v3.26.1
Segment and Related Information - Narrative (Details)
6 Months Ended 10 Months Ended
Jun. 30, 2026
banking_office
segment
Oct. 31, 2025
segment
Segment Reporting [Line Items]    
Number of reportable segments | segment 2  
Number of operating segments | segment   3
Ithaca, New York And Surrounding Communities    
Segment Reporting [Line Items]    
Number of banking offices 12  
Genesee Valley Region Of New York State    
Segment Reporting [Line Items]    
Number of banking offices 14  
Counties North Of New York City    
Segment Reporting [Line Items]    
Number of banking offices 12  
Southeastern Pennsylvania    
Segment Reporting [Line Items]    
Number of banking offices 16