Expense Example, No Redemption {- Franklin DynaTech Fund} - Franklin Custodian Funds-31 - Franklin DynaTech Fund - Class C	Feb. 01, 2021 USD ($)
Expense Example, No Redemption:
1 Year	$ 163
3 Years	507
5 Years	875
10 Years	$ 1,911

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You would pay the following expenses if you did not redeem your shares. Include the second 1-, 3-, 5-, and 10-year periods and related narrative explanation only if a sales charge (load) or other fee is charged upon redemption.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Form
-Number N-1A
-Chapter A
-Section 3
-Subsection example
-Paragraph 2
-Subparagraph 1

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+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Form
-Number N-1A
-Chapter A
-Section 3
-Subsection example
-Paragraph 2
-Subparagraph 1

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+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Form
-Number N-1A
-Chapter A
-Section 3
-Subsection instructions
-Paragraph 4
-Subparagraph f

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- Definition

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Form
-Number N-1A
-Chapter A
-Section 3
-Subsection instructions
-Paragraph 4
-Subparagraph f

+ Details

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