selection in health care hurt relative benchmark returns. Security selection decisions in information technology and consumer staples added the most to relative benchmark returns. | |
| Performance Past Does Not Indicate Future [Text] | The performance data quoted represents past performance, which is no guarantee of future results. | |
| Line Graph [Table Text Block] | Fund The line graph below shows the change in value of a $10,000 investment made in Class A shares of the Fund at public offering price during the periods shown, compared to that of the S&P 500 Total Return Index. GROWTH OF $10,000 | |
| Average Annual Return [Table Text Block] | AVERAGE ANNUAL TOTAL RETURN 1 Year 5 Years 10 Years Class A (with sales charge) 15.53 % 13.66 % 12.46 % Class A (without sales charge) 22.58 % 15.01 % 13.13 % S&P 500 Total Return Index 25.02 % 14.53 % 13.10 % | |
| No Deduction of Taxes [Text Block] | The graph and table do not reflect the deduction of taxes that a shareholder would pay on fund distributions or redemption of fund shares. | |
| Updated Performance Information Location [Text Block] | Call 1-800-225-6292 or visit https://www.amundi.com/usinvestors/Resources/Shareholder-Reports | |
| Net Assets | $ 8,969,098,320 | |
| Holdings Count | Holding | 44 | [1] |
| Advisory Fees Paid, Amount | $ 49,705,321 | |
| Investment Company Portfolio Turnover | 64% | |
| Additional Fund Statistics [Text Block] | KEY FUND STATISTICS Fund net assets $ % Total number of portfolio holdings 44 ^^ Total advisory fee paid $ Portfolio turnover rate 64 % ^^ Excluding short-term investments and all derivative contracts except for options purchased. | |
| Holdings [Text Block] | SECTOR DISTRIBUTION (as of December 31, 2024 ) * Information Technology 32.0 % Financials 18.0 % Health Care 11.2 % Industrials 10.5 % Basic Materials 9.3 % Consumer Discretionary 9.0 % Communication Services 5.4 % Consumer Staples 2.5 % Energy 2.1 % * As a percentage of total investments excluding short-term investments and all derivative contracts except for options purchased. | |
| Material Fund Change [Text Block] | Material Fund Changes Amundi Asset Management US, Inc. (the “Adviser”), the Fund’s investment adviser, is currently an indirect, wholly-owned subsidiary of Amundi. On July 9, 2024, Amundi announced that it had entered into a definitive agreement with Victory Capital Holdings, Inc. (“Victory Capital”) to combine the Adviser with Victory Capital, and for Amundi to become a strategic shareholder of Victory Capital (the “Transaction”). Victory Capital is headquartered in San Antonio, Texas. The closing of the Transaction is subject to certain regulatory approvals and other conditions. There is no assurance that the Transaction will close. Under the terms of the Transaction, subject to Fund shareholder approval, the Fund is expected to be reorganized into a corresponding, newly established Victory Fund advised by Victory Capital Management Inc., an affiliate of Victory Capital (the “Reorganization”). The Fund’s Board of Trustees has approved the Reorganization. The Reorganization is contingent upon the completion of certain conditions, including approval by the shareholders of the Fund. There is no assurance that the shareholders of the Fund will approve the proposal to reorganize the Fund. For more complete information, you may review the Fund's next prospectus, which we expect to be available by May 1, 2025 at https://www.amundi.com/usinvestors/Products/Mutual-Funds | |
| Summary of Change Legend [Text Block] | For more complete information, you may review the Fund's next prospectus, which we expect to be available by May 1, 2025 at https://www.amundi.com/usinvestors/Products/Mutual-Funds | |
| Updated Prospectus Phone Number | 1-800-225-6292 | |
| Updated Prospectus Web Address | https://www.amundi.com/usinvestors/Products/Mutual-Funds | |
| C000011120 [Member] | ||
| Shareholder Report [Line Items] | ||
| Fund Name | Pioneer Fund | |
| Class Name | Class C | |
| Trading Symbol | PCODX | |
| Annual or Semi-Annual Statement [Text Block] | This annual shareholder report contains important information about Pioneer Fund (“Fund”) for the period of January 1, 2024 to December 31, 2024. | |
| Shareholder Report Annual or Semi-Annual | annual shareholder report | |
| Additional Information [Text Block] | You can find additional information about the Fund at https://www.amundi.com/usinvestors/Resources/Shareholder-Reports | |
