v3.26.1
Document And Entity Information
12 Months Ended
Dec. 31, 2025
Document Information Line Items  
Entity Central Index Key 0001070524
Document Type 11-K
Document Period End Date Dec. 31, 2025
Document Fiscal Year Focus 2025
Entity Registrant Name Greene County Bancorp, Inc.
Amendment Flag false
The Bank of Greene County Employees’ Savings and Profit Sharing Plan and Trust [Member]  
Document Information Line Items  
Document Type 11-K
Document Period End Date Dec. 31, 2025
Document Fiscal Year Focus 2025
Amendment Flag false