v3.26.1
Shareholder Report
 6 Months Ended
Apr. 30, 2026
USD ($)
Holding
Shareholder Report [Line Items]  
Document Type N-CSRS
Amendment Flag false
Registrant Name GALLERY TRUST
Entity Central Index Key 0001651872
Entity Investment Company Type N-1A
Document Period End Date Apr. 30, 2026
C000162391  
Shareholder Report [Line Items]  
Fund Name Mondrian International Value Equity Fund
Class Name Institutional Shares
Trading Symbol MPIEX
Annual or Semi-Annual Statement [Text Block] Semi-Annual Shareholder Report
Shareholder Report Annual or Semi-Annual semi-annual shareholder report
Additional Information [Text Block] This semi-annual shareholder report contains important information about Institutional Shares of the Mondrian International Value Equity Fund (the "Fund") for the period from November 1, 2025 to April 30, 2026. You can find additional information about the Fund at https://www.mondrian.com/mutualfunds/international-value-equity-fund/. You can also request this information by contacting us at 888-832-4386.
Additional Information Phone Number 888-832-4386
Additional Information Website https://www.mondrian.com/mutualfunds/international-value-equity-fund/
Expenses [Text Block]

What were the Fund costs for the last six months?

(based on a hypothetical $10,000 investment) 

Table Summary
Fund Name
Costs of a $10,000 investment
Costs paid as a percentage of a $10,000 investment
Mondrian International Value Equity Fund, Institutional Shares
$39
0.74%
Expenses Paid, Amount $ 39
Expense Ratio, Percent 0.74%
AssetsNet $ 1,085,781,026
Holdings Count | Holding 51
Advisory Fees Paid, Amount $ 3,334,366
InvestmentCompanyPortfolioTurnover 14.00%
Additional Fund Statistics [Text Block]

Key Fund Statistics as of April 30, 2026

Table Summary
Total Net Assets
Number of Holdings
Total Advisory Fees Paid
Portfolio Turnover Rate
$1,085,781,026
51
$3,334,366
14%
Holdings [Text Block]

Country WeightingsFootnote Reference*

Group By Sector Chart
Table Summary
Value
Value
Other Countries
1.4%
Netherlands
1.6%
Finland
1.9%
Singapore
2.9%
Australia
3.0%
Switzerland
4.7%
Spain
4.7%
Italy
6.0%
Hong Kong
6.2%
Germany
9.8%
France
15.6%
United Kingdom
17.8%
Japan
23.1%
FootnoteDescription
Footnote*
Percentages are calculated based on total net assets.
Largest Holdings [Text Block]

Top Ten Holdings

Table Summary
Holding Name
Percentage of Total Net Assets
Panasonic Holdings Corp
3.7%
Nestle SA
3.2%
Allianz SE
3.1%
Banco Santander SA
3.0%
Lloyds Banking Group PLC
2.9%
United Overseas Bank Ltd
2.9%
Sanofi SA
2.9%
CK Hutchison Holdings Ltd
2.8%
Sony Group Corp
2.7%
Deutsche Post AG
2.6%
Updated Prospectus Phone Number 888-832-4386
Updated Prospectus Web Address https://www.mondrian.com/mutualfunds/international-value-equity-fund/
C000204585  
Shareholder Report [Line Items]  
Fund Name Mondrian Emerging Markets Value Equity Fund
Class Name Institutional Shares
Trading Symbol MPEMX
Annual or Semi-Annual Statement [Text Block] Semi-Annual Shareholder Report
Shareholder Report Annual or Semi-Annual semi-annual shareholder report
Additional Information [Text Block] This semi-annual shareholder report contains important information about Institutional Shares of the Mondrian Emerging Markets Value Equity Fund (the "Fund") for the period from November 1, 2025 to April 30, 2026. You can find additional information about the Fund at https://www.mondrian.com/mutualfunds/emerging-markets-value-equity-fund/. You can also request this information by contacting us at 888-832-4386.
Additional Information Phone Number 888-832-4386
Additional Information Website https://www.mondrian.com/mutualfunds/emerging-markets-value-equity-fund/
Expenses [Text Block]

What were the Fund costs for the last six months?

