v3.24.2
Shareholder Report
6 Months Ended
May 31, 2024
USD ($)
shares
Shareholder Report [Line Items]  
Document Type N-CSRS
Amendment Flag false
Registrant Name Fidelity Court Street Trust II
Entity Central Index Key 0000880709
Entity Investment Company Type N-1A
Document Period End Date May 31, 2024
Fidelity New Jersey Municipal Money Market Fund - Institutional Class  
Shareholder Report [Line Items]  
Fund Name Fidelity® New Jersey Municipal Money Market Fund
Class Name Fidelity® New Jersey Municipal Money Market Fund Institutional Class
Trading Symbol FSKXX
Annual or Semi-Annual Statement [Text Block] This semi-annual shareholder report contains information about Fidelity® New Jersey Municipal Money Market Fund for the period December 1, 2023 to May 31, 2024.
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
 
Institutional Class
$ 10 
0.20%
 
 
Expenses Paid, Amount $ 10
Expense Ratio, Percent 0.20%
Net Assets $ 1,134,480,995
Holdings Count | shares 185
Additional Fund Statistics [Text Block] Key Fund Statistics  
(as of May 31, 2024)
 
KEY FACTS 
 
 
Fund Size
$1,134,480,995
 
 
Number of Holdings
185
 
 
Holdings [Text Block]   EFFECTIVE MATURITY DIVERSIFICATION (% of Fund's net assets)   Days   1-7 69.3   8-30 1.8   31-60 6.7   61-90 2.7   91-180 4.8   >180 11.1         Variable Rate Demand Notes (VRDNs) 35.4 Tender Option Bond 24.2 Municipal Securities 24.1 Commercial Paper 1.3 Net Other Assets (Liabilities) 15.0 ASSET ALLOCATION (% of Fund's net assets)
Fidelity New Jersey Municipal Money Market Fund - Premium Class  
Shareholder Report [Line Items]  
Fund Name Fidelity® New Jersey Municipal Money Market Fund
Class Name Fidelity® New Jersey Municipal Money Market Fund Premium Class
Trading Symbol FSJXX
Annual or Semi-Annual Statement [Text Block] This semi-annual shareholder report contains information about Fidelity® New Jersey Municipal Money Market Fund for the period December 1, 2023 to May 31, 2024.
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
 
Premium Class
$ 15 
0.30%
 
 
Expenses Paid, Amount $ 15
Expense Ratio, Percent 0.30%
Net Assets $ 1,134,480,995
Holdings Count | shares 185
Additional Fund Statistics [Text Block] Key Fund Statistics  
(as of May 31, 2024)
 
KEY FACTS 
 
 
Fund Size
$1,134,480,995
 
 
Number of Holdings
185
 
 
Holdings [Text Block]   EFFECTIVE MATURITY DIVERSIFICATION (% of Fund's net assets)   Days   1-7 69.3   8-30 1.8   31-60 6.7   61-90 2.7   91-180 4.8   >180 11.1         Variable Rate Demand Notes (VRDNs) 35.4 Tender Option Bond 24.2 Municipal Securities 24.1 Commercial Paper 1.3 Net Other Assets (Liabilities) 15.0 ASSET ALLOCATION (% of Fund's net assets)
Fidelity New Jersey Municipal Money Market Fund  
Shareholder Report [Line Items]  
Fund Name Fidelity® New Jersey Municipal Money Market Fund
Class Name Fidelity® New Jersey Municipal Money Market Fund
Trading Symbol FAYXX
Annual or Semi-Annual Statement [Text Block] This semi-annual shareholder report contains information about Fidelity® New Jersey Municipal Money Market Fund for the period December 1, 2023 to May 31, 2024.
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 Jersey Municipal Money Market Fund
$ 21 
0.42%
 
 
Expenses Paid, Amount $ 21
Expense Ratio, Percent 0.42%
Net Assets $ 1,134,480,995
Holdings Count | shares 185
Additional Fund Statistics [Text Block] Key Fund Statistics  
(as of May 31, 2024)
 
KEY FACTS 
 
 
Fund Size
$1,134,480,995
 
 
Number of Holdings
185
 
 
Holdings [Text Block]   EFFECTIVE MATURITY DIVERSIFICATION (% of Fund's net assets)   Days   1-7 69.3   8-30 1.8   31-60 6.7   61-90 2.7   91-180 4.8   >180 11.1         Variable Rate Demand Notes (VRDNs) 35.4 Tender Option Bond 24.2 Municipal Securities 24.1 Commercial Paper 1.3 Net Other Assets (Liabilities) 15.0 ASSET ALLOCATION (% of Fund's net assets)