485BPOS

As filed with the Securities and Exchange Commission on July 10, 2018

Registration Nos. 2-75503, 811-03364

SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, D.C. 20549

FORM N-1A

REGISTRATION STATEMENT UNDER THE SECURITIES ACT OF 1933
Pre-Effective Amendment No.	(   )
Post-Effective Amendment No. 157	(X)
and/or
REGISTRATION STATEMENT UNDER THE INVESTMENT COMPANY ACT OF 1940
Amendment No. 157	(X)

GREAT-WEST FUNDS, INC.

(Exact Name of Registrant as Specified in Charter)

8515 E. Orchard Road

Greenwood Village, Colorado 80111

Registrant’s Telephone Number, including Area Code: (866) 831-7129

Scott C. Sipple

President & Chief Executive Officer

Great-West Funds, Inc.

8515 E. Orchard Road

Greenwood Village, Colorado 80111

(Address of Principal Executive Offices)

(Name and Address of Agent for Service)

Copies of Communications to:

Ryan L. Logsdon

Vice President, Counsel & Secretary

Great-West Funds, Inc.

8515 E. Orchard Road

Greenwood Village, Colorado 80111

It is proposed that this filing will become effective (check appropriate box)

X	immediately upon filing pursuant to paragraph (b) of Rule 485
	on , pursuant to paragraph (b) of Rule 485
	60 days after filing, pursuant to paragraph (a)(1) of Rule 485
	on , pursuant to paragraph (a)(1) of Rule 485
	75 days after filing, pursuant to paragraph (a)(2) of Rule 485
	on , pursuant to paragraph (a)(2) of Rule 485

If appropriate, check the following box:

this post-effective amendment designates a new effective date for a previously filed post-effective amendment.

SIGNATURES

Pursuant to the requirements of the Securities Act of 1933, as amended (the “Securities Act”) and the Investment Company Act, Great-West Funds certifies that it meets all of the requirements for effectiveness of this amended Registration Statement under Rule 485(b) under the Securities Act and has duly caused this Registration Statement to be signed on its behalf by the undersigned, duly authorized, in the City of Greenwood Village, and State of Colorado on the 10^th day of July 2018.

GREAT-WEST FUNDS, INC.
(Registrant)
By:	/s/ Scott C. Sipple
	Scott C. Sipple
	President and Chief Executive Officer

Pursuant to the requirements of the Securities Act, this amended Registration Statement has been signed below by the following persons in the capacities and on the date(s) indicated.

Signature	Title	Date
/s/ Gail H. Klapper	Director & Chair	July 10, 2018
Gail H. Klapper*
/s/ Stephen G. McConahey	Director	July 10, 2018
Stephen G. McConahey*
/s/ James A. Hillary	Director	July 10, 2018
James A. Hillary*
/s/ R. Timothy Hudner	Director	July 10, 2018
R. Timothy Hudner*
/s/ Steven A. Lake	Director	July 10, 2018
Steven A. Lake*
/s/ Scott C. Sipple	Director, President & Chief Executive	July 10, 2018
Scott C. Sipple	Officer
/s/ Mary C. Maiers	Chief Financial	July 10, 2018
Mary C. Maiers	Officer & Treasurer

*By:	/s/ Ryan L. Logsdon	July 10, 2018
	Ryan L. Logsdon (Attorney-in-fact)

Powers of Attorney for Ms. Klapper and Mr. McConahey are incorporated by reference to Registrant’s Post-Effective Amendment No. 141 to the Registration Statement filed on February 12, 2016 (File No. 2-75503). Powers of Attorney for Messrs. Hillary, Hudner and Lake are incorporated by reference to Registrant’s Post-Effective Amendment No. 144 to the Registration Statement filed on April 28, 2017 (File No. 2-75503).

EXHIBIT INDEX

Index No.	Description of Exhibit
EX-101.INS	XBRL Instance Document
EX-101.SCH	XBRL Taxonomy Extension Schema Document
EX-101.CAL	XBRL Taxonomy Extension Calculation Linkbase
EX-101.DEF	XBRL Taxonomy Extension Definition Linkbase
EX-101.LAB	XBRL Taxonomy Extension Labels Linkbase
EX-101.PRE	XBRL Taxonomy Extension Presentation Linkbase

XML

Label	Element	Value
Risk/Return:	rr_RiskReturnAbstract
Document Type	dei_DocumentType	485BPOS
Document Period End Date	dei_DocumentPeriodEndDate	Jun. 21, 2018
Registrant Name	dei_EntityRegistrantName	GREAT-WEST FUNDS INC
Central Index Key	dei_EntityCentralIndexKey	0000356476
Amendment Flag	dei_AmendmentFlag	false
Document Creation Date	dei_DocumentCreationDate	Jun. 21, 2018
Document Effective Date	dei_DocumentEffectiveDate	Jun. 25, 2018
Prospectus Date	rr_ProspectusDate	Jun. 25, 2018

XML

Great-West Core Strategies: Flexible Bond Fund

Fund Summary

Investment Objective

The Fund seeks to provide total return, consisting of two components: (1) changes in the market value of its portfolio holdings (both realized and unrealized appreciation); and (2) income received from its portfolio holdings.

Fees and Expenses of the Fund

This table describes the fees and expenses that you may pay if you buy and hold shares of the Fund. In addition to the fees and expenses described below, you may be required to pay your financial professional brokerage commissions when you purchase or sell Institutional Class shares.

Shareholder Fees (fees paid directly from your investment)

Shareholder Fees	Great-West Core Strategies: Flexible Bond Fund Institutional Class
Maximum Sales Charge (Load) Imposed on Purchases (as a percentage of offering price)	none
Maximum Deferred Sales Charge (Load)	none
Maximum Sales Charge (Load) Imposed on Reinvested Dividends	none
Redemption Fee	none
Exchange Fee	none

Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)

Annual Fund Operating Expenses	Great-West Core Strategies: Flexible Bond Fund Institutional Class	[1]
Management Fees	0.38%
Distribution and Service (12b-1) Fees	none
Other Expenses	0.37%
Total Annual Fund Operating Expenses	0.75%
Fee Waiver and Expense Reimbursement	0.30%	[2]
Total Annual Fund Operating Expenses After Fee Waiver and Expense Reimbursement	0.45%

Example

This Example is intended to help you compare the cost of investing in the Fund with the cost of investing in other mutual funds.

The Example assumes that you invest $10,000 in the Fund for the time periods indicated and applies whether you hold or redeem all of your shares at the end of each period. The Example also assumes that the expense reimbursement is in place for the first year, that your investment has a 5% return each year, that all dividends and capital gains are reinvested, and that the Fund’s operating expenses are the amount shown in the fee table and remain the same for the years shown. Although your actual costs may be higher or lower, based on these assumptions, your costs would be:

Expense Example	1 Year	3 Years
Great-West Core Strategies: Flexible Bond Fund | Institutional Class | USD ($)	46	209

Portfolio Turnover

The Fund pays transaction costs, such as commissions, when it buys and sells securities (or “turns over” its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when Fund shares are held in a taxable account. These costs, which are not reflected in annual fund operating expenses or in the example, affect the Fund’s performance.

Principal Investment Strategies

The following is a summary of the principal investment strategies of the Fund:

The Fund will, under normal circumstances, invest at least 80% of its net assets (plus the amount of borrowings for investment purposes) in a diversified portfolio of fixed income securities. Fixed income securities include corporate bonds, securities that have been issued or guaranteed by the U.S. government or its agencies or instrumentalities (“U.S. Government Securities”), mortgage- and asset-backed securities, and bank loans. The Fund primarily invests in investment grade securities, and may invest in securities of any maturity and of any duration.

The Fund may invest up to 20% of its total assets in preferred stock and convertible preferred stock. It may invest up to 20% of its total assets in foreign fixed income securities; however, fixed income securities of Canadian issuers and fixed income securities issued by supranational agencies (e.g., the World Bank) are not subject to this 20% limitation. It may also invest up to 35% of its total assets in securities of below investment grade quality (“high yield-high risk” or “junk”) bonds. The Fund may also enter into mortgage dollar rolls. In a mortgage dollar roll transaction, the Fund sells securities for delivery in the current month and simultaneously contracts to repurchase substantially similar securities (the same type, issuer, term and coupon) on a specified future date from the same party. For purposes of pursuing its investment goals, the Fund may, from time to time, enter into derivative contracts, including futures contracts on U.S. Treasury securities.

The Fund’s investment portfolio is managed by GWCM and Loomis, Sayles & Company, L.P. (“Loomis Sayles” or “Sub-Adviser”) serves as a sub-adviser to a portion of the Fund’s assets. GWCM seeks to invest in U.S. Government Securities by employing a “top-down,” or global, macroeconomic analysis of the fixed income markets, setting strategic targets to guide discussions on interest rate sensitivity and sector allocations, and then pairing these targets with “bottom-up,” or security-by-security, fundamental research to make individual investment decisions and help manage risks within each bond sector. Loomis Sayles seeks to invest in fixed income securities by focusing on good relative value based on the credit outlook of the issuer and maximum total return potential.

GWCM maintains a strategic allocation of the Fund’s assets with Loomis Sayles and reviews the asset allocations on a quarterly basis, or more frequently as deemed necessary. As of the date of this Prospectus, the target asset allocation is a 50% allocation of the Fund’s assets to each of GWCM and Loomis Sayles. Notwithstanding the target allocation, GWCM may change the asset allocations at any time and without shareholder notice or approval.

Principal Investment Risks

The following is a summary of the principal investment risks of investing in the Fund:

Bank Loan Risk - Bank loans often involve borrowers whose financial conditions are troubled or uncertain and companies that are highly leveraged. The market for bank loans may not be highly liquid and the Fund may have difficulty selling bank loans. These investments expose the Fund to the credit risk of both the financial institution and the underlying borrower. Bank loans generally are subject to legal or contractual restrictions on resale. In addition, bank loans may have trade settlement periods extending beyond seven days. Bank loans may be structured such that they are not securities under securities laws and subject to securities laws protections against fraud and misrepresentation. As such, there can be no assurances that fraud or misrepresentation will not occur with respect to bank loans in which the Fund invests.

Convertible Securities Risk - Convertible securities, particularly securities that are convertible into securities of an issuer other than the issuer of the convertible securities, may be illiquid.

Credit Risk - An issuer may default on its obligations to pay principal and/or interest. A security’s value may be affected by changes in its credit quality rating or its issuer’s financial conditions.

Currency Risk - Adverse fluctuations in exchange rates between the U.S. Dollar and other currencies may cause the Fund to lose money on investments denominated in foreign currencies.

Derivatives Risk - The Fund may invest in derivatives, including futures contracts on U.S. Treasury securities. Using derivatives can disproportionately increase losses and reduce opportunities for gains when stock prices, currency rates or interest rates are changing. The Fund may not fully benefit from or may lose money on derivatives if changes in their value do not correspond accurately to changes in the value of the Fund’s holdings. The other parties to certain derivative contracts present the same types of credit risk as issuers of fixed income securities. Derivatives can also make a fund less liquid and harder to value, especially in declining markets, and may increase the Fund’s volatility. There can be no assurance that the Fund’s use of derivative contracts will work as intended, and it is possible for the Fund to lose more than its original investment.

Foreign Securities Risk - Foreign markets can be more volatile than the U.S. market due to increased risks of adverse issuer, political, regulatory, market, currency valuation or economic developments. In addition, emerging markets may be more volatile and less liquid than the markets of more mature economies, and the securities of emerging markets issuers often are subject to rapid and large changes in price.

Geographic Concentration Risk - Geographic concentration risk is the risk that economic, political and social conditions in a single country, a limited number of countries or a particular geographic region in which the Fund is invested will have a significant impact on the performance of the Fund.

High Yield Securities Risk - Below investment grade (“high yield-high risk” or “junk”) bonds are speculative, have a higher degree of credit risk and interest rate risk, and may be less liquid and subject to greater volatility in market value than investment grade bonds.

Interest Rate Risk - The market value of a fixed income security is affected significantly by changes in interest rates. When interest rates rise, the market value of fixed income securities generally declines and when interest rates decline, market values of such securities generally rise. The longer a security’s maturity, that is, the time remaining until the final payment on the security is due, the greater the risk and the higher its yield. Conversely, the shorter a security’s maturity, the lower the risk and the lower its yield. In general, the longer the maturity or duration of a security, the greater its sensitivity to changes in interest rates. Recent and potential future changes in monetary policy may affect the level of interest rates.

Liquidity Risk - The fixed income securities in which the Fund invests may be less readily marketable and may be subject to greater fluctuation in price than other securities. When there is little or no active trading market for specific types of securities, legal or contractual restrictions on resale, or the reduced number and capacity of market participants to make a market in such security, it can become more difficult to sell the securities at or near their perceived value. In such a market, the value of such securities and the Fund’s share price may fall dramatically. Extraordinary and sudden changes in interest rates could disrupt the market for fixed-income securities and result in fluctuations in the Fund’s net asset value. Increased redemptions due to a rise in interest rates may require the Fund to liquidate its holdings at an unfavorable time and/or under adverse or disadvantageous conditions which may negatively affect the Fund. Investments in many, but not all, foreign securities tend to have greater exposure to liquidity risk than domestic securities.

Management Risk - A strategy used by the portfolio managers may fail to produce the intended results.

Market Risk - The market values of securities owned by the Fund will go up and down, sometimes rapidly or unpredictably. A security's market value may be reduced by market activity or other results of supply and demand unrelated to the issuer. This is a basic risk associated with all securities. When there are more sellers than buyers, prices tend to fall. Likewise, when there are more buyers than sellers, prices tend to rise.

Mortgage-Backed and Asset-Backed Securities Risk – Mortgage-backed and asset-backed securities are subject to interest rate risk and credit risk. These securities are also subject to the risk that borrowers will prepay the principal on their loans more quickly than expected (prepayment risk) or more slowly than expected (extension risk), which will affect the yield, average life and price of the securities. In addition, faster than expected prepayments may cause the Fund to invest the prepaid principal in lower yielding securities, and slower than expected prepayments may reduce the potential for the Fund to invest in higher yielding securities.

Mortgage Dollar Roll Risk - Mortgage dollar roll transactions involve the risk that the market value of the securities sold by the Fund may decline below the repurchase price of those securities. These transactions involve the risk that the portfolio managers will not correctly predict mortgage prepayments and interest rates, which will diminish the Fund’s performance. These transactions may increase the Fund’s portfolio turnover rate.

Multi-Manager Risk - The Adviser and Sub-Adviser make investment decisions independently. It is possible that the security selection process of the Adviser and Sub-Adviser may not complement one another and the Fund may have buy and sell transactions in the same security on the same day. The Adviser and Sub-Adviser selected may underperform the market generally or other advisers or sub-advisers that could have been selected.

U.S. Government Securities Risk – Yields available from U.S. Government securities are generally lower than yields from many other fixed income securities. U.S. Government securities may be adversely affected by changes in interest rates or a default by, or decline in the credit quality of, the U.S. Government.

U.S. Government-Sponsored Securities Risk - Securities issued by U.S. Government-sponsored enterprises (“GSEs”), such as the Federal Home Loan Mortgage Corporation, the Federal National Mortgage Association and the Federal Home Loan Banks, are not issued or guaranteed by the U.S. Treasury.

An investment in the Fund is not a deposit with a bank, is not insured, endorsed or guaranteed by the FDIC or any government agency, and is subject to the possible loss of your original investment.

