| Form N-CSR Cover | 6 Months Ended |
| May 31, 2024 | |
| Shareholder Report [Line Items] | |
| Document Type | N-CSRS/A |
| Amendment Flag | true |
| Registrant Name | BNY Mellon New York AMT-Free Municipal Bond Fund |
| Entity Central Index Key | 0000797920 |
| Document Period End Date | May 31, 2024 |
| Shareholder Report | 6 Months Ended | |
| May 31, 2024 USD ($) | ||
| Shareholder Report [Line Items] | ||
| Document Type | N-CSRS/A | |
| Amendment Flag | true | |
| Registrant Name | BNY Mellon New York AMT-Free Municipal Bond Fund | |
| Entity Central Index Key | 0000797920 | |
| Document Period End Date | May 31, 2024 | |
| Class A – PSNYX | ||
| Shareholder Report [Line Items] | ||
| Fund Name | BNY Mellon New York AMT-Free Municipal Bond Fund | |
| Class Name | Class A | |
| Trading Symbol | PSNYX | |
| Shareholder Report Annual or Semi-Annual | semi-annual shareholder report | |
| Class C– PNYCX | ||
| Shareholder Report [Line Items] | ||
| Fund Name | BNY Mellon New York AMT-Free Municipal Bond Fund | |
| Class Name | Class C | |
| Trading Symbol | PNYCX | |
| Shareholder Report Annual or Semi-Annual | semi-annual shareholder report | |
| Class I – DNYIX | ||
| Shareholder Report [Line Items] | ||
| Fund Name | BNY Mellon New York AMT-Free Municipal Bond Fund | |
| Class Name | Class I | |
| Trading Symbol | DNYIX | |
| Shareholder Report Annual or Semi-Annual | semi-annual shareholder report | |
| Class Y – DNYYX | ||
| Shareholder Report [Line Items] | ||
| Fund Name | BNY Mellon New York AMT-Free Municipal Bond Fund | |
| Class Name | Class Y | |
| Trading Symbol | DNYYX | |
| Shareholder Report Annual or Semi-Annual | semi-annual shareholder report | |
| Class Z – DNYAX | ||
| Shareholder Report [Line Items] | ||
| Fund Name | BNY Mellon New York AMT-Free Municipal Bond Fund | |
| Class Name | Class Z | |
| Trading Symbol | DNYAX | |
| Shareholder Report Annual or Semi-Annual | semi-annual shareholder report | |
| BNY Mellon New York AMT-Free Municipal Bond Fund | Class A – PSNYX | ||
| Shareholder Report [Line Items] | ||
| Annual or Semi-Annual Statement [Text Block] | This semi-annual shareholder report contains important information about BNY Mellon New York AMT-Free Municipal Bond Fund (the “Fund”) for the period of December 1, 2023 to May 31, 2024. You can find additional information about the Fund at im.bnymellon.com/literaturecenter. You can also request this information by calling 1-800-373-9387 (inside the U.S. only) or by sending an e-mail request to info bnymellon.com. | |
| Additional Information [Text Block] | You can find additional information about the Fund at im.bnymellon.com/literaturecenter. You can also request this information by calling 1-800-373-9387 (inside the U.S. only) or by sending an e-mail request to info@bnymellon.com. | |
| Additional Information Phone Number | 1-800-373-9387 | |
| Additional Information Email | info@bnymellon.com | |
| Additional Information Website | im.bnymellon.com/literaturecenter | |
| Expenses [Text Block] | What were the Fund’s costs for the last six months? (based on a hypothetical $10,000 investment) Share Class Costs of a $10,000 investment Costs paid as a percentage of a $10,000 investment Class A * $41 0.81% ** * During the period, fees were waived and/or expenses reimbursed pursuant to an agreement with the Fund’s investment adviser, BNY Mellon Investment Adviser, Inc. If this agreement is not extended in the future, expenses could be higher. ** Annualized | |
| Expenses Paid, Amount | $ 41 | [1] |
| Expense Ratio, Percent | 0.81% | [1],[2] |
| Net Assets | $ 924,000,000 | |
| Holdings Count | 221 | |
| Portfolio Turnover | 8.16% | |
| Additional Fund Statistics [Text Block] | KEY FUND STATISTICS (AS OF 5/31/24) Fund Size (Millions) Number of Holdings Portfolio Turnover $924 221 8.16% | |
| Holdings [Text Block] | Portfolio Holdings (as of 5/31/24) Sector Allocation (Based on Net Assets) | |
| Updated Prospectus Web Address | im.bnymellon.com/literaturecenter | |
| BNY Mellon New York AMT-Free Municipal Bond Fund | Class C– PNYCX | ||
| Shareholder Report [Line Items] | ||
