| Form N-CSR Cover | 12 Months Ended |
| Dec. 31, 2024 | |
| Shareholder Report [Line Items] | |
| Document Type | N-CSR |
| Amendment Flag | false |
| Registrant Name | Fidelity Contrafund |
| Entity Central Index Key | 0000024238 |
| Entity Investment Company Type | N-1A |
| Document Period End Date | Dec. 31, 2024 |
| Shareholder Report | 12 Months Ended |
| Dec. 31, 2024 USD ($) shares | |
| Shareholder Report [Line Items] | |
| Document Type | N-CSR |
| Amendment Flag | false |
| Registrant Name | Fidelity Contrafund |
| Entity Central Index Key | 0000024238 |
| Entity Investment Company Type | N-1A |
| Document Period End Date | Dec. 31, 2024 |
| Fidelity Advisor New Insights Fund - Class C | |
| Shareholder Report [Line Items] | |
| Fund Name | Fidelity Advisor® New Insights Fund |
| Class Name | Fidelity Advisor® New Insights Fund Class C |
| Trading Symbol | FNICX |
| Annual or Semi-Annual Statement [Text Block] | This annual shareholder report contains information about Fidelity Advisor® New Insights Fund for the period 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 fundresearch.fidelity.com/prospectus/sec. You can also request this information by contacting us at 1-877-208-0098 or by sending an e-mail to fidfunddocuments@fidelity.com. |
| Material Fund Change Notice [Text Block] | This report describes changes to the Fund that occurred during the reporting period. |
| Additional Information Phone Number | 1-877-208-0098 |
| Additional Information Email | fidfunddocuments@fidelity.com |
| Additional Information Website | fundresearch.fidelity.com/prospectus/sec |
| Expenses [Text Block] | What were your Fund costs for the last year? (based on hypothetical $10,000 investment) FUND COST (PREVIOUS YEAR) Costs of a $10,000 investment Costs paid as a percentage of a $10,000 investment Class C $ 1.65 % |
| Expenses Paid, Amount | $ 193 |
| Expense Ratio, Percent | 1.65% |
| Factors Affecting Performance [Text Block] | What affected the Fund's performance this period? • • • • • • |
| Performance Past Does Not Indicate Future [Text] | The Fund's past performance is not a good predictor of the Fund's future performance.</span>" id="sjs-B26"><span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:italic;font-weight:normal;">The Fund's past performance is not a good predictor of the Fund's future performance.</span> |
| Line Graph [Table Text Block] | How did the Fund perform over the past 10 years? CUMULATIVE PERFORMANCE December 31, 2014 through December 31, 2024. Initial investment of $10,000. Class C $10,000 $10,163 $10,721 $13,614 $12,918 $16,554 $20,319 $25,065 $18,043 $24,529 $33,091 S&P 500® Index $10,000 $10,138 $11,351 $13,829 $13,223 $17,386 $20,585 $26,494 $21,696 $27,399 $34,254 2014 2015 2016 2017 2018 2019 2020 2021 2022 2023 2024 |
| Average Annual Return [Table Text Block] | AVERAGE ANNUAL TOTAL RETURNS: 1 Year 5 Year 10 Year Class C (incl. contingent deferred sales charge) 32.89% 14.50% 12.71% Class C 33.89% 14.50% 12.71% S&P 500® Index 25.02% 14.53% 13.10% Visit institutional.fidelity.com for more recent performance information. The Fund's past performance is not a good predictor of the Fund's future performance. The graph and table do not reflect the deduction of taxes that a shareholder would pay on fund distributions or redemption of fund shares. |
| 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. |
| Net Assets | $ 21,798,939,502 |
| Holdings Count | shares | 443 |
| Advisory Fees Paid, Amount | $ 125,752,187 |
| Investment Company Portfolio Turnover | 18% |
| Additional Fund Statistics [Text Block] | Key Fund Statistics (as of December 31, 2024) KEY FACTS Fund Size $ Number of Holdings 443 Total Advisory Fee $ Portfolio Turnover 18 % |
| Holdings [Text Block] | MARKET SECTORS (% of Fund's net assets) Information Technology 26.0 Communication Services 21.4 Financials 14.8 Industrials 12.3 Consumer Discretionary 11.4 Health Care 8.3 Materials 1.5 Energy 1.5 Utilities 1.2 Consumer Staples 1.2 Real Estate 0.0 Common Stocks 96.9 Preferred Stocks 2.7 Preferred Securities 0.0 Short-Term Investments and Net Other Assets (Liabilities) 0.4 ASSET ALLOCATION (% of Fund's net assets) Common Stocks - 96.9 Preferred Stocks - 2.7 Preferred Securities - 0.0 Short-Term Investments and Net Other Assets (Liabilities) - 0.4 United States 92.9 Canada 1.9 Taiwan 0.7 Netherlands 0.6 United Kingdom 0.5 China 0.4 Italy 0.4 Congo Democratic Republic Of 0.4 Korea (South) 0.4 Others 1.8 GEOGRAPHIC DIVERSIFICATION (% of Fund's net assets) United States - 92.9 Canada - 1.9 Taiwan - 0.7 Netherlands - 0.6 United Kingdom - 0.5 China - 0.4 Italy - 0.4 Congo Democratic Republic Of - 0.4 Korea (South) - 0.4 Others - 1.8 |
| Largest Holdings [Text Block] | TOP HOLDINGS (% of Fund's net assets) Meta Platforms Inc Class A 11.7 NVIDIA Corp 8.9 Microsoft Corp 6.5 Alphabet Inc Class A 6.1 Amazon.com Inc 5.8 Berkshire Hathaway Inc Class A 5.1 Apple Inc 2.6 Netflix Inc 2.6 Space Exploration Technologies Corp 2.3 Eli Lilly & Co 2.2 53.8 |
| Material Fund Change [Text Block] | How has the Fund changed? This is a summary of certain changes to the Fund since January 1, 2024. For more complete information, you may review the Fund's next prospectus, which we expect to be available by March 1, 2025 at fundresearch.fidelity.com/prospectus/sec or upon request at 1-877-208-0098 or by sending an e-mail to fidfunddocuments fidelity.com . The fees associated with this class changed during the reporting year. The variations in class fees are primarily the result of the following changes: Management fee Operating expenses Performance adjustment fee The fund's transfer agent and pricing & bookkeeping fees were changed to a fixed rate effective December 1, 2023. Effective March 1, 2024, the fund's management contract was amended to incorporate administrative services previously covered under separate services agreements (transfer agent and pricing & bookkeeping). The amended contract incorporates a basic fee rate that may vary by class (subject to a performance adjustment). The Adviser or an affiliate pays certain expenses of managing and operating the fund out of each class's management fee. |
| Material Fund Change Expenses [Text Block] | The fees associated with this class changed during the reporting year. The variations in class fees are primarily the result of the following changes: Management fee Operating expenses Performance adjustment fee The fund's transfer agent and pricing & bookkeeping fees were changed to a fixed rate effective December 1, 2023. Effective March 1, 2024, the fund's management contract was amended to incorporate administrative services previously covered under separate services agreements (transfer agent and pricing & bookkeeping). The amended contract incorporates a basic fee rate that may vary by class (subject to a performance adjustment). The Adviser or an affiliate pays certain expenses of managing and operating the fund out of each class's management fee. |
| Summary of Change Legend [Text Block] | This is a summary of certain changes to the Fund since January 1, 2024. For more complete information, you may review the Fund's next prospectus, which we expect to be available by March 1, 2025 at fundresearch.fidelity.com/prospectus/sec or upon request at 1-877-208-0098 or by sending an e-mail to fidfunddocuments fidelity.com . |
| Updated Prospectus Phone Number | 1-877-208-0098</span>" id="sjs-B40"><span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;">1-877-208-0098</span> |
| Updated Prospectus Email Address | fidfunddocuments@fidelity.com</span>" id="sjs-B41"><span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;">fidfunddocuments@fidelity.com</span> |
| Updated Prospectus Web Address | fundresearch.fidelity.com/prospectus/sec</span>" id="sjs-B42"><span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;">fundresearch.fidelity.com/prospectus/sec</span> |
| Fidelity Series Opportunistic Insights Fund | |
| Shareholder Report [Line Items] | |
| Fund Name | Fidelity® Series Opportunistic Insights Fund |
| Class Name | Fidelity® Series Opportunistic Insights Fund |
| Trading Symbol | FVWSX |
| Annual or Semi-Annual Statement [Text Block] | This annual shareholder report contains information about Fidelity® Series Opportunistic Insights Fund for the period 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 fundresearch.fidelity.com/prospectus/sec. You can also request this information by contacting us at 1-800-544-8544. |
| Additional Information Phone Number | 1-800-544-8544 |
| Additional Information Website | fundresearch.fidelity.com/prospectus/sec |
| Expenses [Text Block] | What were your Fund costs for the last year? (based on hypothetical $10,000 investment) FUND COST (PREVIOUS YEAR) Costs of a $10,000 investment Costs paid as a percentage of a $10,000 investment Fidelity® Series Opportunistic Insights Fund $ A 0.00 % B A Amount represents less than $.50 B Amount represents less than 0.005% |
| Expenses Paid, Amount | $ 0 |
| Expense Ratio, Percent | 0% |
| Factors Affecting Performance [Text Block] | What affected the Fund's performance this period? • • • • • • |
| Performance Past Does Not Indicate Future [Text] | The Fund's past performance is not a good predictor of the Fund's future performance.</span>" id="sjs-B57"><span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:italic;font-weight:normal;">The Fund's past performance is not a good predictor of the Fund's future performance.</span> |
| Line Graph [Table Text Block] | How did the Fund perform over the past 10 years? CUMULATIVE PERFORMANCE December 31, 2014 through December 31, 2024. Initial investment of $10,000. Fidelity® Series Opportunistic Insights Fund $10,000 $10,710 $10,853 $14,430 $14,161 $18,483 $24,246 $30,260 $22,475 $29,936 $40,819 Russell 3000® Index $10,000 $10,048 $11,327 $13,721 $13,002 $17,035 $20,593 $25,877 $20,907 $26,334 $32,604 2014 2015 2016 2017 2018 2019 2020 2021 2022 2023 2024 |
| Average Annual Return [Table Text Block] | AVERAGE ANNUAL TOTAL RETURNS: 1 Year 5 Year 10 Year Fidelity® Series Opportunistic Insights Fund 36.35% 17.17% 15.10% Russell 3000® Index 23.81% 13.86% 12.55% Visit www.fidelity.com for more recent performance information. The Fund's past performance is not a good predictor of the Fund's future performance. The graph and table do not reflect the deduction of taxes that a shareholder would pay on fund distributions or redemption of fund shares. |
| 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. |
| Net Assets | $ 11,265,136,609 |
| Holdings Count | shares | 372 |
| Advisory Fees Paid, Amount | $ 0 |
| Investment Company Portfolio Turnover | 23% |
| Additional Fund Statistics [Text Block] | Key Fund Statistics (as of December 31, 2024) KEY FACTS Fund Size $ Number of Holdings 372 Total Advisory Fee $ Portfolio Turnover 23 % |
| Holdings [Text Block] | MARKET SECTORS (% of Fund's net assets) Information Technology 24.6 Communication Services 21.4 Financials 18.0 Industrials 10.3 Consumer Discretionary 10.1 Health Care 9.0 Consumer Staples 1.4 Materials 1.1 Energy 1.1 Utilities 0.7 Real Estate 0.2 Common Stocks 96.4 Preferred Stocks 1.5 Preferred Securities 0.0 Short-Term Investments and Net Other Assets (Liabilities) 2.1 ASSET ALLOCATION (% of Fund's net assets) Common Stocks - 96.4 Preferred Stocks - 1.5 Preferred Securities - 0.0 Short-Term Investments and Net Other Assets (Liabilities) - 2.1 United States 94.1 Canada 2.1 Israel 0.6 Congo Democratic Republic Of 0.4 Taiwan 0.4 Korea (South) 0.3 Brazil 0.3 United Kingdom 0.3 Switzerland 0.2 Others 1.3 GEOGRAPHIC DIVERSIFICATION (% of Fund's net assets) United States - 94.1 Canada - 2.1 Israel - 0.6 Congo Democratic Republic Of - 0.4 Taiwan - 0.4 Korea (South) - 0.3 Brazil - 0.3 United Kingdom - 0.3 Switzerland - 0.2 Others - 1.3 |
| Largest Holdings [Text Block] | TOP HOLDINGS (% of Fund's net assets) Meta Platforms Inc Class A 13.2 NVIDIA Corp 9.8 Berkshire Hathaway Inc Class A 6.1 Amazon.com Inc 5.7 Microsoft Corp 4.5 Netflix Inc 3.0 Apple Inc 2.7 Eli Lilly & Co 2.3 Alphabet Inc Class A 2.2 Alphabet Inc Class C 2.1 51.6 |
| Fidelity Advisor New Insights Fund - Class I | |
| Shareholder Report [Line Items] | |
| Fund Name | Fidelity Advisor® New Insights Fund |
| Class Name | Fidelity Advisor® New Insights Fund Class I |
| Trading Symbol | FINSX |
| Annual or Semi-Annual Statement [Text Block] | This annual shareholder report contains information about Fidelity Advisor® New Insights Fund for the period 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 fundresearch.fidelity.com/prospectus/sec. You can also request this information by contacting us at 1-877-208-0098 or by sending an e-mail to fidfunddocuments@fidelity.com. |
| Material Fund Change Notice [Text Block] | This report describes changes to the Fund that occurred during the reporting period. |
| Additional Information Phone Number | 1-877-208-0098 |
| Additional Information Email | fidfunddocuments@fidelity.com |
| Additional Information Website | fundresearch.fidelity.com/prospectus/sec |
| Expenses [Text Block] | What were your Fund costs for the last year? (based on hypothetical $10,000 investment) FUND COST (PREVIOUS YEAR) Costs of a $10,000 investment Costs paid as a percentage of a $10,000 investment Class I $ 0.65 % |
| Expenses Paid, Amount | $ 76 |
| Expense Ratio, Percent | 0.65% |
| Factors Affecting Performance [Text Block] | What affected the Fund's performance this period? • • • • • • |
| Performance Past Does Not Indicate Future [Text] | The Fund's past performance is not a good predictor of the Fund's future performance.</span>" id="sjs-B84"><span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:italic;font-weight:normal;">The Fund's past performance is not a good predictor of the Fund's future performance.</span> |
| Line Graph [Table Text Block] | How did the Fund perform over the past 10 years? CUMULATIVE PERFORMANCE December 31, 2014 through December 31, 2024. Initial investment of $10,000. Class I $10,000 $10,264 $10,937 $14,032 $13,451 $17,409 $21,581 $26,894 $19,557 $26,648 $36,033 S&P 500® Index $10,000 $10,138 $11,351 $13,829 $13,223 $17,386 $20,585 $26,494 $21,696 $27,399 $34,254 2014 2015 2016 2017 2018 2019 2020 2021 2022 2023 2024 |
| Average Annual Return [Table Text Block] | AVERAGE ANNUAL TOTAL RETURNS: 1 Year 5 Year 10 Year Class I 35.22% 15.66% 13.68% S&P 500® Index 25.02% 14.53% 13.10% Visit institutional.fidelity.com for more recent performance information. The Fund's past performance is not a good predictor of the Fund's future performance. The graph and table do not reflect the deduction of taxes that a shareholder would pay on fund distributions or redemption of fund shares. |
| 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. |
| Net Assets | $ 21,798,939,502 |
| Holdings Count | shares | 443 |
| Advisory Fees Paid, Amount | $ 125,752,187 |
| Investment Company Portfolio Turnover | 18% |
| Additional Fund Statistics [Text Block] | Key Fund Statistics (as of December 31, 2024) KEY FACTS Fund Size $ Number of Holdings 443 Total Advisory Fee $ Portfolio Turnover 18 % |
| Holdings [Text Block] | MARKET SECTORS (% of Fund's net assets) Information Technology 26.0 Communication Services 21.4 Financials 14.8 Industrials 12.3 Consumer Discretionary 11.4 Health Care 8.3 Materials 1.5 Energy 1.5 Utilities 1.2 Consumer Staples 1.2 Real Estate 0.0 Common Stocks 96.9 Preferred Stocks 2.7 Preferred Securities 0.0 Short-Term Investments and Net Other Assets (Liabilities) 0.4 ASSET ALLOCATION (% of Fund's net assets) Common Stocks - 96.9 Preferred Stocks - 2.7 Preferred Securities - 0.0 Short-Term Investments and Net Other Assets (Liabilities) - 0.4 United States 92.9 Canada 1.9 Taiwan 0.7 Netherlands 0.6 United Kingdom 0.5 China 0.4 Italy 0.4 Congo Democratic Republic Of 0.4 Korea (South) 0.4 Others 1.8 GEOGRAPHIC DIVERSIFICATION (% of Fund's net assets) United States - 92.9 Canada - 1.9 Taiwan - 0.7 Netherlands - 0.6 United Kingdom - 0.5 China - 0.4 Italy - 0.4 Congo Democratic Republic Of - 0.4 Korea (South) - 0.4 Others - 1.8 |
| Largest Holdings [Text Block] | TOP HOLDINGS (% of Fund's net assets) Meta Platforms Inc Class A 11.7 NVIDIA Corp 8.9 Microsoft Corp 6.5 Alphabet Inc Class A 6.1 Amazon.com Inc 5.8 Berkshire Hathaway Inc Class A 5.1 Apple Inc 2.6 Netflix Inc 2.6 Space Exploration Technologies Corp 2.3 Eli Lilly & Co 2.2 53.8 |
| Material Fund Change [Text Block] | How has the Fund changed? This is a summary of certain changes to the Fund since January 1, 2024. For more complete information, you may review the Fund's next prospectus, which we expect to be available by March 1, 2025 at fundresearch.fidelity.com/prospectus/sec or upon request at 1-877-208-0098 or by sending an e-mail to fidfunddocuments fidelity.com . The fees associated with this class changed during the reporting year. The variations in class fees are primarily the result of the following changes: Management fee Operating expenses Performance adjustment fee The fund's transfer agent and pricing & bookkeeping fees were changed to a fixed rate effective December 1, 2023. Effective March 1, 2024, the fund's management contract was amended to incorporate administrative services previously covered under separate services agreements (transfer agent and pricing & bookkeeping). The amended contract incorporates a basic fee rate that may vary by class (subject to a performance adjustment). The Adviser or an affiliate pays certain expenses of managing and operating the fund out of each class's management fee. |