(based on a hypothetical $10,000 investment) 

Table Summary
Fund Name
Costs of a $10,000 investment
Costs paid as a percentage of a $10,000 investment
Mondrian Emerging Markets Value Equity Fund, Institutional Shares
$48
0.92%
Expenses Paid, Amount $ 48
Expense Ratio, Percent 0.92%
AssetsNet $ 22,015,442
Holdings Count | Holding 60
Advisory Fees Paid, Amount $ 26,321
InvestmentCompanyPortfolioTurnover 17.00%
Additional Fund Statistics [Text Block]

Key Fund Statistics as of April 30, 2026

Table Summary
Total Net Assets
Number of Holdings
Total Advisory Fees Paid
Portfolio Turnover Rate
$22,015,442
60
$26,321
17%
Holdings [Text Block]

Country WeightingsFootnote Reference*

Group By Sector Chart
Table Summary
Value
Value
Other Countries
7.0%
Malaysia
1.3%
United Kingdom
1.3%
Philippines
1.4%
United Arab Emirates
3.1%
Saudi Arabia
3.4%
Indonesia
3.5%
Mexico
3.7%
India
8.3%
Brazil
8.3%
South Korea
14.1%
Taiwan
19.1%
China
25.3%
FootnoteDescription
Footnote*
Percentages are calculated based on total net assets.
Largest Holdings [Text Block]

Top Ten Holdings

Table Summary
Holding Name
Percentage of Total Net Assets
Taiwan Semiconductor Manufacturing Co Ltd
12.6%
Samsung Electronics Co Ltd, Preference
6.7%
Tencent Holdings Ltd
3.2%
Alibaba Group Holding Ltd
3.2%
Hon Hai Precision Industry Co Ltd
3.1%
Petroleo Brasileiro SA ADR
2.8%
Shinhan Financial Group Co Ltd
2.6%
Vale Sponsored ADR, Cl B
2.2%
Bank Rakyat Indonesia Persero Tbk PT
2.1%
Itausa SA
2.1%
Updated Prospectus Phone Number 888-832-4386
Updated Prospectus Web Address https://www.mondrian.com/mutualfunds/emerging-markets-value-equity-fund/
C000206727  
Shareholder Report [Line Items]  
Fund Name Mondrian Global Listed Infrastructure Fund
Class Name Institutional Shares
Trading Symbol MGIFX
Annual or Semi-Annual Statement [Text Block] Semi-Annual Shareholder Report
Shareholder Report Annual or Semi-Annual semi-annual shareholder report
Additional Information [Text Block] This semi-annual shareholder report contains important information about Institutional Shares of the Mondrian Global Listed Infrastructure Fund (the "Fund") for the period from November 1, 2025 to April 30, 2026. You can find additional information about the Fund at https://www.mondrian.com/mutualfunds/global-listed-infrastructure-fund/. You can also request this information by contacting us at 888-832-4386.
Additional Information Phone Number 888-832-4386
Additional Information Website https://www.mondrian.com/mutualfunds/global-listed-infrastructure-fund/
Expenses [Text Block]

What were the Fund costs for the last six months?

(based on a hypothetical $10,000 investment) 

Table Summary
Fund Name
Costs of a $10,000 investment
Costs paid as a percentage of a $10,000 investment
Mondrian Global Listed Infrastructure Fund, Institutional Shares
$51
0.95%
Expenses Paid, Amount $ 51
Expense Ratio, Percent 0.95%
AssetsNet $ 2,747,110
Holdings Count | Holding 25
Advisory Fees Paid, Amount $ 0
InvestmentCompanyPortfolioTurnover 14.00%
Additional Fund Statistics [Text Block]

Key Fund Statistics as of April 30, 2026

Table Summary
Total Net Assets
Number of Holdings
Total Advisory Fees Paid
Portfolio Turnover Rate
$2,747,110
25
$-
14%
Holdings [Text Block]

