v3.26.3
Shareholder Report
 6 Months Ended
Jul. 31, 2026
USD ($)
shares
Shareholder Report [Line Items]  
Document Type N-CSRS
Amendment Flag false
Registrant Name Fidelity New York Municipal Trust
Entity Central Index Key 0000718581
Entity Investment Company Type N-1A
Document Period End Date Jul. 31, 2026
Fidelity New York Municipal Income Fund  
Shareholder Report [Line Items]  
Fund Name Fidelity® New York Municipal Income Fund
Class Name Fidelity® New York Municipal Income Fund
Trading Symbol FTFMX
Annual or Semi-Annual Statement [Text Block] This semi-annual shareholder report contains information about Fidelity® New York Municipal Income Fund for the period February 1, 2026 to July 31, 2026.
Shareholder Report Annual or Semi-Annual semi-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.
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 six months?
(based on hypothetical $10,000 investment)
 
 
 
Costs of a $10,000 investment
Costs paid as a percentage of a $10,000 investment
 
Fidelity® New York Municipal Income Fund 
$ 22 
0.45%
  
Expenses Paid, Amount $ 22
Expense Ratio, Percent 0.45%
Net Assets $ 1,283,549,284
Holdings Count | shares 450
Investment Company Portfolio Turnover 13.00%
Additional Fund Statistics [Text Block] Key Fund Statistics
(as of July 31, 2026)
 
KEY FACTS 
  
  
Fund Size
$1,283,549,284
  
Number of Holdings
450
  
Portfolio Turnover
13%
  
Holdings [Text Block]   REVENUE SOURCES (% of Fund's net assets) Transportation 26.7   Special Tax 20.2   General Obligations 17.6   Health Care 8.5   Housing 8.4   Education 6.9   Others(Individually Less Than 5%) 8.3   96.6       AAA 1.7 AA 60.6 A 20.3 BBB 11.2 B 1.1 Not Rated 1.7 Short-Term Investments and Net Other Assets (Liabilities) 3.4 QUALITY DIVERSIFICATION (% of Fund's net assets)     AAA - 1.7                                  AA - 60.6                                  A - 20.3                                   BBB - 11.2                                 B - 1.1                                    Not Rated - 1.7                            Short-Term Investments and Net Other Assets (Liabilities) - 3.4   We have used ratings from Moody's Investors Service, Inc. Where Moody's® ratings are not available, we have used S&P® ratings. All ratings are as of the date indicated and do not reflect subsequent changes.        
Fidelity Advisor New York Municipal Income Fund - Class Z  
Shareholder Report [Line Items]  
Fund Name Fidelity® New York Municipal Income Fund
Class Name Fidelity Advisor® New York Municipal Income Fund Class Z
Trading Symbol FIJAX
Annual or Semi-Annual Statement [Text Block] This semi-annual shareholder report contains information about Fidelity® New York Municipal Income Fund for the period February 1, 2026 to July 31, 2026.
Shareholder Report Annual or Semi-Annual semi-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.
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 six months?
(based on hypothetical $10,000 investment)
 
 
 
Costs of a $10,000 investment
Costs paid as a percentage of a $10,000 investment
 
Class Z 
$ 21 
0.42%
  
Expenses Paid, Amount $ 21
Expense Ratio, Percent 0.42%
Net Assets $ 1,283,549,284
Holdings Count | shares 450
Investment Company Portfolio Turnover 13.00%
Additional Fund Statistics [Text Block] Key Fund Statistics
(as of July 31, 2026)
 
