v3.26.1
Shareholder Report
 6 Months Ended
Feb. 28, 2026
USD ($)
$ / shares
Shareholder Report [Line Items]  
Document Type N-CSRS
Amendment Flag false
Registrant Name Franklin Strategic Series
Entity Central Index Key 0000872625
Entity Investment Company Type N-1A
Document Period End Date Feb. 28, 2026
Shareholder Report Annual or Semi-Annual semi-annual shareholder report
Class Advisor  
Shareholder Report [Line Items]  
Fund Name Franklin Templeton SMACS: Series CH
Class Name Franklin Templeton SMACS: Series CH
No Trading Symbol true
Annual or Semi-Annual Statement [Text Block] This semi-annual shareholder report contains important information about Franklin Templeton SMACS: Series CH for the period September 1, 2025, to February 28, 2026.
Additional Information [Text Block] You can find additional information about the Fund at https://www.franklintempleton.com/regulatory-fund-documents. You can also request this information by contacting us at (800) DIAL BEN/342-5236.
Additional Information Phone Number (800) DIAL BEN/342-5236
Additional Information Website https://www.franklintempleton.com/regulatory-fund-documents
Expenses [Text Block]
WHAT WERE THE FUND COSTS FOR THE LAST SIX MONTHS? (based on a hypothetical $10,000 investment)
Fund Name
Costs of a $10,000 investment
Costs paid as a percentage of a $10,000 investment*,†
Franklin Templeton SMACS: Series CH1
$0
0.00%
[1],[2],[3]
Expenses Paid, Amount $ 0 [1]
Expense Ratio, Percent 0.00% [1]
Net Assets $ 35,948,877
Holdings Count | $ / shares 86
Investment Company Portfolio Turnover 7.69%
Additional Fund Statistics [Text Block]
KEY FUND STATISTICS (as of February 28, 2026)
Total Net Assets
$35,948,877
Total Number of Portfolio Holdings
86
Portfolio Turnover Rate
7.69%
Holdings [Text Block]
WHAT DID THE FUND INVEST IN? (as of February 28, 2026)
Portfolio Composition* (% of Total Investments)
image
 [4]
Updated Prospectus Web Address https://www.franklintempleton.com/regulatory-fund-documents
Class Advisor  
Shareholder Report [Line Items]  
Fund Name Franklin Templeton SMACS: Series E
Class Name Franklin Templeton SMACS: Series E
No Trading Symbol true
Annual or Semi-Annual Statement [Text Block] This semi-annual shareholder report contains important information about Franklin Templeton SMACS: Series E for the period September 1, 2025, to February 28, 2026.
Additional Information [Text Block] You can find additional information about the Fund at https://www.franklintempleton.com/regulatory-fund-documents. You can also request this information by contacting us at (800) DIAL BEN/342-5236.
Additional Information Phone Number (800) DIAL BEN/342-5236
Additional Information Website https://www.franklintempleton.com/regulatory-fund-documents
Expenses [Text Block]
WHAT WERE THE FUND COSTS FOR THE LAST SIX MONTHS? (based on a hypothetical $10,000 investment)
Fund Name
Costs of a $10,000 investment
Costs paid as a percentage of a $10,000 investment*,†
Franklin Templeton SMACS: Series E1
$0
0.00%
[5],[6],[7]
Expenses Paid, Amount $ 0 [5]
Expense Ratio, Percent 0.00% [5]
Net Assets $ 531,218,082
Holdings Count | $ / shares 118
Investment Company Portfolio Turnover 54.54%
Additional Fund Statistics [Text Block]
KEY FUND STATISTICS (as of February 28, 2026)
Total Net Assets
$531,218,082
Total Number of Portfolio Holdings
118
Portfolio Turnover Rate
54.54%
Holdings [Text Block]
WHAT DID THE FUND INVEST IN? (as of February 28, 2026)
Portfolio Composition* (% of Total Investments)
image
 [8]
Updated Prospectus Web Address https://www.franklintempleton.com/regulatory-fund-documents
Class Advisor  
Shareholder Report [Line Items]  
Fund Name Franklin Templeton SMACS: Series H
Class Name Franklin Templeton SMACS: Series H
No Trading Symbol true
Annual or Semi-Annual Statement [Text Block] This semi-annual shareholder report contains important information about Franklin Templeton SMACS: Series H for the period September 1, 2025, to February 28, 2026.
