v3.26.1
Fees and Expenses
Mar. 31, 2026
Mercer US Small/Mid Cap Equity Fund | Mercer US Small/Mid Cap Equity Fund  
Prospectus [Line Items]  
Expense Heading [Optional Text] Fees and Expenses
Expense Narrative [Text Block]

These tables summarize the fees and expenses that you may pay if you buy, hold and sell shares of the Fund. You may pay other fees, such as brokerage commissions and other fees to financial intermediaries, which are not reflected in the tables and examples below.
Other Expenses, New Fund, Based on Estimates [Text] “Other Expenses” include administrative, custodial, legal, audit, transfer agent and Trustees’ fees and expenses. The “Other Expenses” shown for Adviser Class and Class Y-2 are based on estimated amounts for the Fund’s current fiscal year, as the Adviser Class and Class Y-2 shares of the Fund had not commenced operations prior to the most recent fiscal year end.
Expenses Not Correlated to Ratio Due to Acquired Fund Fees [Text] Total Annual Fund Operating Expenses and Net Annual Fund Operating Expenses do not correlate to the “total expenses (before reductions and reimbursements/waivers) to average daily net assets” and “net expenses to average daily net assets”, respectively, provided in the Financial Highlights. The information in the Financial Highlights does not include Acquired Fund Fees and Expenses, which are included above.
Shareholder Fees Caption [Optional Text] Shareholder Fees (fees paid directly from your investment)
Shareholder Fees [Table]
    Adviser
Class		   Class I   Class Y-2   Class Y-3
Redemption Fee on shares owned less than 30 days (as a % of total redemption proceeds)     2.00 %     2.00 %     2.00 %     2.00 %
Operating Expenses Caption [Optional Text] Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)
Annual Fund Operating Expenses [Table]
    Adviser
Class		   Class I   Class Y-2   Class Y-3
Management Fees(1),(2)     0.59 %     0.59 %     0.59 %     0.59 %
Distribution (12b-1) Fees     0.25 %     None       None       None  
Non-Distribution Shareholder Administrative Services Fees     0.25 %     0.25 %     0.15 %     None  
Other Expenses(3)     0.07 %     0.07 %     0.07 %     0.07 %
Acquired Fund Fees and Expenses     0.04 %     0.04 %     0.04 %     0.04 %
Total Annual Fund Operating Expenses(2),(4)     1.20 %     0.95 %     0.85 %     0.70 %
Less Fee Waivers(1)     -0.19 %     -0.19 %     -0.19 %     -0.19 %
Net Annual Fund Operating Expenses(4)     1.01 %     0.76 %     0.66 %     0.51 %
  
(1)Mercer Investments LLC (the “Adviser”) has contractually agreed, until at least July 31, 2027, to waive any portion of its management fee that exceeds the aggregate amount of the subadvisory fees that the Adviser is required to pay to the Fund’s subadvisers. This contractual fee waiver agreement may only be changed or eliminated with the approval of the Fund’s Board of Trustees. The fees waived by the Adviser pursuant to this agreement are not subject to reimbursement by the Fund to the Adviser. The amount of the fee waiver has been estimated to reflect the subadvisory fees in effect as of the date of this prospectus.
  
(2)The “Management Fees” and “Total Annual Fund Operating Expenses” have been adjusted to reflect the decrease in the management fee payable by the Portfolio from 0.87% to 0.59% effective as of July 1, 2026.
  
(3)“Other Expenses” include administrative, custodial, legal, audit, transfer agent and Trustees’ fees and expenses. The “Other Expenses” shown for Adviser Class and Class Y-2 are based on estimated amounts for the Fund’s current fiscal year, as the Adviser Class and Class Y-2 shares of the Fund had not commenced operations prior to the most recent fiscal year end.
  
