v3.26.1
Performance Management
Apr. 30, 2026
Large Company Growth Portfolio  
Prospectus [Line Items]  
Bar Chart and Performance Table [Heading] Past Performance
Performance Narrative [Text Block]
The bar chart and the performance table below provide an indication of the risks of investing in the Portfolio by showing how the investment performance of the Investment Class Shares has varied from year to year and by showing how the Portfolio’s average annual total returns compare to those of a broad measure of market performance, as well as an additional index with investment characteristics similar to those of the Fund. The chart and table assume reinvestment of dividends and distributions. The Portfolio’s past investment performance (before and after taxes) does not necessarily indicate how it will perform in the future. For more recent performance figures, go to http://wilshire.com (the website does not form a part of this prospectus) or call 1-866-591-1568.
On July 21, 2020, the Portfolio’s investment strategy was changed. Consequently, prior period performance may have been different if the new investment strategy had been in effect during these periods.
Performance Past Does Not Indicate Future [Text] The Portfolio’s past investment performance (before and after taxes) does not necessarily indicate how it will perform in the future.
Performance Information Illustrates Variability of Returns [Text] The bar chart and the performance table below provide an indication of the risks of investing in the Portfolio by showing how the investment performance of the Investment Class Shares has varied from year to year and by showing how the Portfolio’s average annual total returns compare to those of a broad measure of market performance, as well as an additional index with investment characteristics similar to those of the Fund.
Performance Additional Market Index [Text] The bar chart and the performance table below provide an indication of the risks of investing in the Portfolio by showing how the investment performance of the Investment Class Shares has varied from year to year and by showing how the Portfolio’s average annual total returns compare to those of a broad measure of market performance, as well as an additional index with investment characteristics similar to those of the Fund.
Bar Chart [Heading] Calendar Year Returns
Bar Chart Closing [Text Block]
During the periods shown in the bar chart, the highest return for a quarter was 27.49% (quarter ended June 30, 2020) and the lowest return for a quarter was -20.91% (quarter ended June 30, 2022).
The returns for the Portfolio’s Investment Class shares were lower than the Institutional Class Shares because Investment Class Shares pay distribution (12b-1) fees.
Performance Table Heading Average Annual Total Returns (periods ended December 31, 2025)
Performance Table Uses Highest Federal Rate After-tax returns are calculated using the historical highest individual federal marginal income tax rates for each year in the period and do not reflect the impact of state and local taxes.
Performance Table Not Relevant to Tax Deferred The after-tax returns shown are not relevant to investors who are tax exempt or hold their Portfolio shares through tax-advantaged arrangements such as 401(k) plans or individual retirement accounts.
Performance Table One Class of after Tax Shown [Text] After-tax returns are shown for only Investment Class Shares. After-tax returns for Institutional Class Shares will vary.
Index No Deduction for Fees, Expenses, or Taxes [Text] (reflects no deduction for fees, expenses or taxes)
Performance Table Closing [Text Block]
After-tax returns are calculated using the historical highest individual federal marginal income tax rates for each year in the period and do not reflect the impact of state and local taxes. Actual after-tax returns depend on an investor’s tax situation and may differ from those shown. The after-tax returns shown are not relevant to investors who are tax exempt or hold their Portfolio shares through tax-advantaged arrangements such as 401(k) plans or individual retirement accounts.
After-tax returns are shown for only Investment Class Shares. After-tax returns for Institutional Class Shares will vary.
Performance Availability Website Address [Text] http://wilshire.com
Performance Availability Phone [Text] 1-866-591-1568
Large Company Growth Portfolio | Large Company Growth Portfolio - Investment Class  
Prospectus [Line Items]  
Highest Quarterly Return, Label [Optional Text] highest return for a quarter
Highest Quarterly Return 27.49%
Highest Quarterly Return, Date Jun. 30, 2020
Lowest Quarterly Return, Label [Optional Text] lowest return for a quarter
Lowest Quarterly Return (20.91%)
Lowest Quarterly Return, Date Jun. 30, 2022
Large Company Value Portfolio Series  
Prospectus [Line Items]  
Bar Chart and Performance Table [Heading] Past Performance
Performance Narrative [Text Block]
The bar chart and the performance table below provide an indication of the risks of investing in the Portfolio by showing how the investment performance of the Investment Class Shares has varied from year to year and by showing how the Portfolio’s average annual total returns compare to those of a broad measure of market performance, as well as an additional index with investment characteristics similar to those of the Fund. The chart and table assume reinvestment of dividends and distributions. The Portfolio’s past investment performance (before and after taxes) does not necessarily indicate how it will perform in the future. For more recent performance figures, go to http://wilshire.com (the website does not form a part of this prospectus) or call 1-866-591-1568.