| Material Fund Change Notice [Text Block] | This report describes changes to the Fund that occurred during the reporting period. | |
| Additional Information Phone Number | 1-800-225-6292 | |
| Additional Information Website | https://www.amundi.com/usinvestors/Resources/Shareholder-Reports | |
| Expenses [Text Block] | What were the Fund costs for the last year? (Based on a hypothetical $10,000 investment) Class Name Costs of a $10,000 investment Costs paid as a percentage of a $10,000 investment Class C $ 1.72 % | |
| Expenses Paid, Amount | $ 191 | |
| Expense Ratio, Percent | 1.72% | |
| Factors Affecting Performance [Text Block] | How did the Fund perform last year and what affected the Fund performance? For the fiscal year ended December 31, 2024, the Fund’s Sector allocation decisions accounted for the Fund’s benchmark relative underperformance; specifically, an overweight to materials, accounted for the majority of the underperformance. In addition, the Portfolio’s stock selection in health care hurt relative benchmark returns. Security selection decisions in information technology and consumer staples added the most to relative benchmark returns. | |
| Performance Past Does Not Indicate Future [Text] | The performance data quoted represents past performance, which is no guarantee of future results. | |
| Line Graph [Table Text Block] | Fund The line graph below shows the change in value of a $10,000 investment made in Class C shares of the Fund during the periods shown, compared to that of the S&P 500 Total Return Index. GROWTH OF $10,000 | |
| Average Annual Return [Table Text Block] | AVERAGE ANNUAL TOTAL RETURN 1 Year 5 Years 10 Years Class C (with contingent deferred sales charge) 20.64 % 14.11 % 12.24 % Class C (without contingent deferred sales charge) 21.64 % 14.11 % 12.24 % S&P 500 Total Return Index 25.02 % 14.53 % 13.10 % | |
| No Deduction of Taxes [Text Block] | The graph and table do not reflect the deduction of taxes that a shareholder would pay on fund distributions or redemption of fund shares. | |
| Updated Performance Information Location [Text Block] | Call 1-800-225-6292 or visit https://www.amundi.com/usinvestors/Resources/Shareholder-Reports | |
| Net Assets | $ 8,969,098,320 | |
| Holdings Count | Holding | 44 | [2] |
| Advisory Fees Paid, Amount | $ 49,705,321 | |
| Investment Company Portfolio Turnover | 64% | |
| Additional Fund Statistics [Text Block] | KEY FUND STATISTICS Fund net assets $ % Total number of portfolio holdings 44 ^^ Total advisory fee paid $ Portfolio turnover rate 64 % ^^ Excluding short-term investments and all derivative contracts except for options purchased. | |
| Holdings [Text Block] | SECTOR DISTRIBUTION (as of December 31, 2024 ) * Information Technology 32.0 % Financials 18.0 % Health Care 11.2 % Industrials 10.5 % Basic Materials 9.3 % Consumer Discretionary 9.0 % Communication Services 5.4 % Consumer Staples 2.5 % Energy 2.1 % * As a percentage of total investments excluding short-term investments and all derivative contracts except for options purchased. | |
| Material Fund Change [Text Block] | Material Fund Changes Amundi Asset Management US, Inc. (the “Adviser”), the Fund’s investment adviser, is currently an indirect, wholly-owned subsidiary of Amundi. On July 9, 2024, Amundi announced that it had entered into a definitive agreement with Victory Capital Holdings, Inc. (“Victory Capital”) to combine the Adviser with Victory Capital, and for Amundi to become a strategic shareholder of Victory Capital (the “Transaction”). Victory Capital is headquartered in San Antonio, Texas. The closing of the Transaction is subject to certain regulatory approvals and other conditions. There is no assurance that the Transaction will close. Under the terms of the Transaction, subject to Fund shareholder approval, the Fund is expected to be reorganized into a corresponding, newly established Victory Fund advised by Victory Capital Management Inc., an affiliate of Victory Capital (the “Reorganization”). The Fund’s Board of Trustees has approved the Reorganization. The Reorganization is contingent upon the completion of certain conditions, including approval by the shareholders of the Fund. There is no assurance that the shareholders of the Fund will approve the proposal to reorganize the Fund. For more complete information, you may review the Fund's next prospectus, which we expect to be available by May 1, 2025 at https://www.amundi.com/usinvestors/Products/Mutual-Funds | |