Performance

No performance data is provided because the Fund had not commenced operations as of the date of this Prospectus. Performance information will appear in future versions of this Prospectus after the Fund has annual returns for at least one complete calendar year.

Updated performance information may be obtained at www.greatwestfunds.com (the website does not form a part of this Prospectus).

[1] Because the Fund has not yet commenced operations, "Other Expenses" are based on estimated amounts for the current fiscal year.

[2] Great-West Capital Management, LLC ("GWCM"), the Fund's investment adviser, has contractually agreed to waive fees or reimburse expenses that exceed 0.45% of the Fund's average daily net assets, excluding brokerage expenses, taxes, dividend interest on short sales, interest expenses, and any extraordinary expenses, including litigation costs (the "Expense Limit"). The agreement's current term ends on August 28, 2019 and automatically renews for one-year terms unless it is terminated by the Fund or GWCM upon written notice within 90 days of the end of the current term or upon termination of the investment advisory agreement between the Fund and GWCM. Under the agreement, GWCM may recoup, subject to Board approval, these waivers and reimbursements in future periods, not exceeding three years following the particular waiver/reimbursement, provided Total Annual Fund Operating Expenses plus such recoupment do not exceed the lesser of the Expense Limit that was in place at the time of the waiver/reimbursement or the Expense Limit in place at the time of recoupment.

XML

Label	Element	Value
Risk/Return:	rr_RiskReturnAbstract
Registrant Name	dei_EntityRegistrantName	GREAT-WEST FUNDS INC
Prospectus Date	rr_ProspectusDate	Jun. 25, 2018
Great-West Core Strategies: Flexible Bond Fund
Risk/Return:	rr_RiskReturnAbstract
Risk/Return [Heading]	rr_RiskReturnHeading	Fund Summary
Objective [Heading]	rr_ObjectiveHeading	Investment Objective
Objective, Primary [Text Block]	rr_ObjectivePrimaryTextBlock	The Fund seeks to provide total return, consisting of two components: (1) changes in the market value of its portfolio holdings (both realized and unrealized appreciation); and (2) income received from its portfolio holdings.
Expense [Heading]	rr_ExpenseHeading	Fees and Expenses of the Fund
Expense Narrative [Text Block]	rr_ExpenseNarrativeTextBlock	This table describes the fees and expenses that you may pay if you buy and hold shares of the Fund. In addition to the fees and expenses described below, you may be required to pay your financial professional brokerage commissions when you purchase or sell Institutional Class shares.
Shareholder Fees Caption [Text]	rr_ShareholderFeesCaption	Shareholder Fees (fees paid directly from your investment)
Operating Expenses Caption [Text]	rr_OperatingExpensesCaption	Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)
Fee Waiver or Reimbursement over Assets, Date of Termination	rr_FeeWaiverOrReimbursementOverAssetsDateOfTermination	August 28, 2019
Portfolio Turnover [Heading]	rr_PortfolioTurnoverHeading	Portfolio Turnover
Portfolio Turnover [Text Block]	rr_PortfolioTurnoverTextBlock	The Fund pays transaction costs, such as commissions, when it buys and sells securities (or “turns over” its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when Fund shares are held in a taxable account. These costs, which are not reflected in annual fund operating expenses or in the example, affect the Fund’s performance.
Other Expenses, New Fund, Based on Estimates [Text]	rr_OtherExpensesNewFundBasedOnEstimates	"Other Expenses" are based on estimated amounts for the current fiscal year.
Expense Example [Heading]	rr_ExpenseExampleHeading	Example
Expense Example Narrative [Text Block]	rr_ExpenseExampleNarrativeTextBlock	This Example is intended to help you compare the cost of investing in the Fund with the cost of investing in other mutual funds. The Example assumes that you invest $10,000 in the Fund for the time periods indicated and applies whether you hold or redeem all of your shares at the end of each period. The Example also assumes that the expense reimbursement is in place for the first year, that your investment has a 5% return each year, that all dividends and capital gains are reinvested, and that the Fund’s operating expenses are the amount shown in the fee table and remain the same for the years shown. Although your actual costs may be higher or lower, based on these assumptions, your costs would be:
Strategy [Heading]	rr_StrategyHeading	Principal Investment Strategies
Strategy Narrative [Text Block]	rr_StrategyNarrativeTextBlock	The following is a summary of the principal investment strategies of the Fund: The Fund will, under normal circumstances, invest at least 80% of its net assets (plus the amount of borrowings for investment purposes) in a diversified portfolio of fixed income securities. Fixed income securities include corporate bonds, securities that have been issued or guaranteed by the U.S. government or its agencies or instrumentalities (“U.S. Government Securities”), mortgage- and asset-backed securities, and bank loans. The Fund primarily invests in investment grade securities, and may invest in securities of any maturity and of any duration. The Fund may invest up to 20% of its total assets in preferred stock and convertible preferred stock. It may invest up to 20% of its total assets in foreign fixed income securities; however, fixed income securities of Canadian issuers and fixed income securities issued by supranational agencies (e.g., the World Bank) are not subject to this 20% limitation. It may also invest up to 35% of its total assets in securities of below investment grade quality (“high yield-high risk” or “junk”) bonds. The Fund may also enter into mortgage dollar rolls. In a mortgage dollar roll transaction, the Fund sells securities for delivery in the current month and simultaneously contracts to repurchase substantially similar securities (the same type, issuer, term and coupon) on a specified future date from the same party. For purposes of pursuing its investment goals, the Fund may, from time to time, enter into derivative contracts, including futures contracts on U.S. Treasury securities. The Fund’s investment portfolio is managed by GWCM and Loomis, Sayles & Company, L.P. (“Loomis Sayles” or “Sub-Adviser”) serves as a sub-adviser to a portion of the Fund’s assets. GWCM seeks to invest in U.S. Government Securities by employing a “top-down,” or global, macroeconomic analysis of the fixed income markets, setting strategic targets to guide discussions on interest rate sensitivity and sector allocations, and then pairing these targets with “bottom-up,” or security-by-security, fundamental research to make individual investment decisions and help manage risks within each bond sector. Loomis Sayles seeks to invest in fixed income securities by focusing on good relative value based on the credit outlook of the issuer and maximum total return potential. GWCM maintains a strategic allocation of the Fund’s assets with Loomis Sayles and reviews the asset allocations on a quarterly basis, or more frequently as deemed necessary. As of the date of this Prospectus, the target asset allocation is a 50% allocation of the Fund’s assets to each of GWCM and Loomis Sayles. Notwithstanding the target allocation, GWCM may change the asset allocations at any time and without shareholder notice or approval.
Risk [Heading]	rr_RiskHeading	Principal Investment Risks
Risk Narrative [Text Block]	rr_RiskNarrativeTextBlock	The following is a summary of the principal investment risks of investing in the Fund: Bank Loan Risk - Bank loans often involve borrowers whose financial conditions are troubled or uncertain and companies that are highly leveraged. The market for bank loans may not be highly liquid and the Fund may have difficulty selling bank loans. These investments expose the Fund to the credit risk of both the financial institution and the underlying borrower. Bank loans generally are subject to legal or contractual restrictions on resale. In addition, bank loans may have trade settlement periods extending beyond seven days. Bank loans may be structured such that they are not securities under securities laws and subject to securities laws protections against fraud and misrepresentation. As such, there can be no assurances that fraud or misrepresentation will not occur with respect to bank loans in which the Fund invests. Convertible Securities Risk - Convertible securities, particularly securities that are convertible into securities of an issuer other than the issuer of the convertible securities, may be illiquid. Credit Risk - An issuer may default on its obligations to pay principal and/or interest. A security’s value may be affected by changes in its credit quality rating or its issuer’s financial conditions. Currency Risk - Adverse fluctuations in exchange rates between the U.S. Dollar and other currencies may cause the Fund to lose money on investments denominated in foreign currencies. Derivatives Risk - The Fund may invest in derivatives, including futures contracts on U.S. Treasury securities. Using derivatives can disproportionately increase losses and reduce opportunities for gains when stock prices, currency rates or interest rates are changing. The Fund may not fully benefit from or may lose money on derivatives if changes in their value do not correspond accurately to changes in the value of the Fund’s holdings. The other parties to certain derivative contracts present the same types of credit risk as issuers of fixed income securities. Derivatives can also make a fund less liquid and harder to value, especially in declining markets, and may increase the Fund’s volatility. There can be no assurance that the Fund’s use of derivative contracts will work as intended, and it is possible for the Fund to lose more than its original investment. Foreign Securities Risk - Foreign markets can be more volatile than the U.S. market due to increased risks of adverse issuer, political, regulatory, market, currency valuation or economic developments. In addition, emerging markets may be more volatile and less liquid than the markets of more mature economies, and the securities of emerging markets issuers often are subject to rapid and large changes in price. Geographic Concentration Risk - Geographic concentration risk is the risk that economic, political and social conditions in a single country, a limited number of countries or a particular geographic region in which the Fund is invested will have a significant impact on the performance of the Fund. High Yield Securities Risk - Below investment grade (“high yield-high risk” or “junk”) bonds are speculative, have a higher degree of credit risk and interest rate risk, and may be less liquid and subject to greater volatility in market value than investment grade bonds. Interest Rate Risk - The market value of a fixed income security is affected significantly by changes in interest rates. When interest rates rise, the market value of fixed income securities generally declines and when interest rates decline, market values of such securities generally rise. The longer a security’s maturity, that is, the time remaining until the final payment on the security is due, the greater the risk and the higher its yield. Conversely, the shorter a security’s maturity, the lower the risk and the lower its yield. In general, the longer the maturity or duration of a security, the greater its sensitivity to changes in interest rates. Recent and potential future changes in monetary policy may affect the level of interest rates. Liquidity Risk - The fixed income securities in which the Fund invests may be less readily marketable and may be subject to greater fluctuation in price than other securities. When there is little or no active trading market for specific types of securities, legal or contractual restrictions on resale, or the reduced number and capacity of market participants to make a market in such security, it can become more difficult to sell the securities at or near their perceived value. In such a market, the value of such securities and the Fund’s share price may fall dramatically. Extraordinary and sudden changes in interest rates could disrupt the market for fixed-income securities and result in fluctuations in the Fund’s net asset value. Increased redemptions due to a rise in interest rates may require the Fund to liquidate its holdings at an unfavorable time and/or under adverse or disadvantageous conditions which may negatively affect the Fund. Investments in many, but not all, foreign securities tend to have greater exposure to liquidity risk than domestic securities. Management Risk - A strategy used by the portfolio managers may fail to produce the intended results. Market Risk - The market values of securities owned by the Fund will go up and down, sometimes rapidly or unpredictably. A security's market value may be reduced by market activity or other results of supply and demand unrelated to the issuer. This is a basic risk associated with all securities. When there are more sellers than buyers, prices tend to fall. Likewise, when there are more buyers than sellers, prices tend to rise. Mortgage-Backed and Asset-Backed Securities Risk – Mortgage-backed and asset-backed securities are subject to interest rate risk and credit risk. These securities are also subject to the risk that borrowers will prepay the principal on their loans more quickly than expected (prepayment risk) or more slowly than expected (extension risk), which will affect the yield, average life and price of the securities. In addition, faster than expected prepayments may cause the Fund to invest the prepaid principal in lower yielding securities, and slower than expected prepayments may reduce the potential for the Fund to invest in higher yielding securities. Mortgage Dollar Roll Risk - Mortgage dollar roll transactions involve the risk that the market value of the securities sold by the Fund may decline below the repurchase price of those securities. These transactions involve the risk that the portfolio managers will not correctly predict mortgage prepayments and interest rates, which will diminish the Fund’s performance. These transactions may increase the Fund’s portfolio turnover rate. Multi-Manager Risk - The Adviser and Sub-Adviser make investment decisions independently. It is possible that the security selection process of the Adviser and Sub-Adviser may not complement one another and the Fund may have buy and sell transactions in the same security on the same day. The Adviser and Sub-Adviser selected may underperform the market generally or other advisers or sub-advisers that could have been selected. U.S. Government Securities Risk – Yields available from U.S. Government securities are generally lower than yields from many other fixed income securities. U.S. Government securities may be adversely affected by changes in interest rates or a default by, or decline in the credit quality of, the U.S. Government. U.S. Government-Sponsored Securities Risk - Securities issued by U.S. Government-sponsored enterprises (“GSEs”), such as the Federal Home Loan Mortgage Corporation, the Federal National Mortgage Association and the Federal Home Loan Banks, are not issued or guaranteed by the U.S. Treasury. An investment in the Fund is not a deposit with a bank, is not insured, endorsed or guaranteed by the FDIC or any government agency, and is subject to the possible loss of your original investment.
Risk Lose Money [Text]	rr_RiskLoseMoney	is subject to the possible loss of your original investment.
Risk Not Insured Depository Institution [Text]	rr_RiskNotInsuredDepositoryInstitution	An investment in the Fund is not a deposit with a bank, is not insured, endorsed or guaranteed by the FDIC or any government agency,
Bar Chart and Performance Table [Heading]	rr_BarChartAndPerformanceTableHeading	Performance
Performance Narrative [Text Block]	rr_PerformanceNarrativeTextBlock	No performance data is provided because the Fund had not commenced operations as of the date of this Prospectus. Performance information will appear in future versions of this Prospectus after the Fund has annual returns for at least one complete calendar year. Updated performance information may be obtained at www.greatwestfunds.com (the website does not form a part of this Prospectus).
Performance One Year or Less [Text]	rr_PerformanceOneYearOrLess	No performance data is provided because the Fund had not commenced operations as of the date of this Prospectus.
Performance Availability Website Address [Text]	rr_PerformanceAvailabilityWebSiteAddress	www.greatwestfunds.com
Great-West Core Strategies: Flexible Bond Fund | Institutional Class
Risk/Return:	rr_RiskReturnAbstract
Maximum Sales Charge (Load) Imposed on Purchases (as a percentage of offering price)	rr_MaximumSalesChargeImposedOnPurchasesOverOfferingPrice	none
Maximum Deferred Sales Charge (Load)	rr_MaximumDeferredSalesChargeOverOther	none
Maximum Sales Charge (Load) Imposed on Reinvested Dividends	rr_MaximumSalesChargeOnReinvestedDividendsAndDistributionsOverOther	none
Redemption Fee	rr_RedemptionFeeOverRedemption	none
Exchange Fee	rr_ExchangeFeeOverRedemption	none
Management Fees	rr_ManagementFeesOverAssets	0.38%	[1]
Distribution and Service (12b-1) Fees	rr_DistributionAndService12b1FeesOverAssets	none	[1]
Other Expenses	rr_OtherExpensesOverAssets	0.37%	[1]
Total Annual Fund Operating Expenses	rr_ExpensesOverAssets	0.75%	[1]
Fee Waiver and Expense Reimbursement	rr_FeeWaiverOrReimbursementOverAssets	0.30%	[1],[2]
Total Annual Fund Operating Expenses After Fee Waiver and Expense Reimbursement	rr_NetExpensesOverAssets	0.45%	[1]
1 Year	rr_ExpenseExampleYear01	$ 46
3 Years	rr_ExpenseExampleYear03	$ 209

[1] Because the Fund has not yet commenced operations, "Other Expenses" are based on estimated amounts for the current fiscal year.