On July 21, 2020, the Portfolio’s investment strategy was changed. Consequently, prior period performance may have been different if the new investment strategy had been in effect during these periods.
Performance Past Does Not Indicate Future [Text] The Portfolio’s past investment performance (before and after taxes) does not necessarily indicate how it will perform in the future.
Performance Information Illustrates Variability of Returns [Text] The bar chart and the performance table below provide an indication of the risks of investing in the Portfolio by showing how the investment performance of the Investment Class Shares has varied from year to year and by showing how the Portfolio’s average annual total returns compare to those of a broad measure of market performance, as well as an additional index with investment characteristics similar to those of the Fund.
Performance Additional Market Index [Text] The bar chart and the performance table below provide an indication of the risks of investing in the Portfolio by showing how the investment performance of the Investment Class Shares has varied from year to year and by showing how the Portfolio’s average annual total returns compare to those of a broad measure of market performance, as well as an additional index with investment characteristics similar to those of the Fund.
Bar Chart [Heading] Calendar Year Returns
Bar Chart Closing [Text Block]
During the periods shown in the bar chart, the highest return for a quarter was 21.04% (quarter ended December 31, 2020) and the lowest return for a quarter was -31.03% (quarter ended March 31, 2020).
The returns for the Portfolio’s Investment Class shares were lower than the Institutional Class Shares because Investment Class Shares pay distribution (12b-1) fees.
Performance Table Heading Average Annual Total Returns (periods ended December 31, 2025)
Performance Table Uses Highest Federal Rate After-tax returns are calculated using the historical highest individual federal marginal income tax rates for each year in the period and do not reflect the impact of state and local taxes.
Performance Table Not Relevant to Tax Deferred Actual after-tax returns depend on an investor’s tax situation and may differ from those shown. The after-tax returns shown are not relevant to investors who are tax exempt or hold their Portfolio shares through tax-advantaged arrangements such as 401(k) plans or individual retirement accounts.
Performance Table One Class of after Tax Shown [Text] After-tax returns are shown for only Investment Class Shares. After-tax returns for Institutional Class Shares will vary.
Index No Deduction for Fees, Expenses, or Taxes [Text] (reflects no deduction for fees, expenses or taxes)
Performance Table Closing [Text Block]
After-tax returns are calculated using the historical highest individual federal marginal income tax rates for each year in the period and do not reflect the impact of state and local taxes. Actual after-tax returns depend on an investor’s tax situation and may differ from those shown. The after-tax returns shown are not relevant to investors who are tax exempt or hold their Portfolio shares through tax-advantaged arrangements such as 401(k) plans or individual retirement accounts.
After-tax returns are shown for only Investment Class Shares. After-tax returns for Institutional Class Shares will vary.
Performance Availability Website Address [Text] http://wilshire.com
Performance Availability Phone [Text] 1-866-591-1568
Large Company Value Portfolio Series | Large Company Value Portfolio - Investment Class  
Prospectus [Line Items]  
Highest Quarterly Return, Label [Optional Text] highest return for a quarter
Highest Quarterly Return 21.04%
Highest Quarterly Return, Date Dec. 31, 2020
Lowest Quarterly Return, Label [Optional Text] lowest return for a quarter
Lowest Quarterly Return (31.03%)
Lowest Quarterly Return, Date Mar. 31, 2020
Small Company Growth Portfolio Series  
Prospectus [Line Items]  
Bar Chart and Performance Table [Heading] Past Performance
Performance Narrative [Text Block]
The bar chart and the performance table below provide an indication of the risks of investing in the Portfolio by showing how the investment performance of the Investment Class Shares has varied from year to year and by showing how the Portfolio’s average annual total returns compare to those of a broad measure of market performance as well as an additional index with investment characteristics similar to those of the Fund. The chart and table assume reinvestment of dividends and distributions. The Portfolio’s past investment performance (before and after taxes) does not necessarily indicate how it will perform in the future. For more recent performance figures, go to http://wilshire.com (the website does not form a part of this prospectus) or call 1-866-591-1568.
