v3.26.1
Shareholder Report, Average Annual Return (Details) 194692_Themes US Small Cap Cash Flow Champions ETF_TF_TSR Annual {TF}
12 Months Ended 22 Months Ended
Sep. 30, 2025
Sep. 30, 2025
Themes US Small Cap Cash Flow Champions ETF    
Average Annual Return [Line Items]    
Line Graph and Table Measure Name Themes US Small Cap Cash Flow Champions ETF  
Average Annual Return, Percent 8.43% 17.71%
S&P 500 Index    
Average Annual Return [Line Items]    
Line Graph and Table Measure Name S&P 500 Index  
Average Annual Return, Percent 17.60% 24.09%
Solactive US Small Cap Cash Flow Champions Index    
Average Annual Return [Line Items]    
Line Graph and Table Measure Name Solactive US Small Cap Cash Flow Champions Index  
Average Annual Return, Percent 7.97% 17.67%