Additional Information [Text Block] You can find additional information about the Fund at https://www.franklintempleton.com/regulatory-fund-documents. You can also request this information by contacting us at (800) DIAL BEN/342-5236.
Additional Information Phone Number (800) DIAL BEN/342-5236
Additional Information Website https://www.franklintempleton.com/regulatory-fund-documents
Expenses [Text Block]
WHAT WERE THE FUND COSTS FOR THE LAST SIX MONTHS? (based on a hypothetical $10,000 investment)
Fund Name
Costs of a $10,000 investment
Costs paid as a percentage of a $10,000 investment*,†
Franklin Templeton SMACS: Series H1
$0
0.00%
[9],[10],[11]
Expenses Paid, Amount $ 0 [9]
Expense Ratio, Percent 0.00% [9]
Net Assets $ 41,846,001
Holdings Count | $ / shares 223
Investment Company Portfolio Turnover 9.15%
Additional Fund Statistics [Text Block]
KEY FUND STATISTICS (as of February 28, 2026)
Total Net Assets
$41,846,001
Total Number of Portfolio Holdings
223
Portfolio Turnover Rate
9.15%
Holdings [Text Block]
WHAT DID THE FUND INVEST IN? (as of February 28, 2026)
Portfolio Composition* (% of Total Investments)
image
 [12]
Updated Prospectus Web Address https://www.franklintempleton.com/regulatory-fund-documents
Class Advisor  
Shareholder Report [Line Items]  
Fund Name Franklin Templeton SMACS: Series I
Class Name Franklin Templeton SMACS: Series I
No Trading Symbol true
Annual or Semi-Annual Statement [Text Block] This semi-annual shareholder report contains important information about Franklin Templeton SMACS: Series I for the period September 1, 2025, to February 28, 2026.
Additional Information [Text Block] You can find additional information about the Fund at https://www.franklintempleton.com/regulatory-fund-documents. You can also request this information by contacting us at (800) DIAL BEN/342-5236.
Additional Information Phone Number (800) DIAL BEN/342-5236
Additional Information Website https://www.franklintempleton.com/regulatory-fund-documents
Expenses [Text Block]
WHAT WERE THE FUND COSTS FOR THE LAST SIX MONTHS? (based on a hypothetical $10,000 investment)
Fund Name
Costs of a $10,000 investment
Costs paid as a percentage of a $10,000 investment*,†
Franklin Templeton SMACS: Series I1
$0
0.00%
[13],[14],[15]
Expenses Paid, Amount $ 0 [13]
Expense Ratio, Percent 0.00% [13]
Net Assets $ 784,848,097
Holdings Count | $ / shares 178
Investment Company Portfolio Turnover 20.79%
Additional Fund Statistics [Text Block]
KEY FUND STATISTICS (as of February 28, 2026)
Total Net Assets
$784,848,097
Total Number of Portfolio Holdings
178
Portfolio Turnover Rate
20.79%
Holdings [Text Block]
WHAT DID THE FUND INVEST IN? (as of February 28, 2026)
Portfolio Composition*  (% of Total Investments)
image
 [16]
Updated Prospectus Web Address https://www.franklintempleton.com/regulatory-fund-documents
[1]
1 Does not reflect the effect of fees and expenses associated with a separately managed account, or a management fee or other operating expenses of the Fund.
[2]
* Reflects fee waivers and/or expense reimbursements, without which expenses would have been higher.
[3]
† Annualized.
[4]
* Does not include derivatives, except purchased options, if any.  
[5]
1 Does not reflect the effect of fees and expenses associated with a separately managed account, or a management fee or other operating expenses of the Fund.
[6]
* Reflects fee waivers and/or expense reimbursements, without which expenses would have been higher.
[7]
† Annualized.
[8]
* Does not include derivatives, except purchased options, if any.  
[9]
1 Does not reflect the effect of fees and expenses associated with a separately managed account, or a management fee or other operating expenses of the Fund.
[10]
* Reflects fee waivers and/or expense reimbursements, without which expenses would have been higher.
[11]
† Annualized.
[12]
* Does not include derivatives, except purchased options, if any.  
[13]
1 Does not reflect the effect of fees and expenses associated with a separately managed account, or a management fee or other operating expenses of the Fund.
[14]
* Reflects fee waivers and/or expense reimbursements, without which expenses would have been higher.
[15]
† Annualized.
[16]
* Does not include derivatives, except purchased options, if any.