Performance Past Does Not Indicate Future [Text] The Portfolio’s past investment performance (before and after taxes) does not necessarily indicate how it will perform in the future.
Performance Information Illustrates Variability of Returns [Text] The bar chart and the performance table below provide an indication of the risks of investing in the Portfolio by showing how the investment performance of the Investment Class Shares has varied from year to year and by showing how the Portfolio’s average annual total returns compare to those of a broad measure of market performance as well as an additional index with investment characteristics similar to those of the Fund.
Performance Additional Market Index [Text] The bar chart and the performance table below provide an indication of the risks of investing in the Portfolio by showing how the investment performance of the Investment Class Shares has varied from year to year and by showing how the Portfolio’s average annual total returns compare to those of a broad measure of market performance as well as an additional index with investment characteristics similar to those of the Fund.
Bar Chart [Heading] Calendar Year Returns
Bar Chart Closing [Text Block]
During the periods shown in the bar chart, the highest return for a quarter was 27.07% (quarter ended June 30, 2020) and the lowest return for a quarter was -24.03% (quarter ended March 31, 2020).
The returns for the Portfolio’s Investment Class shares were lower than the Institutional Class Shares because Investment Class Shares pay distribution (12b-1) fees.
Performance Table Heading Average Annual Total Returns (periods ended December 31, 2025)
Performance Table Uses Highest Federal Rate After-tax returns are calculated using the historical highest individual federal marginal income tax rates for each year in the period and do not reflect the impact of state and local taxes.
Performance Table Not Relevant to Tax Deferred The after-tax returns shown are not relevant to investors who are tax exempt or hold their Portfolio shares through tax-advantaged arrangements such as 401(k) plans or individual retirement accounts.
Performance Table Explanation after Tax Higher In certain cases, the figure representing “Return After Taxes on Distributions and Sale of Shares” may be higher than the other return figures of the same period. A higher after-tax return results when a capital loss occurs upon redemption and provides an assumed tax deduction that benefits the investor.
Performance Table One Class of after Tax Shown [Text] After-tax returns are shown for only Investment Class Shares. After-tax returns for Institutional Class Shares will vary.
Index No Deduction for Fees, Expenses, or Taxes [Text] (reflects no deduction for fees, expenses or taxes)
Performance Table Closing [Text Block] In certain cases, the figure representing “Return After Taxes on Distributions and Sale of Shares” may be higher than the other return figures of the same period. A higher after-tax return results when a capital loss occurs upon redemption and provides an assumed tax deduction that benefits the investor.
After-tax returns are calculated using the historical highest individual federal marginal income tax rates for each year in the period and do not reflect the impact of state and local taxes. Actual after-tax returns depend on an investor’s tax situation and may differ from those shown. The after-tax returns shown are not relevant to investors who are tax exempt or hold their Portfolio shares through tax-advantaged arrangements such as 401(k) plans or individual retirement accounts.
After-tax returns are shown for only Investment Class Shares. After-tax returns for Institutional Class Shares will vary.