| Material Fund Change Expenses [Text Block] | The fees associated with this class changed during the reporting year. The variations in class fees are primarily the result of the following changes: Management fee Operating expenses Performance adjustment fee The fund's transfer agent and pricing & bookkeeping fees were changed to a fixed rate effective December 1, 2023. Effective March 1, 2024, the fund's management contract was amended to incorporate administrative services previously covered under separate services agreements (transfer agent and pricing & bookkeeping). The amended contract incorporates a basic fee rate that may vary by class (subject to a performance adjustment). The Adviser or an affiliate pays certain expenses of managing and operating the fund out of each class's management fee. |
| Summary of Change Legend [Text Block] | This is a summary of certain changes to the Fund since January 1, 2024. For more complete information, you may review the Fund's next prospectus, which we expect to be available by March 1, 2025 at fundresearch.fidelity.com/prospectus/sec or upon request at 1-877-208-0098 or by sending an e-mail to fidfunddocuments fidelity.com . |
| Updated Prospectus Phone Number | 1-877-208-0098</span>" id="sjs-B98"><span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;">1-877-208-0098</span> |
| Updated Prospectus Email Address | fidfunddocuments@fidelity.com</span>" id="sjs-B99"><span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;">fidfunddocuments@fidelity.com</span> |
| Updated Prospectus Web Address | fundresearch.fidelity.com/prospectus/sec</span>" id="sjs-B100"><span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;">fundresearch.fidelity.com/prospectus/sec</span> |
| Fidelity Advisor New Insights Fund - Class Z | |
| Shareholder Report [Line Items] | |
| Fund Name | Fidelity Advisor® New Insights Fund |
| Class Name | Fidelity Advisor® New Insights Fund Class Z |
| Trading Symbol | FZANX |
| Annual or Semi-Annual Statement [Text Block] | This annual shareholder report contains information about Fidelity Advisor® New Insights Fund for the period 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 fundresearch.fidelity.com/prospectus/sec. You can also request this information by contacting us at 1-877-208-0098 or by sending an e-mail to fidfunddocuments@fidelity.com. |
| Material Fund Change Notice [Text Block] | This report describes changes to the Fund that occurred during the reporting period. |
| Additional Information Phone Number | 1-877-208-0098 |
| Additional Information Email | fidfunddocuments@fidelity.com |
| Additional Information Website | fundresearch.fidelity.com/prospectus/sec |
| Expenses [Text Block] | What were your Fund costs for the last year? (based on hypothetical $10,000 investment) FUND COST (PREVIOUS YEAR) Costs of a $10,000 investment Costs paid as a percentage of a $10,000 investment Class Z $ 0.54 % |
| Expenses Paid, Amount | $ 63 |
| Expense Ratio, Percent | 0.54% |
| Factors Affecting Performance [Text Block] | What affected the Fund's performance this period? • • • • • • |
| Performance Past Does Not Indicate Future [Text] | The Fund's past performance is not a good predictor of the Fund's future performance.</span>" id="sjs-B117"><span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:italic;font-weight:normal;">The Fund's past performance is not a good predictor of the Fund's future performance.</span> |
| Line Graph [Table Text Block] | How did the Fund perform over the past 10 years? CUMULATIVE PERFORMANCE December 31, 2014 through December 31, 2024. Initial investment of $10,000. Class Z $10,000 $10,278 $10,964 $14,088 $13,520 $17,523 $21,744 $27,134 $19,750 $26,945 $36,483 S&P 500® Index $10,000 $10,138 $11,351 $13,829 $13,223 $17,386 $20,585 $26,494 $21,696 $27,399 $34,254 2014 2015 2016 2017 2018 2019 2020 2021 2022 2023 2024 |
| Average Annual Return [Table Text Block] | AVERAGE ANNUAL TOTAL RETURNS: 1 Year 5 Year 10 Year Class Z 35.40% 15.80% 13.82% S&P 500® Index 25.02% 14.53% 13.10% Visit institutional.fidelity.com for more recent performance information. The Fund's past performance is not a good predictor of the Fund's future performance. The graph and table do not reflect the deduction of taxes that a shareholder would pay on fund distributions or redemption of fund shares. |
| 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. |
| Net Assets | $ 21,798,939,502 |
| Holdings Count | shares | 443 |
| Advisory Fees Paid, Amount | $ 125,752,187 |
| Investment Company Portfolio Turnover | 18% |
| Additional Fund Statistics [Text Block] | Key Fund Statistics (as of December 31, 2024) KEY FACTS Fund Size $ Number of Holdings 443 Total Advisory Fee $ Portfolio Turnover 18 % |
| Holdings [Text Block] | MARKET SECTORS (% of Fund's net assets) Information Technology 26.0 Communication Services 21.4 Financials 14.8 Industrials 12.3 Consumer Discretionary 11.4 Health Care 8.3 Materials 1.5 Energy 1.5 Utilities 1.2 Consumer Staples 1.2 Real Estate 0.0 Common Stocks 96.9 Preferred Stocks 2.7 Preferred Securities 0.0 Short-Term Investments and Net Other Assets (Liabilities) 0.4 ASSET ALLOCATION (% of Fund's net assets) Common Stocks - 96.9 Preferred Stocks - 2.7 Preferred Securities - 0.0 Short-Term Investments and Net Other Assets (Liabilities) - 0.4 United States 92.9 Canada 1.9 Taiwan 0.7 Netherlands 0.6 United Kingdom 0.5 China 0.4 Italy 0.4 Congo Democratic Republic Of 0.4 Korea (South) 0.4 Others 1.8 GEOGRAPHIC DIVERSIFICATION (% of Fund's net assets) United States - 92.9 Canada - 1.9 Taiwan - 0.7 Netherlands - 0.6 United Kingdom - 0.5 China - 0.4 Italy - 0.4 Congo Democratic Republic Of - 0.4 Korea (South) - 0.4 Others - 1.8 |
| Largest Holdings [Text Block] | TOP HOLDINGS (% of Fund's net assets) Meta Platforms Inc Class A 11.7 NVIDIA Corp 8.9 Microsoft Corp 6.5 Alphabet Inc Class A 6.1 Amazon.com Inc 5.8 Berkshire Hathaway Inc Class A 5.1 Apple Inc 2.6 Netflix Inc 2.6 Space Exploration Technologies Corp 2.3 Eli Lilly & Co 2.2 53.8 |
| Material Fund Change [Text Block] | How has the Fund changed? This is a summary of certain changes to the Fund since January 1, 2024. For more complete information, you may review the Fund's next prospectus, which we expect to be available by March 1, 2025 at fundresearch.fidelity.com/prospectus/sec or upon request at 1-877-208-0098 or by sending an e-mail to fidfunddocuments fidelity.com . The fees associated with this class changed during the reporting year. The variations in class fees are primarily the result of the following changes: Management fee Operating expenses Performance adjustment fee The fund's transfer agent and pricing & bookkeeping fees were changed to a fixed rate effective December 1, 2023. Effective March 1, 2024, the fund's management contract was amended to incorporate administrative services previously covered under separate services agreements (transfer agent and pricing & bookkeeping). The amended contract incorporates a basic fee rate that may vary by class (subject to a performance adjustment). The Adviser or an affiliate pays certain expenses of managing and operating the fund out of each class's management fee. |
| Material Fund Change Expenses [Text Block] | The fees associated with this class changed during the reporting year. The variations in class fees are primarily the result of the following changes: Management fee Operating expenses Performance adjustment fee The fund's transfer agent and pricing & bookkeeping fees were changed to a fixed rate effective December 1, 2023. Effective March 1, 2024, the fund's management contract was amended to incorporate administrative services previously covered under separate services agreements (transfer agent and pricing & bookkeeping). The amended contract incorporates a basic fee rate that may vary by class (subject to a performance adjustment). The Adviser or an affiliate pays certain expenses of managing and operating the fund out of each class's management fee. |
| Summary of Change Legend [Text Block] | This is a summary of certain changes to the Fund since January 1, 2024. For more complete information, you may review the Fund's next prospectus, which we expect to be available by March 1, 2025 at fundresearch.fidelity.com/prospectus/sec or upon request at 1-877-208-0098 or by sending an e-mail to fidfunddocuments fidelity.com . |
| Updated Prospectus Phone Number | 1-877-208-0098</span>" id="sjs-B131"><span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;">1-877-208-0098</span> |
| Updated Prospectus Email Address | fidfunddocuments@fidelity.com</span>" id="sjs-B132"><span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;">fidfunddocuments@fidelity.com</span> |
| Updated Prospectus Web Address | fundresearch.fidelity.com/prospectus/sec</span>" id="sjs-B133"><span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;">fundresearch.fidelity.com/prospectus/sec</span> |
| Fidelity Advisor New Insights Fund - Class M | |
| Shareholder Report [Line Items] | |
| Fund Name | Fidelity Advisor® New Insights Fund |
| Class Name | Fidelity Advisor® New Insights Fund Class M |
| Trading Symbol | FNITX |
| Annual or Semi-Annual Statement [Text Block] | This annual shareholder report contains information about Fidelity Advisor® New Insights Fund for the period 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 fundresearch.fidelity.com/prospectus/sec. You can also request this information by contacting us at 1-877-208-0098 or by sending an e-mail to fidfunddocuments@fidelity.com. |
| Material Fund Change Notice [Text Block] | This report describes changes to the Fund that occurred during the reporting period. |
| Additional Information Phone Number | 1-877-208-0098 |
| Additional Information Email | fidfunddocuments@fidelity.com |
| Additional Information Website | fundresearch.fidelity.com/prospectus/sec |
| Expenses [Text Block] | What were your Fund costs for the last year? (based on hypothetical $10,000 investment) FUND COST (PREVIOUS YEAR) Costs of a $10,000 investment Costs paid as a percentage of a $10,000 investment Class M $ 1.15 % |
| Expenses Paid, Amount | $ 135 |
| Expense Ratio, Percent | 1.15% |
| Factors Affecting Performance [Text Block] | What affected the Fund's performance this period? • • • • • • |
| Performance Past Does Not Indicate Future [Text] | The Fund's past performance is not a good predictor of the Fund's future performance.</span>" id="sjs-B150"><span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:italic;font-weight:normal;">The Fund's past performance is not a good predictor of the Fund's future performance.</span> |
| Line Graph [Table Text Block] | How did the Fund perform over the past 10 years? CUMULATIVE PERFORMANCE December 31, 2014 through December 31, 2024. Initial investment of $10,000 and the current sales charge was paid. Class M $9,650 $9,857 $10,449 $13,339 $12,720 $16,383 $20,205 $25,053 $18,128 $24,580 $33,077 S&P 500® Index $10,000 $10,138 $11,351 $13,829 $13,223 $17,386 $20,585 $26,494 $21,696 $27,399 $34,254 2014 2015 2016 2017 2018 2019 2020 2021 2022 2023 2024 |
| Average Annual Return [Table Text Block] | AVERAGE ANNUAL TOTAL RETURNS: 1 Year 5 Year 10 Year Class M (incl. 3.50% sales charge) 29.86% 14.27% 12.71% Class M (without 3.50% sales charge) 34.57% 15.09% 13.11% S&P 500® Index 25.02% 14.53% 13.10% Visit institutional.fidelity.com for more recent performance information. The Fund's past performance is not a good predictor of the Fund's future performance. The graph and table do not reflect the deduction of taxes that a shareholder would pay on fund distributions or redemption of fund shares. |
| 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. |
| Net Assets | $ 21,798,939,502 |
| Holdings Count | shares | 443 |
| Advisory Fees Paid, Amount | $ 125,752,187 |
| Investment Company Portfolio Turnover | 18% |
| Additional Fund Statistics [Text Block] | Key Fund Statistics (as of December 31, 2024) KEY FACTS Fund Size $ Number of Holdings 443 Total Advisory Fee $ Portfolio Turnover 18 % |
| Holdings [Text Block] | MARKET SECTORS (% of Fund's net assets) Information Technology 26.0 Communication Services 21.4 Financials 14.8 Industrials 12.3 Consumer Discretionary 11.4 Health Care 8.3 Materials 1.5 Energy 1.5 Utilities 1.2 Consumer Staples 1.2 Real Estate 0.0 Common Stocks 96.9 Preferred Stocks 2.7 Preferred Securities 0.0 Short-Term Investments and Net Other Assets (Liabilities) 0.4 ASSET ALLOCATION (% of Fund's net assets) Common Stocks - 96.9 Preferred Stocks - 2.7 Preferred Securities - 0.0 Short-Term Investments and Net Other Assets (Liabilities) - 0.4 United States 92.9 Canada 1.9 Taiwan 0.7 Netherlands 0.6 United Kingdom 0.5 China 0.4 Italy 0.4 Congo Democratic Republic Of 0.4 Korea (South) 0.4 Others 1.8 GEOGRAPHIC DIVERSIFICATION (% of Fund's net assets) United States - 92.9 Canada - 1.9 Taiwan - 0.7 Netherlands - 0.6 United Kingdom - 0.5 China - 0.4 Italy - 0.4 Congo Democratic Republic Of - 0.4 Korea (South) - 0.4 Others - 1.8 |
| Largest Holdings [Text Block] | TOP HOLDINGS (% of Fund's net assets) Meta Platforms Inc Class A 11.7 NVIDIA Corp 8.9 Microsoft Corp 6.5 Alphabet Inc Class A 6.1 Amazon.com Inc 5.8 Berkshire Hathaway Inc Class A 5.1 Apple Inc 2.6 Netflix Inc 2.6 Space Exploration Technologies Corp 2.3 Eli Lilly & Co 2.2 53.8 |
| Material Fund Change [Text Block] | How has the Fund changed? This is a summary of certain changes to the Fund since January 1, 2024. For more complete information, you may review the Fund's next prospectus, which we expect to be available by March 1, 2025 at fundresearch.fidelity.com/prospectus/sec or upon request at 1-877-208-0098 or by sending an e-mail to fidfunddocuments fidelity.com . The fees associated with this class changed during the reporting year. The variations in class fees are primarily the result of the following changes: Management fee Operating expenses Performance adjustment fee The fund's transfer agent and pricing & bookkeeping fees were changed to a fixed rate effective December 1, 2023. Effective March 1, 2024, the fund's management contract was amended to incorporate administrative services previously covered under separate services agreements (transfer agent and pricing & bookkeeping). The amended contract incorporates a basic fee rate that may vary by class (subject to a performance adjustment). The Adviser or an affiliate pays certain expenses of managing and operating the fund out of each class's management fee. |
| Material Fund Change Expenses [Text Block] | The fees associated with this class changed during the reporting year. The variations in class fees are primarily the result of the following changes: Management fee Operating expenses Performance adjustment fee The fund's transfer agent and pricing & bookkeeping fees were changed to a fixed rate effective December 1, 2023. Effective March 1, 2024, the fund's management contract was amended to incorporate administrative services previously covered under separate services agreements (transfer agent and pricing & bookkeeping). The amended contract incorporates a basic fee rate that may vary by class (subject to a performance adjustment). The Adviser or an affiliate pays certain expenses of managing and operating the fund out of each class's management fee. |
| Summary of Change Legend [Text Block] | This is a summary of certain changes to the Fund since January 1, 2024. For more complete information, you may review the Fund's next prospectus, which we expect to be available by March 1, 2025 at fundresearch.fidelity.com/prospectus/sec or upon request at 1-877-208-0098 or by sending an e-mail to fidfunddocuments fidelity.com . |
| Updated Prospectus Phone Number | 1-877-208-0098</span>" id="sjs-B164"><span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;">1-877-208-0098</span> |
| Updated Prospectus Email Address | fidfunddocuments@fidelity.com</span>" id="sjs-B165"><span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;">fidfunddocuments@fidelity.com</span> |
| Updated Prospectus Web Address | fundresearch.fidelity.com/prospectus/sec</span>" id="sjs-B166"><span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;">fundresearch.fidelity.com/prospectus/sec</span> |
| Fidelity Contrafund | |
| Shareholder Report [Line Items] | |
| Fund Name | Fidelity® Contrafund® |
| Class Name | Fidelity® Contrafund® |
| Trading Symbol | FCNTX |
| Annual or Semi-Annual Statement [Text Block] | This annual shareholder report contains information about Fidelity® Contrafund® for the period 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 fundresearch.fidelity.com/prospectus/sec. You can also request this information by contacting us at 1-800-544-8544 or by sending an e-mail to fidfunddocuments@fidelity.com. |
| Material Fund Change Notice [Text Block] | This report describes changes to the Fund that occurred during the reporting period. |
| Additional Information Phone Number | 1-800-544-8544 |
| Additional Information Email | fidfunddocuments@fidelity.com |
| Additional Information Website | fundresearch.fidelity.com/prospectus/sec |
| Expenses [Text Block] | What were your Fund costs for the last year? (based on hypothetical $10,000 investment) FUND COST (PREVIOUS YEAR) Costs of a $10,000 investment Costs paid as a percentage of a $10,000 investment Fidelity® Contrafund® $ 0.63 % |
| Expenses Paid, Amount | $ 74 |
| Expense Ratio, Percent | 0.63% |
| Factors Affecting Performance [Text Block] | What affected the Fund's performance this period? • • • • • • |