| Annual or Semi-Annual Statement [Text Block] | This semi-annual shareholder report contains important information about BNY Mellon New York AMT-Free Municipal Bond Fund (the “Fund”) for the period of December 1, 2023 to May 31, 2024. You can find additional information about the Fund at im.bnymellon.com/literaturecenter. You can also request this information by calling 1-800-373-9387 (inside the U.S. only) or by sending an e-mail request to info bnymellon.com. | |
| Additional Information [Text Block] | You can find additional information about the Fund at im.bnymellon.com/literaturecenter. You can also request this information by calling 1-800-373-9387 (inside the U.S. only) or by sending an e-mail request to info@bnymellon.com. | |
| Additional Information Phone Number | 1-800-373-9387 | |
| Additional Information Email | info@bnymellon.com | |
| Additional Information Website | im.bnymellon.com/literaturecenter | |
| Expenses [Text Block] | What were the Fund’s costs for the last six months? (based on a hypothetical $10,000 investment) Share Class Costs of a $10,000 investment Costs paid as a percentage of a $10,000 investment Class C * $79 1.58% ** * During the period, fees were waived and/or expenses reimbursed pursuant to an agreement with the Fund’s investment adviser, BNY Mellon Investment Adviser, Inc. If this agreement is not extended in the future, expenses could be higher. ** Annualized | |
| Expenses Paid, Amount | $ 79 | [3] |
| Expense Ratio, Percent | 1.58% | [3],[4] |
| Net Assets | $ 924,000,000 | |
| Holdings Count | 221 | |
| Portfolio Turnover | 8.16% | |
| Additional Fund Statistics [Text Block] | KEY FUND STATISTICS (AS OF 5/31/24) Fund Size (Millions) Number of Holdings Portfolio Turnover $924 221 8.16% | |
| Holdings [Text Block] | Portfolio Holdings (as of 5/31/24) Sector Allocation (Based on Net Assets) | |
| Updated Prospectus Web Address | im.bnymellon.com/literaturecenter | |
| BNY Mellon New York AMT-Free Municipal Bond Fund | Class I – DNYIX | ||
| Shareholder Report [Line Items] | ||
| Annual or Semi-Annual Statement [Text Block] | This semi-annual shareholder report contains important information about BNY Mellon New York AMT-Free Municipal Bond Fund (the “Fund”) for the period of December 1, 2023 to May 31, 2024. You can find additional information about the Fund at im.bnymellon.com/literaturecenter. You can also request this information by calling 1-800-373-9387 (inside the U.S. only) or by sending an e-mail request to info bnymellon.com. | |
| Additional Information [Text Block] | You can find additional information about the Fund at im.bnymellon.com/literaturecenter. You can also request this information by calling 1-800-373-9387 (inside the U.S. only) or by sending an e-mail request to info@bnymellon.com. | |
| Additional Information Phone Number | 1-800-373-9387 | |
| Additional Information Email | info@bnymellon.com | |
| Additional Information Website | im.bnymellon.com/literaturecenter | |
| Expenses [Text Block] | What were the Fund’s costs for the last six months? (based on a hypothetical $10,000 investment) Share Class Costs of a $10,000 investment Costs paid as a percentage of a $10,000 investment Class I * $28 0.56% ** * During the period, fees were waived and/or expenses reimbursed pursuant to an agreement with the Fund’s investment adviser, BNY Mellon Investment Adviser, Inc. If this agreement is not extended in the future, expenses could be higher. ** Annualized | |
| Expenses Paid, Amount | $ 28 | [5] |
| Expense Ratio, Percent | 0.56% | [5],[6] |
| Net Assets | $ 924,000,000 | |
| Holdings Count | 221 | |
| Portfolio Turnover | 8.16% | |
| Additional Fund Statistics [Text Block] | KEY FUND STATISTICS (AS OF 5/31/24) Fund Size (Millions) Number of Holdings Portfolio Turnover $924 221 8.16% | |
| Holdings [Text Block] | Portfolio Holdings (as of 5/31/24) Sector Allocation (Based on Net Assets) | |
| Updated Prospectus Web Address | im.bnymellon.com/literaturecenter | |
| BNY Mellon New York AMT-Free Municipal Bond Fund | Class Y – DNYYX | ||
| Shareholder Report [Line Items] | ||