| Summary of Change Legend [Text Block] | For more complete information, you may review the Fund's next prospectus, which we expect to be available by May 1, 2025 at https://www.amundi.com/usinvestors/Products/Mutual-Funds | |
| Updated Prospectus Phone Number | 1-800-225-6292 | |
| Updated Prospectus Web Address | https://www.amundi.com/usinvestors/Products/Mutual-Funds | |
| C000202421 [Member] | ||
| Shareholder Report [Line Items] | ||
| Fund Name | Pioneer Fund | |
| Class Name | Class K | |
| Trading Symbol | PIOKX | |
| Annual or Semi-Annual Statement [Text Block] | This annual shareholder report contains important information about Pioneer Fund (“Fund”) for the period of January 1, 2024 to December 31, 2024. | |
| Shareholder Report Annual or Semi-Annual | annual shareholder report | |
| Additional Information [Text Block] | You can find additional information about the Fund at https://www.amundi.com/usinvestors/Resources/Shareholder-Reports | |
| Material Fund Change Notice [Text Block] | This report describes changes to the Fund that occurred during the reporting period. | |
| Additional Information Phone Number | 1-800-225-6292 | |
| Additional Information Website | https://www.amundi.com/usinvestors/Resources/Shareholder-Reports | |
| Expenses [Text Block] | What were the Fund costs for the last year? (Based on a hypothetical $10,000 investment) Class Name Costs of a $10,000 investment Costs paid as a percentage of a $10,000 investment Class K $ 0.64 % | |
| Expenses Paid, Amount | $ 71 | |
| Expense Ratio, Percent | 0.64% | |
| Factors Affecting Performance [Text Block] | How did the Fund perform last year and what affected the Fund performance? For the fiscal year ended December 31, 2024, the Fund’s Sector allocation decisions accounted for the Fund’s benchmark relative underperformance; specifically, an overweight to materials, accounted for the majority of the underperformance. In addition, the Portfolio’s stock selection in health care hurt relative benchmark returns. Security selection decisions in information technology and consumer staples added the most to relative benchmark returns. | |
| Performance Past Does Not Indicate Future [Text] | The performance data quoted represents past performance, which is no guarantee of future results. | |
| Line Graph [Table Text Block] | Fund The line graph below shows the change in value of a $5 million investment made in Class K shares of the Fund during the periods shown, compared to that of the S&P 500 Total Return Index. GROWTH OF $5 million | |
| Average Annual Return [Table Text Block] | AVERAGE ANNUAL TOTAL RETURN 1 Year 5 Years 10 Years Class K 22.94 % 15.36 % 13.31 % S&P 500 Total Return Index 25.02 % 14.53 % 13.10 % | |
| Performance Inception Date | Dec. 30, 2019 | |
| No Deduction of Taxes [Text Block] | The graph and table do not reflect the deduction of taxes that a shareholder would pay on fund distributions or redemption of fund shares. | |
| Updated Performance Information Location [Text Block] | Call 1-800-225-6292 or visit https://www.amundi.com/usinvestors/Resources/Shareholder-Reports | |
| Net Assets | $ 8,969,098,320 | |
| Holdings Count | Holding | 44 | [3] |
| Advisory Fees Paid, Amount | $ 49,705,321 | |
| Investment Company Portfolio Turnover | 64% | |
| Additional Fund Statistics [Text Block] | KEY FUND STATISTICS Fund net assets $ % Total number of portfolio holdings 44 ^^ Total advisory fee paid $ Portfolio turnover rate 64 % ^^ Excluding short-term investments and all derivative contracts except for options purchased. | |
| Holdings [Text Block] | SECTOR DISTRIBUTION (as of December 31, 2024 ) * Information Technology 32.0 % Financials 18.0 % Health Care 11.2 % Industrials 10.5 % Basic Materials 9.3 % Consumer Discretionary 9.0 % Communication Services 5.4 % Consumer Staples 2.5 % Energy 2.1 % * As a percentage of total investments excluding short-term investments and all derivative contracts except for options purchased. | |