| Performance Past Does Not Indicate Future [Text] | The Fund's past performance is not a good predictor of the Fund's future performance.</span>" id="sjs-B183"><span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:italic;font-weight:normal;">The Fund's past performance is not a good predictor of the Fund's future performance.</span> |
| Line Graph [Table Text Block] | How did the Fund perform over the past 10 years? CUMULATIVE PERFORMANCE December 31, 2014 through December 31, 2024. Initial investment of $10,000. Fidelity® Contrafund® $10,000 $10,646 $11,004 $14,549 $14,239 $18,509 $24,539 $30,517 $21,892 $30,503 $41,476 S&P 500® Index $10,000 $10,138 $11,351 $13,829 $13,223 $17,386 $20,585 $26,494 $21,696 $27,399 $34,254 2014 2015 2016 2017 2018 2019 2020 2021 2022 2023 2024 |
| Average Annual Return [Table Text Block] | AVERAGE ANNUAL TOTAL RETURNS: 1 Year 5 Year 10 Year Fidelity® Contrafund® 35.97% 17.51% 15.29% S&P 500® Index 25.02% 14.53% 13.10% Visit www.fidelity.com for more recent performance information. The Fund's past performance is not a good predictor of the Fund's future performance. The graph and table do not reflect the deduction of taxes that a shareholder would pay on fund distributions or redemption of fund shares. |
| 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. |
| Net Assets | $ 152,766,525,549 |
| Holdings Count | shares | 389 |
| Advisory Fees Paid, Amount | $ 851,690,132 |
| Investment Company Portfolio Turnover | 18% |
| Additional Fund Statistics [Text Block] | Key Fund Statistics (as of December 31, 2024) KEY FACTS Fund Size $ Number of Holdings 389 Total Advisory Fee $ Portfolio Turnover 18 % |
| Holdings [Text Block] | MARKET SECTORS (% of Fund's net assets) Information Technology 24.4 Communication Services 23.6 Financials 18.0 Consumer Discretionary 10.8 Health Care 8.7 Industrials 7.9 Consumer Staples 1.7 Energy 1.2 Materials 1.0 Utilities 0.7 Real Estate 0.1 Common Stocks 96.3 Preferred Stocks 1.8 Preferred Securities 0.0 Short-Term Investments and Net Other Assets (Liabilities) 1.9 ASSET ALLOCATION (% of Fund's net assets) Common Stocks - 96.3 Preferred Stocks - 1.8 Preferred Securities - 0.0 Short-Term Investments and Net Other Assets (Liabilities) - 1.9 United States 94.6 Canada 1.7 Congo Democratic Republic Of 0.5 Taiwan 0.4 Switzerland 0.4 Israel 0.3 United Kingdom 0.3 Brazil 0.3 Netherlands 0.3 Others 1.2 GEOGRAPHIC DIVERSIFICATION (% of Fund's net assets) United States - 94.6 Canada - 1.7 Congo Democratic Republic Of - 0.5 Taiwan - 0.4 Switzerland - 0.4 Israel - 0.3 United Kingdom - 0.3 Brazil - 0.3 Netherlands - 0.3 Others - 1.2 |
| Largest Holdings [Text Block] | TOP HOLDINGS (% of Fund's net assets) Meta Platforms Inc Class A 15.8 NVIDIA Corp 8.5 Berkshire Hathaway Inc Class A 8.4 Amazon.com Inc 6.8 Microsoft Corp 5.4 Apple Inc 3.4 Eli Lilly & Co 2.6 Alphabet Inc Class A 2.5 Netflix Inc 2.4 Alphabet Inc Class C 2.0 57.8 |
| Material Fund Change [Text Block] | How has the Fund changed? This is a summary of certain changes to the Fund since January 1, 2024. For more complete information, you may review the Fund's next prospectus, which we expect to be available by March 1, 2025 at fundresearch.fidelity.com/prospectus/sec or upon request at 1-800-544-8544 or by sending an e-mail to fidfunddocuments fidelity.com . The fees associated with this class changed during the reporting year. The variations in class fees are primarily the result of the following changes: Management fee Performance adjustment fee The fund's transfer agent and pricing & bookkeeping fees were changed to a fixed rate effective December 1, 2023. Effective March 1, 2024, the fund's management contract was amended to incorporate administrative services previously covered under separate services agreements (transfer agent and pricing & bookkeeping). The amended contract incorporates a basic fee rate that may vary by class (subject to a performance adjustment). The Adviser or an affiliate pays certain expenses of managing and operating the fund out of each class's management fee. |
| Material Fund Change Expenses [Text Block] | The fees associated with this class changed during the reporting year. The variations in class fees are primarily the result of the following changes: Management fee Performance adjustment fee The fund's transfer agent and pricing & bookkeeping fees were changed to a fixed rate effective December 1, 2023. Effective March 1, 2024, the fund's management contract was amended to incorporate administrative services previously covered under separate services agreements (transfer agent and pricing & bookkeeping). The amended contract incorporates a basic fee rate that may vary by class (subject to a performance adjustment). The Adviser or an affiliate pays certain expenses of managing and operating the fund out of each class's management fee. |
| Summary of Change Legend [Text Block] | This is a summary of certain changes to the Fund since January 1, 2024. For more complete information, you may review the Fund's next prospectus, which we expect to be available by March 1, 2025 at fundresearch.fidelity.com/prospectus/sec or upon request at 1-800-544-8544 or by sending an e-mail to fidfunddocuments fidelity.com . |
| Updated Prospectus Phone Number | 1-800-544-8544</span>" id="sjs-B197"><span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;">1-800-544-8544</span> |
| Updated Prospectus Email Address | fidfunddocuments@fidelity.com</span>" id="sjs-B198"><span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;">fidfunddocuments@fidelity.com</span> |
| Updated Prospectus Web Address | fundresearch.fidelity.com/prospectus/sec</span>" id="sjs-B199"><span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;">fundresearch.fidelity.com/prospectus/sec</span> |
| Fidelity Contrafund K6 | |
| Shareholder Report [Line Items] | |
| Fund Name | Fidelity® Contrafund® K6 |
| Class Name | Fidelity® Contrafund® K6 |
| Trading Symbol | FLCNX |
| Annual or Semi-Annual Statement [Text Block] | This annual shareholder report contains information about Fidelity® Contrafund® K6 for the period 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 fundresearch.fidelity.com/prospectus/sec. You can also request this information by contacting us at 1-800-835-5092 or by sending an e-mail to fidfunddocuments@fidelity.com. |
| Additional Information Phone Number | 1-800-835-5092 |
| Additional Information Email | fidfunddocuments@fidelity.com |
| Additional Information Website | fundresearch.fidelity.com/prospectus/sec |
| Expenses [Text Block] | What were your Fund costs for the last year? (based on hypothetical $10,000 investment) FUND COST (PREVIOUS YEAR) Costs of a $10,000 investment Costs paid as a percentage of a $10,000 investment Fidelity® Contrafund® K6 $ 0.45 % |
| Expenses Paid, Amount | $ 53 |
| Expense Ratio, Percent | 0.45% |
| Factors Affecting Performance [Text Block] | What affected the Fund's performance this period? • • • • • • |
| Performance Past Does Not Indicate Future [Text] | The Fund's past performance is not a good predictor of the Fund's future performance.</span>" id="sjs-B215"><span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:italic;font-weight:normal;">The Fund's past performance is not a good predictor of the Fund's future performance.</span> |
| Line Graph [Table Text Block] | How did the Fund perform over the life of Fund? CUMULATIVE PERFORMANCE May 25, 2017 through December 31, 2024. Initial investment of $10,000. Fidelity® Contrafund® K6 $10,000 $11,377 $11,132 $14,584 $19,080 $23,685 $17,262 $23,764 S&P 500® Index $10,000 $11,202 $10,710 $14,083 $16,674 $21,460 $17,574 $22,193 2017 2018 2019 2020 2021 2022 2023 2024 |
| Average Annual Return [Table Text Block] | AVERAGE ANNUAL TOTAL RETURNS: 1 Year 5 Year Life of Fund A Fidelity® Contrafund® K6 35.37% 17.14% 16.60% S&P 500® Index 25.02% 14.53% 14.35% A From May 25, 2017 Visit www.401k.com for more recent performance information. The Fund's past performance is not a good predictor of the Fund's future performance. The graph and table do not reflect the deduction of taxes that a shareholder would pay on fund distributions or redemption of fund shares. |
| Performance Inception Date | May 25, 2017 |
| 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. |
| Net Assets | $ 34,782,795,541 |
| Holdings Count | shares | 383 |
| Advisory Fees Paid, Amount | $ 152,941,850 |
| Investment Company Portfolio Turnover | 19% |
| Additional Fund Statistics [Text Block] | Key Fund Statistics (as of December 31, 2024) KEY FACTS Fund Size $ Number of Holdings 383 Total Advisory Fee $ Portfolio Turnover 19 % |
| Holdings [Text Block] | MARKET SECTORS (% of Fund's net assets) Information Technology 26.2 Communication Services 22.8 Financials 17.8 Consumer Discretionary 10.3 Health Care 9.2 Industrials 7.5 Consumer Staples 1.8 Energy 1.3 Materials 1.1 Utilities 0.8 Real Estate 0.1 Common Stocks 97.8 Preferred Stocks 1.1 Preferred Securities 0.0 Short-Term Investments and Net Other Assets (Liabilities) 1.1 ASSET ALLOCATION (% of Fund's net assets) Common Stocks - 97.8 Preferred Stocks - 1.1 Preferred Securities - 0.0 Short-Term Investments and Net Other Assets (Liabilities) - 1.1 United States 94.4 Canada 1.9 Congo Democratic Republic Of 0.5 Taiwan 0.4 Israel 0.3 Switzerland 0.3 Brazil 0.3 United Kingdom 0.3 Netherlands 0.3 Others 1.3 GEOGRAPHIC DIVERSIFICATION (% of Fund's net assets) United States - 94.4 Canada - 1.9 Congo Democratic Republic Of - 0.5 Taiwan - 0.4 Israel - 0.3 Switzerland - 0.3 Brazil - 0.3 United Kingdom - 0.3 Netherlands - 0.3 Others - 1.3 |
| Largest Holdings [Text Block] | TOP HOLDINGS (% of Fund's net assets) Meta Platforms Inc Class A 14.9 NVIDIA Corp 9.5 Berkshire Hathaway Inc Class A 7.7 Amazon.com Inc 6.0 Microsoft Corp 5.6 Apple Inc 3.5 Eli Lilly & Co 2.7 Alphabet Inc Class A 2.5 Netflix Inc 2.5 Alphabet Inc Class C 2.0 56.9 |
| Fidelity Contrafund - Class K | |
| Shareholder Report [Line Items] | |
| Fund Name | Fidelity® Contrafund® |
| Class Name | Fidelity® Contrafund® Class K |
| Trading Symbol | FCNKX |
| Annual or Semi-Annual Statement [Text Block] | This annual shareholder report contains information about Fidelity® Contrafund® for the period 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 fundresearch.fidelity.com/prospectus/sec. You can also request this information by contacting us at 1-800-835-5092 or by sending an e-mail to fidfunddocuments@fidelity.com. |
| Material Fund Change Notice [Text Block] | This report describes changes to the Fund that occurred during the reporting period. |
| Additional Information Phone Number | 1-800-835-5092 |
| Additional Information Email | fidfunddocuments@fidelity.com |
| Additional Information Website | fundresearch.fidelity.com/prospectus/sec |
| Expenses [Text Block] | What were your Fund costs for the last year? (based on hypothetical $10,000 investment) FUND COST (PREVIOUS YEAR) Costs of a $10,000 investment Costs paid as a percentage of a $10,000 investment Class K $ 0.56 % |
| Expenses Paid, Amount | $ 66 |
| Expense Ratio, Percent | 0.56% |
| Factors Affecting Performance [Text Block] | What affected the Fund's performance this period? • • • • • • |
| Performance Past Does Not Indicate Future [Text] | The Fund's past performance is not a good predictor of the Fund's future performance.</span>" id="sjs-B243"><span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:italic;font-weight:normal;">The Fund's past performance is not a good predictor of the Fund's future performance.</span> |
| Line Graph [Table Text Block] | How did the Fund perform over the past 10 years? CUMULATIVE PERFORMANCE December 31, 2014 through December 31, 2024. Initial investment of $10,000. Class K $10,000 $10,655 $11,026 $14,592 $14,290 $18,601 $24,681 $30,709 $22,043 $30,743 $41,827 S&P 500® Index $10,000 $10,138 $11,351 $13,829 $13,223 $17,386 $20,585 $26,494 $21,696 $27,399 $34,254 2014 2015 2016 2017 2018 2019 2020 2021 2022 2023 2024 |
| Average Annual Return [Table Text Block] | AVERAGE ANNUAL TOTAL RETURNS: 1 Year 5 Year 10 Year Class K 36.05% 17.59% 15.38% S&P 500® Index 25.02% 14.53% 13.10% Visit www.401k.com for more recent performance information. The Fund's past performance is not a good predictor of the Fund's future performance. The graph and table do not reflect the deduction of taxes that a shareholder would pay on fund distributions or redemption of fund shares. |
| 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. |
| Net Assets | $ 152,766,525,549 |
| Holdings Count | shares | 389 |
| Advisory Fees Paid, Amount | $ 851,690,132 |
| Investment Company Portfolio Turnover | 18% |
| Additional Fund Statistics [Text Block] | Key Fund Statistics (as of December 31, 2024) KEY FACTS Fund Size $ Number of Holdings 389 Total Advisory Fee $ Portfolio Turnover 18 % |
| Holdings [Text Block] | MARKET SECTORS (% of Fund's net assets) Information Technology 24.4 Communication Services 23.6 Financials 18.0 Consumer Discretionary 10.8 Health Care 8.7 Industrials 7.9 Consumer Staples 1.7 Energy 1.2 Materials 1.0 Utilities 0.7 Real Estate 0.1 Common Stocks 96.3 Preferred Stocks 1.8 Preferred Securities 0.0 Short-Term Investments and Net Other Assets (Liabilities) 1.9 ASSET ALLOCATION (% of Fund's net assets) Common Stocks - 96.3 Preferred Stocks - 1.8 Preferred Securities - 0.0 Short-Term Investments and Net Other Assets (Liabilities) - 1.9 United States 94.6 Canada 1.7 Congo Democratic Republic Of 0.5 Taiwan 0.4 Switzerland 0.4 Israel 0.3 United Kingdom 0.3 Brazil 0.3 Netherlands 0.3 Others 1.2 GEOGRAPHIC DIVERSIFICATION (% of Fund's net assets) United States - 94.6 Canada - 1.7 Congo Democratic Republic Of - 0.5 Taiwan - 0.4 Switzerland - 0.4 Israel - 0.3 United Kingdom - 0.3 Brazil - 0.3 Netherlands - 0.3 Others - 1.2 |
| Largest Holdings [Text Block] | TOP HOLDINGS (% of Fund's net assets) Meta Platforms Inc Class A 15.8 NVIDIA Corp 8.5 Berkshire Hathaway Inc Class A 8.4 Amazon.com Inc 6.8 Microsoft Corp 5.4 Apple Inc 3.4 Eli Lilly & Co 2.6 Alphabet Inc Class A 2.5 Netflix Inc 2.4 Alphabet Inc Class C 2.0 57.8 |
| Material Fund Change [Text Block] | How has the Fund changed? This is a summary of certain changes to the Fund since January 1, 2024. For more complete information, you may review the Fund's next prospectus, which we expect to be available by March 1, 2025 at fundresearch.fidelity.com/prospectus/sec or upon request at 1-800-835-5092 or by sending an e-mail to fidfunddocuments fidelity.com . The fees associated with this class changed during the reporting year. The variations in class fees are primarily the result of the following changes: Management fee Performance adjustment fee The fund's transfer agent and pricing & bookkeeping fees were changed to a fixed rate effective December 1, 2023. Effective March 1, 2024, the fund's management contract was amended to incorporate administrative services previously covered under separate services agreements (transfer agent and pricing & bookkeeping). The amended contract incorporates a basic fee rate that may vary by class (subject to a performance adjustment). The Adviser or an affiliate pays certain expenses of managing and operating the fund out of each class's management fee. |
| Material Fund Change Expenses [Text Block] | The fees associated with this class changed during the reporting year. The variations in class fees are primarily the result of the following changes: Management fee Performance adjustment fee The fund's transfer agent and pricing & bookkeeping fees were changed to a fixed rate effective December 1, 2023. Effective March 1, 2024, the fund's management contract was amended to incorporate administrative services previously covered under separate services agreements (transfer agent and pricing & bookkeeping). The amended contract incorporates a basic fee rate that may vary by class (subject to a performance adjustment). The Adviser or an affiliate pays certain expenses of managing and operating the fund out of each class's management fee. |
| Summary of Change Legend [Text Block] | This is a summary of certain changes to the Fund since January 1, 2024. For more complete information, you may review the Fund's next prospectus, which we expect to be available by March 1, 2025 at fundresearch.fidelity.com/prospectus/sec or upon request at 1-800-835-5092 or by sending an e-mail to fidfunddocuments fidelity.com . |
| Updated Prospectus Phone Number | 1-800-835-5092</span>" id="sjs-B257"><span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;">1-800-835-5092</span> |
| Updated Prospectus Email Address | fidfunddocuments@fidelity.com</span>" id="sjs-B258"><span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;">fidfunddocuments@fidelity.com</span> |
| Updated Prospectus Web Address | fundresearch.fidelity.com/prospectus/sec</span>" id="sjs-B259"><span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;">fundresearch.fidelity.com/prospectus/sec</span> |
| Fidelity Advisor New Insights Fund - Class A | |
| Shareholder Report [Line Items] | |
| Fund Name | Fidelity Advisor® New Insights Fund |
| Class Name | Fidelity Advisor® New Insights Fund Class A |
| Trading Symbol | FNIAX |
| Annual or Semi-Annual Statement [Text Block] | This annual shareholder report contains information about Fidelity Advisor® New Insights Fund for the period 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 fundresearch.fidelity.com/prospectus/sec. You can also request this information by contacting us at 1-877-208-0098 or by sending an e-mail to fidfunddocuments@fidelity.com. |