(4)Total Annual Fund Operating Expenses and Net Annual Fund Operating Expenses do not correlate to the “total expenses (before reductions and reimbursements/waivers) to average daily net assets” and “net expenses to average daily net assets”, respectively, provided in the Financial Highlights. The information in the Financial Highlights does not include Acquired Fund Fees and Expenses, which are included above.
Expense Example [Heading] Example
Expense Example Narrative [Text Block]

The example below is intended to help you compare the costs 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 shown, that your investment has a 5% return each year, and that the Fund’s operating expenses remain the same as shown above (taking into account the contractual expense limitation being

in effect for the one-year period ending July 31, 2027).

Although your actual costs may be higher or lower, based on these assumptions, your costs would be:
Expense Example, With Redemption [Table]
   1 Year   3 Years   5 Years   10 Years 
Adviser Class  $103   $362   $641   $1,438 
Class I  $78   $284   $507   $1,149 
Class Y-2  $67   $252   $453   $1,031 
Class Y-3  $52   $205   $371   $853 
Portfolio Turnover [Heading] Portfolio Turnover
Portfolio Turnover [Text Block]

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 increase 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. During the most recent fiscal year, the Fund’s portfolio turnover rate was 59% of the average value of its portfolio.
Portfolio Turnover, Rate 59.00%
Mercer Non-US Core Equity Fund | Mercer Non-US Core Equity Fund  
Prospectus [Line Items]  
Expense Heading [Optional Text] Fees and Expenses
Expense Narrative [Text Block]

These tables summarize the fees and expenses that you may pay if you buy, hold and sell shares of the Fund. You may pay other fees, such as brokerage commissions and other fees to financial intermediaries, which are not reflected in the tables and examples below.
Other Expenses, New Fund, Based on Estimates [Text] “Other Expenses” include administrative, custodial, legal, audit, transfer agent and Trustees’ fees and expenses. The “Other Expenses” shown for Adviser Class and Class Y-2 are based on estimated amounts for the Fund’s current fiscal year, as the Adviser Class and Class Y-2 shares of the Fund had not commenced operations prior to the most recent fiscal year end.
Shareholder Fees Caption [Optional Text] Shareholder Fees (fees paid directly from your investment)
Shareholder Fees [Table]
    Adviser
Class		   Class I   Class Y-2   Class Y-3
Redemption Fee on shares owned less than 30 days (as a % of total redemption proceeds)     2.00 %     2.00 %     2.00 %     2.00 %
Operating Expenses Caption [Optional Text] Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)
Annual Fund Operating Expenses [Table]
    Adviser
Class		   Class I   Class Y-2   Class Y-3
Management Fees(1),(2)     0.54 %     0.54 %     0.54 %     0.54 %
Distribution (12b-1) Fees     0.25 %     None       None       None  
Non-Distribution Shareholder Administrative Services Fees     0.25 %     0.25 %     0.15 %     None  
Other Expenses(3)     0.06 %     0.06 %     0.06 %     0.06 %
Total Annual Fund Operating Expenses     1.10 %     0.85 %     0.75 %     0.60 %
Less Fee Waivers(1),(2)     -0.22 %     -0.22 %     -0.22 %     -0.22 %
Net Annual Fund Operating Expenses     0.88 %     0.63 %     0.53 %     0.38 %
(1)Mercer Investments LLC (the “Adviser”) has contractually agreed, until at least July 31, 2027, to waive any portion of its management fee that exceeds the aggregate amount of the subadvisory fees that the Adviser is required to pay to the Fund’s subadvisers. This contractual fee waiver agreement may only be changed or eliminated with the approval of the Fund’s Board of Trustees. The fees waived by the Adviser pursuant to this agreement are not subject to reimbursement by the Fund to the Adviser. The amount of the fee waiver has been estimated to reflect the subadvisory fees in effect as of the date of this prospectus.
  
(2)The “Management Fees” and “Total Annual Fund Operating Expenses” have been adjusted to reflect the decrease in the management fee payable by the Portfolio from 0.70% to 0.54% effective as of July 1, 2026.
  