| Annual or Semi-Annual Statement [Text Block] | This semi-annual shareholder report contains important information about BNY Mellon New York AMT-Free Municipal Bond Fund (the “Fund”) for the period of December 1, 2023 to May 31, 2024. You can find additional information about the Fund at im.bnymellon.com/literaturecenter. You can also request this information by calling 1-800-373-9387 (inside the U.S. only) or by sending an e-mail request to info bnymellon.com. | |
| Additional Information [Text Block] | You can find additional information about the Fund at im.bnymellon.com/literaturecenter. You can also request this information by calling 1-800-373-9387 (inside the U.S. only) or by sending an e-mail request to info@bnymellon.com. | |
| Additional Information Phone Number | 1-800-373-9387 | |
| Additional Information Email | info@bnymellon.com | |
| Additional Information Website | im.bnymellon.com/literaturecenter | |
| Expenses [Text Block] | What were the Fund’s costs for the last six months? (based on a hypothetical $10,000 investment) Share Class Costs of a $10,000 investment Costs paid as a percentage of a $10,000 investment Class Y $28 0.56% * * Annualized | |
| Expenses Paid, Amount | $ 28 | |
| Expense Ratio, Percent | 0.56% | [7] |
| Net Assets | $ 924,000,000 | |
| Holdings Count | 221 | |
| Portfolio Turnover | 8.16% | |
| Additional Fund Statistics [Text Block] | KEY FUND STATISTICS (AS OF 5/31/24) Fund Size (Millions) Number of Holdings Portfolio Turnover $924 221 8.16% | |
| Holdings [Text Block] | Portfolio Holdings (as of 5/31/24) Sector Allocation (Based on Net Assets) | |
| Updated Prospectus Web Address | im.bnymellon.com/literaturecenter | |
| BNY Mellon New York AMT-Free Municipal Bond Fund | Class Z – DNYAX | ||
| Shareholder Report [Line Items] | ||
| Annual or Semi-Annual Statement [Text Block] | This semi-annual shareholder report contains important information about BNY Mellon New York AMT-Free Municipal Bond Fund (the “Fund”) for the period of May 17, 2024, the commencement of the Fund’s Class Z shares, to May 31, 2024. You can find additional information about the Fund at im.bnymellon.com/literaturecenter. You can also request this information by calling 1-800-373-9387 (inside the U.S. only) or by sending an e-mail request to info bnymellon.com. | |
| Additional Information [Text Block] | You can find additional information about the Fund at im.bnymellon.com/literaturecenter. You can also request this information by calling 1-800-373-9387 (inside the U.S. only) or by sending an e-mail request to info@bnymellon.com. | |
| Material Fund Change Notice [Text Block] | This report describes changes to the Fund that occurred during the reporting period. | |
| Additional Information Phone Number | 1-800-373-9387 | |
| Additional Information Email | info@bnymellon.com | |
| Additional Information Website | im.bnymellon.com/literaturecenter | |
| Expenses [Text Block] | What were the Fund’s costs for the period? (based on a hypothetical $10,000 investment) Share Class Costs of a $10,000 investment Costs paid as a percentage of a $10,000 investment Class Z * $3 0.71% ** * During the period, fees were waived and/or expenses reimbursed pursuant to an agreement with the Fund’s investment adviser, BNY Mellon Investment Adviser, Inc. If this agreement is not extended in the future, expenses could be higher. ** Annualized | |
| Expenses Paid, Amount | $ 3 | [8] |
| Expense Ratio, Percent | 0.71% | [8],[9] |
| Net Assets | $ 924,000,000 | |
| Holdings Count | 221 | |
| Portfolio Turnover | 8.16% | |
| Additional Fund Statistics [Text Block] | KEY FUND STATISTICS (AS OF 5/31/24) Fund Size (Millions) Number of Holdings Portfolio Turnover $924 221 8.16% | |
| Holdings [Text Block] | Portfolio Holdings (as of 5/31/24) Sector Allocation (Based on Net Assets) | |