| Material Fund Change Notice [Text Block] | This report describes changes to the Fund that occurred during the reporting period. |
| Additional Information Phone Number | 1-877-208-0098 |
| Additional Information Email | fidfunddocuments@fidelity.com |
| Additional Information Website | fundresearch.fidelity.com/prospectus/sec |
| Expenses [Text Block] | What were your Fund costs for the last year? (based on hypothetical $10,000 investment) FUND COST (PREVIOUS YEAR) Costs of a $10,000 investment Costs paid as a percentage of a $10,000 investment Class A $ 0.90 % |
| Expenses Paid, Amount | $ 106 |
| Expense Ratio, Percent | 0.90% |
| Factors Affecting Performance [Text Block] | What affected the Fund's performance this period? • • • • • • |
| Performance Past Does Not Indicate Future [Text] | The Fund's past performance is not a good predictor of the Fund's future performance.</span>" id="sjs-B276"><span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:italic;font-weight:normal;">The Fund's past performance is not a good predictor of the Fund's future performance.</span> |
| Line Graph [Table Text Block] | How did the Fund perform over the past 10 years? CUMULATIVE PERFORMANCE December 31, 2014 through December 31, 2024. Initial investment of $10,000 and the current sales charge was paid. Class A $9,425 $9,650 $10,258 $13,129 $12,548 $16,206 $20,036 $24,906 $18,062 $24,555 $33,126 S&P 500® Index $10,000 $10,138 $11,351 $13,829 $13,223 $17,386 $20,585 $26,494 $21,696 $27,399 $34,254 2014 2015 2016 2017 2018 2019 2020 2021 2022 2023 2024 |
| Average Annual Return [Table Text Block] | AVERAGE ANNUAL TOTAL RETURNS: 1 Year 5 Year 10 Year Class A (incl. 5.75% sales charge) 27.15% 14.01% 12.72% Class A (without 5.75% sales charge) 34.91% 15.37% 13.39% S&P 500® Index 25.02% 14.53% 13.10% Visit institutional.fidelity.com for more recent performance information. The Fund's past performance is not a good predictor of the Fund's future performance. The graph and table do not reflect the deduction of taxes that a shareholder would pay on fund distributions or redemption of fund shares. |
| 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. |
| Net Assets | $ 21,798,939,502 |
| Holdings Count | shares | 443 |
| Advisory Fees Paid, Amount | $ 125,752,187 |
| Investment Company Portfolio Turnover | 18% |
| Additional Fund Statistics [Text Block] | Key Fund Statistics (as of December 31, 2024) KEY FACTS Fund Size $ Number of Holdings 443 Total Advisory Fee $ Portfolio Turnover 18 % |
| Holdings [Text Block] | MARKET SECTORS (% of Fund's net assets) Information Technology 26.0 Communication Services 21.4 Financials 14.8 Industrials 12.3 Consumer Discretionary 11.4 Health Care 8.3 Materials 1.5 Energy 1.5 Utilities 1.2 Consumer Staples 1.2 Real Estate 0.0 Common Stocks 96.9 Preferred Stocks 2.7 Preferred Securities 0.0 Short-Term Investments and Net Other Assets (Liabilities) 0.4 ASSET ALLOCATION (% of Fund's net assets) Common Stocks - 96.9 Preferred Stocks - 2.7 Preferred Securities - 0.0 Short-Term Investments and Net Other Assets (Liabilities) - 0.4 United States 92.9 Canada 1.9 Taiwan 0.7 Netherlands 0.6 United Kingdom 0.5 China 0.4 Italy 0.4 Congo Democratic Republic Of 0.4 Korea (South) 0.4 Others 1.8 GEOGRAPHIC DIVERSIFICATION (% of Fund's net assets) United States - 92.9 Canada - 1.9 Taiwan - 0.7 Netherlands - 0.6 United Kingdom - 0.5 China - 0.4 Italy - 0.4 Congo Democratic Republic Of - 0.4 Korea (South) - 0.4 Others - 1.8 |
| Largest Holdings [Text Block] | TOP HOLDINGS (% of Fund's net assets) Meta Platforms Inc Class A 11.7 NVIDIA Corp 8.9 Microsoft Corp 6.5 Alphabet Inc Class A 6.1 Amazon.com Inc 5.8 Berkshire Hathaway Inc Class A 5.1 Apple Inc 2.6 Netflix Inc 2.6 Space Exploration Technologies Corp 2.3 Eli Lilly & Co 2.2 53.8 |
| Material Fund Change [Text Block] | How has the Fund changed? This is a summary of certain changes to the Fund since January 1, 2024. For more complete information, you may review the Fund's next prospectus, which we expect to be available by March 1, 2025 at fundresearch.fidelity.com/prospectus/sec or upon request at 1-877-208-0098 or by sending an e-mail to fidfunddocuments fidelity.com . The fees associated with this class changed during the reporting year. The variations in class fees are primarily the result of the following changes: Management fee Operating expenses Performance adjustment fee The fund's transfer agent and pricing & bookkeeping fees were changed to a fixed rate effective December 1, 2023. Effective March 1, 2024, the fund's management contract was amended to incorporate administrative services previously covered under separate services agreements (transfer agent and pricing & bookkeeping). The amended contract incorporates a basic fee rate that may vary by class (subject to a performance adjustment). The Adviser or an affiliate pays certain expenses of managing and operating the fund out of each class's management fee. |
| Material Fund Change Expenses [Text Block] | The fees associated with this class changed during the reporting year. The variations in class fees are primarily the result of the following changes: Management fee Operating expenses Performance adjustment fee The fund's transfer agent and pricing & bookkeeping fees were changed to a fixed rate effective December 1, 2023. Effective March 1, 2024, the fund's management contract was amended to incorporate administrative services previously covered under separate services agreements (transfer agent and pricing & bookkeeping). The amended contract incorporates a basic fee rate that may vary by class (subject to a performance adjustment). The Adviser or an affiliate pays certain expenses of managing and operating the fund out of each class's management fee. |
| Summary of Change Legend [Text Block] | This is a summary of certain changes to the Fund since January 1, 2024. For more complete information, you may review the Fund's next prospectus, which we expect to be available by March 1, 2025 at fundresearch.fidelity.com/prospectus/sec or upon request at 1-877-208-0098 or by sending an e-mail to fidfunddocuments fidelity.com . |
| Updated Prospectus Phone Number | 1-877-208-0098</span>" id="sjs-B290"><span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;">1-877-208-0098</span> |
| Updated Prospectus Email Address | fidfunddocuments@fidelity.com</span>" id="sjs-B291"><span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;">fidfunddocuments@fidelity.com</span> |
| Updated Prospectus Web Address | fundresearch.fidelity.com/prospectus/sec</span>" id="sjs-B292"><span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;">fundresearch.fidelity.com/prospectus/sec</span> |
| Shareholder Report, Line Graph (Details) - USD ($) | 12 Months Ended | 60 Months Ended | 96 Months Ended | 120 Months Ended | 132 Months Ended | ||||||||||
| Dec. 31, 2024 | Dec. 31, 2024 | 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 | |
| C000016598_0_BBIndexMember_1YRMember | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Average Annual Return, Percent | 25.02% | ||||||||||||||
| C000016598_0_BBIndexMember_5YRMember | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Average Annual Return, Percent | 14.53% | ||||||||||||||
| C000016598_0_BBIndexMember_10YRMember | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Average Annual Return, Percent | 13.10% | ||||||||||||||
| C000120656_0_BBIndexMember_1YRMember | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Average Annual Return, Percent | 23.81% | ||||||||||||||
| C000120656_0_BBIndexMember_5YRMember | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Average Annual Return, Percent | 13.86% | ||||||||||||||
| C000120656_0_BBIndexMember_10YRMember | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Average Annual Return, Percent | 12.55% | ||||||||||||||
| C000016600_0_BBIndexMember_1YRMember | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Average Annual Return, Percent | 25.02% | ||||||||||||||
| C000016600_0_BBIndexMember_5YRMember | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Average Annual Return, Percent | 14.53% | ||||||||||||||
| C000016600_0_BBIndexMember_10YRMember | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Average Annual Return, Percent | 13.10% | ||||||||||||||
| C000130145_0_BBIndexMember_1YRMember | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Average Annual Return, Percent | 25.02% | ||||||||||||||
| C000130145_0_BBIndexMember_5YRMember | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Average Annual Return, Percent | 14.53% | ||||||||||||||
| C000130145_0_BBIndexMember_10YRMember | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Average Annual Return, Percent | 13.10% | ||||||||||||||
| C000016599_0_BBIndexMember_1YRMember | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Average Annual Return, Percent | 25.02% | ||||||||||||||
| C000016599_0_BBIndexMember_5YRMember | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Average Annual Return, Percent | 14.53% | ||||||||||||||
| C000016599_0_BBIndexMember_10YRMember | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Average Annual Return, Percent | 13.10% | ||||||||||||||
| C000016601_0_BBIndexMember_1YRMember | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Average Annual Return, Percent | 25.02% | ||||||||||||||
| C000016601_0_BBIndexMember_5YRMember | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Average Annual Return, Percent | 14.53% | ||||||||||||||
| C000016601_0_BBIndexMember_10YRMember | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Average Annual Return, Percent | 13.10% | ||||||||||||||
| C000182865_0_BBIndexMember_1YRMember | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Average Annual Return, Percent | 25.02% | ||||||||||||||
| C000182865_0_BBIndexMember_5YRMember | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Average Annual Return, Percent | 14.53% | ||||||||||||||
| C000182865_0_BBIndexMember_LOCMember | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Average Annual Return, Percent | 14.35% | ||||||||||||||
| C000064233_0_BBIndexMember_1YRMember | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Average Annual Return, Percent | 25.02% | ||||||||||||||
| C000064233_0_BBIndexMember_5YRMember | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Average Annual Return, Percent | 14.53% | ||||||||||||||
| C000064233_0_BBIndexMember_10YRMember | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Average Annual Return, Percent | 13.10% | ||||||||||||||
| C000016596_0_BBIndexMember_1YRMember | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Average Annual Return, Percent | 25.02% | ||||||||||||||
| C000016596_0_BBIndexMember_5YRMember | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Average Annual Return, Percent | 14.53% | ||||||||||||||
| C000016596_0_BBIndexMember_10YRMember | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Average Annual Return, Percent | 13.10% | ||||||||||||||
| C000016598_LG_ClassMember_11YRMember | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Line Graph and Table Measure Name | Class C</span>" id="sjs-F86"><span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;">Class C</span> | ||||||||||||||
| C000016598_ClassMember_AsOf_2014Member | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Account Value | $ 10,000 | ||||||||||||||
| C000016598_ClassMember_AsOf_2015Member | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Account Value | $ 10,163 | ||||||||||||||
| C000016598_ClassMember_AsOf_2016Member | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Account Value | $ 10,721 | ||||||||||||||
| C000016598_ClassMember_AsOf_2017Member | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Account Value | $ 13,614 | ||||||||||||||
| C000016598_ClassMember_AsOf_2018Member | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Account Value | $ 12,918 | ||||||||||||||
| C000016598_ClassMember_AsOf_2019Member | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Account Value | $ 16,554 | ||||||||||||||
| C000016598_ClassMember_AsOf_2020Member | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Account Value | $ 20,319 | ||||||||||||||
| C000016598_ClassMember_AsOf_2021Member | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Account Value | $ 25,065 | ||||||||||||||
| C000016598_ClassMember_AsOf_2022Member | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Account Value | $ 18,043 | ||||||||||||||
| C000016598_ClassMember_AsOf_2023Member | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Account Value | $ 24,529 | ||||||||||||||
| C000016598_ClassMember_AsOf_2024Member | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Account Value | $ 33,091 | $ 33,091 | $ 33,091 | $ 33,091 | $ 33,091 | ||||||||||
| C000016598_LG_1_AdditionalIndexMember_11YRMember | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Line Graph and Table Measure Name | S&P 500® Index</span>" id="sjs-F122"><span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;">S&P 500® Index</span> | ||||||||||||||
| C000016598_1_AdditionalIndexMember_AsOf_2014Member | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Account Value | 10,000 | ||||||||||||||
| C000016598_1_AdditionalIndexMember_AsOf_2015Member | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Account Value | 10,138 | ||||||||||||||
| C000016598_1_AdditionalIndexMember_AsOf_2016Member | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Account Value | 11,351 | ||||||||||||||
| C000016598_1_AdditionalIndexMember_AsOf_2017Member | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Account Value | 13,829 | ||||||||||||||
| C000016598_1_AdditionalIndexMember_AsOf_2018Member | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Account Value | 13,223 | ||||||||||||||
| C000016598_1_AdditionalIndexMember_AsOf_2019Member | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Account Value | 17,386 | ||||||||||||||
| C000016598_1_AdditionalIndexMember_AsOf_2020Member | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Account Value | 20,585 | ||||||||||||||
| C000016598_1_AdditionalIndexMember_AsOf_2021Member | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Account Value | 26,494 | ||||||||||||||
| C000016598_1_AdditionalIndexMember_AsOf_2022Member | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Account Value | 21,696 | ||||||||||||||
| C000016598_1_AdditionalIndexMember_AsOf_2023Member | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Account Value | 27,399 | ||||||||||||||
| C000016598_1_AdditionalIndexMember_AsOf_2024Member | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Account Value | $ 34,254 | $ 34,254 | 34,254 | $ 34,254 | $ 34,254 | ||||||||||
| C000016598_ClassMember_1YRMember | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Average Annual Return, Percent | 32.89% | ||||||||||||||
| C000016598_ClassMember_5YRMember | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Average Annual Return, Percent | 14.50% | ||||||||||||||
| C000016598_ClassMember_10YRMember | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Average Annual Return, Percent | 12.71% | ||||||||||||||
| C000016598_NoLoadClassMember_1YRMember | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Average Annual Return, Percent | 33.89% | ||||||||||||||
| C000016598_NoLoadClassMember_5YRMember | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Average Annual Return, Percent | 14.50% | ||||||||||||||
| C000016598_NoLoadClassMember_10YRMember | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Average Annual Return, Percent | 12.71% | ||||||||||||||
| C000120656_LG_ClassMember_11YRMember | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Line Graph and Table Measure Name | Fidelity® Series Opportunistic Insights Fund</span>" id="sjs-F176"><span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;">Fidelity® Series Opportunistic Insights Fund</span> | ||||||||||||||
| C000120656_ClassMember_AsOf_2014Member | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Account Value | 10,000 | ||||||||||||||
| C000120656_ClassMember_AsOf_2015Member | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Account Value | 10,710 | ||||||||||||||
| C000120656_ClassMember_AsOf_2016Member | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Account Value | 10,853 | ||||||||||||||
| C000120656_ClassMember_AsOf_2017Member | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Account Value | 14,430 | ||||||||||||||
| C000120656_ClassMember_AsOf_2018Member | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Account Value | 14,161 | ||||||||||||||
| C000120656_ClassMember_AsOf_2019Member | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Account Value | 18,483 | ||||||||||||||
| C000120656_ClassMember_AsOf_2020Member | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Account Value | 24,246 | ||||||||||||||
| C000120656_ClassMember_AsOf_2021Member | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Account Value | 30,260 | ||||||||||||||
| C000120656_ClassMember_AsOf_2022Member | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Account Value | 22,475 | ||||||||||||||
| C000120656_ClassMember_AsOf_2023Member | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Account Value | 29,936 | ||||||||||||||
| C000120656_ClassMember_AsOf_2024Member | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Account Value | $ 40,819 | $ 40,819 | 40,819 | $ 40,819 | $ 40,819 | ||||||||||