(3)“Other Expenses” include administrative, custodial, legal, audit, transfer agent and Trustees’ fees and expenses. The “Other Expenses” shown for Adviser Class and Class Y-2 are based on estimated amounts for the Fund’s current fiscal year, as the Adviser Class and Class Y-2 shares of the Fund had not commenced operations prior to the most recent fiscal year end. The “Other Expenses” shown for Class I are also based on estimated amounts for the Fund’s current fiscal year.
Expense Example [Heading] Example
Expense Example Narrative [Text Block]

The example below is intended to help you compare the costs 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 shown, that your investment has a 5% return each year, and that the Fund’s operating expenses remain the same as shown above (taking into account the contractual expense limitation being in effect for the one-year period ending July 31, 2027).

Although your actual costs may be higher or lower, based on these assumptions, your costs would be:
Expense Example, With Redemption [Table]
    1 Year     3 Years     5 Years     10 Years  
Adviser Class   $ 90     $ 328     $ 585     $ 1,320  
Class I   $ 64     $ 249     $ 450     $ 1,029  
Class Y-2   $ 54     $ 218     $ 395     $ 910  
Class Y-3   $ 39     $ 170     $ 313     $ 729  
Portfolio Turnover [Heading] Portfolio Turnover
Portfolio Turnover [Text Block]

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 increase 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. During the most recent fiscal year, the Fund’s portfolio turnover rate was 67% of the average value of its portfolio.
Portfolio Turnover, Rate 67.00%
Mercer Emerging Markets Equity Fund | Mercer Emerging Markets Equity Fund  
Prospectus [Line Items]  
Expense Heading [Optional Text] Fees and Expenses
Expense Narrative [Text Block]

These tables summarize the fees and expenses that you may pay if you buy, hold and sell shares of the Fund. You may pay other fees, such as brokerage commissions and other fees to financial intermediaries, which are not reflected in the tables and examples below.
Other Expenses, New Fund, Based on Estimates [Text] “Other Expenses” include administrative, custodial, legal, audit, transfer agent and Trustees’ fees and expenses. The “Other Expenses” shown for Adviser Class and Class Y-2 are based on estimated amounts for the Fund’s current fiscal year, as the Adviser Class and Class Y-2 shares of the Fund had not commenced operations prior to the most recent fiscal year end.
Shareholder Fees Caption [Optional Text] Shareholder Fees (fees paid directly from your investment)
Shareholder Fees [Table]
    Adviser
Class		   Class I   Class Y-2   Class Y-3
Redemption Fee on shares owned less than 30 days (as a % of total redemption proceeds)     2.00 %     2.00 %     2.00 %     2.00 %
Operating Expenses Caption [Optional Text] Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)
Annual Fund Operating Expenses [Table]
    Adviser
Class		   Class I   Class Y-2   Class Y-3
Management Fees(1),(2)     0.56 %     0.56 %     0.56 %     0.56 %
Distribution (12b-1) Fees     0.25 %     None       None       None  
Non-Distribution Shareholder Administrative Services Fees     0.25 %     0.25 %     0.15 %     None  
Other Expenses(3)     0.09 %     0.09 %     0.09 %     0.09 %
Total Annual Fund Operating Expenses(2)     1.15 %     0.90 %     0.80 %     0.65 %
Less Fee Waivers(1)     -0.30 %      -0.30 %     -0.30 %     -0.30 %
Net Annual Fund Operating Expenses     0.85 %     0.60 %     0.50 %     0.35 %
(1)Mercer Investments LLC (the “Adviser”) has contractually agreed, until at least July 31, 2027, to waive any portion of its management fee that exceeds the aggregate amount of the subadvisory fees that the Adviser is required to pay to the Fund’s subadvisers. This contractual fee waiver agreement may only be changed or eliminated with the approval of the Fund’s Board of Trustees. The fees waived by the Adviser pursuant to this agreement are not subject to reimbursement by the Fund to the Adviser. The amount of the fee waiver has been estimated to reflect the subadvisory fees in effect as of the date of this prospectus.
  