KEY FACTS 
  
  
Fund Size
$1,283,549,284
  
Number of Holdings
450
  
Portfolio Turnover
13%
  
Holdings [Text Block]   REVENUE SOURCES (% of Fund's net assets) Transportation 26.7   Special Tax 20.2   General Obligations 17.6   Health Care 8.5   Housing 8.4   Education 6.9   Others(Individually Less Than 5%) 8.3   96.6       AAA 1.7 AA 60.6 A 20.3 BBB 11.2 B 1.1 Not Rated 1.7 Short-Term Investments and Net Other Assets (Liabilities) 3.4 QUALITY DIVERSIFICATION (% of Fund's net assets)     AAA - 1.7                                  AA - 60.6                                  A - 20.3                                   BBB - 11.2                                 B - 1.1                                    Not Rated - 1.7                            Short-Term Investments and Net Other Assets (Liabilities) - 3.4   We have used ratings from Moody's Investors Service, Inc. Where Moody's® ratings are not available, we have used S&P® ratings. All ratings are as of the date indicated and do not reflect subsequent changes.        
Fidelity Advisor New York Municipal Income Fund - Class M  
Shareholder Report [Line Items]  
Fund Name Fidelity® New York Municipal Income Fund
Class Name Fidelity Advisor® New York Municipal Income Fund Class M
Trading Symbol FNYPX
Annual or Semi-Annual Statement [Text Block] This semi-annual shareholder report contains information about Fidelity® New York Municipal Income Fund for the period February 1, 2026 to July 31, 2026.
Shareholder Report Annual or Semi-Annual semi-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.
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 six months?
(based on hypothetical $10,000 investment)
 
 
 
Costs of a $10,000 investment
Costs paid as a percentage of a $10,000 investment
 
Class M 
$ 36 
0.72%
  
Expenses Paid, Amount $ 36
Expense Ratio, Percent 0.72%
Net Assets $ 1,283,549,284
Holdings Count | shares 450
Investment Company Portfolio Turnover 13.00%
Additional Fund Statistics [Text Block] Key Fund Statistics
(as of July 31, 2026)
 
KEY FACTS 
  
  
Fund Size
$1,283,549,284
  
Number of Holdings
450
  
Portfolio Turnover
13%
  
Holdings [Text Block]   REVENUE SOURCES (% of Fund's net assets) Transportation 26.7   Special Tax 20.2   General Obligations 17.6   Health Care 8.5   Housing 8.4   Education 6.9   Others(Individually Less Than 5%) 8.3   96.6       AAA 1.7 AA 60.6 A 20.3 BBB 11.2 B 1.1 Not Rated 1.7 Short-Term Investments and Net Other Assets (Liabilities) 3.4 QUALITY DIVERSIFICATION (% of Fund's net assets)     AAA - 1.7                                  AA - 60.6                                  A - 20.3                                   BBB - 11.2                                 B - 1.1                                    Not Rated - 1.7                            Short-Term Investments and Net Other Assets (Liabilities) - 3.4   We have used ratings from Moody's Investors Service, Inc. Where Moody's® ratings are not available, we have used S&P® ratings. All ratings are as of the date indicated and do not reflect subsequent changes.        
Fidelity Advisor New York Municipal Income Fund - Class I  
Shareholder Report [Line Items]  
Fund Name Fidelity® New York Municipal Income Fund
Class Name Fidelity Advisor® New York Municipal Income Fund Class I
Trading Symbol FEMIX
Annual or Semi-Annual Statement [Text Block] This semi-annual shareholder report contains information about Fidelity® New York Municipal Income Fund for the period February 1, 2026 to July 31, 2026.
Shareholder Report Annual or Semi-Annual semi-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.
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 six months?
(based on hypothetical $10,000 investment)
 
 
 
Costs of a $10,000 investment
Costs paid as a percentage of a $10,000 investment
 
Class I 
$ 26 
0.53%
  
Expenses Paid, Amount $ 26
Expense Ratio, Percent 0.53%
Net Assets $ 1,283,549,284
Holdings Count | shares 450
Investment Company Portfolio Turnover 13.00%
Additional Fund Statistics [Text Block] Key Fund Statistics
(as of July 31, 2026)
 
KEY FACTS 
  
  
Fund Size
$1,283,549,284
  
Number of Holdings
450
  
Portfolio Turnover
13%
  
Holdings [Text Block]   REVENUE SOURCES (% of Fund's net assets) Transportation 26.7   Special Tax 20.2   General Obligations 17.6   Health Care 8.5   Housing 8.4   Education 6.9   Others(Individually Less Than 5%) 8.3   96.6       AAA 1.7 AA 60.6 A 20.3 BBB 11.2 B 1.1 Not Rated 1.7 Short-Term Investments and Net Other Assets (Liabilities) 3.4 QUALITY DIVERSIFICATION (% of Fund's net assets)     AAA - 1.7                                  AA - 60.6                                  A - 20.3                                   BBB - 11.2                                 B - 1.1                                    Not Rated - 1.7                            Short-Term Investments and Net Other Assets (Liabilities) - 3.4   We have used ratings from Moody's Investors Service, Inc. Where Moody's® ratings are not available, we have used S&P® ratings. All ratings are as of the date indicated and do not reflect subsequent changes.        
Fidelity Advisor New York Municipal Income Fund - Class C  
Shareholder Report [Line Items]  
Fund Name Fidelity® New York Municipal Income Fund
Class Name Fidelity Advisor® New York Municipal Income Fund Class C
Trading Symbol FNYCX
Annual or Semi-Annual Statement [Text Block] This semi-annual shareholder report contains information about Fidelity® New York Municipal Income Fund for the period February 1, 2026 to July 31, 2026.
Shareholder Report Annual or Semi-Annual semi-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.
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 six months?
(based on hypothetical $10,000 investment)
 