[2] Great-West Capital Management, LLC ("GWCM"), the Fund's investment adviser, has contractually agreed to waive fees or reimburse expenses that exceed 0.45% of the Fund's average daily net assets, excluding brokerage expenses, taxes, dividend interest on short sales, interest expenses, and any extraordinary expenses, including litigation costs (the "Expense Limit"). The agreement's current term ends on August 28, 2019 and automatically renews for one-year terms unless it is terminated by the Fund or GWCM upon written notice within 90 days of the end of the current term or upon termination of the investment advisory agreement between the Fund and GWCM. Under the agreement, GWCM may recoup, subject to Board approval, these waivers and reimbursements in future periods, not exceeding three years following the particular waiver/reimbursement, provided Total Annual Fund Operating Expenses plus such recoupment do not exceed the lesser of the Expense Limit that was in place at the time of the waiver/reimbursement or the Expense Limit in place at the time of recoupment.

XML

Great-West Core Strategies: Inflation-Protected Securities Fund

Fund Summary

Investment Objective

The Fund seeks real return consistent with the preservation of capital.

Fees and Expenses of the Fund

This table describes the fees and expenses that you may pay if you buy and hold shares of the Fund. In addition to the fees and expenses described below, you may be required to pay your financial professional brokerage commissions when you purchase or sell Institutional Class shares.

Shareholder Fees (fees paid directly from your investment)

Shareholder Fees	Great-West Core Strategies: Inflation-Protected Securities Fund Institutional Class
Maximum Sales Charge (Load) Imposed on Purchases (as a percentage of offering price)	none
Maximum Deferred Sales Charge (Load)	none
Maximum Sales Charge (Load) Imposed on Reinvested Dividends	none
Redemption Fee	none
Exchange Fee	none

Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)

Annual Fund Operating Expenses	Great-West Core Strategies: Inflation-Protected Securities Fund Institutional Class
Management Fees	0.33%
Distribution and Service (12b-1) Fees	none
Other Expenses	0.92%	[1]
Total Annual Fund Operating Expenses	1.25%
Fee Waiver and Expense Reimbursement	0.85%	[2]
Total Annual Fund Operating Expenses After Fee Waiver and Expense Reimbursement	0.40%

Example

This Example is intended to help you compare the cost of investing in the Fund with the cost of investing in other mutual funds.

The Example assumes that you invest $10,000 in the Fund for the time periods indicated and applies whether you hold or redeem all of your shares at the end of each period. The Example also assumes that the expense reimbursement is in place for the first year, that your investment has a 5% return each year, that all dividends and capital gains are reinvested, and that the Fund’s operating expenses are the amount shown in the fee table and remain the same for the years shown. Although your actual costs may be higher or lower, based on these assumptions, your costs would be:

Expense Example	1 Year	3 Years
Great-West Core Strategies: Inflation-Protected Securities Fund | Institutional Class | USD ($)	41	313

Portfolio Turnover

The Fund pays transaction costs, such as commissions, when it buys and sells securities (or “turns over” its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when Fund shares are held in a taxable account. These costs, which are not reflected in annual fund operating expenses or in the example, affect the Fund’s performance.

Principal Investment Strategies

The Fund will, under normal circumstances, invest at least 80% of its net assets (plus the amount of any borrowings for investment purposes) in inflation-protected securities (“IPS”) of varying maturities issued by the U.S. Treasury (“TIPS”) and other U.S. and non-U.S. Government agencies and corporations (“CIPS”), and other instruments, including inflation-linked swaps, with similar economic characteristics. IPS are designed to provide inflation-protection to investors. The U.S. Treasury uses the Consumer Price Index for Urban Consumers (the “CPI-U”) as the measurement of inflation, while other issuers of IPS may use other indices as the measure of inflation. IPS are income-generating instruments whose interest and principal payments are adjusted for inflation, that is, a sustained increase in prices that erodes the purchasing power of money. The inflation adjustment, which is typically applied monthly to the principal of a bond, follows a designated inflation index, such as the CPI-U. A fixed coupon rate is applied to the inflation-adjusted principal so that as inflation rises, both the principal value and the interest payments increase. This can provide investors with a hedge against inflation, as it helps preserve the purchasing power of an investment. Because of this inflation adjustment feature, inflation-protected bonds typically have lower yields than conventional fixed-rate bonds.

The Fund intends to invest in derivatives, including exchange-traded futures and inflation-linked swaps, primarily to hedge the Fund’s portfolio risks, manage the Fund’s duration, and/or gain exposure to inflation and certain fixed income securities. The Fund expects to invest in inflation-linked swaps that reference the CPI-U, as well as other measures of inflation.

The remainder of the Fund’s assets may be invested in other fixed income securities, including securities issued or guaranteed by the U.S. Government, its agencies, instrumentalities or sponsored enterprises (“U.S. Government Securities”), asset-backed securities, mortgage-backed securities, corporate securities, below investment grade fixed income securities and securities issued by foreign corporate and governmental issuers.

“Duration” is a measure of a debt security’s price sensitivity to changes in interest rates. The longer the duration of the Fund (or an individual debt security), the more sensitive its market price will be to changes in interest rates. For example, if market interest rates increase by 1%, the market price of a debt security with a three-year effective duration will generally decrease by approximately 3%. Conversely, a 1% decline in market interest rates will generally result in an increase of approximately 3% of that security’s market price. The Fund’s target duration range under normal interest rate conditions is expected to approximate that of its benchmark index, the Bloomberg Barclays 1-10 Year U.S. Treasury Inflation-Protected Securities (TIPS) Index, plus or minus one year. As of December 31, 2017, the duration of this index was 5.15 years.

Principal Investment Risks

The following is a summary of the principal investment risks of investing in the Fund:

Counterparty Risk - A counterparty may default on its obligations to pay principal and/or interest. To the extent that a counterparty defaults on its obligations and the Fund is delayed or prevented from exercising its rights with respect to the investments in its portfolio, it may experience a decline in the value of its position, lose income and incur costs associated with asserting its rights.

CPI-U Measurement Risk – There can be no assurance that the CPI-U, a measurement of changes in the cost of living, will accurately measure the real rate of inflation in the prices of goods and services, which may affect the valuation of the Fund.

Credit Risk - An issuer may default on its obligations to pay principal and/or interest. A security’s value may be affected by changes in its credit quality rating or its issuer’s financial conditions.

Deflation Risk – If deflation occurs, the principal and income of IPS held by the Fund would likely decline in price, which could result in losses for the Fund.

Derivatives Risk - The Fund may invest in derivative instruments, including exchange-traded futures and inflation-linked swaps. Using derivatives can disproportionately increase losses and reduce opportunities for gains when security prices, currency rates, inflation rates or interest rates are changing. The Fund may not fully benefit from or may lose money on derivatives if changes in their value do not correspond accurately to changes in the value of the Fund’s holdings. The other parties to certain derivative contracts present the same types of credit risk as issuers of fixed income securities. Derivatives can also make a fund less liquid and harder to value, especially in declining markets and may increase the Fund’s volatility. There can be no assurance that the Fund’s use of derivative contracts will work as intended, and it is possible for the Fund to lose more than its original investment.

Foreign Securities Risk - Foreign markets can be more volatile than the U.S. market due to increased risks of adverse issuer, political, regulatory, market, currency valuation or economic developments.

Foreign Government Securities Risk - Foreign government securities may involve risks similar to those of foreign securities. They also may present additional risks, such as the ability of a foreign government or government-related issuer to make timely principal and interest payments on its external debt obligations.

High Yield Securities Risk - Below investment grade (“high yield-high risk” or “junk”) bonds are speculative, have a higher degree of credit risk and interest rate risk, and may be less liquid and subject to greater volatility in market value than investment grade bonds.

Inflation-linked Swaps Risk - Inflation-linked swaps may expose the Fund to additional volatility, can be illiquid and difficult to value, and may involve leverage so that small changes produce disproportionate losses for the Fund. In addition, since inflation-linked swaps are not traded on an exchange, they are subject to the risk that a counterparty to a transaction will fail to meet its obligations. Inflation-linked swaps involve the risk that the level of inflation and consumer prices will not be accurately predicted, which could significantly harm the Fund’s performance.

IPS Risk - The value of IPS generally fluctuates in response to changes in real interest rates, which are in turn tied to the relationship between nominal interest rates and the rate of inflation. If nominal interest rates increased at a faster rate than inflation, real interest rates might rise, leading to a decrease in the value of IPS. The market for IPS may be less developed or liquid, and more volatile, than certain other securities markets.

Interest Rate Risk - The market value of a fixed income security is affected significantly by changes in interest rates. When interest rates rise, the market value of fixed income securities generally declines and when interest rates decline, market values of such securities generally rise. The longer a security’s maturity, that is, the time remaining until the final payment on the security is due, the greater the risk and the higher its yield. Conversely, the shorter a security’s maturity, the lower the risk and the lower its yield. In general, the longer the maturity or duration of a security, the greater its sensitivity to changes in interest rates. Recent and potential future changes in monetary policy may affect the level of interest rates.

Management Risk - A strategy used by the portfolio managers may fail to produce the intended results.

Market Risk - The market values of securities owned by the Fund will go up and down, sometimes rapidly or unpredictably. A security's market value may be reduced by market activity or other results of supply and demand unrelated to the issuer. This is a basic risk associated with all securities. When there are more sellers than buyers, prices tend to fall. Likewise, when there are more buyers than sellers, prices tend to rise.

Mortgage-Backed and Asset-Backed Securities Risk – Mortgage-backed and asset-backed securities are subject to interest rate risk and credit risk. These securities are also subject to the risk that borrowers will prepay the principal on their loans more quickly than expected (prepayment risk) or more slowly than expected (extension risk), which will affect the yield, average life and price of the securities. In addition, faster than expected prepayments may cause the Fund to invest the prepaid principal in lower yielding securities, and slower than expected prepayments may reduce the potential for the Fund to invest in higher yielding securities.

Tax Consequences Risk - The Fund will be subject to the risk that adjustments for inflation to the principal amount of an inflation-indexed bond may give rise to original issue discount, which will be includable in the Fund’s gross income.

U.S. Government Securities Risk – U.S. Government securities may be adversely affected by changes in interest rates or a default by, or decline in the credit quality of, the U.S. Government.

U.S. Government-Sponsored Securities Risk - Securities issued by U.S. Government-sponsored enterprises (“GSEs”), such as the Federal Home Loan Mortgage Corporation, the Federal National Mortgage Association and the Federal Home Loan Banks, are not issued or guaranteed by the U.S. Treasury.

An investment in the Fund is not a deposit with a bank, is not insured, endorsed or guaranteed by the FDIC or any government agency, and is subject to the possible loss of your original investment.

Performance

No performance data is provided because the Fund had not commenced operations as of the date of this Prospectus. Performance information will appear in future versions of this Prospectus after the Fund has annual returns for at least one complete calendar year.

Updated performance information may be obtained at www.greatwestfunds.com (the website does not form a part of this Prospectus).

[1] Because the Fund has not yet commenced operations, “Other Expenses” are based on estimated amounts for the current fiscal year.

[2] Great-West Capital Management, LLC (“GWCM”), the Fund's investment adviser, has contractually agreed to waive fees or reimburse expenses that exceed 0.40% of the Fund's average daily net assets, excluding brokerage expenses, taxes, dividend interest on short sales, interest expenses, and any extraordinary expenses, including litigation costs (the “Expense Limit”). The agreement's current term ends on August 28, 2019 and automatically renews for one-year terms unless it is terminated by the Fund or GWCM upon written notice within 90 days of the end of the current term or upon termination of the investment advisory agreement between the Fund and GWCM. Under the agreement, GWCM may recoup, subject to Board approval, these waivers and reimbursements in future periods, not exceeding three years following the particular waiver/reimbursement, provided Total Annual Fund Operating Expenses plus such recoupment do not exceed the lesser of the Expense Limit that was in place at the time of the waiver/reimbursement or the Expense Limit in place at the time of recoupment.