Performance Availability Website Address [Text] http://wilshire.com
Performance Availability Phone [Text] 1-866-591-1568
Small Company Growth Portfolio Series | Small Company Growth Portfolio - Investment Class  
Prospectus [Line Items]  
Highest Quarterly Return, Label [Optional Text] highest return for a quarter
Highest Quarterly Return 27.07%
Highest Quarterly Return, Date Jun. 30, 2020
Lowest Quarterly Return, Label [Optional Text] lowest return for a quarter
Lowest Quarterly Return (24.03%)
Lowest Quarterly Return, Date Mar. 31, 2020
Small Company Value Portfolio  
Prospectus [Line Items]  
Bar Chart and Performance Table [Heading] Past Performance
Performance Narrative [Text Block]
The bar chart and the performance table below provide an indication of the risks of investing in the Portfolio by showing how the investment performance of the Investment Class Shares has varied from year to year and by showing how the Portfolio’s average annual total returns compare to those of a broad measure of market performance, as well as an additional index with investment characteristics similar to those of the Fund. The chart and table assume reinvestment of dividends and distributions. The Portfolio’s past investment performance (before and after taxes) does not necessarily indicate how it will perform in the future. For more recent performance figures, go to http://wilshire.com (the website does not form a part of this prospectus) or call 1-866-591-1568.
Performance Past Does Not Indicate Future [Text] The Portfolio’s past investment performance (before and after taxes) does not necessarily indicate how it will perform in the future.
Performance Information Illustrates Variability of Returns [Text] The bar chart and the performance table below provide an indication of the risks of investing in the Portfolio by showing how the investment performance of the Investment Class Shares has varied from year to year and by showing how the Portfolio’s average annual total returns compare to those of a broad measure of market performance, as well as an additional index with investment characteristics similar to those of the Fund.
Performance Additional Market Index [Text] The bar chart and the performance table below provide an indication of the risks of investing in the Portfolio by showing how the investment performance of the Investment Class Shares has varied from year to year and by showing how the Portfolio’s average annual total returns compare to those of a broad measure of market performance, as well as an additional index with investment characteristics similar to those of the Fund.
Bar Chart [Heading] Calendar Year Returns
Bar Chart Closing [Text Block]
During the periods shown in the bar chart, the highest return for a quarter was 32.25% (quarter ended December 31, 2020) and the lowest return for a quarter was -37.30% (quarter ended March 31, 2020).
The returns for the Portfolio’s Investment Class shares were lower than the Institutional Class Shares because Investment Class Shares pay distribution (12b-1) fees.
Performance Table Heading Average Annual Total Returns (periods ended December 31, 2025)
Performance Table Uses Highest Federal Rate After-tax returns are calculated using the historical highest individual federal marginal income tax rates for each year in the period and do not reflect the impact of state and local taxes.
Performance Table Not Relevant to Tax Deferred The after-tax returns shown are not relevant to investors who are tax exempt or hold their Portfolio shares through tax-advantaged arrangements such as 401(k) plans or individual retirement accounts.
Performance Table Explanation after Tax Higher In certain cases, the figure representing “Return After Taxes on Distributions and Sale of Shares” may be higher than the other return figures of the same period. A higher after-tax return results when a capital loss occurs upon redemption and provides an assumed tax deduction that benefits the investor.
Performance Table One Class of after Tax Shown [Text] After-tax returns are shown for only Investment Class Shares. After-tax returns for Institutional Class Shares will vary.
Index No Deduction for Fees, Expenses, or Taxes [Text] (reflects no deduction for fees, expenses or taxes)
Performance Table Closing [Text Block]
(1) In certain cases, the figure representing “Return After Taxes on Distributions and Sale of Shares” may be higher than the other return figures of the same period. A higher after-tax return results when a capital loss occurs upon redemption and provides an assumed tax deduction that benefits the investor.
After-tax returns are calculated using the historical highest individual federal marginal income tax rates for each year in the period and do not reflect the impact of state and local taxes. Actual after-tax returns depend on an investor’s tax situation and may differ from those shown. The after-tax returns shown are not relevant to investors who are tax exempt or hold their Portfolio shares through tax-advantaged arrangements such as 401(k) plans or individual retirement accounts.
After-tax returns are shown for only Investment Class Shares. After-tax returns for Institutional Class Shares will vary.
