Label

Element

Value

Risk/Return:

rr_RiskReturnAbstract

Document Type

dei_DocumentType

Other

Document Period End Date

dei_DocumentPeriodEndDate

Apr. 10, 2017

Entity Registrant Name

dei_EntityRegistrantName

RYDEX SERIES FUNDS

Central Index Key

dei_EntityCentralIndexKey

0000899148

Amendment Flag

dei_AmendmentFlag

false

Document Creation Date

dei_DocumentCreationDate

Apr. 10, 2017

Document Effective Date

dei_DocumentEffectiveDate

Apr. 10, 2017

Prospectus Date

rr_ProspectusDate

Aug. 01, 2017

Supplement [Text Block]

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Rydex Series Funds

805 King Farm Blvd., Suite 600

Rockville, Maryland 20850

RYDEX SERIES FUNDS

Rydex Domestic Equity Funds

Rydex Sector Funds

Rydex International Equity Funds

Rydex Specialty Funds

Rydex Fixed Income Funds

Guggenheim Alternative Funds

Rydex Money Market Fund

(each, a “Fund” and, collectively, the “Funds”)

April 10, 2017

Supplement dated April 10, 2017 to the currently effective Rydex Series Funds Class A, Class C and Institutional Class shares Summary Prospectuses dated August 1, 2016, as revised (collectively, the “Summary Prospectuses”).

This supplement provides new and additional information beyond that contained in the Summary Prospectuses and should be read in conjunction with the Summary Prospectuses.

Effective immediately, customers of Merrill Lynch, Pierce, Fenner & Smith Incorporated (“Merrill Lynch”) purchasing Class A shares and Class C shares of the Funds through Merrill Lynch may be eligible for certain share class conversion features and sales load waivers and discounts.

Expense Narrative [Text Block]

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The Summary Prospectuses are hereby revised as specified below to include information regarding such sales load waivers and discounts. Additional information regarding share class availability and applicable sales charge waivers and discounts may be found in the Funds’ Statutory Prospectus and Statement of Additional Information and also may be viewed at www.guggenheiminvestments.com/mf/share-class-information.

In each Fund’s “Fund Summary” section, the introductory paragraph to the fee table under the heading “Fees and Expenses of the Fund” is deleted in its entirety and replaced as follows.

For each Rydex Domestic Equity Fund, Rydex Sector Fund, Rydex International Equity Fund, Rydex Specialty Fund, Rydex Fixed Income Fund and the Rydex Money Market Fund:

FEES AND EXPENSES OF THE FUND

This table describes the fees and expenses that you may pay if you buy and hold Class A shares or Class C shares of the Fund. You may qualify for sales charge discounts if you and your family invest, or agree to invest in the future, at least $100,000 in certain funds in the Guggenheim Investments family of funds. More information about these and other discounts is available from your financial professional and under the “Sales Charges” section on page 436 of the Prospectus, in Appendix A to the Prospectus - “Sales Charge Waivers and Discounts Available Through Intermediaries”, and in the “Sales Charges, Reductions, and Waivers” section beginning on page 81 of the Fund’s Statement of Additional Information (the “SAI”).

For each Guggenheim Alternative Fund:

FEES AND EXPENSES OF THE FUND

This table describes the fees and expenses that you may pay if you buy and hold Class A shares, Class C shares or Institutional shares of the Fund. You may qualify for sales charge discounts if you and your family invest, or agree to invest in the future, at least $100,000 in certain funds in the Guggenheim Investments family of funds. More information about these and other discounts is available from your financial professional and under the “Sales Charges” section on page 436 of the Prospectus, in Appendix A to the Prospectus - “Sales Charge Waivers and Discounts Available Through Intermediaries”, and in the “Sales Charges, Reductions, and Waivers” section beginning on page 81 of the Fund’s Statement of Additional Information (the “SAI”).

Supplement Closing [Text Block]

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Please retain this supplement for future reference.

RSF-SUM-SUP3-0417x0817