| Material Fund Change [Text Block] | Material Fund Changes Amundi Asset Management US, Inc. (the “Adviser”), the Fund’s investment adviser, is currently an indirect, wholly-owned subsidiary of Amundi. On July 9, 2024, Amundi announced that it had entered into a definitive agreement with Victory Capital Holdings, Inc. (“Victory Capital”) to combine the Adviser with Victory Capital, and for Amundi to become a strategic shareholder of Victory Capital (the “Transaction”). Victory Capital is headquartered in San Antonio, Texas. The closing of the Transaction is subject to certain regulatory approvals and other conditions. There is no assurance that the Transaction will close. Under the terms of the Transaction, subject to Fund shareholder approval, the Fund is expected to be reorganized into a corresponding, newly established Victory Fund advised by Victory Capital Management Inc., an affiliate of Victory Capital (the “Reorganization”). The Fund’s Board of Trustees has approved the Reorganization. The Reorganization is contingent upon the completion of certain conditions, including approval by the shareholders of the Fund. There is no assurance that the shareholders of the Fund will approve the proposal to reorganize the Fund. For more complete information, you may review the Fund's next prospectus, which we expect to be available by May 1, 2025 at https://www.amundi.com/usinvestors/Products/Mutual-Funds | |
| Summary of Change Legend [Text Block] | For more complete information, you may review the Fund's next prospectus, which we expect to be available by May 1, 2025 at https://www.amundi.com/usinvestors/Products/Mutual-Funds | |
| Updated Prospectus Phone Number | 1-800-225-6292 | |
| Updated Prospectus Web Address | https://www.amundi.com/usinvestors/Products/Mutual-Funds | |
| C000011122 [Member] | ||
| Shareholder Report [Line Items] | ||
| Fund Name | Pioneer Fund | |
| Class Name | Class R | |
| Trading Symbol | PIORX | |
| Annual or Semi-Annual Statement [Text Block] | This annual shareholder report contains important information about Pioneer Fund (“Fund”) for the period of January 1, 2024 to December 31, 2024. | |
| Shareholder Report Annual or Semi-Annual | annual shareholder report | |
| Additional Information [Text Block] | You can find additional information about the Fund at https://www.amundi.com/usinvestors/Resources/Shareholder-Reports | |
| Material Fund Change Notice [Text Block] | This report describes changes to the Fund that occurred during the reporting period. | |
| Additional Information Phone Number | 1-800-225-6292 | |
| Additional Information Website | https://www.amundi.com/usinvestors/Resources/Shareholder-Reports | |
| Expenses [Text Block] | What were the Fund costs for the last year? (Based on a hypothetical $10,000 investment) Class Name Costs of a $10,000 investment Costs paid as a percentage of a $10,000 investment Class R $ 1.37 % | |
| Expenses Paid, Amount | $ 152 | |
| Expense Ratio, Percent | 1.37% | |
| Factors Affecting Performance [Text Block] | How did the Fund perform last year and what affected the Fund performance? For the fiscal year ended December 31, 2024, the Fund’s Sector allocation decisions accounted for the Fund’s benchmark relative underperformance; specifically, an overweight to materials, accounted for the majority of the underperformance. In addition, the Portfolio’s stock selection in health care hurt relative benchmark returns. Security selection decisions in information technology and consumer staples added the most to relative benchmark returns. | |
| Performance Past Does Not Indicate Future [Text] | The performance data quoted represents past performance, which is no guarantee of future results. | |
| Line Graph [Table Text Block] | Fund The line graph below shows the change in value of a $10,000 investment made in Class R shares of the Fund during the periods shown, compared to that of the S&P 500 Total Return Index. GROWTH OF $10,000 | |
| Average Annual Return [Table Text Block] | AVERAGE ANNUAL TOTAL RETURN 1 Year 5 Years 10 Years Class R 22.03 % 14.51 % 12.66 % S&P 500 Total Return Index 25.02 % 14.53 % 13.10 % | |
| No Deduction of Taxes [Text Block] | The graph and table do not reflect the deduction of taxes that a shareholder would pay on fund distributions or redemption of fund shares. | |
| Updated Performance Information Location [Text Block] | Call 1-800-225-6292 or visit https://www.amundi.com/usinvestors/Resources/Shareholder-Reports | |
| Net Assets | $ 8,969,098,320 | |
| Holdings Count | Holding | 44 | [4] |
| Advisory Fees Paid, Amount | $ 49,705,321 | |
| Investment Company Portfolio Turnover | 64% | |
| Additional Fund Statistics [Text Block] | KEY FUND STATISTICS Fund net assets $ % Total number of portfolio holdings 44 ^^ Total advisory fee paid $ Portfolio turnover rate 64 % ^^ Excluding short-term investments and all derivative contracts except for options purchased. | |