XML

Label	Element	Value
Risk/Return:	rr_RiskReturnAbstract
Registrant Name	dei_EntityRegistrantName	GREAT-WEST FUNDS INC
Prospectus Date	rr_ProspectusDate	Jun. 25, 2018
Great-West Core Strategies: Inflation-Protected Securities Fund
Risk/Return:	rr_RiskReturnAbstract
Risk/Return [Heading]	rr_RiskReturnHeading	Fund Summary
Objective [Heading]	rr_ObjectiveHeading	Investment Objective
Objective, Primary [Text Block]	rr_ObjectivePrimaryTextBlock	The Fund seeks real return consistent with the preservation of capital.
Expense [Heading]	rr_ExpenseHeading	Fees and Expenses of the Fund
Expense Narrative [Text Block]	rr_ExpenseNarrativeTextBlock	This table describes the fees and expenses that you may pay if you buy and hold shares of the Fund. In addition to the fees and expenses described below, you may be required to pay your financial professional brokerage commissions when you purchase or sell Institutional Class shares.
Shareholder Fees Caption [Text]	rr_ShareholderFeesCaption	Shareholder Fees (fees paid directly from your investment)
Operating Expenses Caption [Text]	rr_OperatingExpensesCaption	Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)
Fee Waiver or Reimbursement over Assets, Date of Termination	rr_FeeWaiverOrReimbursementOverAssetsDateOfTermination	August 28, 2019
Portfolio Turnover [Heading]	rr_PortfolioTurnoverHeading	Portfolio Turnover
Portfolio Turnover [Text Block]	rr_PortfolioTurnoverTextBlock	The Fund pays transaction costs, such as commissions, when it buys and sells securities (or “turns over” its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when Fund shares are held in a taxable account. These costs, which are not reflected in annual fund operating expenses or in the example, affect the Fund’s performance.
Other Expenses, New Fund, Based on Estimates [Text]	rr_OtherExpensesNewFundBasedOnEstimates	"Other Expenses" are based on estimated amounts for the current fiscal year.
Expense Example [Heading]	rr_ExpenseExampleHeading	Example
Expense Example Narrative [Text Block]	rr_ExpenseExampleNarrativeTextBlock	This Example is intended to help you compare the cost of investing in the Fund with the cost of investing in other mutual funds. The Example assumes that you invest $10,000 in the Fund for the time periods indicated and applies whether you hold or redeem all of your shares at the end of each period. The Example also assumes that the expense reimbursement is in place for the first year, that your investment has a 5% return each year, that all dividends and capital gains are reinvested, and that the Fund’s operating expenses are the amount shown in the fee table and remain the same for the years shown. Although your actual costs may be higher or lower, based on these assumptions, your costs would be:
Strategy [Heading]	rr_StrategyHeading	Principal Investment Strategies
Strategy Narrative [Text Block]	rr_StrategyNarrativeTextBlock	The Fund will, under normal circumstances, invest at least 80% of its net assets (plus the amount of any borrowings for investment purposes) in inflation-protected securities (“IPS”) of varying maturities issued by the U.S. Treasury (“TIPS”) and other U.S. and non-U.S. Government agencies and corporations (“CIPS”), and other instruments, including inflation-linked swaps, with similar economic characteristics. IPS are designed to provide inflation-protection to investors. The U.S. Treasury uses the Consumer Price Index for Urban Consumers (the “CPI-U”) as the measurement of inflation, while other issuers of IPS may use other indices as the measure of inflation. IPS are income-generating instruments whose interest and principal payments are adjusted for inflation, that is, a sustained increase in prices that erodes the purchasing power of money. The inflation adjustment, which is typically applied monthly to the principal of a bond, follows a designated inflation index, such as the CPI-U. A fixed coupon rate is applied to the inflation-adjusted principal so that as inflation rises, both the principal value and the interest payments increase. This can provide investors with a hedge against inflation, as it helps preserve the purchasing power of an investment. Because of this inflation adjustment feature, inflation-protected bonds typically have lower yields than conventional fixed-rate bonds. The Fund intends to invest in derivatives, including exchange-traded futures and inflation-linked swaps, primarily to hedge the Fund’s portfolio risks, manage the Fund’s duration, and/or gain exposure to inflation and certain fixed income securities. The Fund expects to invest in inflation-linked swaps that reference the CPI-U, as well as other measures of inflation. The remainder of the Fund’s assets may be invested in other fixed income securities, including securities issued or guaranteed by the U.S. Government, its agencies, instrumentalities or sponsored enterprises (“U.S. Government Securities”), asset-backed securities, mortgage-backed securities, corporate securities, below investment grade fixed income securities and securities issued by foreign corporate and governmental issuers. “Duration” is a measure of a debt security’s price sensitivity to changes in interest rates. The longer the duration of the Fund (or an individual debt security), the more sensitive its market price will be to changes in interest rates. For example, if market interest rates increase by 1%, the market price of a debt security with a three-year effective duration will generally decrease by approximately 3%. Conversely, a 1% decline in market interest rates will generally result in an increase of approximately 3% of that security’s market price. The Fund’s target duration range under normal interest rate conditions is expected to approximate that of its benchmark index, the Bloomberg Barclays 1-10 Year U.S. Treasury Inflation-Protected Securities (TIPS) Index, plus or minus one year. As of December 31, 2017, the duration of this index was 5.15 years.
Risk [Heading]	rr_RiskHeading	Principal Investment Risks
Risk Narrative [Text Block]	rr_RiskNarrativeTextBlock	The following is a summary of the principal investment risks of investing in the Fund: Counterparty Risk - A counterparty may default on its obligations to pay principal and/or interest. To the extent that a counterparty defaults on its obligations and the Fund is delayed or prevented from exercising its rights with respect to the investments in its portfolio, it may experience a decline in the value of its position, lose income and incur costs associated with asserting its rights. CPI-U Measurement Risk – There can be no assurance that the CPI-U, a measurement of changes in the cost of living, will accurately measure the real rate of inflation in the prices of goods and services, which may affect the valuation of the Fund. Credit Risk - An issuer may default on its obligations to pay principal and/or interest. A security’s value may be affected by changes in its credit quality rating or its issuer’s financial conditions. Deflation Risk – If deflation occurs, the principal and income of IPS held by the Fund would likely decline in price, which could result in losses for the Fund. Derivatives Risk - The Fund may invest in derivative instruments, including exchange-traded futures and inflation-linked swaps. Using derivatives can disproportionately increase losses and reduce opportunities for gains when security prices, currency rates, inflation rates or interest rates are changing. The Fund may not fully benefit from or may lose money on derivatives if changes in their value do not correspond accurately to changes in the value of the Fund’s holdings. The other parties to certain derivative contracts present the same types of credit risk as issuers of fixed income securities. Derivatives can also make a fund less liquid and harder to value, especially in declining markets and may increase the Fund’s volatility. There can be no assurance that the Fund’s use of derivative contracts will work as intended, and it is possible for the Fund to lose more than its original investment. Foreign Securities Risk - Foreign markets can be more volatile than the U.S. market due to increased risks of adverse issuer, political, regulatory, market, currency valuation or economic developments. Foreign Government Securities Risk - Foreign government securities may involve risks similar to those of foreign securities. They also may present additional risks, such as the ability of a foreign government or government-related issuer to make timely principal and interest payments on its external debt obligations. High Yield Securities Risk - Below investment grade (“high yield-high risk” or “junk”) bonds are speculative, have a higher degree of credit risk and interest rate risk, and may be less liquid and subject to greater volatility in market value than investment grade bonds. Inflation-linked Swaps Risk - Inflation-linked swaps may expose the Fund to additional volatility, can be illiquid and difficult to value, and may involve leverage so that small changes produce disproportionate losses for the Fund. In addition, since inflation-linked swaps are not traded on an exchange, they are subject to the risk that a counterparty to a transaction will fail to meet its obligations. Inflation-linked swaps involve the risk that the level of inflation and consumer prices will not be accurately predicted, which could significantly harm the Fund’s performance. IPS Risk - The value of IPS generally fluctuates in response to changes in real interest rates, which are in turn tied to the relationship between nominal interest rates and the rate of inflation. If nominal interest rates increased at a faster rate than inflation, real interest rates might rise, leading to a decrease in the value of IPS. The market for IPS may be less developed or liquid, and more volatile, than certain other securities markets. Interest Rate Risk - The market value of a fixed income security is affected significantly by changes in interest rates. When interest rates rise, the market value of fixed income securities generally declines and when interest rates decline, market values of such securities generally rise. The longer a security’s maturity, that is, the time remaining until the final payment on the security is due, the greater the risk and the higher its yield. Conversely, the shorter a security’s maturity, the lower the risk and the lower its yield. In general, the longer the maturity or duration of a security, the greater its sensitivity to changes in interest rates. Recent and potential future changes in monetary policy may affect the level of interest rates. Management Risk - A strategy used by the portfolio managers may fail to produce the intended results. Market Risk - The market values of securities owned by the Fund will go up and down, sometimes rapidly or unpredictably. A security's market value may be reduced by market activity or other results of supply and demand unrelated to the issuer. This is a basic risk associated with all securities. When there are more sellers than buyers, prices tend to fall. Likewise, when there are more buyers than sellers, prices tend to rise. Mortgage-Backed and Asset-Backed Securities Risk – Mortgage-backed and asset-backed securities are subject to interest rate risk and credit risk. These securities are also subject to the risk that borrowers will prepay the principal on their loans more quickly than expected (prepayment risk) or more slowly than expected (extension risk), which will affect the yield, average life and price of the securities. In addition, faster than expected prepayments may cause the Fund to invest the prepaid principal in lower yielding securities, and slower than expected prepayments may reduce the potential for the Fund to invest in higher yielding securities. Tax Consequences Risk - The Fund will be subject to the risk that adjustments for inflation to the principal amount of an inflation-indexed bond may give rise to original issue discount, which will be includable in the Fund’s gross income. U.S. Government Securities Risk – U.S. Government securities may be adversely affected by changes in interest rates or a default by, or decline in the credit quality of, the U.S. Government. U.S. Government-Sponsored Securities Risk - Securities issued by U.S. Government-sponsored enterprises (“GSEs”), such as the Federal Home Loan Mortgage Corporation, the Federal National Mortgage Association and the Federal Home Loan Banks, are not issued or guaranteed by the U.S. Treasury. An investment in the Fund is not a deposit with a bank, is not insured, endorsed or guaranteed by the FDIC or any government agency, and is subject to the possible loss of your original investment.
Risk Lose Money [Text]	rr_RiskLoseMoney	is subject to the possible loss of your original investment.
Risk Not Insured Depository Institution [Text]	rr_RiskNotInsuredDepositoryInstitution	An investment in the Fund is not a deposit with a bank, is not insured, endorsed or guaranteed by the FDIC or any government agency,
Bar Chart and Performance Table [Heading]	rr_BarChartAndPerformanceTableHeading	Performance
Performance Narrative [Text Block]	rr_PerformanceNarrativeTextBlock	No performance data is provided because the Fund had not commenced operations as of the date of this Prospectus. Performance information will appear in future versions of this Prospectus after the Fund has annual returns for at least one complete calendar year. Updated performance information may be obtained at www.greatwestfunds.com (the website does not form a part of this Prospectus).
Performance One Year or Less [Text]	rr_PerformanceOneYearOrLess	No performance data is provided because the Fund had not commenced operations as of the date of this Prospectus.
Performance Availability Website Address [Text]	rr_PerformanceAvailabilityWebSiteAddress	www.greatwestfunds.com
Great-West Core Strategies: Inflation-Protected Securities Fund | Institutional Class
Risk/Return:	rr_RiskReturnAbstract
Maximum Sales Charge (Load) Imposed on Purchases (as a percentage of offering price)	rr_MaximumSalesChargeImposedOnPurchasesOverOfferingPrice	none
Maximum Deferred Sales Charge (Load)	rr_MaximumDeferredSalesChargeOverOther	none
Maximum Sales Charge (Load) Imposed on Reinvested Dividends	rr_MaximumSalesChargeOnReinvestedDividendsAndDistributionsOverOther	none
Redemption Fee	rr_RedemptionFeeOverRedemption	none
Exchange Fee	rr_ExchangeFeeOverRedemption	none
Management Fees	rr_ManagementFeesOverAssets	0.33%
Distribution and Service (12b-1) Fees	rr_DistributionAndService12b1FeesOverAssets	none
Other Expenses	rr_OtherExpensesOverAssets	0.92%	[1]
Total Annual Fund Operating Expenses	rr_ExpensesOverAssets	1.25%
Fee Waiver and Expense Reimbursement	rr_FeeWaiverOrReimbursementOverAssets	0.85%	[2]
Total Annual Fund Operating Expenses After Fee Waiver and Expense Reimbursement	rr_NetExpensesOverAssets	0.40%
1 Year	rr_ExpenseExampleYear01	$ 41
3 Years	rr_ExpenseExampleYear03	$ 313

[1] Because the Fund has not yet commenced operations, “Other Expenses” are based on estimated amounts for the current fiscal year.

[2] Great-West Capital Management, LLC (“GWCM”), the Fund's investment adviser, has contractually agreed to waive fees or reimburse expenses that exceed 0.40% of the Fund's average daily net assets, excluding brokerage expenses, taxes, dividend interest on short sales, interest expenses, and any extraordinary expenses, including litigation costs (the “Expense Limit”). The agreement's current term ends on August 28, 2019 and automatically renews for one-year terms unless it is terminated by the Fund or GWCM upon written notice within 90 days of the end of the current term or upon termination of the investment advisory agreement between the Fund and GWCM. Under the agreement, GWCM may recoup, subject to Board approval, these waivers and reimbursements in future periods, not exceeding three years following the particular waiver/reimbursement, provided Total Annual Fund Operating Expenses plus such recoupment do not exceed the lesser of the Expense Limit that was in place at the time of the waiver/reimbursement or the Expense Limit in place at the time of recoupment.

XML

Great-West Core Strategies: International Equity Fund

Fund Summary

Investment Objective

The Fund seeks long-term growth of capital.

Fees and Expenses of the Fund

This table describes the fees and expenses that you may pay if you buy and hold shares of the Fund. In addition to the fees and expenses described below, you may be required to pay your financial professional brokerage commissions when you purchase or sell Institutional Class shares.

Shareholder Fees (fees paid directly from your investment)

Shareholder Fees	Great-West Core Strategies: International Equity Fund Institutional Class
Maximum Sales Charge (Load) Imposed on Purchases (as a percentage of offering price)	none
Maximum Deferred Sales Charge (Load)	none
Maximum Sales Charge (Load) Imposed on Reinvested Dividends	none
Redemption Fee	none
Exchange Fee	none

Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)

Annual Fund Operating Expenses	Great-West Core Strategies: International Equity Fund Institutional Class	[1]
Management Fees	0.53%
Distribution and Service (12b-1) Fees	none
Other Expenses	0.66%
Acquired Fund Fees and Expenses	0.01%
Total Annual Fund Operating Expenses	1.20%
Fee Waiver and Expense Reimbursement	0.54%	[2]
Total Annual Fund Operating Expenses After Fee Waiver and Expense Reimbursement	0.66%

Example

This Example is intended to help you compare the cost of investing in the Fund with the cost of investing in other mutual funds.

The Example assumes that you invest $10,000 in the Fund for the time periods indicated and applies whether you hold or redeem all of your shares at the end of each period. The Example also assumes that the expense reimbursement is in place for the first year, that your investment has a 5% return each year, that all dividends and capital gains are reinvested, and that the Fund’s operating expenses are the amount shown in the fee table and remain the same for the years shown. Although your actual costs may be higher or lower, based on these assumptions, your costs would be:

Expense Example	1 Year	3 Years
Great-West Core Strategies: International Equity Fund | Institutional Class | USD ($)	68	328

Portfolio Turnover

The Fund pays transaction costs, such as commissions, when it buys and sells securities (or “turns over” its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when Fund shares are held in a taxable account. These costs, which are not reflected in annual fund operating expenses or in the example, affect the Fund’s performance.

Principal Investment Strategies

The Fund will, under normal circumstances, invest at least 80% of its net assets (plus the amount of any borrowings for investment purposes) in equity securities of issuers economically tied to countries other than the U.S., including those in emerging markets. Equity securities may be represented by other investment instruments, including depositary receipts, derivatives, and exchange-traded funds that track the return of a broadly-based international securities index. Derivatives instruments include futures, forward contracts, options, structured securities, and swaps. The Fund may from time to time, have significant investments in a particular sector or country, a small number of countries, or a particular geographic region; provided that the Fund will, under normal circumstances, invest in at least three different countries. The Fund may have exposure to non-U.S. stocks across any market capitalization and style and the Fund’s exposure will vary from time to time across sectors.

The issuer of a security or other investment is generally deemed to be economically tied to a particular country other than the U.S. if: the security or other investment is issued or guaranteed by the government of that country or any of its agencies, authorities or instrumentalities; the issuer is organized under the laws of that country; the issuer maintains a principal office in that country; the issuer has its principal securities trading market in that country; the issuer derives 50% or more of its total revenues from goods sold or services performed in that country; the issuer has 50% or more of its assets in that country; or the issuer is included in an index which is representative of that country.

The Fund’s investment portfolio is managed by three sub-advisers: Franklin Templeton Institutional, LLC (“Franklin Templeton”), Irish Life Investment Managers Limited (“ILIM”), and LSV Asset Management (“LSV”) (each, a Sub-Adviser,“ and collectively, the ”Sub-Advisers“). Franklin Templeton employs a disciplined, bottom-up investment approach to identify attractive investment opportunities that have higher expected revenue and earnings growth than their peers. ILIM seeks to invest in equity securities contained in the MSCI EAFE Index in as close as possible a proportion as each stock’s weight in the MSCI EAFE Index. LSV employs a deep-value strategy that seeks to invest in undervalued international companies with high potential for near-term price appreciation.

GWCM maintains a strategic asset allocation of the Fund’s assets with each Sub-Adviser and reviews the asset allocations on a quarterly basis, or more frequently as deemed necessary. As of the date of this Prospectus, the target asset allocation is a 15% allocation of the Fund’s assets to Franklin Templeton, a 50% allocation of the Fund’s assets to ILIM, and a 35% allocation of the Fund’s assets to LSV. Notwithstanding these target allocations, initial allocations may vary from the target allocation and GWCM may change the asset allocations at any time and without shareholder notice or approval.

Principal Investment Risks

The following is a summary of the principal investment risks of investing in the Fund:

Currency Risk - Adverse fluctuations in exchange rates between the U.S. Dollar and other currencies may cause the Fund to lose money on investments denominated in foreign currencies.

Depositary Receipts Risk - Depositary receipts are generally subject to the same sort of risks as direct investments in a foreign country, such as, currency risk, political and economic risk, and market risk, because their values depend on the performance of a foreign security denominated in its home currency.

