v3.26.1
Shareholder Report, Line Graph (Details) 193137_Themes Transatlantic Defense ETF_TF_TSR Annual {TF} - USD ($)
12 Months Ended
Oct. 10, 2024
Sep. 30, 2025
Sep. 30, 2025
Themes Transatlantic Defense ETF      
Account Value [Line Items]      
Line Graph and Table Measure Name     Themes Transatlantic Defense ETF NAV
Accumulated Value $ 10,000   $ 15,570
MSCI ACWI Net Total Return Index (USD)      
Account Value [Line Items]      
Line Graph and Table Measure Name   MSCI ACWI Net Total Return Index (USD)  
Accumulated Value 10,000 $ 11,773  
Solactive Transatlantic Aerospace and Defense Index NTR      
Account Value [Line Items]      
Line Graph and Table Measure Name   Solactive Transatlantic Aerospace and Defense Index NTR  
Accumulated Value $ 10,000 $ 15,619