| C000120656_LG_1_AdditionalIndexMember_11YRMember | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Line Graph and Table Measure Name | Russell 3000® Index</span>" id="sjs-F212"><span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;">Russell 3000® Index</span> | ||||||||||||||
| C000120656_1_AdditionalIndexMember_AsOf_2014Member | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Account Value | 10,000 | ||||||||||||||
| C000120656_1_AdditionalIndexMember_AsOf_2015Member | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Account Value | 10,048 | ||||||||||||||
| C000120656_1_AdditionalIndexMember_AsOf_2016Member | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Account Value | 11,327 | ||||||||||||||
| C000120656_1_AdditionalIndexMember_AsOf_2017Member | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Account Value | 13,721 | ||||||||||||||
| C000120656_1_AdditionalIndexMember_AsOf_2018Member | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Account Value | 13,002 | ||||||||||||||
| C000120656_1_AdditionalIndexMember_AsOf_2019Member | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Account Value | 17,035 | ||||||||||||||
| C000120656_1_AdditionalIndexMember_AsOf_2020Member | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Account Value | 20,593 | ||||||||||||||
| C000120656_1_AdditionalIndexMember_AsOf_2021Member | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Account Value | 25,877 | ||||||||||||||
| C000120656_1_AdditionalIndexMember_AsOf_2022Member | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Account Value | 20,907 | ||||||||||||||
| C000120656_1_AdditionalIndexMember_AsOf_2023Member | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Account Value | 26,334 | ||||||||||||||
| C000120656_1_AdditionalIndexMember_AsOf_2024Member | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Account Value | $ 32,604 | $ 32,604 | 32,604 | $ 32,604 | $ 32,604 | ||||||||||
| C000120656_NoLoadClassMember_1YRMember | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Average Annual Return, Percent | 36.35% | ||||||||||||||
| C000120656_NoLoadClassMember_5YRMember | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Average Annual Return, Percent | 17.17% | ||||||||||||||
| C000120656_NoLoadClassMember_10YRMember | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Average Annual Return, Percent | 15.10% | ||||||||||||||
| C000016600_LG_ClassMember_11YRMember | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Line Graph and Table Measure Name | Class I</span>" id="sjs-F257"><span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;">Class I</span> | ||||||||||||||
| C000016600_ClassMember_AsOf_2014Member | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Account Value | 10,000 | ||||||||||||||
| C000016600_ClassMember_AsOf_2015Member | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Account Value | 10,264 | ||||||||||||||
| C000016600_ClassMember_AsOf_2016Member | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Account Value | 10,937 | ||||||||||||||
| C000016600_ClassMember_AsOf_2017Member | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Account Value | 14,032 | ||||||||||||||
| C000016600_ClassMember_AsOf_2018Member | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Account Value | 13,451 | ||||||||||||||
| C000016600_ClassMember_AsOf_2019Member | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Account Value | 17,409 | ||||||||||||||
| C000016600_ClassMember_AsOf_2020Member | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Account Value | 21,581 | ||||||||||||||
| C000016600_ClassMember_AsOf_2021Member | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Account Value | 26,894 | ||||||||||||||
| C000016600_ClassMember_AsOf_2022Member | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Account Value | 19,557 | ||||||||||||||
| C000016600_ClassMember_AsOf_2023Member | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Account Value | 26,648 | ||||||||||||||
| C000016600_ClassMember_AsOf_2024Member | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Account Value | $ 36,033 | $ 36,033 | 36,033 | $ 36,033 | $ 36,033 | ||||||||||
| C000016600_LG_1_AdditionalIndexMember_11YRMember | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Line Graph and Table Measure Name | S&P 500® Index</span>" id="sjs-F293"><span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;">S&P 500® Index</span> | ||||||||||||||
| C000016600_1_AdditionalIndexMember_AsOf_2014Member | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Account Value | 10,000 | ||||||||||||||
| C000016600_1_AdditionalIndexMember_AsOf_2015Member | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Account Value | 10,138 | ||||||||||||||
| C000016600_1_AdditionalIndexMember_AsOf_2016Member | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Account Value | 11,351 | ||||||||||||||
| C000016600_1_AdditionalIndexMember_AsOf_2017Member | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Account Value | 13,829 | ||||||||||||||
| C000016600_1_AdditionalIndexMember_AsOf_2018Member | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Account Value | 13,223 | ||||||||||||||
| C000016600_1_AdditionalIndexMember_AsOf_2019Member | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Account Value | 17,386 | ||||||||||||||
| C000016600_1_AdditionalIndexMember_AsOf_2020Member | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Account Value | 20,585 | ||||||||||||||
| C000016600_1_AdditionalIndexMember_AsOf_2021Member | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Account Value | 26,494 | ||||||||||||||
| C000016600_1_AdditionalIndexMember_AsOf_2022Member | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Account Value | 21,696 | ||||||||||||||
| C000016600_1_AdditionalIndexMember_AsOf_2023Member | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Account Value | 27,399 | ||||||||||||||
| C000016600_1_AdditionalIndexMember_AsOf_2024Member | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Account Value | $ 34,254 | $ 34,254 | 34,254 | $ 34,254 | $ 34,254 | ||||||||||
| C000016600_NoLoadClassMember_1YRMember | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Average Annual Return, Percent | 35.22% | ||||||||||||||
| C000016600_NoLoadClassMember_5YRMember | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Average Annual Return, Percent | 15.66% | ||||||||||||||
| C000016600_NoLoadClassMember_10YRMember | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Average Annual Return, Percent | 13.68% | ||||||||||||||
| C000130145_LG_ClassMember_11YRMember | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Line Graph and Table Measure Name | Class Z</span>" id="sjs-F338"><span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;">Class Z</span> | ||||||||||||||
| C000130145_ClassMember_AsOf_2014Member | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Account Value | 10,000 | ||||||||||||||
| C000130145_ClassMember_AsOf_2015Member | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Account Value | 10,278 | ||||||||||||||
| C000130145_ClassMember_AsOf_2016Member | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Account Value | 10,964 | ||||||||||||||
| C000130145_ClassMember_AsOf_2017Member | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Account Value | 14,088 | ||||||||||||||
| C000130145_ClassMember_AsOf_2018Member | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Account Value | 13,520 | ||||||||||||||
| C000130145_ClassMember_AsOf_2019Member | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Account Value | 17,523 | ||||||||||||||
| C000130145_ClassMember_AsOf_2020Member | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Account Value | 21,744 | ||||||||||||||
| C000130145_ClassMember_AsOf_2021Member | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Account Value | 27,134 | ||||||||||||||
| C000130145_ClassMember_AsOf_2022Member | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Account Value | 19,750 | ||||||||||||||
| C000130145_ClassMember_AsOf_2023Member | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Account Value | 26,945 | ||||||||||||||
| C000130145_ClassMember_AsOf_2024Member | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Account Value | $ 36,483 | $ 36,483 | 36,483 | $ 36,483 | $ 36,483 | ||||||||||
| C000130145_LG_1_AdditionalIndexMember_11YRMember | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Line Graph and Table Measure Name | S&P 500® Index</span>" id="sjs-F374"><span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;">S&P 500® Index</span> | ||||||||||||||
| C000130145_1_AdditionalIndexMember_AsOf_2014Member | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Account Value | 10,000 | ||||||||||||||
| C000130145_1_AdditionalIndexMember_AsOf_2015Member | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Account Value | 10,138 | ||||||||||||||
| C000130145_1_AdditionalIndexMember_AsOf_2016Member | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Account Value | 11,351 | ||||||||||||||
| C000130145_1_AdditionalIndexMember_AsOf_2017Member | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Account Value | 13,829 | ||||||||||||||
| C000130145_1_AdditionalIndexMember_AsOf_2018Member | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Account Value | 13,223 | ||||||||||||||
| C000130145_1_AdditionalIndexMember_AsOf_2019Member | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Account Value | 17,386 | ||||||||||||||
| C000130145_1_AdditionalIndexMember_AsOf_2020Member | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Account Value | 20,585 | ||||||||||||||
| C000130145_1_AdditionalIndexMember_AsOf_2021Member | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Account Value | 26,494 | ||||||||||||||
| C000130145_1_AdditionalIndexMember_AsOf_2022Member | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Account Value | 21,696 | ||||||||||||||
| C000130145_1_AdditionalIndexMember_AsOf_2023Member | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Account Value | 27,399 | ||||||||||||||
| C000130145_1_AdditionalIndexMember_AsOf_2024Member | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Account Value | $ 34,254 | $ 34,254 | 34,254 | $ 34,254 | $ 34,254 | ||||||||||
| C000130145_NoLoadClassMember_1YRMember | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Average Annual Return, Percent | 35.40% | ||||||||||||||
| C000130145_NoLoadClassMember_5YRMember | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Average Annual Return, Percent | 15.80% | ||||||||||||||
| C000130145_NoLoadClassMember_10YRMember | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Average Annual Return, Percent | 13.82% | ||||||||||||||
| C000016599_LG_ClassMember_11YRMember | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Line Graph and Table Measure Name | Class M</span>" id="sjs-F419"><span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;">Class M</span> | ||||||||||||||
| C000016599_ClassMember_AsOf_2014Member | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Account Value | 9,650 | ||||||||||||||
| C000016599_ClassMember_AsOf_2015Member | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Account Value | 9,857 | ||||||||||||||
| C000016599_ClassMember_AsOf_2016Member | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Account Value | 10,449 | ||||||||||||||
| C000016599_ClassMember_AsOf_2017Member | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Account Value | 13,339 | ||||||||||||||
| C000016599_ClassMember_AsOf_2018Member | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Account Value | 12,720 | ||||||||||||||
| C000016599_ClassMember_AsOf_2019Member | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Account Value | 16,383 | ||||||||||||||
| C000016599_ClassMember_AsOf_2020Member | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Account Value | 20,205 | ||||||||||||||
| C000016599_ClassMember_AsOf_2021Member | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Account Value | 25,053 | ||||||||||||||
| C000016599_ClassMember_AsOf_2022Member | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Account Value | 18,128 | ||||||||||||||
| C000016599_ClassMember_AsOf_2023Member | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Account Value | 24,580 | ||||||||||||||
| C000016599_ClassMember_AsOf_2024Member | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Account Value | $ 33,077 | $ 33,077 | 33,077 | $ 33,077 | $ 33,077 | ||||||||||
| C000016599_LG_1_AdditionalIndexMember_11YRMember | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Line Graph and Table Measure Name | S&P 500® Index</span>" id="sjs-F455"><span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;">S&P 500® Index</span> | ||||||||||||||
| C000016599_1_AdditionalIndexMember_AsOf_2014Member | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Account Value | 10,000 | ||||||||||||||
| C000016599_1_AdditionalIndexMember_AsOf_2015Member | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Account Value | 10,138 | ||||||||||||||
| C000016599_1_AdditionalIndexMember_AsOf_2016Member | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Account Value | 11,351 | ||||||||||||||
| C000016599_1_AdditionalIndexMember_AsOf_2017Member | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Account Value | 13,829 | ||||||||||||||
| C000016599_1_AdditionalIndexMember_AsOf_2018Member | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Account Value | 13,223 | ||||||||||||||
| C000016599_1_AdditionalIndexMember_AsOf_2019Member | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Account Value | 17,386 | ||||||||||||||
| C000016599_1_AdditionalIndexMember_AsOf_2020Member | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Account Value | 20,585 | ||||||||||||||
| C000016599_1_AdditionalIndexMember_AsOf_2021Member | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Account Value | 26,494 | ||||||||||||||
| C000016599_1_AdditionalIndexMember_AsOf_2022Member | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Account Value | 21,696 | ||||||||||||||
| C000016599_1_AdditionalIndexMember_AsOf_2023Member | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Account Value | 27,399 | ||||||||||||||
| C000016599_1_AdditionalIndexMember_AsOf_2024Member | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Account Value | $ 34,254 | $ 34,254 | 34,254 | $ 34,254 | $ 34,254 | ||||||||||
| C000016599_ClassMember_1YRMember | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Average Annual Return, Percent | 29.86% | ||||||||||||||
| C000016599_ClassMember_5YRMember | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Average Annual Return, Percent | 14.27% | ||||||||||||||
| C000016599_ClassMember_10YRMember | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Average Annual Return, Percent | 12.71% | ||||||||||||||
| C000016599_NoLoadClassMember_1YRMember | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Average Annual Return, Percent | 34.57% | ||||||||||||||
| C000016599_NoLoadClassMember_5YRMember | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Average Annual Return, Percent | 15.09% | ||||||||||||||
| C000016599_NoLoadClassMember_10YRMember | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Average Annual Return, Percent | 13.11% | ||||||||||||||
| C000016601_LG_ClassMember_11YRMember | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Line Graph and Table Measure Name | Fidelity® Contrafund®</span>" id="sjs-F509"><span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;">Fidelity® Contrafund®</span> | ||||||||||||||
| C000016601_ClassMember_AsOf_2014Member | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Account Value | 10,000 | ||||||||||||||
| C000016601_ClassMember_AsOf_2015Member | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Account Value | 10,646 | ||||||||||||||
| C000016601_ClassMember_AsOf_2016Member | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Account Value | 11,004 | ||||||||||||||
| C000016601_ClassMember_AsOf_2017Member | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Account Value | 14,549 | ||||||||||||||
| C000016601_ClassMember_AsOf_2018Member | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Account Value | 14,239 | ||||||||||||||
| C000016601_ClassMember_AsOf_2019Member | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Account Value | 18,509 | ||||||||||||||
| C000016601_ClassMember_AsOf_2020Member | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Account Value | 24,539 | ||||||||||||||
| C000016601_ClassMember_AsOf_2021Member | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Account Value | 30,517 | ||||||||||||||
| C000016601_ClassMember_AsOf_2022Member | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Account Value | 21,892 | ||||||||||||||
| C000016601_ClassMember_AsOf_2023Member | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Account Value | 30,503 | ||||||||||||||
| C000016601_ClassMember_AsOf_2024Member | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Account Value | $ 41,476 | $ 41,476 | 41,476 | $ 41,476 | $ 41,476 | ||||||||||
| C000016601_LG_1_AdditionalIndexMember_11YRMember | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Line Graph and Table Measure Name | S&P 500® Index</span>" id="sjs-F545"><span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;">S&P 500® Index</span> | ||||||||||||||
| C000016601_1_AdditionalIndexMember_AsOf_2014Member | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Account Value | 10,000 | ||||||||||||||
| C000016601_1_AdditionalIndexMember_AsOf_2015Member | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Account Value | 10,138 | ||||||||||||||