Derivatives Risk - The Fund may invest in derivative instruments, including futures, forward contracts, options, structured securities, and swaps. Using derivatives can disproportionately increase losses and reduce opportunities for gains when stock prices, currency rates or interest rates are changing. The Fund may not fully benefit from or may lose money on derivatives if changes in their value do not correspond accurately to changes in the value of the Fund’s holdings. The other parties to certain derivative contracts present the same types of credit risk as issuers of fixed income securities. Derivatives can also make a fund less liquid and harder to value, especially in declining markets, and may increase the Fund’s volatility. There can be no assurance that the Fund’s use of derivative contracts will work as intended, and it is possible for the Fund to lose more than its original investment.

Developing and Emerging Markets Risk - Stocks of companies located in emerging markets may be substantially more volatile, and substantially less liquid, than the stocks of companies located in more developed foreign markets. Emerging market countries may experience higher inflation, interest rates and unemployment, greater social, economic, regulatory and political uncertainties, and greater volatility in currency exchange rates than more developed countries.

Exchange-Traded Fund (”ETF“) Risk - An ETF is subject to the risks associated with direct ownership of the securities comprising the index on which the ETF is based. Fund shareholders indirectly bear their proportionate share of the expenses of the ETFs in which the Fund invests. Lack of liquidity in an ETF could result in it being more volatile.

Focus Risk - Issuers in a single industry, sector, country, or region can react similarly to market, currency, political, economic, regulatory, geopolitical, and other conditions, and the Fund's performance will be affected by the conditions in the industries, sectors, countries and regions to which the Fund is exposed.

Foreign Securities Risk - Foreign markets can be more volatile than the U.S. market due to increased risks of adverse issuer, political, regulatory, market, currency valuation or economic developments. In addition, emerging markets may be more volatile and less liquid than the markets of more mature economies, and the securities of emerging markets issuers often are subject to rapid and large changes in price.

Growth Stock Risk - Growth stocks can be volatile for several reasons. Since they usually reinvest a high proportion of earnings in their own business, they may not pay the dividends usually associated with value stocks that can cushion their decline in a falling market. Also, since investors buy these stocks because of the expected superior earnings growth, earnings disappointments may result in sharp price declines.

Index Risk - It is possible the MSCI EAFE Index may perform unfavorably and/or underperform the market as a whole. The portion of the Fund sub-advised by ILIM is not actively managed and the portfolio managers do not attempt to take defensive positions in declining markets. Maintaining investments in securities regardless of market conditions or the performance of individual securities could cause the Fund’s return to be lower than if the portion of the Fund sub-advised by ILIM employed an active strategy.

Management Risk - A strategy used by the portfolio managers may fail to produce the intended results.

Market Risk - Stock markets are volatile and can decline significantly in response to adverse issuer, political, regulatory, market or economic developments in the U.S. and in other countries. Market risk may affect a single company, a sector of the economy, or the market as a whole.

Multi-Manager Risk - Each Sub-Adviser makes investment decisions independently. It is possible that the security selection processes of the Sub-Advisers may not complement one another and the Fund may have buy and sell transactions in the same security on the same day. The Sub-Advisers selected may underperform the market generally or other sub-advisers that could have been selected.

Small, Medium and Large Size Company Securities Risk - The stocks of small and medium size companies often involve more risk and volatility than those of larger companies. Among other things, small and medium size companies are often dependent on a small number of products and have limited financial resources, and there is generally less publicly available information about them. Securities of small and medium size companies have lower trading volume and are less liquid than securities of larger, more established companies. Companies with large market capitalizations go in and out of favor based on market and economic conditions, and could underperform returns of smaller companies.

Tracking Error Risk - The portion of the Fund sub-advised by ILIM may not be able to precisely track the performance of the MSCI EAFE Index.

Value Stock Risk - The value approach carries the risk that the market will not recognize a security’s intrinsic value for a long time, or that a stock judged to be undervalued may actually be appropriately valued.

An investment in the Fund is not a deposit with a bank, is not insured, endorsed or guaranteed by the FDIC or any government agency, and is subject to the possible loss of your original investment.

Performance

No performance data is provided because the Fund had not commenced operations as of the date of this Prospectus. Performance information will appear in future versions of this Prospectus after the Fund has annual returns for at least one complete calendar year.

Updated performance information may be obtained at www.greatwestfunds.com (the website does not form a part of this Prospectus).

[1] Because the Fund has not yet commenced operations, “Other Expenses” and “Acquired Fund Fees” are based on estimated amounts for the current fiscal year.

[2] Great-West Capital Management, LLC ("GWCM"), the Fund's investment adviser, has contractually agreed to waive fees or reimburse expenses that exceed 0.65% of the Fund's average daily net assets, excluding acquired fund fees and expenses, brokerage expenses, taxes, dividend interest on short sales, interest expenses, and any extraordinary expenses, including litigation costs (the "Expense Limit"). The agreement's current term ends on August 28, 2019 and automatically renews for one-year terms unless it is terminated by the Fund or GWCM upon written notice within 90 days of the end of the current term or upon termination of the investment advisory agreement between the Fund and GWCM. Under the agreement, GWCM may recoup, subject to Board approval, these waivers and reimbursements in future periods, not exceeding three years following the particular waiver/reimbursement, provided Total Annual Fund Operating Expenses plus such recoupment do not exceed the lesser of the Expense Limit that was in place at the time of the waiver/reimbursement or the Expense Limit in place at the time of recoupment.

XML

Label	Element	Value
Risk/Return:	rr_RiskReturnAbstract
Registrant Name	dei_EntityRegistrantName	GREAT-WEST FUNDS INC
Prospectus Date	rr_ProspectusDate	Jun. 25, 2018
Great-West Core Strategies: International Equity Fund
Risk/Return:	rr_RiskReturnAbstract
Risk/Return [Heading]	rr_RiskReturnHeading	Fund Summary
Objective [Heading]	rr_ObjectiveHeading	Investment Objective
Objective, Primary [Text Block]	rr_ObjectivePrimaryTextBlock	The Fund seeks long-term growth of capital.
Expense [Heading]	rr_ExpenseHeading	Fees and Expenses of the Fund
Expense Narrative [Text Block]	rr_ExpenseNarrativeTextBlock	This table describes the fees and expenses that you may pay if you buy and hold shares of the Fund. In addition to the fees and expenses described below, you may be required to pay your financial professional brokerage commissions when you purchase or sell Institutional Class shares.
Shareholder Fees Caption [Text]	rr_ShareholderFeesCaption	Shareholder Fees (fees paid directly from your investment)
Operating Expenses Caption [Text]	rr_OperatingExpensesCaption	Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)
Fee Waiver or Reimbursement over Assets, Date of Termination	rr_FeeWaiverOrReimbursementOverAssetsDateOfTermination	August 28, 2019
Portfolio Turnover [Heading]	rr_PortfolioTurnoverHeading	Portfolio Turnover
Portfolio Turnover [Text Block]	rr_PortfolioTurnoverTextBlock	The Fund pays transaction costs, such as commissions, when it buys and sells securities (or “turns over” its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when Fund shares are held in a taxable account. These costs, which are not reflected in annual fund operating expenses or in the example, affect the Fund’s performance.
Other Expenses, New Fund, Based on Estimates [Text]	rr_OtherExpensesNewFundBasedOnEstimates	“Other Expenses” and “Acquired Fund Fees” are based on estimated amounts for the current fiscal year.
Acquired Fund Fees and Expenses, Based on Estimates [Text]	rr_AcquiredFundFeesAndExpensesBasedOnEstimates	“Acquired Fund Fees” are based on estimated amounts for the current fiscal year.
Expense Example [Heading]	rr_ExpenseExampleHeading	Example
Expense Example Narrative [Text Block]	rr_ExpenseExampleNarrativeTextBlock	This Example is intended to help you compare the cost of investing in the Fund with the cost of investing in other mutual funds. The Example assumes that you invest $10,000 in the Fund for the time periods indicated and applies whether you hold or redeem all of your shares at the end of each period. The Example also assumes that the expense reimbursement is in place for the first year, that your investment has a 5% return each year, that all dividends and capital gains are reinvested, and that the Fund’s operating expenses are the amount shown in the fee table and remain the same for the years shown. Although your actual costs may be higher or lower, based on these assumptions, your costs would be:
Strategy [Heading]	rr_StrategyHeading	Principal Investment Strategies
Strategy Narrative [Text Block]	rr_StrategyNarrativeTextBlock	The Fund will, under normal circumstances, invest at least 80% of its net assets (plus the amount of any borrowings for investment purposes) in equity securities of issuers economically tied to countries other than the U.S., including those in emerging markets. Equity securities may be represented by other investment instruments, including depositary receipts, derivatives, and exchange-traded funds that track the return of a broadly-based international securities index. Derivatives instruments include futures, forward contracts, options, structured securities, and swaps. The Fund may from time to time, have significant investments in a particular sector or country, a small number of countries, or a particular geographic region; provided that the Fund will, under normal circumstances, invest in at least three different countries. The Fund may have exposure to non-U.S. stocks across any market capitalization and style and the Fund’s exposure will vary from time to time across sectors. The issuer of a security or other investment is generally deemed to be economically tied to a particular country other than the U.S. if: the security or other investment is issued or guaranteed by the government of that country or any of its agencies, authorities or instrumentalities; the issuer is organized under the laws of that country; the issuer maintains a principal office in that country; the issuer has its principal securities trading market in that country; the issuer derives 50% or more of its total revenues from goods sold or services performed in that country; the issuer has 50% or more of its assets in that country; or the issuer is included in an index which is representative of that country. The Fund’s investment portfolio is managed by three sub-advisers: Franklin Templeton Institutional, LLC (“Franklin Templeton”), Irish Life Investment Managers Limited (“ILIM”), and LSV Asset Management (“LSV”) (each, a Sub-Adviser,“ and collectively, the ”Sub-Advisers“). Franklin Templeton employs a disciplined, bottom-up investment approach to identify attractive investment opportunities that have higher expected revenue and earnings growth than their peers. ILIM seeks to invest in equity securities contained in the MSCI EAFE Index in as close as possible a proportion as each stock’s weight in the MSCI EAFE Index. LSV employs a deep-value strategy that seeks to invest in undervalued international companies with high potential for near-term price appreciation. GWCM maintains a strategic asset allocation of the Fund’s assets with each Sub-Adviser and reviews the asset allocations on a quarterly basis, or more frequently as deemed necessary. As of the date of this Prospectus, the target asset allocation is a 15% allocation of the Fund’s assets to Franklin Templeton, a 50% allocation of the Fund’s assets to ILIM, and a 35% allocation of the Fund’s assets to LSV. Notwithstanding these target allocations, initial allocations may vary from the target allocation and GWCM may change the asset allocations at any time and without shareholder notice or approval.
Risk [Heading]	rr_RiskHeading	Principal Investment Risks
Risk Narrative [Text Block]	rr_RiskNarrativeTextBlock	The following is a summary of the principal investment risks of investing in the Fund: Currency Risk - Adverse fluctuations in exchange rates between the U.S. Dollar and other currencies may cause the Fund to lose money on investments denominated in foreign currencies. Depositary Receipts Risk - Depositary receipts are generally subject to the same sort of risks as direct investments in a foreign country, such as, currency risk, political and economic risk, and market risk, because their values depend on the performance of a foreign security denominated in its home currency. Derivatives Risk - The Fund may invest in derivative instruments, including futures, forward contracts, options, structured securities, and swaps. Using derivatives can disproportionately increase losses and reduce opportunities for gains when stock prices, currency rates or interest rates are changing. The Fund may not fully benefit from or may lose money on derivatives if changes in their value do not correspond accurately to changes in the value of the Fund’s holdings. The other parties to certain derivative contracts present the same types of credit risk as issuers of fixed income securities. Derivatives can also make a fund less liquid and harder to value, especially in declining markets, and may increase the Fund’s volatility. There can be no assurance that the Fund’s use of derivative contracts will work as intended, and it is possible for the Fund to lose more than its original investment. Developing and Emerging Markets Risk - Stocks of companies located in emerging markets may be substantially more volatile, and substantially less liquid, than the stocks of companies located in more developed foreign markets. Emerging market countries may experience higher inflation, interest rates and unemployment, greater social, economic, regulatory and political uncertainties, and greater volatility in currency exchange rates than more developed countries. Exchange-Traded Fund (”ETF“) Risk - An ETF is subject to the risks associated with direct ownership of the securities comprising the index on which the ETF is based. Fund shareholders indirectly bear their proportionate share of the expenses of the ETFs in which the Fund invests. Lack of liquidity in an ETF could result in it being more volatile. Focus Risk - Issuers in a single industry, sector, country, or region can react similarly to market, currency, political, economic, regulatory, geopolitical, and other conditions, and the Fund's performance will be affected by the conditions in the industries, sectors, countries and regions to which the Fund is exposed. Foreign Securities Risk - Foreign markets can be more volatile than the U.S. market due to increased risks of adverse issuer, political, regulatory, market, currency valuation or economic developments. In addition, emerging markets may be more volatile and less liquid than the markets of more mature economies, and the securities of emerging markets issuers often are subject to rapid and large changes in price. Growth Stock Risk - Growth stocks can be volatile for several reasons. Since they usually reinvest a high proportion of earnings in their own business, they may not pay the dividends usually associated with value stocks that can cushion their decline in a falling market. Also, since investors buy these stocks because of the expected superior earnings growth, earnings disappointments may result in sharp price declines. Index Risk - It is possible the MSCI EAFE Index may perform unfavorably and/or underperform the market as a whole. The portion of the Fund sub-advised by ILIM is not actively managed and the portfolio managers do not attempt to take defensive positions in declining markets. Maintaining investments in securities regardless of market conditions or the performance of individual securities could cause the Fund’s return to be lower than if the portion of the Fund sub-advised by ILIM employed an active strategy. Management Risk - A strategy used by the portfolio managers may fail to produce the intended results. Market Risk - Stock markets are volatile and can decline significantly in response to adverse issuer, political, regulatory, market or economic developments in the U.S. and in other countries. Market risk may affect a single company, a sector of the economy, or the market as a whole. Multi-Manager Risk - Each Sub-Adviser makes investment decisions independently. It is possible that the security selection processes of the Sub-Advisers may not complement one another and the Fund may have buy and sell transactions in the same security on the same day. The Sub-Advisers selected may underperform the market generally or other sub-advisers that could have been selected. Small, Medium and Large Size Company Securities Risk - The stocks of small and medium size companies often involve more risk and volatility than those of larger companies. Among other things, small and medium size companies are often dependent on a small number of products and have limited financial resources, and there is generally less publicly available information about them. Securities of small and medium size companies have lower trading volume and are less liquid than securities of larger, more established companies. Companies with large market capitalizations go in and out of favor based on market and economic conditions, and could underperform returns of smaller companies. Tracking Error Risk - The portion of the Fund sub-advised by ILIM may not be able to precisely track the performance of the MSCI EAFE Index. Value Stock Risk - The value approach carries the risk that the market will not recognize a security’s intrinsic value for a long time, or that a stock judged to be undervalued may actually be appropriately valued. An investment in the Fund is not a deposit with a bank, is not insured, endorsed or guaranteed by the FDIC or any government agency, and is subject to the possible loss of your original investment.
Risk Lose Money [Text]	rr_RiskLoseMoney	is subject to the possible loss of your original investment.
Risk Not Insured Depository Institution [Text]	rr_RiskNotInsuredDepositoryInstitution	An investment in the Fund is not a deposit with a bank, is not insured, endorsed or guaranteed by the FDIC or any government agency,
Bar Chart and Performance Table [Heading]	rr_BarChartAndPerformanceTableHeading	Performance
Performance Narrative [Text Block]	rr_PerformanceNarrativeTextBlock	No performance data is provided because the Fund had not commenced operations as of the date of this Prospectus. Performance information will appear in future versions of this Prospectus after the Fund has annual returns for at least one complete calendar year. Updated performance information may be obtained at www.greatwestfunds.com (the website does not form a part of this Prospectus).
Performance One Year or Less [Text]	rr_PerformanceOneYearOrLess	No performance data is provided because the Fund had not commenced operations as of the date of this Prospectus.
Performance Availability Website Address [Text]	rr_PerformanceAvailabilityWebSiteAddress	www.greatwestfunds.com
Great-West Core Strategies: International Equity Fund | Institutional Class
Risk/Return:	rr_RiskReturnAbstract
Maximum Sales Charge (Load) Imposed on Purchases (as a percentage of offering price)	rr_MaximumSalesChargeImposedOnPurchasesOverOfferingPrice	none
Maximum Deferred Sales Charge (Load)	rr_MaximumDeferredSalesChargeOverOther	none
Maximum Sales Charge (Load) Imposed on Reinvested Dividends	rr_MaximumSalesChargeOnReinvestedDividendsAndDistributionsOverOther	none
Redemption Fee	rr_RedemptionFeeOverRedemption	none
Exchange Fee	rr_ExchangeFeeOverRedemption	none
Management Fees	rr_ManagementFeesOverAssets	0.53%	[1]
Distribution and Service (12b-1) Fees	rr_DistributionAndService12b1FeesOverAssets	none	[1]
Other Expenses	rr_OtherExpensesOverAssets	0.66%	[1]
Acquired Fund Fees and Expenses	rr_AcquiredFundFeesAndExpensesOverAssets	0.01%	[1]
Total Annual Fund Operating Expenses	rr_ExpensesOverAssets	1.20%	[1]
Fee Waiver and Expense Reimbursement	rr_FeeWaiverOrReimbursementOverAssets	0.54%	[1],[2]
Total Annual Fund Operating Expenses After Fee Waiver and Expense Reimbursement	rr_NetExpensesOverAssets	0.66%	[1]
1 Year	rr_ExpenseExampleYear01	$ 68
3 Years	rr_ExpenseExampleYear03	$ 328