| Material Fund Change [Text Block] | • On May 17, 2024, the Fund commenced offering Class Z shares. • As of the close of business on May 17, 2024, pursuant to an Agreement and Plan of Reorganization (“Reorganization”) previously approved by the Fund’s Board of Trustees (the “Board”), all of the assets, subject to the liabilities, of BNY Mellon New York Tax Exempt Bond Fund, Inc. (the “Acquired Fund”) were transferred to the Fund in a tax free exchange at cost basis for Class Z of Common Stock of equal value. The purpose of the transaction was to combine two funds with comparable investment objectives and strategies. Shareholders of the Acquired Fund share class received Class Z shares of the Fund in an amount equal to the aggregate net asset value of their investment in the Fund’s Class Z shares at the time of the exchange. This is a summary of certain changes to the Fund since May 17, 2024. For more complete information, you may review the Fund’s next prospectus, which we expect to be available by March 31, 2025 at im.bnymellon.com/literaturecenter or upon request at 1-800-373-9387. | |
| Summary of Change Legend [Text Block] | This is a summary of certain changes to the Fund since May 17, 2024. For more complete information, you may review the Fund’s next prospectus, which we expect to be available by March 31, 2025 at im.bnymellon.com/literaturecenter or upon request at 1-800-373-9387. | |
| Updated Prospectus Phone Number | 1-800-373-9387 | |
| Updated Prospectus Web Address | im.bnymellon.com/literaturecenter | |
| [1] During the period, fees were waived and/or expenses reimbursed pursuant to an agreement with the Fund’s investment adviser, BNY Mellon Investment Adviser, Inc. If this agreement is not extended in the future, expenses could be higher. Annualized During the period, fees were waived and/or expenses reimbursed pursuant to an agreement with the Fund’s investment adviser, BNY Mellon Investment Adviser, Inc. If this agreement is not extended in the future, expenses could be higher. Annualized During the period, fees were waived and/or expenses reimbursed pursuant to an agreement with the Fund’s investment adviser, BNY Mellon Investment Adviser, Inc. If this agreement is not extended in the future, expenses could be higher. Annualized Annualized During the period, fees were waived and/or expenses reimbursed pursuant to an agreement with the Fund’s investment adviser, BNY Mellon Investment Adviser, Inc. If this agreement is not extended in the future, expenses could be higher. Annualized | ||
| Shareholder Report, Holdings (Details) - BNY Mellon New York AMT-Free Municipal Bond Fund | May 31, 2024 |
| Class A – PSNYX | Other | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 24.20% |
| Class A – PSNYX | Multifamily Housing | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 1.20% |
| Class A – PSNYX | Nursing Homes | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 1.50% |
| Class A – PSNYX | Utilities | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 3.60% |
| Class A – PSNYX | Power | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 4.50% |
| Class A – PSNYX | Tobacco Settlement | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 4.90% |
| Class A – PSNYX | Medical | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 5.90% |
| Class A – PSNYX | General Obligation | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 6.30% |
| Class A – PSNYX | Water | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 7.80% |
| Class A – PSNYX | Development | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 8.30% |
| Class A – PSNYX | Airport | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 8.70% |
| Class A – PSNYX | Transportation | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 10.60% |
| Class A – PSNYX | Education | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 12.50% |
| Class C– PNYCX | Other | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 24.20% |
| Class C– PNYCX | Multifamily Housing | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 1.20% |
| Class C– PNYCX | Nursing Homes | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 1.50% |
| Class C– PNYCX | Utilities | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 3.60% |
| Class C– PNYCX | Power | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 4.50% |
| Class C– PNYCX | Tobacco Settlement | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 4.90% |
| Class C– PNYCX | Medical | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 5.90% |
| Class C– PNYCX | General Obligation | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 6.30% |