Performance Availability Website Address [Text] http://wilshire.com
Performance Availability Phone [Text] 1-866-591-1568
Small Company Value Portfolio | Small Company Value Portfolio - Investment Class  
Prospectus [Line Items]  
Highest Quarterly Return, Label [Optional Text] highest return for a quarter
Highest Quarterly Return 32.25%
Highest Quarterly Return, Date Dec. 31, 2020
Lowest Quarterly Return, Label [Optional Text] lowest return for a quarter
Lowest Quarterly Return (37.30%)
Lowest Quarterly Return, Date Mar. 31, 2020
Wilshire 5000 IndexSM Fund  
Prospectus [Line Items]  
Bar Chart and Performance Table [Heading] Past Performance
Performance Narrative [Text Block]
The bar chart and the performance table below provide an indication of the risks of investing in the Index Fund by showing how the investment performance of the Investment Class Shares has varied from year to year and by showing how the Index Fund’s average annual total returns compare to those of a broad measure of market performance. The chart and table assume reinvestment of dividends and distributions. The Index Fund’s past investment performance (before and after taxes) does not necessarily indicate how it will perform in the future. For more recent performance figures, go to http://wilshire.com (the website does not form a part of this prospectus) or call 1-866-591-1568.
Performance Past Does Not Indicate Future [Text] The Index Fund’s past investment performance (before and after taxes) does not necessarily indicate how it will perform in the future.
Performance Information Illustrates Variability of Returns [Text] The bar chart and the performance table below provide an indication of the risks of investing in the Index Fund by showing how the investment performance of the Investment Class Shares has varied from year to year and by showing how the Index Fund’s average annual total returns compare to those of a broad measure of market performance.
Bar Chart [Heading] Calendar Year Returns
Bar Chart Closing [Text Block]
During the periods shown in the bar chart, the highest return for a quarter was 21.41% (quarter ended June 30, 2020) and the lowest return for a quarter was -20.37% (quarter ended March 31, 2020).
The returns for the Index Fund’s Investment Class shares were lower than the Institutional Class Shares because Investment Class Shares pay distribution (12b-1) fees.
Performance Table Heading Average Annual Total Returns (periods ended December 31, 2025)
Performance Table Uses Highest Federal Rate After-tax returns are calculated using the historical highest individual federal marginal income tax rates for each year in the period and do not reflect the impact of state and local taxes.
Performance Table Not Relevant to Tax Deferred The after-tax returns shown are not relevant to investors who are tax exempt or hold their Index Fund shares through tax-advantaged arrangements such as 401(k) plans or individual retirement accounts.
Performance Table One Class of after Tax Shown [Text] After-tax returns are shown for only Investment Class Shares. After-tax returns for Institutional Class Shares will vary.
Index No Deduction for Fees, Expenses, or Taxes [Text] (reflects no deduction for fees, expenses or taxes)
Performance Table Closing [Text Block]
After-tax returns are calculated using the historical highest individual federal marginal income tax rates for each year in the period and do not reflect the impact of state and local taxes. Actual after-tax returns depend on an investor’s tax situation and may differ from those shown. The after-tax returns shown are not relevant to investors who are tax exempt or hold their Index Fund shares through tax-advantaged arrangements such as 401(k) plans or individual retirement accounts.
After-tax returns are shown for only Investment Class Shares. After-tax returns for Institutional Class Shares will vary.
Performance Availability Website Address [Text] http://wilshire.com
Performance Availability Phone [Text] 1-866-591-1568
Wilshire 5000 IndexSM Fund | Wilshire 5000 IndexSM Fund - Investment Class  
Prospectus [Line Items]  
Highest Quarterly Return, Label [Optional Text] highest return for a quarter
Highest Quarterly Return 21.41%
Highest Quarterly Return, Date Jun. 30, 2020
Lowest Quarterly Return, Label [Optional Text] lowest return for a quarter
Lowest Quarterly Return (20.37%)
Lowest Quarterly Return, Date Mar. 31, 2020
Wilshire International Equity Fund  
Prospectus [Line Items]  
Bar Chart and Performance Table [Heading] Past Performance
Performance Narrative [Text Block]
The bar chart and the performance table below provide an indication of the risks of investing in the International Fund by showing how the investment performance of the Investment Class Shares has varied from year to year and by showing how the International Fund’s average annual total returns compare to those of a broad measure of market performance. The chart and table assume reinvestment of dividends and distributions. The International Fund’s past investment performance (before and after taxes) does not necessarily indicate how it will perform in the future. For more recent performance figures, go to http://wilshire.com (the website does not form a part of this prospectus) or call 1-866-591-1568.