[1] Because the Fund has not yet commenced operations, “Other Expenses” and “Acquired Fund Fees” are based on estimated amounts for the current fiscal year.

[2] Great-West Capital Management, LLC ("GWCM"), the Fund's investment adviser, has contractually agreed to waive fees or reimburse expenses that exceed 0.65% of the Fund's average daily net assets, excluding acquired fund fees and expenses, brokerage expenses, taxes, dividend interest on short sales, interest expenses, and any extraordinary expenses, including litigation costs (the "Expense Limit"). The agreement's current term ends on August 28, 2019 and automatically renews for one-year terms unless it is terminated by the Fund or GWCM upon written notice within 90 days of the end of the current term or upon termination of the investment advisory agreement between the Fund and GWCM. Under the agreement, GWCM may recoup, subject to Board approval, these waivers and reimbursements in future periods, not exceeding three years following the particular waiver/reimbursement, provided Total Annual Fund Operating Expenses plus such recoupment do not exceed the lesser of the Expense Limit that was in place at the time of the waiver/reimbursement or the Expense Limit in place at the time of recoupment.

XML

Great-West Core Strategies: Short Duration Bond Fund

Fund Summary

Investment Objective

The Fund seeks maximum total return that is consistent with preservation of capital and liquidity.

Fees and Expenses of the Fund

This table describes the fees and expenses that you may pay if you buy and hold shares of the Fund. In addition to the fees and expenses described below, you may be required to pay your financial professional brokerage commissions when you purchase or sell Institutional Class shares.

Shareholder Fees (fees paid directly from your investment)

Shareholder Fees	Great-West Core Strategies: Short Duration Bond Fund Institutional Class
Maximum Sales Charge (Load) Imposed on Purchases (as a percentage of offering price)	none
Maximum Deferred Sales Charge (Load)	none
Maximum Sales Charge (Load) Imposed on Reinvested Dividends	none
Redemption Fee	none
Exchange Fee	none

Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)

Annual Fund Operating Expenses	Great-West Core Strategies: Short Duration Bond Fund Institutional Class	[1]
Management Fees	0.23%
Distribution and Service (12b-1) Fees	none
Other Expenses	0.50%
Total Annual Fund Operating Expenses	0.73%
Fee Waiver and Expense Reimbursement	0.48%	[2]
Total Annual Fund Operating Expenses After Fee Waiver and Expense Reimbursement	0.25%

Example

This Example is intended to help you compare the cost of investing in the Fund with the cost of investing in other mutual funds.

The Example assumes that you invest $10,000 in the Fund for the time periods indicated and applies whether you hold or redeem all of your shares at the end of each period. The Example also assumes that the expense reimbursement is in place for the first year, that your investment has a 5% return each year, that all dividends and capital gains are reinvested, and that the Fund’s operating expenses are the amount shown in the fee table and remain the same for the years shown. Although your actual costs may be higher or lower, based on these assumptions, your costs would be:

Expense Example	1 Year	3 Years
Great-West Core Strategies: Short Duration Bond Fund | Institutional Class | USD ($)	25	184

Portfolio Turnover

The Fund pays transaction costs, such as commissions, when it buys and sells securities (or “turns over” its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when Fund shares are held in a taxable account. These costs, which are not reflected in annual fund operating expenses or in the example, affect the Fund’s performance.

Principal Investment Strategies

The Fund will, under normal circumstances, invest at least 80% of its net assets (plus the amount of any borrowings for investment purposes) in investment grade bonds. The Fund will select securities based on relative value, maturity, quality and sector. The Fund will maintain an actively managed portfolio of bonds selected from several categories, including U.S. Treasuries and agency securities, commercial and residential mortgage-backed securities, asset-backed securities, and corporate bonds. The Fund will maintain a dollar weighted average duration between one and three years based on the portfolio managers’ forecast for interest rates. The Fund may invest up to 20% its net assets in below investment grade quality (“high yield-high risk” or “junk”) bonds and bank loans. For purposes of pursuing its investment goals, the Fund may, from time to time, enter into derivative contracts, including futures contracts on U.S. Treasury securities.

Principal Investment Risks

The following is a summary of the principal investment risks of investing in the Fund:

Bank Loan Risk - Bank loans often involve borrowers whose financial conditions are troubled or uncertain and companies that are highly leveraged. The market for bank loans may not be highly liquid and the Fund may have difficulty selling bank loans. These investments expose the Fund to the credit risk of both the financial institution and the underlying borrower. Bank loans generally are subject to legal or contractual restrictions on resale. In addition, bank loans may have trade settlement periods extending beyond seven days. Bank loans may be structured such that they are not securities under securities laws and subject to securities laws protections against fraud and misrepresentation. As such, there can be no assurances that fraud or misrepresentation will not occur with respect to bank loans in which the Fund invests.

Credit Risk - An issuer may default on its obligations to pay principal and/or interest. A security’s value may be affected by changes in its credit quality rating or its issuer’s financial conditions.

Derivatives Risk - The Fund may invest in derivative instruments, including futures contracts on U.S. Treasury securities. Using derivatives can disproportionately increase losses and reduce opportunities for gains when stock prices, currency rates or interest rates are changing. The Fund may not fully benefit from or may lose money on derivatives if changes in their value do not correspond accurately to changes in the value of the Fund’s holdings. The other parties to certain derivative contracts present the same types of credit risk as issuers of fixed income securities. Derivatives can also make a fund less liquid and harder to value, especially in declining markets, and may increase the Fund’s volatility. There can be no assurance that the Fund’s use of derivative contracts will work as intended, and it is possible for the Fund to lose more than its original investment.

High Yield Securities Risk - Below investment grade (“high yield-high risk” or “junk”) bonds are speculative, have a higher degree of credit risk and interest rate risk, and may be less liquid and subject to greater volatility in market value than investment grade bonds.

Interest Rate Risk - The market value of a fixed income security is affected significantly by changes in interest rates. When interest rates rise, the market value of fixed income securities generally declines and when interest rates decline, market values of such securities generally rise. The longer a security’s maturity, that is, the time remaining until the final payment on the security is due, the greater the risk and the higher its yield. Conversely, the shorter a security’s maturity, the lower the risk and the lower its yield. In general, the longer the maturity or duration of a security, the greater its sensitivity to changes in interest rates. Recent and potential future changes in monetary policy may affect the level of interest rates.

Liquidity Risk - The fixed income securities in which the Fund invests may be less readily marketable and may be subject to greater fluctuation in price than other securities. When there is little or no active trading market for specific types of securities, legal or contractual restrictions on resale, or the reduced number and capacity of market participants to make a market in such security, it can become more difficult to sell the securities at or near their perceived value. In such a market, the value of such securities and the Fund’s share price may fall dramatically. Extraordinary and sudden changes in interest rates could disrupt the market for fixed-income securities and result in fluctuations in the Fund’s net asset value. Increased redemptions due to a rise in interest rates may require the Fund to liquidate its holdings at an unfavorable time and/or under adverse or disadvantageous conditions which may negatively affect the Fund.

Management Risk - A strategy used by the portfolio managers may fail to produce the intended results.

Market Risk - The market values of securities owned by the Fund will go up and down, sometimes rapidly or unpredictably. A security's market value may be reduced by market activity or other results of supply and demand unrelated to the issuer. This is a basic risk associated with all securities. When there are more sellers than buyers, prices tend to fall. Likewise, when there are more buyers than sellers, prices tend to rise.

Mortgage-Backed and Asset-Backed Securities Risk – Mortgage-backed and asset-backed securities are subject to interest rate risk and credit risk. These securities are also subject to the risk that borrowers will prepay the principal on their loans more quickly than expected (prepayment risk) or more slowly than expected (extension risk), which will affect the yield, average life and price of the securities. In addition, faster than expected prepayments may cause the Fund to invest the prepaid principal in lower yielding securities, and slower than expected prepayments may reduce the potential for the Fund to invest in higher yielding securities.

U.S. Government Securities Risk – U.S. Government securities may be adversely affected by changes in interest rates or a default by, or decline in the credit quality of, the U.S. Government.

U.S. Government-Sponsored Securities Risk - Securities issued by U.S. Government-sponsored enterprises (“GSEs”), such as the Federal Home Loan Mortgage Corporation, the Federal National Mortgage Association and the Federal Home Loan Banks, are not issued or guaranteed by the U.S. Treasury.

An investment in the Fund is not a deposit with a bank, is not insured, endorsed or guaranteed by the FDIC or any government agency, and is subject to the possible loss of your original investment.

Performance

No performance data is provided because the Fund had not commenced operations as of the date of this Prospectus. Performance information will appear in future versions of this Prospectus after the Fund has annual returns for at least one complete calendar year.

Updated performance information may be obtained at www.greatwestfunds.com (the website does not form a part of this Prospectus).

[1] Because the Fund has not yet commenced operations, “Other Expenses” are based on estimated amounts for the current fiscal year.

[2] Great-West Capital Management, LLC ("GWCM"), the Fund's investment adviser, has contractually agreed to waive fees or reimburse expenses that exceed 0.25% of the Fund's average daily net assets, excluding brokerage expenses, taxes, dividend interest on short sales, interest expenses, and any extraordinary expenses, including litigation costs (the "Expense Limit"). The agreement's current term ends on August 28, 2019 and automatically renews for one-year terms unless it is terminated by the Fund or GWCM upon written notice within 90 days of the end of the current term or upon termination of the investment advisory agreement between the Fund and GWCM. Under the agreement, GWCM may recoup, subject to Board approval, these waivers and reimbursements in future periods, not exceeding three years following the particular waiver/reimbursement, provided Total Annual Fund Operating Expenses plus such recoupment do not exceed the lesser of the Expense Limit that was in place at the time of the waiver/reimbursement or the Expense Limit in place at the time of recoupment.