| Holdings [Text Block] | SECTOR DISTRIBUTION (as of December 31, 2024 ) * Information Technology 32.0 % Financials 18.0 % Health Care 11.2 % Industrials 10.5 % Basic Materials 9.3 % Consumer Discretionary 9.0 % Communication Services 5.4 % Consumer Staples 2.5 % Energy 2.1 % * As a percentage of total investments excluding short-term investments and all derivative contracts except for options purchased. | |
| Material Fund Change [Text Block] | Material Fund Changes Amundi Asset Management US, Inc. (the “Adviser”), the Fund’s investment adviser, is currently an indirect, wholly-owned subsidiary of Amundi. On July 9, 2024, Amundi announced that it had entered into a definitive agreement with Victory Capital Holdings, Inc. (“Victory Capital”) to combine the Adviser with Victory Capital, and for Amundi to become a strategic shareholder of Victory Capital (the “Transaction”). Victory Capital is headquartered in San Antonio, Texas. The closing of the Transaction is subject to certain regulatory approvals and other conditions. There is no assurance that the Transaction will close. Under the terms of the Transaction, subject to Fund shareholder approval, the Fund is expected to be reorganized into a corresponding, newly established Victory Fund advised by Victory Capital Management Inc., an affiliate of Victory Capital (the “Reorganization”). The Fund’s Board of Trustees has approved the Reorganization. The Reorganization is contingent upon the completion of certain conditions, including approval by the shareholders of the Fund. There is no assurance that the shareholders of the Fund will approve the proposal to reorganize the Fund. For more complete information, you may review the Fund's next prospectus, which we expect to be available by May 1, 2025 at https://www.amundi.com/usinvestors/Products/Mutual-Funds | |
| Summary of Change Legend [Text Block] | For more complete information, you may review the Fund's next prospectus, which we expect to be available by May 1, 2025 at https://www.amundi.com/usinvestors/Products/Mutual-Funds | |
| Updated Prospectus Phone Number | 1-800-225-6292 | |
| Updated Prospectus Web Address | https://www.amundi.com/usinvestors/Products/Mutual-Funds | |
| C000011121 [Member] | ||
| Shareholder Report [Line Items] | ||
| Fund Name | Pioneer Fund | |
| Class Name | Class Y | |
| Trading Symbol | PYODX | |
| Annual or Semi-Annual Statement [Text Block] | This annual shareholder report contains important information about Pioneer Fund (“Fund”) for the period of January 1, 2024 to December 31, 2024. | |
| Shareholder Report Annual or Semi-Annual | annual shareholder report | |
| Additional Information [Text Block] | You can find additional information about the Fund at https://www.amundi.com/usinvestors/Resources/Shareholder-Reports | |
| Material Fund Change Notice [Text Block] | This report describes changes to the Fund that occurred during the reporting period. | |
| Additional Information Phone Number | 1-800-225-6292 | |
| Additional Information Website | https://www.amundi.com/usinvestors/Resources/Shareholder-Reports | |
| Expenses [Text Block] | What were the Fund costs for the last year? (Based on a hypothetical $10,000 investment) Class Name Costs of a $10,000 investment Costs paid as a percentage of a $10,000 investment Class Y $ 0.64 % | |
| Expenses Paid, Amount | $ 71 | |
| Expense Ratio, Percent | 0.64% | |
| Factors Affecting Performance [Text Block] | How did the Fund perform last year and what affected the Fund performance? For the fiscal year ended December 31, 2024, the Fund’s Sector allocation decisions accounted for the Fund’s benchmark relative underperformance; specifically, an overweight to materials, accounted for the majority of the underperformance. In addition, the Portfolio’s stock selection in health care hurt relative benchmark returns. Security selection decisions in information technology and consumer staples added the most to relative benchmark returns. | |
| Performance Past Does Not Indicate Future [Text] | The performance data quoted represents past performance, which is no guarantee of future results. | |
| Line Graph [Table Text Block] | Fund The line graph below shows the change in value of a $5 million investment made in Class Y shares of the Fund during the periods shown, compared to that of the S&P 500 Total Return Index. GROWTH OF $5 million | |
| Average Annual Return [Table Text Block] | AVERAGE ANNUAL TOTAL RETURN 1 Year 5 Years 10 Years Class Y 22.92 % 15.36 % 13.44 % S&P 500 Total Return Index 25.02 % 14.53 % 13.10 % | |
| No Deduction of Taxes [Text Block] | The graph and table do not reflect the deduction of taxes that a shareholder would pay on fund distributions or redemption of fund shares. | |