| C000016601_1_AdditionalIndexMember_AsOf_2016Member | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Account Value | 11,351 | ||||||||||||||
| C000016601_1_AdditionalIndexMember_AsOf_2017Member | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Account Value | 13,829 | ||||||||||||||
| C000016601_1_AdditionalIndexMember_AsOf_2018Member | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Account Value | 13,223 | ||||||||||||||
| C000016601_1_AdditionalIndexMember_AsOf_2019Member | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Account Value | 17,386 | ||||||||||||||
| C000016601_1_AdditionalIndexMember_AsOf_2020Member | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Account Value | 20,585 | ||||||||||||||
| C000016601_1_AdditionalIndexMember_AsOf_2021Member | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Account Value | 26,494 | ||||||||||||||
| C000016601_1_AdditionalIndexMember_AsOf_2022Member | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Account Value | 21,696 | ||||||||||||||
| C000016601_1_AdditionalIndexMember_AsOf_2023Member | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Account Value | 27,399 | ||||||||||||||
| C000016601_1_AdditionalIndexMember_AsOf_2024Member | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Account Value | $ 34,254 | $ 34,254 | $ 34,254 | $ 34,254 | $ 34,254 | ||||||||||
| C000016601_NoLoadClassMember_1YRMember | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Average Annual Return, Percent | 35.97% | ||||||||||||||
| C000016601_NoLoadClassMember_5YRMember | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Average Annual Return, Percent | 17.51% | ||||||||||||||
| C000016601_NoLoadClassMember_10YRMember | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Average Annual Return, Percent | 15.29% | ||||||||||||||
| C000182865_LG_ClassMember_8YRMember | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Line Graph and Table Measure Name | Fidelity® Contrafund® K6</span>" id="sjs-D590"><span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;">Fidelity® Contrafund® K6</span> | ||||||||||||||
| C000182865_ClassMember_AsOf_2017Member | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Account Value | 10,000 | ||||||||||||||
| C000182865_ClassMember_AsOf_2018Member | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Account Value | 11,377 | ||||||||||||||
| C000182865_ClassMember_AsOf_2019Member | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Account Value | 11,132 | ||||||||||||||
| C000182865_ClassMember_AsOf_2020Member | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Account Value | 14,584 | ||||||||||||||
| C000182865_ClassMember_AsOf_2021Member | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Account Value | 19,080 | ||||||||||||||
| C000182865_ClassMember_AsOf_2022Member | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Account Value | 23,685 | ||||||||||||||
| C000182865_ClassMember_AsOf_2023Member | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Account Value | 17,262 | ||||||||||||||
| C000182865_ClassMember_AsOf_2024Member | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Account Value | $ 23,764 | $ 23,764 | $ 23,764 | $ 23,764 | 23,764 | ||||||||||
| C000182865_LG_1_AdditionalIndexMember_8YRMember | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Line Graph and Table Measure Name | S&P 500® Index</span>" id="sjs-D617"><span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;">S&P 500® Index</span> | ||||||||||||||
| C000182865_1_AdditionalIndexMember_AsOf_2017Member | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Account Value | 10,000 | ||||||||||||||
| C000182865_1_AdditionalIndexMember_AsOf_2018Member | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Account Value | 11,202 | ||||||||||||||
| C000182865_1_AdditionalIndexMember_AsOf_2019Member | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Account Value | 10,710 | ||||||||||||||
| C000182865_1_AdditionalIndexMember_AsOf_2020Member | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Account Value | 14,083 | ||||||||||||||
| C000182865_1_AdditionalIndexMember_AsOf_2021Member | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Account Value | 16,674 | ||||||||||||||
| C000182865_1_AdditionalIndexMember_AsOf_2022Member | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Account Value | 21,460 | ||||||||||||||
| C000182865_1_AdditionalIndexMember_AsOf_2023Member | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Account Value | 17,574 | ||||||||||||||
| C000182865_1_AdditionalIndexMember_AsOf_2024Member | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Account Value | $ 22,193 | $ 22,193 | $ 22,193 | 22,193 | $ 22,193 | ||||||||||
| C000182865_NoLoadClassMember_1YRMember | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Average Annual Return, Percent | 35.37% | ||||||||||||||
| C000182865_NoLoadClassMember_5YRMember | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Average Annual Return, Percent | 17.14% | ||||||||||||||
| C000182865_NoLoadClassMember_2024-01-01_2024-12-31Member | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Average Annual Return, Percent | 16.60% | ||||||||||||||
| C000064233_LG_ClassMember_11YRMember | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Line Graph and Table Measure Name | Class K</span>" id="sjs-F653"><span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;">Class K</span> | ||||||||||||||
| C000064233_ClassMember_AsOf_2014Member | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Account Value | 10,000 | ||||||||||||||
| C000064233_ClassMember_AsOf_2015Member | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Account Value | 10,655 | ||||||||||||||
| C000064233_ClassMember_AsOf_2016Member | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Account Value | 11,026 | ||||||||||||||
| C000064233_ClassMember_AsOf_2017Member | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Account Value | 14,592 | ||||||||||||||
| C000064233_ClassMember_AsOf_2018Member | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Account Value | 14,290 | ||||||||||||||
| C000064233_ClassMember_AsOf_2019Member | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Account Value | 18,601 | ||||||||||||||
| C000064233_ClassMember_AsOf_2020Member | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Account Value | 24,681 | ||||||||||||||
| C000064233_ClassMember_AsOf_2021Member | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Account Value | 30,709 | ||||||||||||||
| C000064233_ClassMember_AsOf_2022Member | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Account Value | 22,043 | ||||||||||||||
| C000064233_ClassMember_AsOf_2023Member | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Account Value | 30,743 | ||||||||||||||
| C000064233_ClassMember_AsOf_2024Member | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Account Value | $ 41,827 | $ 41,827 | 41,827 | 41,827 | $ 41,827 | ||||||||||
| C000064233_LG_1_AdditionalIndexMember_11YRMember | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Line Graph and Table Measure Name | S&P 500® Index</span>" id="sjs-F689"><span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;">S&P 500® Index</span> | ||||||||||||||
| C000064233_1_AdditionalIndexMember_AsOf_2014Member | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Account Value | 10,000 | ||||||||||||||
| C000064233_1_AdditionalIndexMember_AsOf_2015Member | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Account Value | 10,138 | ||||||||||||||
| C000064233_1_AdditionalIndexMember_AsOf_2016Member | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Account Value | 11,351 | ||||||||||||||
| C000064233_1_AdditionalIndexMember_AsOf_2017Member | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Account Value | 13,829 | ||||||||||||||
| C000064233_1_AdditionalIndexMember_AsOf_2018Member | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Account Value | 13,223 | ||||||||||||||
| C000064233_1_AdditionalIndexMember_AsOf_2019Member | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Account Value | 17,386 | ||||||||||||||
| C000064233_1_AdditionalIndexMember_AsOf_2020Member | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Account Value | 20,585 | ||||||||||||||
| C000064233_1_AdditionalIndexMember_AsOf_2021Member | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Account Value | 26,494 | ||||||||||||||
| C000064233_1_AdditionalIndexMember_AsOf_2022Member | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Account Value | 21,696 | ||||||||||||||
| C000064233_1_AdditionalIndexMember_AsOf_2023Member | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Account Value | 27,399 | ||||||||||||||
| C000064233_1_AdditionalIndexMember_AsOf_2024Member | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Account Value | $ 34,254 | $ 34,254 | 34,254 | $ 34,254 | $ 34,254 | ||||||||||
| C000064233_NoLoadClassMember_1YRMember | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Average Annual Return, Percent | 36.05% | ||||||||||||||
| C000064233_NoLoadClassMember_5YRMember | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Average Annual Return, Percent | 17.59% | ||||||||||||||
| C000064233_NoLoadClassMember_10YRMember | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Average Annual Return, Percent | 15.38% | ||||||||||||||
| C000016596_LG_ClassMember_11YRMember | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Line Graph and Table Measure Name | Class A</span>" id="sjs-F734"><span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;">Class A</span> | ||||||||||||||
| C000016596_ClassMember_AsOf_2014Member | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Account Value | 9,425 | ||||||||||||||
| C000016596_ClassMember_AsOf_2015Member | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Account Value | 9,650 | ||||||||||||||
| C000016596_ClassMember_AsOf_2016Member | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Account Value | 10,258 | ||||||||||||||
| C000016596_ClassMember_AsOf_2017Member | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Account Value | 13,129 | ||||||||||||||
| C000016596_ClassMember_AsOf_2018Member | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Account Value | 12,548 | ||||||||||||||
| C000016596_ClassMember_AsOf_2019Member | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Account Value | 16,206 | ||||||||||||||
| C000016596_ClassMember_AsOf_2020Member | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Account Value | 20,036 | ||||||||||||||
| C000016596_ClassMember_AsOf_2021Member | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Account Value | 24,906 | ||||||||||||||
| C000016596_ClassMember_AsOf_2022Member | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Account Value | 18,062 | ||||||||||||||
| C000016596_ClassMember_AsOf_2023Member | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Account Value | 24,555 | ||||||||||||||
| C000016596_ClassMember_AsOf_2024Member | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Account Value | $ 33,126 | $ 33,126 | 33,126 | $ 33,126 | $ 33,126 | ||||||||||
| C000016596_LG_1_AdditionalIndexMember_11YRMember | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Line Graph and Table Measure Name | S&P 500® Index</span>" id="sjs-F770"><span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;">S&P 500® Index</span> | ||||||||||||||
| C000016596_1_AdditionalIndexMember_AsOf_2014Member | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Account Value | $ 10,000 | ||||||||||||||
| C000016596_1_AdditionalIndexMember_AsOf_2015Member | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Account Value | $ 10,138 | ||||||||||||||
| C000016596_1_AdditionalIndexMember_AsOf_2016Member | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Account Value | $ 11,351 | ||||||||||||||
| C000016596_1_AdditionalIndexMember_AsOf_2017Member | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Account Value | $ 13,829 | ||||||||||||||
| C000016596_1_AdditionalIndexMember_AsOf_2018Member | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Account Value | $ 13,223 | ||||||||||||||
| C000016596_1_AdditionalIndexMember_AsOf_2019Member | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Account Value | $ 17,386 | ||||||||||||||
| C000016596_1_AdditionalIndexMember_AsOf_2020Member | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Account Value | $ 20,585 | ||||||||||||||
| C000016596_1_AdditionalIndexMember_AsOf_2021Member | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Account Value | $ 26,494 | ||||||||||||||
| C000016596_1_AdditionalIndexMember_AsOf_2022Member | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Account Value | $ 21,696 | ||||||||||||||
| C000016596_1_AdditionalIndexMember_AsOf_2023Member | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Account Value | $ 27,399 | ||||||||||||||
| C000016596_1_AdditionalIndexMember_AsOf_2024Member | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Account Value | $ 34,254 | $ 34,254 | $ 34,254 | $ 34,254 | $ 34,254 | ||||||||||
| C000016596_ClassMember_1YRMember | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Average Annual Return, Percent | 27.15% | ||||||||||||||
| C000016596_ClassMember_5YRMember | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Average Annual Return, Percent | 14.01% | ||||||||||||||
| C000016596_ClassMember_10YRMember | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Average Annual Return, Percent | 12.72% | ||||||||||||||
| C000016596_NoLoadClassMember_1YRMember | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Average Annual Return, Percent | 34.91% | ||||||||||||||
| C000016596_NoLoadClassMember_5YRMember | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Average Annual Return, Percent | 15.37% | ||||||||||||||
| C000016596_NoLoadClassMember_10YRMember | |||||||||||||||
| Account Value [Line Items] | |||||||||||||||
| Average Annual Return, Percent | 13.39% |
| Shareholder Report, Holdings (Details) | Dec. 31, 2024 |
| Fidelity Advisor New Insights Fund - Class C | TH0Member | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 11.70% |
| Fidelity Advisor New Insights Fund - Class C | TH1Member | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 8.90% |
| Fidelity Advisor New Insights Fund - Class C | TH2Member | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 6.50% |
| Fidelity Advisor New Insights Fund - Class C | TH3Member | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 6.10% |
| Fidelity Advisor New Insights Fund - Class C | TH4Member | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 5.80% |
| Fidelity Advisor New Insights Fund - Class C | TH5Member | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 5.10% |
| Fidelity Advisor New Insights Fund - Class C | TH6Member | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 2.60% |
| Fidelity Advisor New Insights Fund - Class C | TH7Member | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 2.60% |
| Fidelity Advisor New Insights Fund - Class C | TH8Member | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 2.30% |
| Fidelity Advisor New Insights Fund - Class C | TH9Member | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 2.20% |
| Fidelity Advisor New Insights Fund - Class C | MSFinancialsSectorMember | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 14.80% |
| Fidelity Advisor New Insights Fund - Class C | Information Technology Member | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 26% |
| Fidelity Advisor New Insights Fund - Class C | Healthcare Sector | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 8.30% |
| Fidelity Advisor New Insights Fund - Class C | Real Estate Sector | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 0% |
| Fidelity Advisor New Insights Fund - Class C | Industrial Sector Member | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 12.30% |
| Fidelity Advisor New Insights Fund - Class C | Materials Sector Member | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 1.50% |
| Fidelity Advisor New Insights Fund - Class C | Consumer Discretionary Sector Member | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 11.40% |
| Fidelity Advisor New Insights Fund - Class C | Consumer Staples Sector Member | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 1.20% |
| Fidelity Advisor New Insights Fund - Class C | Communications Sector Member | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 21.40% |
| Fidelity Advisor New Insights Fund - Class C | Energy Sector | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 1.50% |
| Fidelity Advisor New Insights Fund - Class C | Utilities Sector Member | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 1.20% |
| Fidelity Advisor New Insights Fund - Class C | United States | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 92.90% |
| Fidelity Advisor New Insights Fund - Class C | Canada | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 1.90% |
| Fidelity Advisor New Insights Fund - Class C | Taiwan | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 0.70% |
| Fidelity Advisor New Insights Fund - Class C | Netherlands | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 0.60% |
| Fidelity Advisor New Insights Fund - Class C | United Kingdom | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 0.50% |
| Fidelity Advisor New Insights Fund - Class C | China | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 0.40% |
| Fidelity Advisor New Insights Fund - Class C | Italy | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 0.40% |
