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Nature of Operations and Summary of Significant Accounting Policies (Details) $ in Thousands	6 Months Ended
	Jun. 30, 2026 USD ($) facility	Dec. 31, 2025 USD ($)	Oct. 17, 2023 USD ($)
Nature of Operations and Summary of Significant Accounting Policies
Deferred stock issuance costs			$ 1,600
Number of facilities \| facility	2
Cash accounts in excess of federally insured limits	$ 500	$ 504
Accrued interest receivable on available-for-sale debt securities	334	346
Accrued interest receivable on held-to-maturity debt securities	$ 16	23
Forecast period	2 years
Accrued interest on loans	$ 374	$ 388
PFS Bancorp \| Public Shareholders
Nature of Operations and Summary of Significant Accounting Policies
Ownership percentage			100.00%
Peru Federal Savings Bank
Nature of Operations and Summary of Significant Accounting Policies
Ownership percentage			100.00%
Buildings and improvements \| Minimum
Nature of Operations and Summary of Significant Accounting Policies
Premises and equipment useful lives	5 years
Buildings and improvements \| Maximum
Nature of Operations and Summary of Significant Accounting Policies
Premises and equipment useful lives	50 years
Equipment \| Minimum
Nature of Operations and Summary of Significant Accounting Policies
Premises and equipment useful lives	3 years
Equipment \| Maximum
Nature of Operations and Summary of Significant Accounting Policies
Premises and equipment useful lives	7 years