XML

Label	Element	Value
Risk/Return:	rr_RiskReturnAbstract
Registrant Name	dei_EntityRegistrantName	GREAT-WEST FUNDS INC
Prospectus Date	rr_ProspectusDate	Jun. 25, 2018
Great-West Core Strategies: Short Duration Bond Fund
Risk/Return:	rr_RiskReturnAbstract
Risk/Return [Heading]	rr_RiskReturnHeading	Fund Summary
Objective [Heading]	rr_ObjectiveHeading	Investment Objective
Objective, Primary [Text Block]	rr_ObjectivePrimaryTextBlock	The Fund seeks maximum total return that is consistent with preservation of capital and liquidity.
Expense [Heading]	rr_ExpenseHeading	Fees and Expenses of the Fund
Expense Narrative [Text Block]	rr_ExpenseNarrativeTextBlock	This table describes the fees and expenses that you may pay if you buy and hold shares of the Fund. In addition to the fees and expenses described below, you may be required to pay your financial professional brokerage commissions when you purchase or sell Institutional Class shares.
Shareholder Fees Caption [Text]	rr_ShareholderFeesCaption	Shareholder Fees (fees paid directly from your investment)
Operating Expenses Caption [Text]	rr_OperatingExpensesCaption	Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)
Fee Waiver or Reimbursement over Assets, Date of Termination	rr_FeeWaiverOrReimbursementOverAssetsDateOfTermination	August 28, 2019
Portfolio Turnover [Heading]	rr_PortfolioTurnoverHeading	Portfolio Turnover
Portfolio Turnover [Text Block]	rr_PortfolioTurnoverTextBlock	The Fund pays transaction costs, such as commissions, when it buys and sells securities (or “turns over” its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when Fund shares are held in a taxable account. These costs, which are not reflected in annual fund operating expenses or in the example, affect the Fund’s performance.
Other Expenses, New Fund, Based on Estimates [Text]	rr_OtherExpensesNewFundBasedOnEstimates	“Other Expenses” are based on estimated amounts for the current fiscal year.
Expense Example [Heading]	rr_ExpenseExampleHeading	Example
Expense Example Narrative [Text Block]	rr_ExpenseExampleNarrativeTextBlock	This Example is intended to help you compare the cost of investing in the Fund with the cost of investing in other mutual funds. The Example assumes that you invest $10,000 in the Fund for the time periods indicated and applies whether you hold or redeem all of your shares at the end of each period. The Example also assumes that the expense reimbursement is in place for the first year, that your investment has a 5% return each year, that all dividends and capital gains are reinvested, and that the Fund’s operating expenses are the amount shown in the fee table and remain the same for the years shown. Although your actual costs may be higher or lower, based on these assumptions, your costs would be:
Strategy [Heading]	rr_StrategyHeading	Principal Investment Strategies
Strategy Narrative [Text Block]	rr_StrategyNarrativeTextBlock	The Fund will, under normal circumstances, invest at least 80% of its net assets (plus the amount of any borrowings for investment purposes) in investment grade bonds. The Fund will select securities based on relative value, maturity, quality and sector. The Fund will maintain an actively managed portfolio of bonds selected from several categories, including U.S. Treasuries and agency securities, commercial and residential mortgage-backed securities, asset-backed securities, and corporate bonds. The Fund will maintain a dollar weighted average duration between one and three years based on the portfolio managers’ forecast for interest rates. The Fund may invest up to 20% its net assets in below investment grade quality (“high yield-high risk” or “junk”) bonds and bank loans. For purposes of pursuing its investment goals, the Fund may, from time to time, enter into derivative contracts, including futures contracts on U.S. Treasury securities.
Risk [Heading]	rr_RiskHeading	Principal Investment Risks
Risk Narrative [Text Block]	rr_RiskNarrativeTextBlock	The following is a summary of the principal investment risks of investing in the Fund: Bank Loan Risk - Bank loans often involve borrowers whose financial conditions are troubled or uncertain and companies that are highly leveraged. The market for bank loans may not be highly liquid and the Fund may have difficulty selling bank loans. These investments expose the Fund to the credit risk of both the financial institution and the underlying borrower. Bank loans generally are subject to legal or contractual restrictions on resale. In addition, bank loans may have trade settlement periods extending beyond seven days. Bank loans may be structured such that they are not securities under securities laws and subject to securities laws protections against fraud and misrepresentation. As such, there can be no assurances that fraud or misrepresentation will not occur with respect to bank loans in which the Fund invests. Credit Risk - An issuer may default on its obligations to pay principal and/or interest. A security’s value may be affected by changes in its credit quality rating or its issuer’s financial conditions. Derivatives Risk - The Fund may invest in derivative instruments, including futures contracts on U.S. Treasury securities. Using derivatives can disproportionately increase losses and reduce opportunities for gains when stock prices, currency rates or interest rates are changing. The Fund may not fully benefit from or may lose money on derivatives if changes in their value do not correspond accurately to changes in the value of the Fund’s holdings. The other parties to certain derivative contracts present the same types of credit risk as issuers of fixed income securities. Derivatives can also make a fund less liquid and harder to value, especially in declining markets, and may increase the Fund’s volatility. There can be no assurance that the Fund’s use of derivative contracts will work as intended, and it is possible for the Fund to lose more than its original investment. High Yield Securities Risk - Below investment grade (“high yield-high risk” or “junk”) bonds are speculative, have a higher degree of credit risk and interest rate risk, and may be less liquid and subject to greater volatility in market value than investment grade bonds. Interest Rate Risk - The market value of a fixed income security is affected significantly by changes in interest rates. When interest rates rise, the market value of fixed income securities generally declines and when interest rates decline, market values of such securities generally rise. The longer a security’s maturity, that is, the time remaining until the final payment on the security is due, the greater the risk and the higher its yield. Conversely, the shorter a security’s maturity, the lower the risk and the lower its yield. In general, the longer the maturity or duration of a security, the greater its sensitivity to changes in interest rates. Recent and potential future changes in monetary policy may affect the level of interest rates. Liquidity Risk - The fixed income securities in which the Fund invests may be less readily marketable and may be subject to greater fluctuation in price than other securities. When there is little or no active trading market for specific types of securities, legal or contractual restrictions on resale, or the reduced number and capacity of market participants to make a market in such security, it can become more difficult to sell the securities at or near their perceived value. In such a market, the value of such securities and the Fund’s share price may fall dramatically. Extraordinary and sudden changes in interest rates could disrupt the market for fixed-income securities and result in fluctuations in the Fund’s net asset value. Increased redemptions due to a rise in interest rates may require the Fund to liquidate its holdings at an unfavorable time and/or under adverse or disadvantageous conditions which may negatively affect the Fund. Management Risk - A strategy used by the portfolio managers may fail to produce the intended results. Market Risk - The market values of securities owned by the Fund will go up and down, sometimes rapidly or unpredictably. A security's market value may be reduced by market activity or other results of supply and demand unrelated to the issuer. This is a basic risk associated with all securities. When there are more sellers than buyers, prices tend to fall. Likewise, when there are more buyers than sellers, prices tend to rise. Mortgage-Backed and Asset-Backed Securities Risk – Mortgage-backed and asset-backed securities are subject to interest rate risk and credit risk. These securities are also subject to the risk that borrowers will prepay the principal on their loans more quickly than expected (prepayment risk) or more slowly than expected (extension risk), which will affect the yield, average life and price of the securities. In addition, faster than expected prepayments may cause the Fund to invest the prepaid principal in lower yielding securities, and slower than expected prepayments may reduce the potential for the Fund to invest in higher yielding securities. U.S. Government Securities Risk – U.S. Government securities may be adversely affected by changes in interest rates or a default by, or decline in the credit quality of, the U.S. Government. U.S. Government-Sponsored Securities Risk - Securities issued by U.S. Government-sponsored enterprises (“GSEs”), such as the Federal Home Loan Mortgage Corporation, the Federal National Mortgage Association and the Federal Home Loan Banks, are not issued or guaranteed by the U.S. Treasury. An investment in the Fund is not a deposit with a bank, is not insured, endorsed or guaranteed by the FDIC or any government agency, and is subject to the possible loss of your original investment.
Risk Lose Money [Text]	rr_RiskLoseMoney	is subject to the possible loss of your original investment.
Risk Not Insured Depository Institution [Text]	rr_RiskNotInsuredDepositoryInstitution	An investment in the Fund is not a deposit with a bank, is not insured, endorsed or guaranteed by the FDIC or any government agency,
Bar Chart and Performance Table [Heading]	rr_BarChartAndPerformanceTableHeading	Performance
Performance Narrative [Text Block]	rr_PerformanceNarrativeTextBlock	No performance data is provided because the Fund had not commenced operations as of the date of this Prospectus. Performance information will appear in future versions of this Prospectus after the Fund has annual returns for at least one complete calendar year. Updated performance information may be obtained at www.greatwestfunds.com (the website does not form a part of this Prospectus).
Performance One Year or Less [Text]	rr_PerformanceOneYearOrLess	No performance data is provided because the Fund had not commenced operations as of the date of this Prospectus.
Performance Availability Website Address [Text]	rr_PerformanceAvailabilityWebSiteAddress	www.greatwestfunds.com
Great-West Core Strategies: Short Duration Bond Fund | Institutional Class
Risk/Return:	rr_RiskReturnAbstract
Maximum Sales Charge (Load) Imposed on Purchases (as a percentage of offering price)	rr_MaximumSalesChargeImposedOnPurchasesOverOfferingPrice	none
Maximum Deferred Sales Charge (Load)	rr_MaximumDeferredSalesChargeOverOther	none
Maximum Sales Charge (Load) Imposed on Reinvested Dividends	rr_MaximumSalesChargeOnReinvestedDividendsAndDistributionsOverOther	none
Redemption Fee	rr_RedemptionFeeOverRedemption	none
Exchange Fee	rr_ExchangeFeeOverRedemption	none
Management Fees	rr_ManagementFeesOverAssets	0.23%	[1]
Distribution and Service (12b-1) Fees	rr_DistributionAndService12b1FeesOverAssets	none	[1]
Other Expenses	rr_OtherExpensesOverAssets	0.50%	[1]
Total Annual Fund Operating Expenses	rr_ExpensesOverAssets	0.73%	[1]
Fee Waiver and Expense Reimbursement	rr_FeeWaiverOrReimbursementOverAssets	0.48%	[1],[2]
Total Annual Fund Operating Expenses After Fee Waiver and Expense Reimbursement	rr_NetExpensesOverAssets	0.25%	[1]
1 Year	rr_ExpenseExampleYear01	$ 25
3 Years	rr_ExpenseExampleYear03	$ 184

[1] Because the Fund has not yet commenced operations, “Other Expenses” are based on estimated amounts for the current fiscal year.

[2] Great-West Capital Management, LLC ("GWCM"), the Fund's investment adviser, has contractually agreed to waive fees or reimburse expenses that exceed 0.25% of the Fund's average daily net assets, excluding brokerage expenses, taxes, dividend interest on short sales, interest expenses, and any extraordinary expenses, including litigation costs (the "Expense Limit"). The agreement's current term ends on August 28, 2019 and automatically renews for one-year terms unless it is terminated by the Fund or GWCM upon written notice within 90 days of the end of the current term or upon termination of the investment advisory agreement between the Fund and GWCM. Under the agreement, GWCM may recoup, subject to Board approval, these waivers and reimbursements in future periods, not exceeding three years following the particular waiver/reimbursement, provided Total Annual Fund Operating Expenses plus such recoupment do not exceed the lesser of the Expense Limit that was in place at the time of the waiver/reimbursement or the Expense Limit in place at the time of recoupment.

XML

Great-West Core Strategies: U.S. Equity Fund

Fund Summary

Investment Objective

The Fund seeks long-term growth of capital.

Fees and Expenses of the Fund

This table describes the fees and expenses that you may pay if you buy and hold shares of the Fund. In addition to the fees and expenses described below, you may be required to pay your financial professional brokerage commissions when you purchase or sell Institutional Class shares.

Shareholder Fees (fees paid directly from your investment)

Shareholder Fees	Great-West Core Strategies: U.S. Equity Fund Institutional Class
Maximum Sales Charge (Load) Imposed on Purchases (as a percentage of offering price)	none
Maximum Deferred Sales Charge (Load)	none
Maximum Sales Charge (Load) Imposed on Reinvested Dividends	none
Redemption Fee	none
Exchange Fee	none

Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)

Annual Fund Operating Expenses	Great-West Core Strategies: U.S. Equity Fund Institutional Class	[1]
Management Fees	0.47%
Distribution and Service (12b-1) Fees	none
Other Expenses	0.13%
Acquired Fund Fees and Expenses	0.01%
Total Annual Fund Operating Expenses	0.61%
Fee Waiver and Expense Reimbursement	0.05%	[2]
Total Annual Fund Operating Expenses After Fee Waiver and Expense Reimbursement	0.56%

Example

This Example is intended to help you compare the cost of investing in the Fund with the cost of investing in other mutual funds.

The Example assumes that you invest $10,000 in the Fund for the time periods indicated and applies whether you hold or redeem all of your shares at the end of each period. The Example also assumes that the expense reimbursement is in place for the first year, that your investment has a 5% return each year, that all dividends and capital gains are reinvested, and that the Fund’s operating expenses are the amount shown in the fee table and remain the same for the years shown. Although your actual costs may be higher or lower, based on these assumptions, your costs would be:

Expense Example	1 Year	3 Years
Great-West Core Strategies: U.S. Equity Fund | Institutional Class | USD ($)	58	192

Portfolio Turnover

The Fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when Fund shares are held in a taxable account. These costs, which are not reflected in annual fund operating expenses or in the example, affect the Fund's performance.

Principal Investment Strategies

The Fund will, under normal circumstances, invest at least 80% of its net assets (plus the amount of any borrowings for investment purposes) in equity securities of U.S. companies. Equity securities may be represented by other investment instruments, including derivatives, and exchange-traded funds that track the return of a broadly-based U.S. securities index. Derivatives instruments include forward contracts, swaps, futures contracts and options on futures. U.S. companies include companies that are listed or traded principally in, have their primary operations in, are domiciled in or derive a majority of their revenue from the United States. The Fund may have exposure to U.S. stocks across any market capitalization and style and the Fund’s exposure will vary from time to time across sectors.

The Fund’s investment portfolio will be managed by four sub-advisers: Irish Life Investment Managers Limited (“ILIM”), J.P. Morgan Investment Management Inc. (“JPMorgan”), Loomis, Sayles & Company, L.P. (“Loomis Sayles”) and Putnam Investment Management, LLC (“Putnam”) (each, a “Sub-Adviser,” and collectively, the “Sub-Advisers”). ILIM seeks to invest in equity securities contained in the Standard & Poor’s (“S&P”) 500^® Index (“S&P 500 Index”) in as close as possible a proportion as each stock’s weight in the S& P 500 Index. JPMorgan seeks to invest in equity securities of large, well-established companies with market-capitalization equal to those within the universe of the Russell 1000^® Growth Index at the time of purchase. Loomis Sayles seeks to invest in equity securities of small companies, which are of a size similar to those in the Russell 2000^® Index at the time of purchase. Putnam seeks to invest in securities of mid-size and large U.S. companies, which are of a size similar to those in the Russell 1000^® Value Index, with a focus on value stocks that offer the potential for capital growth, current income, or both.

GWCM maintains a strategic asset allocation of the Fund’s assets with each Sub-Adviser and among asset classes. GWCM reviews the asset allocations on a quarterly basis, or more frequently as deemed necessary. As of the date of this Prospectus, the target asset allocation among the Sub-Advisers is a 50% allocation of the Fund’s assets to ILIM, a 10% allocation of the Fund’s assets to JPMorgan, a 20% allocation of the Fund’s assets to Loomis Sayles, and a 20% allocation of the Fund’s assets to Putnam. The Fund currently expects (as of the date of this Prospectus) to invest 60-90% of its net assets in equity securities of large-capitalization companies that, at the time of purchase, are similar in size to companies in the Russell 1000 Index and 10-40% of its net assets in equity securities of small-capitalization companies that, at the time of purchase, are similar in size to companies in the Russell 2000 Index. Notwithstanding these target allocations, initial allocations may vary from the target allocation and GWCM may change the asset allocations at any time and without shareholder notice or approval.

Principal Investment Risks

The following is a summary of the principal investment risks of investing in the Fund:

Derivatives Risk - The Fund may invest in derivative instruments, including forward contracts, swaps, futures contracts and options on futures. Using derivatives can disproportionately increase losses and reduce opportunities for gains when stock prices, currency rates or interest rates are changing. The Fund may not fully benefit from or may lose money on derivatives if changes in their value do not correspond accurately to changes in the value of the Fund’s holdings. The other parties to certain derivative contracts present the same types of credit risk as issuers of fixed income securities. Derivatives can also make a fund less liquid and harder to value, especially in declining markets, and may increase the Fund’s volatility. There can be no assurance that the Fund’s use of derivative contracts will work as intended, and it is possible for the Fund to lose more than its original investment.

Exchange-Traded Fund (“ETF”) Risk - An ETF is subject to the risks associated with direct ownership of the securities comprising the index on which the ETF is based. Fund shareholders indirectly bear their proportionate share of the expenses of the ETFs in which the Fund invests. Lack of liquidity in an ETF could result in it being more volatile.

Growth Stock Risk - Growth stocks can be volatile for several reasons. Since they usually reinvest a high proportion of earnings in their own business, they may not pay the dividends usually associated with value stocks that can cushion their decline in a falling market. Also, since investors buy these stocks because of the expected superior earnings growth, earnings disappointments may result in sharp price declines.

Index Risk - It is possible the S&P 500 Index may perform unfavorably and/or underperform the market as a whole. The portion of the Fund sub-advised by ILIM is not actively managed and the portfolio managers do not attempt to take defensive positions in declining markets. Maintaining investments in securities regardless of market conditions or the performance of individual securities could cause the Fund’s return to be lower than if the portion of the Fund sub-advised by ILIM employed an active strategy.

Liquidity Risk - Securities in which the Fund invests may be less readily marketable and may be subject to greater fluctuation in price than other securities. Investments in many, but not all, foreign securities tend to have greater exposure to liquidity risk than domestic securities.

Management Risk - A strategy used by the portfolio managers may fail to produce the intended results.

Market Risk - Stock markets are volatile and can decline significantly in response to adverse issuer, political, regulatory, market or economic developments in the U.S. and in other countries. Market risk may affect a single company, a sector of the economy, or the market as a whole.

Multi-Manager Risk - Each Sub-Adviser makes investment decisions independently. It is possible that the security selection processes of the Sub-Advisers may not complement one another and the Fund may have buy and sell transactions in the same security on the same day. The Sub-Advisers selected may underperform the market generally or other sub-advisers that could have been selected.