(2)The “Management Fees” and “Total Annual Fund Operating Expenses” have been adjusted to reflect the decrease in the management fee payable by the Portfolio from 0.79% to 0.56% effective as of July 1, 2026.
  
(3)“Other Expenses” include administrative, custodial, legal, audit, transfer agent and Trustees’ fees and expenses. The “Other Expenses” shown for Adviser Class and Class Y-2 are based on estimated amounts for the Fund’s current fiscal year, as the Adviser Class and Class Y-2 shares of the Fund had not commenced operations prior to the most recent fiscal year end.
Expense Example [Heading] Example
Expense Example Narrative [Text Block]

The example below is intended to help you compare the costs 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 shown, that your investment has a 5% return each year, and that the Fund’s operating expenses remain the same as shown above (taking into account the contractual expense limitation being in effect for the one-year period ending July 31, 2027).

Although your actual costs may be higher or lower, based on these assumptions, your costs would be:
Expense Example, With Redemption [Table]
    1 Year     3 Years     5 Years     10 Years  
Adviser Class   $ 87     $ 336     $ 604     $ 1,371  
Class I   $ 61     $ 257     $ 469     $ 1,080  
Class Y-2   $ 51     $ 225     $ 415     $ 962  
Class Y-3   $ 36     $ 178     $ 332     $ 782  
Portfolio Turnover [Heading] Portfolio Turnover
Portfolio Turnover [Text Block]

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 increase 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. During the most recent fiscal year, the Fund’s portfolio turnover rate was 49% of the average value of its portfolio.
Portfolio Turnover, Rate 49.00%
Mercer Core Fixed Income Fund | Mercer Core Fixed Income Fund  
Prospectus [Line Items]  
Expense Heading [Optional Text] Fees and Expenses
Expense Narrative [Text Block]

These tables summarize the fees and expenses that you may pay if you buy, hold and sell shares of the Fund. You may pay other fees, such as brokerage commissions and other fees to financial intermediaries, which are not reflected in the tables and examples below.
Other Expenses, New Fund, Based on Estimates [Text] “Other Expenses” include administrative, custodial, legal, audit, transfer agent and Trustees’ fees and expenses. The “Other Expenses” shown for Adviser Class and Class Y-2 are based on estimated amounts for the Fund’s current fiscal year, as the Adviser Class and Class Y-2 shares of the Fund had not commenced operations prior to the most recent fiscal year end.
Shareholder Fees Caption [Optional Text] Shareholder Fees (fees paid directly from your investment)
Shareholder Fees [Table]
    Adviser
Class		   Class I   Class Y-2   Class Y-3
Redemption Fee on shares owned less than 30 days (as a % of total redemption proceeds)     2.00 %     2.00 %     2.00 %     2.00 %
                                 
Operating Expenses Caption [Optional Text] Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)
Annual Fund Operating Expenses [Table]
    Adviser
Class		   Class I   Class Y-2   Class Y-3
Management Fees(1),(2)     0.27 %     0.27 %      0.27 %     0.27 %
Distribution (12b-1) Fees     0.25 %     None       None       None  
Non-Distribution Shareholder Administrative Services Fees     0.25 %     0.25 %     0.15 %     None  
Other Expenses(3)     0.07 %     0.07 %     0.07 %     0.07 %
Total Annual Fund Operating Expenses(2)     0.84 %     0.59 %     0.49 %     0.34 %
Less Fee Waivers(1)     -0.19 %     -0.19 %     -0.19 %     -0.19 %
Net Annual Fund Operating Expenses     0.65 %     0.40 %     0.30 %     0.15 %
(1)Mercer Investments LLC (the “Adviser”) has contractually agreed, until at least July 31, 2027, to waive any portion of its management fee that exceeds the aggregate amount of the subadvisory fees that the Adviser is required to pay to the Fund’s subadvisers. This contractual fee waiver agreement may only be changed or eliminated with the approval of the Fund’s Board of Trustees. The fees waived by the Adviser pursuant to this agreement are not subject to reimbursement by the Fund to the Adviser. The amount of the fee waiver has been estimated to reflect the subadvisory fees in effect as of the date of this prospectus.
 