The International Fund’s investment strategy was changed on July 21, 2020. Consequently, prior period performance may have been different if the current investment strategy had been in effect during that period.
Performance Past Does Not Indicate Future [Text] The International Fund’s past investment performance (before and after taxes) does not necessarily indicate how it will perform in the future.
Performance Information Illustrates Variability of Returns [Text] The bar chart and the performance table below provide an indication of the risks of investing in the International Fund by showing how the investment performance of the Investment Class Shares has varied from year to year and by showing how the International Fund’s average annual total returns compare to those of a broad measure of market performance.
Bar Chart [Heading] Calendar Year Returns
Bar Chart Closing [Text Block]
During the periods shown in the bar chart, the highest return for a quarter was 21.32% (quarter ended June 30, 2020) and the lowest return for a quarter was -24.10% (quarter ended March 31, 2020).
The returns for the International Fund’s Investment Class shares were lower than the Institutional Class Shares because Investment Class Shares pay distribution (12b-1) fees.
Performance Table Heading Average Annual Total Returns (periods ended December 31, 2025)
Performance Table Uses Highest Federal Rate After-tax returns are calculated using the historical highest individual federal marginal income tax rates for each year in the period and do not reflect the impact of state and local taxes.
Performance Table Not Relevant to Tax Deferred The after-tax returns shown are not relevant to investors who are tax exempt or hold their International Fund shares through tax-advantaged arrangements such as 401(k) plans or individual retirement accounts.
Performance Table Explanation after Tax Higher In certain cases, the figure representing “Return After Taxes on Distributions and Sale of Shares” may be higher than the other return figures of the same period. A higher after-tax return results when a capital loss occurs upon redemption and provides an assumed tax deduction that benefits the investor.
Performance Table One Class of after Tax Shown [Text] After-tax returns are shown for only Investment Class Shares. After-tax returns for Institutional Class Shares will vary.
Index No Deduction for Fees, Expenses, or Taxes [Text] (reflects no deduction for fees, expenses and taxes)
Performance Table Closing [Text Block]
(1) In certain cases, the figure representing “Return After Taxes on Distributions and Sale of Shares” may be higher than the other return figures of the same period. A higher after-tax return results when a capital loss occurs upon redemption and provides an assumed tax deduction that benefits the investor.
After-tax returns are calculated using the historical highest individual federal marginal income tax rates for each year in the period and do not reflect the impact of state and local taxes. Actual after-tax returns depend on an investor’s tax situation and may differ from those shown. The after-tax returns shown are not relevant to investors who are tax exempt or hold their International Fund shares through tax-advantaged arrangements such as 401(k) plans or individual retirement accounts.
After-tax returns are shown for only Investment Class Shares. After-tax returns for Institutional Class Shares will vary.
Performance Availability Website Address [Text] http://wilshire.com
Performance Availability Phone [Text] 1-866-591-1568
Wilshire International Equity Fund | Wilshire International Equity Fund - Investment Class  
Prospectus [Line Items]  
Highest Quarterly Return, Label [Optional Text] highest return for a quarter
Highest Quarterly Return 21.32%
Highest Quarterly Return, Date Jun. 30, 2020
Lowest Quarterly Return, Label [Optional Text] lowest return for a quarter
Lowest Quarterly Return (24.10%)
Lowest Quarterly Return, Date Mar. 31, 2020
Wilshire Income Opportunities Fund  
Prospectus [Line Items]  
Bar Chart and Performance Table [Heading] Past Performance
Performance Narrative [Text Block]
The bar chart and the performance table below provide an indication of the risks of investing in the Income Fund by showing the investment performance of the Investment Class Shares during the most recent calendar year and by showing how the Income Fund’s average annual total returns compare to those of a broad measure of market performance, as well as an additional custom blended index that reflects the performance of the market sectors in which the Income Fund invests. The chart and table assume reinvestment of dividends and distributions. The Income Fund’s past investment performance (before and after taxes) does not necessarily indicate how it will perform in the future. For more recent performance figures, go to http://wilshire.com (the website does not form a part of this prospectus) or call 1-866-591-1568.