Small, Medium and Large Size Company Securities Risk - The stocks of small and medium size companies often involve more risk and volatility than those of larger companies. Among other things, small and medium size companies are often dependent on a small number of products and have limited financial resources, and there is generally less publicly available information about them. Securities of small and medium size companies have lower trading volume and are less liquid than securities of larger, more established companies. Companies with large market capitalizations go in and out of favor based on market and economic conditions, and could underperform returns of smaller companies.

Tracking Error Risk - The portion of the Fund sub-advised by ILIM may not be able to precisely track the performance of the S&P 500 Index.

Value Stock Risk - The value approach carries the risk that the market will not recognize a security’s intrinsic value for a long time, or that a stock judged to be undervalued may actually be appropriately valued.

An investment in the Fund is not a deposit with a bank, is not insured, endorsed or guaranteed by the FDIC or any government agency, and is subject to the possible loss of your original investment.

Performance

No performance data is provided because the Fund had not commenced operations as of the date of this Prospectus. Performance information will appear in future versions of this Prospectus after the Fund has annual returns for at least one complete calendar year.

Updated performance information may be obtained at www.greatwestfunds.com (the website does not form a part of this Prospectus).

[1] Because the Fund has not yet commenced operations, "Other Expenses" and "Acquired Fund Fees" are based on estimated amounts for the current fiscal year.

[2] Great-West Capital Management, LLC ("GWCM"), the Fund's investment adviser, has contractually agreed to waive fees or reimburse expenses that exceed 0.55% of the Fund's average daily net assets, excluding acquired fund fees and expenses, brokerage expenses, taxes, dividend interest on short sales, interest expenses, and any extraordinary expenses, including litigation costs (the "Expense Limit"). The agreement's current term ends on August 28, 2019 and automatically renews for one-year terms unless it is terminated by the Fund or GWCM upon written notice within 90 days of the end of the current term or upon termination of the investment advisory agreement between the Fund and GWCM. Under the agreement, GWCM may recoup, subject to Board approval, these waivers and reimbursements in future periods, not exceeding three years following the particular waiver/reimbursement, provided Total Annual Fund Operating Expenses plus such recoupment do not exceed the lesser of the Expense Limit that was in place at the time of the waiver/reimbursement or the Expense Limit in place at the time of recoupment.

XML

Label	Element	Value
Risk/Return:	rr_RiskReturnAbstract
Registrant Name	dei_EntityRegistrantName	GREAT-WEST FUNDS INC
Prospectus Date	rr_ProspectusDate	Jun. 25, 2018
Great-West Core Strategies: U.S. Equity Fund
Risk/Return:	rr_RiskReturnAbstract
Risk/Return [Heading]	rr_RiskReturnHeading	Fund Summary
Objective [Heading]	rr_ObjectiveHeading	Investment Objective
Objective, Primary [Text Block]	rr_ObjectivePrimaryTextBlock	The Fund seeks long-term growth of capital.
Expense [Heading]	rr_ExpenseHeading	Fees and Expenses of the Fund
Expense Narrative [Text Block]	rr_ExpenseNarrativeTextBlock	This table describes the fees and expenses that you may pay if you buy and hold shares of the Fund. In addition to the fees and expenses described below, you may be required to pay your financial professional brokerage commissions when you purchase or sell Institutional Class shares.
Shareholder Fees Caption [Text]	rr_ShareholderFeesCaption	Shareholder Fees (fees paid directly from your investment)
Operating Expenses Caption [Text]	rr_OperatingExpensesCaption	Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)
Fee Waiver or Reimbursement over Assets, Date of Termination	rr_FeeWaiverOrReimbursementOverAssetsDateOfTermination	August 28, 2019
Portfolio Turnover [Heading]	rr_PortfolioTurnoverHeading	Portfolio Turnover
Portfolio Turnover [Text Block]	rr_PortfolioTurnoverTextBlock	The Fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when Fund shares are held in a taxable account. These costs, which are not reflected in annual fund operating expenses or in the example, affect the Fund's performance.
Other Expenses, New Fund, Based on Estimates [Text]	rr_OtherExpensesNewFundBasedOnEstimates	"Other Expenses" and "Acquired Fund Fees" are based on estimated amounts for the current fiscal year.
Acquired Fund Fees and Expenses, Based on Estimates [Text]	rr_AcquiredFundFeesAndExpensesBasedOnEstimates	"Acquired Fund Fees" are based on estimated amounts for the current fiscal year.
Expense Example [Heading]	rr_ExpenseExampleHeading	Example
Expense Example Narrative [Text Block]	rr_ExpenseExampleNarrativeTextBlock	This Example is intended to help you compare the cost of investing in the Fund with the cost of investing in other mutual funds. The Example assumes that you invest $10,000 in the Fund for the time periods indicated and applies whether you hold or redeem all of your shares at the end of each period. The Example also assumes that the expense reimbursement is in place for the first year, that your investment has a 5% return each year, that all dividends and capital gains are reinvested, and that the Fund’s operating expenses are the amount shown in the fee table and remain the same for the years shown. Although your actual costs may be higher or lower, based on these assumptions, your costs would be:
Strategy [Heading]	rr_StrategyHeading	Principal Investment Strategies
Strategy Narrative [Text Block]	rr_StrategyNarrativeTextBlock	The Fund will, under normal circumstances, invest at least 80% of its net assets (plus the amount of any borrowings for investment purposes) in equity securities of U.S. companies. Equity securities may be represented by other investment instruments, including derivatives, and exchange-traded funds that track the return of a broadly-based U.S. securities index. Derivatives instruments include forward contracts, swaps, futures contracts and options on futures. U.S. companies include companies that are listed or traded principally in, have their primary operations in, are domiciled in or derive a majority of their revenue from the United States. The Fund may have exposure to U.S. stocks across any market capitalization and style and the Fund’s exposure will vary from time to time across sectors. The Fund’s investment portfolio will be managed by four sub-advisers: Irish Life Investment Managers Limited (“ILIM”), J.P. Morgan Investment Management Inc. (“JPMorgan”), Loomis, Sayles & Company, L.P. (“Loomis Sayles”) and Putnam Investment Management, LLC (“Putnam”) (each, a “Sub-Adviser,” and collectively, the “Sub-Advisers”). ILIM seeks to invest in equity securities contained in the Standard & Poor’s (“S&P”) 500® Index (“S&P 500 Index”) in as close as possible a proportion as each stock’s weight in the S& P 500 Index. JPMorgan seeks to invest in equity securities of large, well-established companies with market-capitalization equal to those within the universe of the Russell 1000® Growth Index at the time of purchase. Loomis Sayles seeks to invest in equity securities of small companies, which are of a size similar to those in the Russell 2000® Index at the time of purchase. Putnam seeks to invest in securities of mid-size and large U.S. companies, which are of a size similar to those in the Russell 1000® Value Index, with a focus on value stocks that offer the potential for capital growth, current income, or both. GWCM maintains a strategic asset allocation of the Fund’s assets with each Sub-Adviser and among asset classes. GWCM reviews the asset allocations on a quarterly basis, or more frequently as deemed necessary. As of the date of this Prospectus, the target asset allocation among the Sub-Advisers is a 50% allocation of the Fund’s assets to ILIM, a 10% allocation of the Fund’s assets to JPMorgan, a 20% allocation of the Fund’s assets to Loomis Sayles, and a 20% allocation of the Fund’s assets to Putnam. The Fund currently expects (as of the date of this Prospectus) to invest 60-90% of its net assets in equity securities of large-capitalization companies that, at the time of purchase, are similar in size to companies in the Russell 1000 Index and 10-40% of its net assets in equity securities of small-capitalization companies that, at the time of purchase, are similar in size to companies in the Russell 2000 Index. Notwithstanding these target allocations, initial allocations may vary from the target allocation and GWCM may change the asset allocations at any time and without shareholder notice or approval.
Risk [Heading]	rr_RiskHeading	Principal Investment Risks
Risk Narrative [Text Block]	rr_RiskNarrativeTextBlock	The following is a summary of the principal investment risks of investing in the Fund: Derivatives Risk - The Fund may invest in derivative instruments, including forward contracts, swaps, futures contracts and options on futures. Using derivatives can disproportionately increase losses and reduce opportunities for gains when stock prices, currency rates or interest rates are changing. The Fund may not fully benefit from or may lose money on derivatives if changes in their value do not correspond accurately to changes in the value of the Fund’s holdings. The other parties to certain derivative contracts present the same types of credit risk as issuers of fixed income securities. Derivatives can also make a fund less liquid and harder to value, especially in declining markets, and may increase the Fund’s volatility. There can be no assurance that the Fund’s use of derivative contracts will work as intended, and it is possible for the Fund to lose more than its original investment. Exchange-Traded Fund (“ETF”) Risk - An ETF is subject to the risks associated with direct ownership of the securities comprising the index on which the ETF is based. Fund shareholders indirectly bear their proportionate share of the expenses of the ETFs in which the Fund invests. Lack of liquidity in an ETF could result in it being more volatile. Growth Stock Risk - Growth stocks can be volatile for several reasons. Since they usually reinvest a high proportion of earnings in their own business, they may not pay the dividends usually associated with value stocks that can cushion their decline in a falling market. Also, since investors buy these stocks because of the expected superior earnings growth, earnings disappointments may result in sharp price declines. Index Risk - It is possible the S&P 500 Index may perform unfavorably and/or underperform the market as a whole. The portion of the Fund sub-advised by ILIM is not actively managed and the portfolio managers do not attempt to take defensive positions in declining markets. Maintaining investments in securities regardless of market conditions or the performance of individual securities could cause the Fund’s return to be lower than if the portion of the Fund sub-advised by ILIM employed an active strategy. Liquidity Risk - Securities in which the Fund invests may be less readily marketable and may be subject to greater fluctuation in price than other securities. Investments in many, but not all, foreign securities tend to have greater exposure to liquidity risk than domestic securities. Management Risk - A strategy used by the portfolio managers may fail to produce the intended results. Market Risk - Stock markets are volatile and can decline significantly in response to adverse issuer, political, regulatory, market or economic developments in the U.S. and in other countries. Market risk may affect a single company, a sector of the economy, or the market as a whole. Multi-Manager Risk - Each Sub-Adviser makes investment decisions independently. It is possible that the security selection processes of the Sub-Advisers may not complement one another and the Fund may have buy and sell transactions in the same security on the same day. The Sub-Advisers selected may underperform the market generally or other sub-advisers that could have been selected. Small, Medium and Large Size Company Securities Risk - The stocks of small and medium size companies often involve more risk and volatility than those of larger companies. Among other things, small and medium size companies are often dependent on a small number of products and have limited financial resources, and there is generally less publicly available information about them. Securities of small and medium size companies have lower trading volume and are less liquid than securities of larger, more established companies. Companies with large market capitalizations go in and out of favor based on market and economic conditions, and could underperform returns of smaller companies. Tracking Error Risk - The portion of the Fund sub-advised by ILIM may not be able to precisely track the performance of the S&P 500 Index. Value Stock Risk - The value approach carries the risk that the market will not recognize a security’s intrinsic value for a long time, or that a stock judged to be undervalued may actually be appropriately valued. An investment in the Fund is not a deposit with a bank, is not insured, endorsed or guaranteed by the FDIC or any government agency, and is subject to the possible loss of your original investment.
Risk Lose Money [Text]	rr_RiskLoseMoney	is subject to the possible loss of your original investment.
Risk Not Insured Depository Institution [Text]	rr_RiskNotInsuredDepositoryInstitution	An investment in the Fund is not a deposit with a bank, is not insured, endorsed or guaranteed by the FDIC or any government agency,
Bar Chart and Performance Table [Heading]	rr_BarChartAndPerformanceTableHeading	Performance
Performance Narrative [Text Block]	rr_PerformanceNarrativeTextBlock	No performance data is provided because the Fund had not commenced operations as of the date of this Prospectus. Performance information will appear in future versions of this Prospectus after the Fund has annual returns for at least one complete calendar year. Updated performance information may be obtained at www.greatwestfunds.com (the website does not form a part of this Prospectus).
Performance One Year or Less [Text]	rr_PerformanceOneYearOrLess	No performance data is provided because the Fund had not commenced operations as of the date of this Prospectus.
Performance Availability Website Address [Text]	rr_PerformanceAvailabilityWebSiteAddress	www.greatwestfunds.com
Great-West Core Strategies: U.S. Equity Fund | Institutional Class
Risk/Return:	rr_RiskReturnAbstract
Maximum Sales Charge (Load) Imposed on Purchases (as a percentage of offering price)	rr_MaximumSalesChargeImposedOnPurchasesOverOfferingPrice	none
Maximum Deferred Sales Charge (Load)	rr_MaximumDeferredSalesChargeOverOther	none
Maximum Sales Charge (Load) Imposed on Reinvested Dividends	rr_MaximumSalesChargeOnReinvestedDividendsAndDistributionsOverOther	none
Redemption Fee	rr_RedemptionFeeOverRedemption	none
Exchange Fee	rr_ExchangeFeeOverRedemption	none
Management Fees	rr_ManagementFeesOverAssets	0.47%	[1]
Distribution and Service (12b-1) Fees	rr_DistributionAndService12b1FeesOverAssets	none	[1]
Other Expenses	rr_OtherExpensesOverAssets	0.13%	[1]
Acquired Fund Fees and Expenses	rr_AcquiredFundFeesAndExpensesOverAssets	0.01%	[1]
Total Annual Fund Operating Expenses	rr_ExpensesOverAssets	0.61%	[1]
Fee Waiver and Expense Reimbursement	rr_FeeWaiverOrReimbursementOverAssets	0.05%	[1],[2]
Total Annual Fund Operating Expenses After Fee Waiver and Expense Reimbursement	rr_NetExpensesOverAssets	0.56%	[1]
1 Year	rr_ExpenseExampleYear01	$ 58
3 Years	rr_ExpenseExampleYear03	$ 192

[1] Because the Fund has not yet commenced operations, "Other Expenses" and "Acquired Fund Fees" are based on estimated amounts for the current fiscal year.

[2] Great-West Capital Management, LLC ("GWCM"), the Fund's investment adviser, has contractually agreed to waive fees or reimburse expenses that exceed 0.55% of the Fund's average daily net assets, excluding acquired fund fees and expenses, brokerage expenses, taxes, dividend interest on short sales, interest expenses, and any extraordinary expenses, including litigation costs (the "Expense Limit"). The agreement's current term ends on August 28, 2019 and automatically renews for one-year terms unless it is terminated by the Fund or GWCM upon written notice within 90 days of the end of the current term or upon termination of the investment advisory agreement between the Fund and GWCM. Under the agreement, GWCM may recoup, subject to Board approval, these waivers and reimbursements in future periods, not exceeding three years following the particular waiver/reimbursement, provided Total Annual Fund Operating Expenses plus such recoupment do not exceed the lesser of the Expense Limit that was in place at the time of the waiver/reimbursement or the Expense Limit in place at the time of recoupment.

XML

Label	Element	Value
Risk/Return:	rr_RiskReturnAbstract
Registrant Name	dei_EntityRegistrantName	GREAT-WEST FUNDS INC
Prospectus Date	rr_ProspectusDate	Jun. 25, 2018
Document Creation Date	dei_DocumentCreationDate	Jun. 21, 2018