(2)The “Management Fees” and “Total Annual Fund Operating Expenses” have been adjusted to reflect the decrease in the management fee payable by the Portfolio from 0.31% to 0.27% effective as of July 1, 2026.
  
(3)“Other Expenses” include administrative, custodial, legal, audit, transfer agent and Trustees’ fees and expenses. The “Other Expenses” shown for Adviser Class and Class Y-2 are based on estimated amounts for the Fund’s current fiscal year, as the Adviser Class and Class Y-2 shares of the Fund had not commenced operations prior to the most recent fiscal year end.
Expense Example [Heading] Example
Expense Example Narrative [Text Block]

The example below is intended to help you compare the costs 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 shown, that your investment has a 5% return each year, and that the Fund’s operating expenses remain the same as shown above (taking into account the contractual expense limitation being in effect for the one-year period ending July 31, 2027).

Although your actual costs may be higher or lower, based on these assumptions, your costs would be:
Expense Example, With Redemption [Table]
    1 Year     3 Years     5 Years     10 Years  
Adviser Class   $ 66     $ 249     $ 447     $ 1,020  
Class I   $ 41     $ 170     $ 310     $ 720  
Class Y-2   $ 31     $ 138     $ 255     $ 598  
Class Y-3   $ 15     $ 90     $ 172     $ 412  
Portfolio Turnover [Heading] Portfolio Turnover
Portfolio Turnover [Text Block]

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 increase 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. During the most recent fiscal year, the Fund’s portfolio turnover rate was 125% of the average value of its portfolio.
Portfolio Turnover, Rate 125.00%
Mercer Opportunistic Fixed Income Fund | Mercer Opportunistic Fixed Income Fund  
Prospectus [Line Items]  
Expense Heading [Optional Text] Fees and Expenses
Expense Narrative [Text Block]

These tables summarize the fees and expenses that you may pay if you buy, hold and sell shares of the Fund. You may pay other fees, such as brokerage commissions and other fees to financial intermediaries, which are not reflected in the tables and examples below.
Other Expenses, New Fund, Based on Estimates [Text] “Other Expenses” include administrative, custodial, legal, audit, transfer agent and Trustees’ fees and expenses. The “Other Expenses” shown for Adviser Class and Class Y-2 are based on estimated amounts for the Fund’s current fiscal year, as the Adviser Class and Class Y-2 shares of the Fund had not commenced operations prior to the most recent fiscal year end.
Expenses Not Correlated to Ratio Due to Acquired Fund Fees [Text] Total Annual Fund Operating Expenses and Net Annual Fund Operating Expenses do not correlate to the “total expenses (before reductions and reimbursements/waivers) to average daily net assets” and “net expenses to average daily net assets”, respectively, provided in the Financial Highlights. The information in the Financial Highlights does not include AFFE, which are included above.
Shareholder Fees Caption [Optional Text] Shareholder Fees (fees paid directly from your investment)
Shareholder Fees [Table]
    Adviser
Class		   Class I   Class Y-2   Class Y-3
Redemption Fee on shares owned less than 30 days (as a % of total redemption proceeds)     2.00 %     2.00 %     2.00 %     2.00 %
                                 
