Loans - Summary of Amortized Cost Basis Of Loans (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2025	Jun. 30, 2024	Jun. 30, 2025	Jun. 30, 2024
Financing Receivable, Impaired [Line Items]
Modified Term Extension	$ 2,369	$ 0	$ 4,385	$ 0
Total Class of Receivable	0.60%	0.00%	1.10%	0.00%
Interest Rate Reduction	$ 11,495	$ 0	$ 11,495	$ 0
Total Class of Receivable	3.00%	0.00%	3.00%	0.00%
Home Equity and Consumer [Member]
Financing Receivable, Impaired [Line Items]
Modified Term Extension	$ 0	$ 0	$ 0	$ 0
Total Class of Receivable	0.00%	0.00%	0.00%	0.00%
Interest Rate Reduction	$ 0	$ 0	$ 0	$ 0
Total Class of Receivable	0.00%	0.00%	0.00%	0.00%
Residential Mortgage Loans [Member]
Financing Receivable, Impaired [Line Items]
Modified Term Extension	$ 0	$ 0	$ 0	$ 0
Total Class of Receivable	0.00%	0.00%	0.00%	0.00%
Interest Rate Reduction	$ 0	$ 0	$ 0	$ 0
Total Class of Receivable	0.00%	0.00%	0.00%	0.00%
Commercial Loans [Member] \| Real Estate [Member]
Financing Receivable, Impaired [Line Items]
Modified Term Extension	$ 0	$ 0	$ 2,017	$ 0
Total Class of Receivable	0.00%	0.00%	0.50%	0.00%
Interest Rate Reduction	$ 11,495	$ 0	$ 11,495	$ 0
Total Class of Receivable	3.00%	0.00%	3.00%	0.00%
Commercial Loans [Member] \| Lines of Credit [Member]
Financing Receivable, Impaired [Line Items]
Modified Term Extension	$ 0	$ 0	$ 0	$ 0
Total Class of Receivable	0.00%	0.00%	0.00%	0.00%
Interest Rate Reduction	$ 0	$ 0	$ 0	$ 0
Total Class of Receivable	0.00%	0.00%	0.00%	0.00%
Commercial Loans [Member] \| Other Commercial and Industrial [Member]
Financing Receivable, Impaired [Line Items]
Modified Term Extension	$ 2,369	$ 0	$ 2,369	$ 0
Total Class of Receivable	0.60%	0.00%	0.60%	0.00%
Interest Rate Reduction	$ 0	$ 0	$ 0	$ 0
Total Class of Receivable	0.00%	0.00%	0.00%	0.00%

Pathfinder Bancorp, Inc. 10-Q