| Fidelity Advisor New Insights Fund - Class C | CongoDemocraticRepublicOfMember | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 0.40% |
| Fidelity Advisor New Insights Fund - Class C | Korea, Republic of | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 0.40% |
| Fidelity Advisor New Insights Fund - Class C | OtherMember | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 1.80% |
| Fidelity Advisor New Insights Fund - Class C | AACommonStocksMember | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 96.90% |
| Fidelity Advisor New Insights Fund - Class C | AAPreferredStocksMember | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 2.70% |
| Fidelity Advisor New Insights Fund - Class C | AAPreferredSecuritiesMember | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 0% |
| Fidelity Advisor New Insights Fund - Class C | AAShortTermInvestmentsandNetOtherAssetsLiabilitiesMember | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 0.40% |
| Fidelity Series Opportunistic Insights Fund | TH0Member | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 13.20% |
| Fidelity Series Opportunistic Insights Fund | TH1Member | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 9.80% |
| Fidelity Series Opportunistic Insights Fund | TH2Member | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 6.10% |
| Fidelity Series Opportunistic Insights Fund | TH3Member | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 5.70% |
| Fidelity Series Opportunistic Insights Fund | TH4Member | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 4.50% |
| Fidelity Series Opportunistic Insights Fund | TH5Member | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 3% |
| Fidelity Series Opportunistic Insights Fund | TH6Member | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 2.70% |
| Fidelity Series Opportunistic Insights Fund | TH7Member | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 2.30% |
| Fidelity Series Opportunistic Insights Fund | TH8Member | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 2.20% |
| Fidelity Series Opportunistic Insights Fund | TH9Member | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 2.10% |
| Fidelity Series Opportunistic Insights Fund | MSFinancialsSectorMember | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 18% |
| Fidelity Series Opportunistic Insights Fund | Information Technology Member | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 24.60% |
| Fidelity Series Opportunistic Insights Fund | Healthcare Sector | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 9% |
| Fidelity Series Opportunistic Insights Fund | Real Estate Sector | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 0.20% |
| Fidelity Series Opportunistic Insights Fund | Industrial Sector Member | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 10.30% |
| Fidelity Series Opportunistic Insights Fund | Materials Sector Member | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 1.10% |
| Fidelity Series Opportunistic Insights Fund | Consumer Discretionary Sector Member | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 10.10% |
| Fidelity Series Opportunistic Insights Fund | Consumer Staples Sector Member | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 1.40% |
| Fidelity Series Opportunistic Insights Fund | Communications Sector Member | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 21.40% |
| Fidelity Series Opportunistic Insights Fund | Energy Sector | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 1.10% |
| Fidelity Series Opportunistic Insights Fund | Utilities Sector Member | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 0.70% |
| Fidelity Series Opportunistic Insights Fund | United States | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 94.10% |
| Fidelity Series Opportunistic Insights Fund | Canada | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 2.10% |
| Fidelity Series Opportunistic Insights Fund | Taiwan | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 0.40% |
| Fidelity Series Opportunistic Insights Fund | United Kingdom | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 0.30% |
| Fidelity Series Opportunistic Insights Fund | CongoDemocraticRepublicOfMember | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 0.40% |
| Fidelity Series Opportunistic Insights Fund | Korea, Republic of | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 0.30% |
| Fidelity Series Opportunistic Insights Fund | OtherMember | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 1.30% |
| Fidelity Series Opportunistic Insights Fund | Israel | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 0.60% |
| Fidelity Series Opportunistic Insights Fund | Brazil | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 0.30% |
| Fidelity Series Opportunistic Insights Fund | Switzerland | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 0.20% |
| Fidelity Series Opportunistic Insights Fund | AACommonStocksMember | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 96.40% |
| Fidelity Series Opportunistic Insights Fund | AAPreferredStocksMember | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 1.50% |
| Fidelity Series Opportunistic Insights Fund | AAPreferredSecuritiesMember | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 0% |
| Fidelity Series Opportunistic Insights Fund | AAShortTermInvestmentsandNetOtherAssetsLiabilitiesMember | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 2.10% |
| Fidelity Advisor New Insights Fund - Class I | TH0Member | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 11.70% |
| Fidelity Advisor New Insights Fund - Class I | TH1Member | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 8.90% |
| Fidelity Advisor New Insights Fund - Class I | TH2Member | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 6.50% |
| Fidelity Advisor New Insights Fund - Class I | TH3Member | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 6.10% |
| Fidelity Advisor New Insights Fund - Class I | TH4Member | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 5.80% |
| Fidelity Advisor New Insights Fund - Class I | TH5Member | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 5.10% |
| Fidelity Advisor New Insights Fund - Class I | TH6Member | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 2.60% |
| Fidelity Advisor New Insights Fund - Class I | TH7Member | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 2.60% |
| Fidelity Advisor New Insights Fund - Class I | TH8Member | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 2.30% |
| Fidelity Advisor New Insights Fund - Class I | TH9Member | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 2.20% |
| Fidelity Advisor New Insights Fund - Class I | MSFinancialsSectorMember | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 14.80% |
| Fidelity Advisor New Insights Fund - Class I | Information Technology Member | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 26% |
| Fidelity Advisor New Insights Fund - Class I | Healthcare Sector | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 8.30% |
| Fidelity Advisor New Insights Fund - Class I | Real Estate Sector | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 0% |
| Fidelity Advisor New Insights Fund - Class I | Industrial Sector Member | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 12.30% |
| Fidelity Advisor New Insights Fund - Class I | Materials Sector Member | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 1.50% |
| Fidelity Advisor New Insights Fund - Class I | Consumer Discretionary Sector Member | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 11.40% |
| Fidelity Advisor New Insights Fund - Class I | Consumer Staples Sector Member | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 1.20% |
| Fidelity Advisor New Insights Fund - Class I | Communications Sector Member | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 21.40% |
| Fidelity Advisor New Insights Fund - Class I | Energy Sector | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 1.50% |
| Fidelity Advisor New Insights Fund - Class I | Utilities Sector Member | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 1.20% |
| Fidelity Advisor New Insights Fund - Class I | United States | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 92.90% |
| Fidelity Advisor New Insights Fund - Class I | Canada | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 1.90% |
| Fidelity Advisor New Insights Fund - Class I | Taiwan | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 0.70% |
| Fidelity Advisor New Insights Fund - Class I | Netherlands | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 0.60% |
| Fidelity Advisor New Insights Fund - Class I | United Kingdom | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 0.50% |
| Fidelity Advisor New Insights Fund - Class I | China | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 0.40% |
| Fidelity Advisor New Insights Fund - Class I | Italy | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 0.40% |
| Fidelity Advisor New Insights Fund - Class I | CongoDemocraticRepublicOfMember | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 0.40% |
| Fidelity Advisor New Insights Fund - Class I | Korea, Republic of | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 0.40% |
| Fidelity Advisor New Insights Fund - Class I | OtherMember | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 1.80% |
| Fidelity Advisor New Insights Fund - Class I | AACommonStocksMember | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 96.90% |
| Fidelity Advisor New Insights Fund - Class I | AAPreferredStocksMember | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 2.70% |
| Fidelity Advisor New Insights Fund - Class I | AAPreferredSecuritiesMember | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 0% |
| Fidelity Advisor New Insights Fund - Class I | AAShortTermInvestmentsandNetOtherAssetsLiabilitiesMember | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 0.40% |
| Fidelity Advisor New Insights Fund - Class Z | TH0Member | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 11.70% |
| Fidelity Advisor New Insights Fund - Class Z | TH1Member | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 8.90% |
| Fidelity Advisor New Insights Fund - Class Z | TH2Member | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 6.50% |
| Fidelity Advisor New Insights Fund - Class Z | TH3Member | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 6.10% |
| Fidelity Advisor New Insights Fund - Class Z | TH4Member | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 5.80% |
| Fidelity Advisor New Insights Fund - Class Z | TH5Member | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 5.10% |
| Fidelity Advisor New Insights Fund - Class Z | TH6Member | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 2.60% |
| Fidelity Advisor New Insights Fund - Class Z | TH7Member | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 2.60% |
| Fidelity Advisor New Insights Fund - Class Z | TH8Member | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 2.30% |
| Fidelity Advisor New Insights Fund - Class Z | TH9Member | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 2.20% |
| Fidelity Advisor New Insights Fund - Class Z | MSFinancialsSectorMember | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 14.80% |
| Fidelity Advisor New Insights Fund - Class Z | Information Technology Member | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 26% |
| Fidelity Advisor New Insights Fund - Class Z | Healthcare Sector | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 8.30% |
| Fidelity Advisor New Insights Fund - Class Z | Real Estate Sector | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 0% |
| Fidelity Advisor New Insights Fund - Class Z | Industrial Sector Member | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 12.30% |
| Fidelity Advisor New Insights Fund - Class Z | Materials Sector Member | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 1.50% |
| Fidelity Advisor New Insights Fund - Class Z | Consumer Discretionary Sector Member | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 11.40% |
| Fidelity Advisor New Insights Fund - Class Z | Consumer Staples Sector Member | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 1.20% |
| Fidelity Advisor New Insights Fund - Class Z | Communications Sector Member | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 21.40% |
| Fidelity Advisor New Insights Fund - Class Z | Energy Sector | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 1.50% |
| Fidelity Advisor New Insights Fund - Class Z | Utilities Sector Member | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 1.20% |
| Fidelity Advisor New Insights Fund - Class Z | United States | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 92.90% |
| Fidelity Advisor New Insights Fund - Class Z | Canada | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 1.90% |
| Fidelity Advisor New Insights Fund - Class Z | Taiwan | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 0.70% |
| Fidelity Advisor New Insights Fund - Class Z | Netherlands | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 0.60% |
| Fidelity Advisor New Insights Fund - Class Z | United Kingdom | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 0.50% |
| Fidelity Advisor New Insights Fund - Class Z | China | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 0.40% |
| Fidelity Advisor New Insights Fund - Class Z | Italy | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 0.40% |
| Fidelity Advisor New Insights Fund - Class Z | CongoDemocraticRepublicOfMember | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 0.40% |
| Fidelity Advisor New Insights Fund - Class Z | Korea, Republic of | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 0.40% |
| Fidelity Advisor New Insights Fund - Class Z | OtherMember | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 1.80% |
| Fidelity Advisor New Insights Fund - Class Z | AACommonStocksMember | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 96.90% |
| Fidelity Advisor New Insights Fund - Class Z | AAPreferredStocksMember | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 2.70% |
| Fidelity Advisor New Insights Fund - Class Z | AAPreferredSecuritiesMember | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 0% |
| Fidelity Advisor New Insights Fund - Class Z | AAShortTermInvestmentsandNetOtherAssetsLiabilitiesMember | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 0.40% |
| Fidelity Advisor New Insights Fund - Class M | TH0Member | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 11.70% |
| Fidelity Advisor New Insights Fund - Class M | TH1Member | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 8.90% |
| Fidelity Advisor New Insights Fund - Class M | TH2Member | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 6.50% |
| Fidelity Advisor New Insights Fund - Class M | TH3Member | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 6.10% |
| Fidelity Advisor New Insights Fund - Class M | TH4Member | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 5.80% |
| Fidelity Advisor New Insights Fund - Class M | TH5Member | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 5.10% |
| Fidelity Advisor New Insights Fund - Class M | TH6Member | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 2.60% |
| Fidelity Advisor New Insights Fund - Class M | TH7Member | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 2.60% |
| Fidelity Advisor New Insights Fund - Class M | TH8Member | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 2.30% |
| Fidelity Advisor New Insights Fund - Class M | TH9Member | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 2.20% |
| Fidelity Advisor New Insights Fund - Class M | MSFinancialsSectorMember | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 14.80% |
| Fidelity Advisor New Insights Fund - Class M | Information Technology Member | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 26% |
| Fidelity Advisor New Insights Fund - Class M | Healthcare Sector | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 8.30% |
| Fidelity Advisor New Insights Fund - Class M | Real Estate Sector | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 0% |
| Fidelity Advisor New Insights Fund - Class M | Industrial Sector Member | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 12.30% |
| Fidelity Advisor New Insights Fund - Class M | Materials Sector Member | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 1.50% |
| Fidelity Advisor New Insights Fund - Class M | Consumer Discretionary Sector Member | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 11.40% |
| Fidelity Advisor New Insights Fund - Class M | Consumer Staples Sector Member | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 1.20% |
| Fidelity Advisor New Insights Fund - Class M | Communications Sector Member | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 21.40% |
| Fidelity Advisor New Insights Fund - Class M | Energy Sector | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 1.50% |
| Fidelity Advisor New Insights Fund - Class M | Utilities Sector Member | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 1.20% |
| Fidelity Advisor New Insights Fund - Class M | United States | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 92.90% |
| Fidelity Advisor New Insights Fund - Class M | Canada | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 1.90% |