Operating Expenses Caption [Optional Text] Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)
Annual Fund Operating Expenses [Table]
    Adviser
Class		   Class I   Class Y-2   Class Y-3
Management Fees(1),(2)     0.53 %     0.53 %     0.53 %     0.53 %
Distribution (12b-1) Fees     0.25 %     None       None       None  
Non-Distribution Shareholder Administrative Services Fees     0.25 %     0.25 %     0.15 %     None  
Other Expenses(3)     0.08 %     0.08 %     0.08 %     0.08 %
Acquired Fund Fees and Expenses(4)     0.07 %     0.07 %     0.07 %     0.07 %
Total Annual Fund Operating Expenses(2),(5)     1.18 %     0.93 %     0.83 %     0.68 %
Less Fee Waivers(1)     -0.18 %     -0.18 %     -0.18 %     -0.18 %
Net Annual Fund Operating Expenses(5)     1.00 %     0.75 %     0.65 %     0.50 %
(1)Mercer Investments LLC (the “Adviser”) has contractually agreed, until at least July 31, 2027, to waive any portion of its management fee that exceeds the aggregate amount of the subadvisory fees that the Adviser is required to pay to the Fund’s subadvisers. This contractual fee waiver agreement may only be changed or eliminated with the approval of the Fund’s Board of Trustees. The fees waived by the Adviser pursuant to this agreement are not subject to reimbursement by the Fund to the Adviser. The amount of the fee waiver has been estimated to reflect the subadvisory fees in effect as of the date of this prospectus.
  
(2)The “Management Fees” and “Total Annual Fund Operating Expenses” have been adjusted to reflect the decrease in the management fee payable by the Portfolio from 0.76% to 0.53% effective as of July 1, 2026.
  
(3)“Other Expenses” include administrative, custodial, legal, audit, transfer agent and Trustees’ fees and expenses. The “Other Expenses” shown for Adviser Class and Class Y-2 are based on estimated amounts for the Fund’s current fiscal year, as the Adviser Class and Class Y-2 shares of the Fund had not commenced operations prior to the most recent fiscal year end.
  
(4)Acquired Fund Fees and Expenses (“AFFE”) are indirect fees and expenses that the Fund incurs from investing in the shares of other funds, including business development companies. AFFE are based on estimated amounts for the current fiscal year.
  
(5)Total Annual Fund Operating Expenses and Net Annual Fund Operating Expenses do not correlate to the “total expenses (before reductions and reimbursements/waivers) to average daily net assets” and “net expenses to average daily net assets”, respectively, provided in the Financial Highlights. The information in the Financial Highlights does not include AFFE, which are included above.
Expense Example [Heading] Example
Expense Example Narrative [Text Block]

The example below is intended to help you compare the costs 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 shown, that your investment has a 5% return each year,

and that the Fund’s operating expenses remain the same as shown above (taking into account the contractual expense limitation being in effect for the one-year period ending July 31, 2027).

Although your actual costs may be higher or lower, based on these assumptions, your costs would be:
Expense Example, With Redemption [Table]
    1 Year     3 Years     5 Years     10 Years  
Adviser Class   $ 102     $ 357     $ 632     $ 1,416  
Class I   $ 77     $ 278     $ 497     $ 1,127  
Class Y-2   $ 66     $ 247     $ 443     $ 1,009  
Class Y-3   $ 51     $ 199     $ 361     $ 830  
Portfolio Turnover [Heading] Portfolio Turnover
Portfolio Turnover [Text Block]

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 increase 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. During the most recent fiscal year, the Fund’s portfolio turnover rate was 246% of the average value of its portfolio.
Portfolio Turnover, Rate 246.00%
Mercer Short Duration Fixed Income Fund | Mercer Short Duration Fixed Income Fund  
Prospectus [Line Items]  
Expense Heading [Optional Text] Fees and Expenses
Expense Narrative [Text Block]