| Updated Performance Information Location [Text Block] | Call 1-800-225-6292 or visit https://www.amundi.com/usinvestors/Resources/Shareholder-Reports | |
| Net Assets | $ 8,969,098,320 | |
| Holdings Count | Holding | 44 | [5] |
| Advisory Fees Paid, Amount | $ 49,705,321 | |
| Investment Company Portfolio Turnover | 64% | |
| Additional Fund Statistics [Text Block] | KEY FUND STATISTICS Fund net assets $ % Total number of portfolio holdings 44 ^^ Total advisory fee paid $ Portfolio turnover rate 64 % ^^ Excluding short-term investments and all derivative contracts except for options purchased. | |
| Holdings [Text Block] | SECTOR DISTRIBUTION (as of December 31, 2024 ) * Information Technology 32.0 % Financials 18.0 % Health Care 11.2 % Industrials 10.5 % Basic Materials 9.3 % Consumer Discretionary 9.0 % Communication Services 5.4 % Consumer Staples 2.5 % Energy 2.1 % * As a percentage of total investments excluding short-term investments and all derivative contracts except for options purchased. | |
| Material Fund Change [Text Block] | Material Fund Changes Amundi Asset Management US, Inc. (the “Adviser”), the Fund’s investment adviser, is currently an indirect, wholly-owned subsidiary of Amundi. On July 9, 2024, Amundi announced that it had entered into a definitive agreement with Victory Capital Holdings, Inc. (“Victory Capital”) to combine the Adviser with Victory Capital, and for Amundi to become a strategic shareholder of Victory Capital (the “Transaction”). Victory Capital is headquartered in San Antonio, Texas. The closing of the Transaction is subject to certain regulatory approvals and other conditions. There is no assurance that the Transaction will close. Under the terms of the Transaction, subject to Fund shareholder approval, the Fund is expected to be reorganized into a corresponding, newly established Victory Fund advised by Victory Capital Management Inc., an affiliate of Victory Capital (the “Reorganization”). The Fund’s Board of Trustees has approved the Reorganization. The Reorganization is contingent upon the completion of certain conditions, including approval by the shareholders of the Fund. There is no assurance that the shareholders of the Fund will approve the proposal to reorganize the Fund. For more complete information, you may review the Fund's next prospectus, which we expect to be available by May 1, 2025 at https://www.amundi.com/usinvestors/Products/Mutual-Funds | |
| Summary of Change Legend [Text Block] | For more complete information, you may review the Fund's next prospectus, which we expect to be available by May 1, 2025 at https://www.amundi.com/usinvestors/Products/Mutual-Funds | |
| Updated Prospectus Phone Number | 1-800-225-6292 | |
| Updated Prospectus Web Address | https://www.amundi.com/usinvestors/Products/Mutual-Funds | |
| [1]Excluding short-term investments and all derivative contracts except for options purchased.[2]Excluding short-term investments and all derivative contracts except for options purchased.[3]Excluding short-term investments and all derivative contracts except for options purchased.[4]Excluding short-term investments and all derivative contracts except for options purchased.[5]Excluding short-term investments and all derivative contracts except for options purchased. | ||
| Shareholder Report, Line Graph (Details) - USD ($) | 12 Months Ended | 60 Months Ended | 120 Months Ended | ||||||||||
| Dec. 31, 2024 | Dec. 31, 2024 | 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 | Dec. 31, 2015 | Dec. 31, 2014 | |
| C000011118 [Member] | |||||||||||||
| Account Value [Line Items] | |||||||||||||
| Line Graph and Table Measure Name | Class A (with sales charge) | ||||||||||||
| Account Value | $ 32,371.32 | $ 32,371.32 | $ 32,371.32 | $ 26,407.51 | $ 20,516.98 | $ 25,478.03 | $ 19,934.83 | $ 16,089.18 | $ 12,281.65 | $ 12,499.54 | $ 10,284.59 | $ 9,384 | $ 9,425 |
| Average Annual Return, Percent | 15.53% | 13.66% | 12.46% | ||||||||||
| C000011118 [Member] | Without Sales Load [Member] | |||||||||||||
| Account Value [Line Items] | |||||||||||||
| Line Graph and Table Measure Name | Class A (without sales charge) | ||||||||||||
| Average Annual Return, Percent | 22.58% | 15.01% | 13.13% | ||||||||||
| C000011120 [Member] | |||||||||||||
| Account Value [Line Items] | |||||||||||||
| Line Graph and Table Measure Name | Class C (with contingent deferred sales charge) | ||||||||||||