Performance Past Does Not Indicate Future [Text] The Income Fund’s past investment performance (before and after taxes) does not necessarily indicate how it will perform in the future.
Performance Information Illustrates Variability of Returns [Text] The bar chart and the performance table below provide an indication of the risks of investing in the Income Fund by showing the investment performance of the Investment Class Shares during the most recent calendar year and by showing how the Income Fund’s average annual total returns compare to those of a broad measure of market performance, as well as an additional custom blended index that reflects the performance of the market sectors in which the Income Fund invests.
Performance Additional Market Index [Text] The bar chart and the performance table below provide an indication of the risks of investing in the Income Fund by showing the investment performance of the Investment Class Shares during the most recent calendar year and by showing how the Income Fund’s average annual total returns compare to those of a broad measure of market performance, as well as an additional custom blended index that reflects the performance of the market sectors in which the Income Fund invests.
Bar Chart [Heading] Calendar Year Returns
Bar Chart Closing [Text Block]
During the periods shown in the bar chart, the highest return for a quarter was 6.54% (quarter ended June 30, 2020) and the lowest return for a quarter was -8.20% (quarter ended March 31, 2020).
The returns for the Income Fund’s Investment Class shares were lower than the Institutional Class Shares because Investment Class Shares pay distribution (12b-1) fees.
Performance Table Heading Average Annual Total Returns(periods ended December 31, 2025)
Performance Table Uses Highest Federal Rate After-tax returns are calculated using the historical highest individual federal marginal income tax rates for each year in the period and do not reflect the impact of state and local taxes.
Performance Table Not Relevant to Tax Deferred The after-tax returns shown are not relevant to investors who are tax exempt or hold their Income Fund shares through tax-advantaged arrangements such as 401(k) plans or individual retirement accounts.
Performance Table Explanation after Tax Higher In certain cases, the figure representing “Return After Taxes on Distributions and Sale of Shares” may be higher than the other return figures of the same period. A higher after-tax return results when a capital loss occurs upon redemption and provides an assumed tax deduction that benefits the investor.
Performance Table Footnotes In certain cases, the figure representing “Return After Taxes on Distributions and Sale of Shares” may be higher than the other return figures of the same period. A higher after-tax return results when a capital loss occurs upon redemption and provides an assumed tax deduction that benefits the investor.
(2)The Custom Blended Index consists of 70% Bloomberg U.S. Universal Index, 10% Bloomberg U.S. Corporate High Yield 2% Issuer Capped Bond Index, 10% S&P/LSTA Leveraged Loan Index, and 10% Bloomberg Emerging Markets USD Aggregate Bond Index.
Performance Table One Class of after Tax Shown [Text] After-tax returns are shown for only Investment Class Shares. After-tax returns for Institutional Class Shares will vary.
Index No Deduction for Fees, Expenses, or Taxes [Text] (reflects no deduction for fees, expenses and taxes)
Performance Table Closing [Text Block]
After-tax returns are calculated using the historical highest individual federal marginal income tax rates for each year in the period and do not reflect the impact of state and local taxes. Actual after-tax returns depend on an investor’s tax situation and may differ from those shown. The after-tax returns shown are not relevant to investors who are tax exempt or hold their Income Fund shares through tax-advantaged arrangements such as 401(k) plans or individual retirement accounts.
After-tax returns are shown for only Investment Class Shares. After-tax returns for Institutional Class Shares will vary.
Performance Availability Website Address [Text] http://wilshire.com
Performance Availability Phone [Text] 1-866-591-1568
Wilshire Income Opportunities Fund | Wilshire Income Opportunities Fund - Investment Class  
Prospectus [Line Items]  
Highest Quarterly Return, Label [Optional Text] highest return for a quarter
Highest Quarterly Return 6.54%
Highest Quarterly Return, Date Jun. 30, 2020
Lowest Quarterly Return, Label [Optional Text] lowest return for a quarter
Lowest Quarterly Return (8.20%)
Lowest Quarterly Return, Date Mar. 31, 2020