These tables summarize the fees and expenses that you may pay if you invest in the Fund.
Other Expenses, New Fund, Based on Estimates [Text] “Other Expenses” include administrative, custodial, legal, audit, transfer agent and Trustees’ fees and expenses. The “Other Expenses” shown for Adviser Class and Class Y-2 are based on estimated amounts for the Fund’s current fiscal year, as the Adviser Class and Class Y-2 shares of the Fund had not commenced operations prior to the most recent fiscal year end. The “Other Expenses” shown for Class I are also based on estimated amounts for the Fund’s current fiscal year.
Shareholder Fees Caption [Optional Text] Shareholder Fees (fees paid directly from your investment)
Shareholder Fees [Table]
   Adviser Class  Class I  Class Y-2  Class Y-3
Redemption Fee on shares owned less than 30 days (as a % of total redemption proceeds)   2.00%       2.00%   2.00%   2.00%
Operating Expenses Caption [Optional Text] Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)
Annual Fund Operating Expenses [Table]
   Adviser Class  Class I  Class Y-2  Class Y-3
Management Fees(1),(2)   0.29%        0.29%   0.29%   0.29%
Distribution (12b-1) Fees   0.25%   None    None    None 
Non-Distribution Shareholder Administrative Services Fees   0.25%   0.25%   0.15%   None 
Other Expenses(3)   0.31%   0.31%   0.31%   0.31%
Total Annual Fund Operating Expenses(2)   1.10%   0.85%   0.75%   0.60%
Less Fee Waivers(1)(4)   -0.40%   -0.40%   -0.40%   -0.40%
Net Annual Fund Operating Expenses   0.70%   0.45%   0.35%   0.20%
(1)Mercer Investments LLC (the “Adviser”) has contractually agreed, until at least July 31, 2027, to waive any portion of its management fee that exceeds the aggregate amount of the subadvisory fees that the Adviser is required to pay to the Fund’s subadvisers. This contractual fee waiver agreement may only be changed or eliminated with the approval of the Fund’s Board of Trustees. The fees waived by the Adviser pursuant to this agreement are not subject to reimbursement by the Fund to the Adviser. The amount of the fee waiver has been estimated to reflect the subadvisory fees in effect as of the date of this prospectus.
  
(2)The “Management Fees” and “Total Annual Fund Operating Expenses” have been adjusted to reflect the decrease in the management fee payable by the Portfolio from 0.30% to 0.29% effective as of July 1, 2026.
  
(3)“Other Expenses” include administrative, custodial, legal, audit, transfer agent and Trustees’ fees and expenses. The “Other Expenses” shown for Adviser Class and Class Y-2 are based on estimated amounts for the Fund’s current fiscal year, as the Adviser Class and Class Y-2 shares of the Fund had not commenced operations prior to the most recent fiscal year end. The “Other Expenses” shown for Class I are also based on estimated amounts for the Fund’s current fiscal year.
  
(4)The Adviser has also contractually agreed, until at least July 31, 2027, to waive fees and/or reimburse Fund expenses to the extent that annual fund operating expenses, net of the management fee waiver described in footnote (1) above, exceed 0.70% for Adviser Class shares, 0.45% for Class I shares, 0.35% for Class Y-2 shares and 0.20% for Class Y-3 shares, excluding, as applicable, acquired fund fees and expenses, interest, taxes, 12b-1 fees, non-12b-1 shareholder administrative services fees, brokerage expenses, dividend and interest expenses on securities sold short, extraordinary expenses and other expenses not incurred in the ordinary course of the Fund’s business. This contractual fee waiver and reimbursement agreement cannot be eliminated prior to July 31, 2027 without the approval of the Fund’s Board of Trustees. The fees waived by the Adviser pursuant to this agreement are not subject to reimbursement by the Fund to the Adviser.
Expense Example [Heading] Example
Expense Example Narrative [Text Block]

The example below is intended to help you compare the costs 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 shown, that your investment has a 5% return each year, and that the Fund’s operating expenses remain the same as shown above (taking into account the contractual expense limitation being in effect for the one-year period ending July 31, 2027).

Although your actual costs may be higher or lower, based on these assumptions, your costs would be:
Expense Example, With Redemption [Table]
    1 Year     3 Years     5 Years     10 Years  
Adviser Class   $ 72     $ 310     $ 567     $ 1,304  
Class I   $ 46     $ 231     $ 432     $ 1,012  
Class Y-2   $ 36     $ 200     $ 377     $ 893  
Class Y-3   $ 20     $ 152     $ 295     $ 712  
Portfolio Turnover [Heading] Portfolio Turnover
Portfolio Turnover [Text Block]

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 increase 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. During the most recent fiscal year, the Fund’s portfolio turnover rate was 166% of the average value of its portfolio.
Portfolio Turnover, Rate 166.00%