| Fidelity Advisor New Insights Fund - Class M | Taiwan | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 0.70% |
| Fidelity Advisor New Insights Fund - Class M | Netherlands | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 0.60% |
| Fidelity Advisor New Insights Fund - Class M | United Kingdom | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 0.50% |
| Fidelity Advisor New Insights Fund - Class M | China | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 0.40% |
| Fidelity Advisor New Insights Fund - Class M | Italy | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 0.40% |
| Fidelity Advisor New Insights Fund - Class M | CongoDemocraticRepublicOfMember | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 0.40% |
| Fidelity Advisor New Insights Fund - Class M | Korea, Republic of | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 0.40% |
| Fidelity Advisor New Insights Fund - Class M | OtherMember | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 1.80% |
| Fidelity Advisor New Insights Fund - Class M | AACommonStocksMember | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 96.90% |
| Fidelity Advisor New Insights Fund - Class M | AAPreferredStocksMember | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 2.70% |
| Fidelity Advisor New Insights Fund - Class M | AAPreferredSecuritiesMember | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 0% |
| Fidelity Advisor New Insights Fund - Class M | AAShortTermInvestmentsandNetOtherAssetsLiabilitiesMember | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 0.40% |
| Fidelity Contrafund | TH0Member | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 15.80% |
| Fidelity Contrafund | TH1Member | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 8.50% |
| Fidelity Contrafund | TH2Member | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 8.40% |
| Fidelity Contrafund | TH3Member | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 6.80% |
| Fidelity Contrafund | TH4Member | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 5.40% |
| Fidelity Contrafund | TH5Member | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 3.40% |
| Fidelity Contrafund | TH6Member | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 2.60% |
| Fidelity Contrafund | TH7Member | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 2.50% |
| Fidelity Contrafund | TH8Member | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 2.40% |
| Fidelity Contrafund | TH9Member | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 2% |
| Fidelity Contrafund | MSFinancialsSectorMember | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 18% |
| Fidelity Contrafund | Information Technology Member | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 24.40% |
| Fidelity Contrafund | Healthcare Sector | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 8.70% |
| Fidelity Contrafund | Real Estate Sector | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 0.10% |
| Fidelity Contrafund | Industrial Sector Member | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 7.90% |
| Fidelity Contrafund | Materials Sector Member | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 1% |
| Fidelity Contrafund | Consumer Discretionary Sector Member | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 10.80% |
| Fidelity Contrafund | Consumer Staples Sector Member | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 1.70% |
| Fidelity Contrafund | Communications Sector Member | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 23.60% |
| Fidelity Contrafund | Energy Sector | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 1.20% |
| Fidelity Contrafund | Utilities Sector Member | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 0.70% |
| Fidelity Contrafund | United States | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 94.60% |
| Fidelity Contrafund | Canada | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 1.70% |
| Fidelity Contrafund | Taiwan | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 0.40% |
| Fidelity Contrafund | Netherlands | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 0.30% |
| Fidelity Contrafund | United Kingdom | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 0.30% |
| Fidelity Contrafund | CongoDemocraticRepublicOfMember | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 0.50% |
| Fidelity Contrafund | OtherMember | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 1.20% |
| Fidelity Contrafund | Israel | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 0.30% |
| Fidelity Contrafund | Brazil | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 0.30% |
| Fidelity Contrafund | Switzerland | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 0.40% |
| Fidelity Contrafund | AACommonStocksMember | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 96.30% |
| Fidelity Contrafund | AAPreferredStocksMember | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 1.80% |
| Fidelity Contrafund | AAPreferredSecuritiesMember | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 0% |
| Fidelity Contrafund | AAShortTermInvestmentsandNetOtherAssetsLiabilitiesMember | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 1.90% |
| Fidelity Contrafund K6 | TH0Member | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 14.90% |
| Fidelity Contrafund K6 | TH1Member | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 9.50% |
| Fidelity Contrafund K6 | TH2Member | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 7.70% |
| Fidelity Contrafund K6 | TH3Member | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 6% |
| Fidelity Contrafund K6 | TH4Member | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 5.60% |
| Fidelity Contrafund K6 | TH5Member | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 3.50% |
| Fidelity Contrafund K6 | TH6Member | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 2.70% |
| Fidelity Contrafund K6 | TH7Member | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 2.50% |
| Fidelity Contrafund K6 | TH8Member | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 2.50% |
| Fidelity Contrafund K6 | TH9Member | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 2% |
| Fidelity Contrafund K6 | MSFinancialsSectorMember | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 17.80% |
| Fidelity Contrafund K6 | Information Technology Member | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 26.20% |
| Fidelity Contrafund K6 | Healthcare Sector | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 9.20% |
| Fidelity Contrafund K6 | Real Estate Sector | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 0.10% |
| Fidelity Contrafund K6 | Industrial Sector Member | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 7.50% |
| Fidelity Contrafund K6 | Materials Sector Member | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 1.10% |
| Fidelity Contrafund K6 | Consumer Discretionary Sector Member | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 10.30% |
| Fidelity Contrafund K6 | Consumer Staples Sector Member | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 1.80% |
| Fidelity Contrafund K6 | Communications Sector Member | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 22.80% |
| Fidelity Contrafund K6 | Energy Sector | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 1.30% |
| Fidelity Contrafund K6 | Utilities Sector Member | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 0.80% |
| Fidelity Contrafund K6 | United States | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 94.40% |
| Fidelity Contrafund K6 | Canada | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 1.90% |
| Fidelity Contrafund K6 | Taiwan | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 0.40% |
| Fidelity Contrafund K6 | Netherlands | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 0.30% |
| Fidelity Contrafund K6 | United Kingdom | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 0.30% |
| Fidelity Contrafund K6 | CongoDemocraticRepublicOfMember | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 0.50% |
| Fidelity Contrafund K6 | OtherMember | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 1.30% |
| Fidelity Contrafund K6 | Israel | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 0.30% |
| Fidelity Contrafund K6 | Brazil | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 0.30% |
| Fidelity Contrafund K6 | Switzerland | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 0.30% |
| Fidelity Contrafund K6 | AACommonStocksMember | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 97.80% |
| Fidelity Contrafund K6 | AAPreferredStocksMember | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 1.10% |
| Fidelity Contrafund K6 | AAPreferredSecuritiesMember | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 0% |
| Fidelity Contrafund K6 | AAShortTermInvestmentsandNetOtherAssetsLiabilitiesMember | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 1.10% |
| Fidelity Contrafund - Class K | TH0Member | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 15.80% |
| Fidelity Contrafund - Class K | TH1Member | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 8.50% |
| Fidelity Contrafund - Class K | TH2Member | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 8.40% |
| Fidelity Contrafund - Class K | TH3Member | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 6.80% |
| Fidelity Contrafund - Class K | TH4Member | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 5.40% |
| Fidelity Contrafund - Class K | TH5Member | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 3.40% |
| Fidelity Contrafund - Class K | TH6Member | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 2.60% |
| Fidelity Contrafund - Class K | TH7Member | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 2.50% |
| Fidelity Contrafund - Class K | TH8Member | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 2.40% |
| Fidelity Contrafund - Class K | TH9Member | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 2% |
| Fidelity Contrafund - Class K | MSFinancialsSectorMember | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 18% |
| Fidelity Contrafund - Class K | Information Technology Member | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 24.40% |
| Fidelity Contrafund - Class K | Healthcare Sector | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 8.70% |
| Fidelity Contrafund - Class K | Real Estate Sector | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 0.10% |
| Fidelity Contrafund - Class K | Industrial Sector Member | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 7.90% |
| Fidelity Contrafund - Class K | Materials Sector Member | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 1% |
| Fidelity Contrafund - Class K | Consumer Discretionary Sector Member | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 10.80% |
| Fidelity Contrafund - Class K | Consumer Staples Sector Member | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 1.70% |
| Fidelity Contrafund - Class K | Communications Sector Member | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 23.60% |
| Fidelity Contrafund - Class K | Energy Sector | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 1.20% |
| Fidelity Contrafund - Class K | Utilities Sector Member | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 0.70% |
| Fidelity Contrafund - Class K | United States | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 94.60% |
| Fidelity Contrafund - Class K | Canada | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 1.70% |
| Fidelity Contrafund - Class K | Taiwan | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 0.40% |
| Fidelity Contrafund - Class K | Netherlands | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 0.30% |
| Fidelity Contrafund - Class K | United Kingdom | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 0.30% |
| Fidelity Contrafund - Class K | CongoDemocraticRepublicOfMember | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 0.50% |
| Fidelity Contrafund - Class K | OtherMember | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 1.20% |
| Fidelity Contrafund - Class K | Israel | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 0.30% |
| Fidelity Contrafund - Class K | Brazil | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 0.30% |
| Fidelity Contrafund - Class K | Switzerland | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 0.40% |
| Fidelity Contrafund - Class K | AACommonStocksMember | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 96.30% |
| Fidelity Contrafund - Class K | AAPreferredStocksMember | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 1.80% |
| Fidelity Contrafund - Class K | AAPreferredSecuritiesMember | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 0% |
| Fidelity Contrafund - Class K | AAShortTermInvestmentsandNetOtherAssetsLiabilitiesMember | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 1.90% |
| Fidelity Advisor New Insights Fund - Class A | TH0Member | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 11.70% |
| Fidelity Advisor New Insights Fund - Class A | TH1Member | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 8.90% |
| Fidelity Advisor New Insights Fund - Class A | TH2Member | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 6.50% |
| Fidelity Advisor New Insights Fund - Class A | TH3Member | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 6.10% |
| Fidelity Advisor New Insights Fund - Class A | TH4Member | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 5.80% |
| Fidelity Advisor New Insights Fund - Class A | TH5Member | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 5.10% |
| Fidelity Advisor New Insights Fund - Class A | TH6Member | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 2.60% |
| Fidelity Advisor New Insights Fund - Class A | TH7Member | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 2.60% |
| Fidelity Advisor New Insights Fund - Class A | TH8Member | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 2.30% |
| Fidelity Advisor New Insights Fund - Class A | TH9Member | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 2.20% |
| Fidelity Advisor New Insights Fund - Class A | MSFinancialsSectorMember | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 14.80% |
| Fidelity Advisor New Insights Fund - Class A | Information Technology Member | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 26% |
| Fidelity Advisor New Insights Fund - Class A | Healthcare Sector | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 8.30% |
| Fidelity Advisor New Insights Fund - Class A | Real Estate Sector | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 0% |
| Fidelity Advisor New Insights Fund - Class A | Industrial Sector Member | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 12.30% |
| Fidelity Advisor New Insights Fund - Class A | Materials Sector Member | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 1.50% |
| Fidelity Advisor New Insights Fund - Class A | Consumer Discretionary Sector Member | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 11.40% |
| Fidelity Advisor New Insights Fund - Class A | Consumer Staples Sector Member | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 1.20% |
| Fidelity Advisor New Insights Fund - Class A | Communications Sector Member | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 21.40% |
| Fidelity Advisor New Insights Fund - Class A | Energy Sector | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 1.50% |
| Fidelity Advisor New Insights Fund - Class A | Utilities Sector Member | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 1.20% |
| Fidelity Advisor New Insights Fund - Class A | United States | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 92.90% |
| Fidelity Advisor New Insights Fund - Class A | Canada | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 1.90% |
| Fidelity Advisor New Insights Fund - Class A | Taiwan | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 0.70% |
| Fidelity Advisor New Insights Fund - Class A | Netherlands | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 0.60% |
| Fidelity Advisor New Insights Fund - Class A | United Kingdom | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 0.50% |
| Fidelity Advisor New Insights Fund - Class A | China | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 0.40% |
| Fidelity Advisor New Insights Fund - Class A | Italy | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 0.40% |
| Fidelity Advisor New Insights Fund - Class A | CongoDemocraticRepublicOfMember | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 0.40% |
| Fidelity Advisor New Insights Fund - Class A | Korea, Republic of | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 0.40% |
| Fidelity Advisor New Insights Fund - Class A | OtherMember | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 1.80% |
| Fidelity Advisor New Insights Fund - Class A | AACommonStocksMember | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 96.90% |
| Fidelity Advisor New Insights Fund - Class A | AAPreferredStocksMember | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 2.70% |
| Fidelity Advisor New Insights Fund - Class A | AAPreferredSecuritiesMember | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 0% |
| Fidelity Advisor New Insights Fund - Class A | AAShortTermInvestmentsandNetOtherAssetsLiabilitiesMember | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 0.40% |