Country WeightingsFootnote Reference*

Group By Sector Chart
Table Summary
Value
Value
United Kingdom
2.9%
Portugal
3.2%
Mexico
3.8%
Australia
4.0%
Italy
6.4%
China
7.7%
Canada
8.2%
Spain
9.1%
France
12.1%
United States
34.6%
FootnoteDescription
Footnote*
Percentages are calculated based on total net assets.
Largest Holdings [Text Block]

Top Ten Holdings

Table Summary
Holding Name
Percentage of Total Net Assets
American Tower REIT
5.7%
Cellnex Telecom SA
5.2%
Prologis Inc REIT
4.5%
Union Pacific Corp
4.5%
CSX Corp
4.3%
Canadian National Railway Co
4.2%
Veolia Environnement SA
4.2%
NiSource Inc
4.1%
Eiffage SA
4.0%
Aurizon Holdings Ltd
4.0%
Updated Prospectus Phone Number 888-832-4386
Updated Prospectus Web Address https://www.mondrian.com/mutualfunds/global-listed-infrastructure-fund/
C000220240  
Shareholder Report [Line Items]  
Fund Name Mondrian Global Equity Value Fund
Class Name Institutional Shares
Trading Symbol MPGVX
Annual or Semi-Annual Statement [Text Block] Semi-Annual Shareholder Report
Shareholder Report Annual or Semi-Annual semi-annual shareholder report
Additional Information [Text Block] This semi-annual shareholder report contains important information about Institutional Shares of the Mondrian Global Equity Value Fund (the "Fund") for the period from November 1, 2025 to April 30, 2026. You can find additional information about the Fund at https://www.mondrian.com/mutualfunds/global-equity-value-fund/. You can also request this information by contacting us at 888-832-4386.
Additional Information Phone Number 888-832-4386
Additional Information Website https://www.mondrian.com/mutualfunds/global-equity-value-fund/
Expenses [Text Block]

What were the Fund costs for the last six months?

(based on a hypothetical $10,000 investment) 

Table Summary
Fund Name
Costs of a $10,000 investment
Costs paid as a percentage of a $10,000 investment
Mondrian Global Equity Value Fund, Institutional Shares
$38
0.74%
Expenses Paid, Amount $ 38
Expense Ratio, Percent 0.74%
AssetsNet $ 380,584,602
Holdings Count | Holding 54
Advisory Fees Paid, Amount $ 1,088,655
InvestmentCompanyPortfolioTurnover 20.00%
Additional Fund Statistics [Text Block]

Key Fund Statistics as of April 30, 2026

Table Summary
Total Net Assets
Number of Holdings
Total Advisory Fees Paid
Portfolio Turnover Rate
$380,584,602
54
$1,088,655
20%
Holdings [Text Block]

Country WeightingsFootnote Reference*

Group By Sector Chart
Table Summary
Value
Value
Other Countries
8.8%
Taiwan
1.8%
Italy
2.0%
Switzerland
2.0%
Finland
2.2%
Singapore
2.2%
China
3.3%
South Korea
3.5%
Germany
4.6%
Japan
5.3%
United Kingdom
7.3%
France
9.4%
United States
46.7%
FootnoteDescription
Footnote*
Percentages are calculated based on total net assets.
Largest Holdings [Text Block]

Top Ten Holdings

Table Summary
Holding Name
Percentage of Total Net Assets
Alphabet Inc, Cl A
3.6%
Samsung Electronics Co Ltd, Preference
3.5%
Microsoft Corp
3.1%
Texas Instruments Inc
2.9%
Merck & Co Inc
2.8%
Thermo Fisher Scientific Inc
2.8%
Lloyds Banking Group PLC
2.7%
London Stock Exchange Group PLC
2.5%
Charles Schwab Corp
2.5%
Deutsche Post AG
2.4%
Updated Prospectus Phone Number 888-832-4386
Updated Prospectus Web Address https://www.mondrian.com/mutualfunds/global-equity-value-fund/