| Class C– PNYCX | Water | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 7.80% |
| Class C– PNYCX | Development | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 8.30% |
| Class C– PNYCX | Airport | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 8.70% |
| Class C– PNYCX | Transportation | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 10.60% |
| Class C– PNYCX | Education | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 12.50% |
| Class I – DNYIX | Other | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 24.20% |
| Class I – DNYIX | Multifamily Housing | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 1.20% |
| Class I – DNYIX | Nursing Homes | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 1.50% |
| Class I – DNYIX | Utilities | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 3.60% |
| Class I – DNYIX | Power | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 4.50% |
| Class I – DNYIX | Tobacco Settlement | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 4.90% |
| Class I – DNYIX | Medical | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 5.90% |
| Class I – DNYIX | General Obligation | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 6.30% |
| Class I – DNYIX | Water | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 7.80% |
| Class I – DNYIX | Development | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 8.30% |
| Class I – DNYIX | Airport | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 8.70% |
| Class I – DNYIX | Transportation | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 10.60% |
| Class I – DNYIX | Education | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 12.50% |
| Class Y – DNYYX | Other | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 24.20% |
| Class Y – DNYYX | Multifamily Housing | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 1.20% |
| Class Y – DNYYX | Nursing Homes | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 1.50% |
| Class Y – DNYYX | Utilities | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 3.60% |
| Class Y – DNYYX | Power | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 4.50% |
| Class Y – DNYYX | Tobacco Settlement | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 4.90% |
| Class Y – DNYYX | Medical | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 5.90% |
| Class Y – DNYYX | General Obligation | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 6.30% |
| Class Y – DNYYX | Water | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 7.80% |
| Class Y – DNYYX | Development | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 8.30% |
| Class Y – DNYYX | Airport | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 8.70% |
| Class Y – DNYYX | Transportation | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 10.60% |
| Class Y – DNYYX | Education | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 12.50% |
| Class Z – DNYAX | Other | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 24.20% |
| Class Z – DNYAX | Multifamily Housing | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 1.20% |
| Class Z – DNYAX | Nursing Homes | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 1.50% |
| Class Z – DNYAX | Utilities | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 3.60% |
| Class Z – DNYAX | Power | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 4.50% |
| Class Z – DNYAX | Tobacco Settlement | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 4.90% |
| Class Z – DNYAX | Medical | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 5.90% |
| Class Z – DNYAX | General Obligation | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 6.30% |
| Class Z – DNYAX | Water | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 7.80% |
| Class Z – DNYAX | Development | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 8.30% |
| Class Z – DNYAX | Airport | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 8.70% |
| Class Z – DNYAX | Transportation | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 10.60% |
| Class Z – DNYAX | Education | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 12.50% |