| Account Value | $ 31,732.50 | $ 31,732.50 | $ 31,732.50 | 26,086.23 | 20,432.66 | 25,574.31 | 20,170.36 | 16,400.53 | 12,623.59 | 12,949.81 | 10,740.16 | 9,877.25 | 9,999.99 |
| Average Annual Return, Percent | 20.64% | 14.11% | 12.24% | ||||||||||
| C000011120 [Member] | Without Sales Load [Member] | |||||||||||||
| Account Value [Line Items] | |||||||||||||
| Line Graph and Table Measure Name | Class C (without contingent deferred sales charge) | ||||||||||||
| Average Annual Return, Percent | 21.64% | 14.11% | 12.24% | ||||||||||
| C000202421 [Member] | |||||||||||||
| Account Value [Line Items] | |||||||||||||
| Line Graph and Table Measure Name | Class K | ||||||||||||
| Account Value | $ 17,442,464.59 | $ 17,442,464.59 | $ 17,442,464.59 | 14,188,385.51 | 10,993,466.83 | 13,609,283.53 | 10,613,221.86 | 8,536,286.62 | 6,515,895.48 | 6,631,501.33 | 5,456,385.89 | 4,978,591.06 | 5,000,000.01 |
| Average Annual Return, Percent | 22.94% | 15.36% | 13.31% | ||||||||||
| C000011122 [Member] | |||||||||||||
| Account Value [Line Items] | |||||||||||||
| Line Graph and Table Measure Name | Class R | ||||||||||||
| Account Value | $ 32,932.07 | $ 32,932.07 | $ 32,932.07 | 26,985.93 | 21,057.17 | 26,275.12 | 20,643.76 | 16,728.1 | 12,823.45 | 13,100.81 | 10,828.36 | 9,923.4 | 10,000 |
| Average Annual Return, Percent | 22.03% | 14.51% | 12.66% | ||||||||||
| C000011121 [Member] | |||||||||||||
| Account Value [Line Items] | |||||||||||||
| Line Graph and Table Measure Name | Class Y | ||||||||||||
| Account Value | $ 17,650,361.02 | $ 17,650,361.02 | $ 17,650,361.02 | 14,360,644.28 | 11,123,085.98 | 13,774,198.37 | 10,741,352.84 | 8,639,544.91 | 6,579,356.88 | 6,683,608.75 | 5,485,038.02 | 4,992,873.74 | 5,000,000 |
| Average Annual Return, Percent | 22.92% | 15.36% | 13.44% | ||||||||||
| S And P 500 Total Return Index [Member] | |||||||||||||
| Account Value [Line Items] | |||||||||||||
| Line Graph and Table Measure Name | S&P 500 Total Return Index | ||||||||||||
| Account Value | $ 34,253.94547 | $ 34,253.94547 | $ 34,253.94547 | $ 27,398.83422 | $ 21,695.57807 | $ 26,493.8421 | $ 20,584.86909 | $ 17,386.04932 | $ 13,222.69692 | $ 13,829.01008 | $ 11,350.92519 | $ 10,138.38248 | $ 10,000 |
| Average Annual Return, Percent | 25.02% | 14.53% | 13.10% |
| Shareholder Report, Holdings (Details) | Dec. 31, 2024 | |
| C000011118 [Member] | Information Technology Sector [Member] | ||
| Holdings [Line Items] | ||
| Percent of Total Investments | 32% | [1] |
| C000011118 [Member] | Financial Services Sector [Member] | ||
| Holdings [Line Items] | ||
| Percent of Total Investments | 18% | [1] |
| C000011118 [Member] | Healthcare Sector [Member] | ||
| Holdings [Line Items] | ||
| Percent of Total Investments | 11.20% | [1] |
| C000011118 [Member] | Industrial Sector [Member] | ||
| Holdings [Line Items] | ||
| Percent of Total Investments | 10.50% | [1] |
| C000011118 [Member] | Basic Materials [Member] | ||
| Holdings [Line Items] | ||
| Percent of Total Investments | 9.30% | [1] |
| C000011118 [Member] | Consumer Discretionary Sector [Member] | ||
| Holdings [Line Items] | ||
| Percent of Total Investments | 9% | [1] |
| C000011118 [Member] | Communications Sector [Member] | ||
| Holdings [Line Items] | ||
| Percent of Total Investments | 5.40% | [1] |
| C000011118 [Member] | Consumer Staples Sector [Member] | ||
| Holdings [Line Items] | ||
| Percent of Total Investments | 2.50% | [1] |
| C000011118 [Member] | Energy Sector [Member] | ||
| Holdings [Line Items] | ||
| Percent of Total Investments | 2.10% | [1] |
| C000011120 [Member] | Information Technology Sector [Member] | ||
| Holdings [Line Items] | ||
| Percent of Total Investments | 32% | [2] |
| C000011120 [Member] | Financial Services Sector [Member] | ||
| Holdings [Line Items] | ||
| Percent of Total Investments | 18% | [2] |
| C000011120 [Member] | Healthcare Sector [Member] | ||
| Holdings [Line Items] | ||
| Percent of Total Investments | 11.20% | [2] |
| C000011120 [Member] | Industrial Sector [Member] | ||
| Holdings [Line Items] | ||
| Percent of Total Investments | 10.50% | [2] |
| C000011120 [Member] | Basic Materials [Member] | ||
| Holdings [Line Items] | ||
| Percent of Total Investments | 9.30% | [2] |
| C000011120 [Member] | Consumer Discretionary Sector [Member] | ||
| Holdings [Line Items] | ||
| Percent of Total Investments | 9% | [2] |
| C000011120 [Member] | Communications Sector [Member] | ||
| Holdings [Line Items] | ||
| Percent of Total Investments | 5.40% | [2] |
| C000011120 [Member] | Consumer Staples Sector [Member] | ||
