v3.25.4
Summary of Significant Accounting Policies - Additional Information (Details) - USD ($)
Apr. 30, 2025
Dec. 31, 2025
Jun. 30, 2025
Dec. 31, 2024
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]        
Sale of common stock shares 3,997,012      
Price per share $ 10      
Common stock proceeds $ 39,970,000      
Number of common stock company sold   9,295,376 9,295,376  
Common stock, shares outstanding   9,295,376 9,295,376 0
Winchester Bancorp, MHC        
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]        
Number of common stock company sold 5,112,457      
Winchester savings bank charitable foundation, inc.        
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]        
Number of common stock company sold 185,907