 
 
Costs of a $10,000 investment
Costs paid as a percentage of a $10,000 investment
 
Class C 
$ 73 
1.47%
  
Expenses Paid, Amount $ 73
Expense Ratio, Percent 1.47%
Net Assets $ 1,283,549,284
Holdings Count | shares 450
Investment Company Portfolio Turnover 13.00%
Additional Fund Statistics [Text Block] Key Fund Statistics
(as of July 31, 2026)
 
KEY FACTS 
  
  
Fund Size
$1,283,549,284
  
Number of Holdings
450
  
Portfolio Turnover
13%
  
Holdings [Text Block]   REVENUE SOURCES (% of Fund's net assets) Transportation 26.7   Special Tax 20.2   General Obligations 17.6   Health Care 8.5   Housing 8.4   Education 6.9   Others(Individually Less Than 5%) 8.3   96.6       AAA 1.7 AA 60.6 A 20.3 BBB 11.2 B 1.1 Not Rated 1.7 Short-Term Investments and Net Other Assets (Liabilities) 3.4 QUALITY DIVERSIFICATION (% of Fund's net assets)     AAA - 1.7                                  AA - 60.6                                  A - 20.3                                   BBB - 11.2                                 B - 1.1                                    Not Rated - 1.7                            Short-Term Investments and Net Other Assets (Liabilities) - 3.4   We have used ratings from Moody's Investors Service, Inc. Where Moody's® ratings are not available, we have used S&P® ratings. All ratings are as of the date indicated and do not reflect subsequent changes.        
Fidelity Advisor New York Municipal Income Fund - Class A  
Shareholder Report [Line Items]  
Fund Name Fidelity® New York Municipal Income Fund
Class Name Fidelity Advisor® New York Municipal Income Fund Class A
Trading Symbol FNMAX
Annual or Semi-Annual Statement [Text Block] This semi-annual shareholder report contains information about Fidelity® New York Municipal Income Fund for the period February 1, 2026 to July 31, 2026.
Shareholder Report Annual or Semi-Annual semi-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.
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 six months?
(based on hypothetical $10,000 investment)
 
 
 
Costs of a $10,000 investment
Costs paid as a percentage of a $10,000 investment
 
Class A 
$ 38 
0.76%
  
Expenses Paid, Amount $ 38
Expense Ratio, Percent 0.76%
Net Assets $ 1,283,549,284
Holdings Count | shares 450
Investment Company Portfolio Turnover 13.00%
Additional Fund Statistics [Text Block] Key Fund Statistics
(as of July 31, 2026)
 
KEY FACTS 
  
  
Fund Size
$1,283,549,284
  
Number of Holdings
450
  
Portfolio Turnover
13%
  
Holdings [Text Block]   REVENUE SOURCES (% of Fund's net assets) Transportation 26.7   Special Tax 20.2   General Obligations 17.6   Health Care 8.5   Housing 8.4   Education 6.9   Others(Individually Less Than 5%) 8.3   96.6       AAA 1.7 AA 60.6 A 20.3 BBB 11.2 B 1.1 Not Rated 1.7 Short-Term Investments and Net Other Assets (Liabilities) 3.4 QUALITY DIVERSIFICATION (% of Fund's net assets)     AAA - 1.7                                  AA - 60.6                                  A - 20.3                                   BBB - 11.2                                 B - 1.1                                    Not Rated - 1.7                            Short-Term Investments and Net Other Assets (Liabilities) - 3.4   We have used ratings from Moody's Investors Service, Inc. Where Moody's® ratings are not available, we have used S&P® ratings. All ratings are as of the date indicated and do not reflect subsequent changes.