| Holdings [Line Items] | ||
| Percent of Total Investments | 2.50% | [2] |
| C000011120 [Member] | Energy Sector [Member] | ||
| Holdings [Line Items] | ||
| Percent of Total Investments | 2.10% | [2] |
| C000202421 [Member] | Information Technology Sector [Member] | ||
| Holdings [Line Items] | ||
| Percent of Total Investments | 32% | [3] |
| C000202421 [Member] | Financial Services Sector [Member] | ||
| Holdings [Line Items] | ||
| Percent of Total Investments | 18% | [3] |
| C000202421 [Member] | Healthcare Sector [Member] | ||
| Holdings [Line Items] | ||
| Percent of Total Investments | 11.20% | [3] |
| C000202421 [Member] | Industrial Sector [Member] | ||
| Holdings [Line Items] | ||
| Percent of Total Investments | 10.50% | [3] |
| C000202421 [Member] | Basic Materials [Member] | ||
| Holdings [Line Items] | ||
| Percent of Total Investments | 9.30% | [3] |
| C000202421 [Member] | Consumer Discretionary Sector [Member] | ||
| Holdings [Line Items] | ||
| Percent of Total Investments | 9% | [3] |
| C000202421 [Member] | Communications Sector [Member] | ||
| Holdings [Line Items] | ||
| Percent of Total Investments | 5.40% | [3] |
| C000202421 [Member] | Consumer Staples Sector [Member] | ||
| Holdings [Line Items] | ||
| Percent of Total Investments | 2.50% | [3] |
| C000202421 [Member] | Energy Sector [Member] | ||
| Holdings [Line Items] | ||
| Percent of Total Investments | 2.10% | [3] |
| C000011122 [Member] | Information Technology Sector [Member] | ||
| Holdings [Line Items] | ||
| Percent of Total Investments | 32% | [4] |
| C000011122 [Member] | Financial Services Sector [Member] | ||
| Holdings [Line Items] | ||
| Percent of Total Investments | 18% | [4] |
| C000011122 [Member] | Healthcare Sector [Member] | ||
| Holdings [Line Items] | ||
| Percent of Total Investments | 11.20% | [4] |
| C000011122 [Member] | Industrial Sector [Member] | ||
| Holdings [Line Items] | ||
| Percent of Total Investments | 10.50% | [4] |
| C000011122 [Member] | Basic Materials [Member] | ||
| Holdings [Line Items] | ||
| Percent of Total Investments | 9.30% | [4] |
| C000011122 [Member] | Consumer Discretionary Sector [Member] | ||
| Holdings [Line Items] | ||
| Percent of Total Investments | 9% | [4] |
| C000011122 [Member] | Communications Sector [Member] | ||
| Holdings [Line Items] | ||
| Percent of Total Investments | 5.40% | [4] |
| C000011122 [Member] | Consumer Staples Sector [Member] | ||
| Holdings [Line Items] | ||
| Percent of Total Investments | 2.50% | [4] |
| C000011122 [Member] | Energy Sector [Member] | ||
| Holdings [Line Items] | ||
| Percent of Total Investments | 2.10% | [4] |
| C000011121 [Member] | Information Technology Sector [Member] | ||
| Holdings [Line Items] | ||
| Percent of Total Investments | 32% | [5] |
| C000011121 [Member] | Financial Services Sector [Member] | ||
| Holdings [Line Items] | ||
| Percent of Total Investments | 18% | [5] |
| C000011121 [Member] | Healthcare Sector [Member] | ||
| Holdings [Line Items] | ||
| Percent of Total Investments | 11.20% | [5] |
| C000011121 [Member] | Industrial Sector [Member] | ||
| Holdings [Line Items] | ||
| Percent of Total Investments | 10.50% | [5] |
| C000011121 [Member] | Basic Materials [Member] | ||
| Holdings [Line Items] | ||
| Percent of Total Investments | 9.30% | [5] |
| C000011121 [Member] | Consumer Discretionary Sector [Member] | ||
| Holdings [Line Items] | ||
| Percent of Total Investments | 9% | [5] |
| C000011121 [Member] | Communications Sector [Member] | ||
| Holdings [Line Items] | ||
| Percent of Total Investments | 5.40% | [5] |
| C000011121 [Member] | Consumer Staples Sector [Member] | ||
| Holdings [Line Items] | ||
| Percent of Total Investments | 2.50% | [5] |
| C000011121 [Member] | Energy Sector [Member] | ||
| Holdings [Line Items] | ||
| Percent of Total Investments | 2.10% | [5] |
| [1]As a percentage of total investments excluding short-term investments and all derivative contracts except for options purchased.[2]As a percentage of total investments excluding short-term investments and all derivative contracts except for options purchased.[3]As a percentage of total investments excluding short-term investments and all derivative contracts except for options purchased.[4]As a percentage of total investments excluding short-term investments and all derivative contracts except for options purchased.[5]As a percentage of total investments excluding short-term investments and all derivative contracts except for options purchased. | ||
