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Number of retired employees receiving retirement benefits.

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SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Additional Information (Details)	1 Months Ended	2 Months Ended	3 Months Ended	12 Months Ended
	Jan. 31, 2024 item	Feb. 27, 2026 $ / shares	Mar. 31, 2024 USD ($)	Dec. 31, 2025 USD ($) category item employee $ / shares shares	Dec. 31, 2024 USD ($) $ / shares shares
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES
Number of Reportable Segments \| item	1			1
Number of loan portfolio segments \| category				2
Tax credits on investments in low income housing partnerships				$ 840,000
Amortization of investment in low-income housing partnerships				$ 819,000	$ 819,000
Number of retired employees \| employee				2
Goodwill impairment			$ 19,133,000	$ 0	19,133,000
Goodwill				0	0
Assets held for resale				$ 0	0
Loan payments delinquency period beyond which loans considered past due				10 days
Delinquency notice is automatically generated				10 or 15 days
Loan payments delinquency period, non accrual				90 days
Assets held-in-trust				$ 122,111,000	120,857,000
Loans held for sale				1,140,000	737,000
Unpaid principal balance				946,661,000	946,826,000
Reserve for unfunded lending commitments				90,000	102,000
Accrued interest exclude from the amortized cost basis of loans				$ 2,736,000	$ 2,575,000
Cash dividends, per share \| $ / shares				$ 1.12	$ 1.12
Allowance for credit losses for Available-For-Sale debt securities				$ 0	$ 0
Accrued interest receivable on debt securities available-for-sale				$ 2,068,000	$ 2,142,000
Debt Securities, Available-for-Sale, Accrued Interest, after Allowance for Credit Loss, Statement of Financial Position [Extensible Enumeration]				Interest Receivable	Interest Receivable
Impairment loss on investment in equity securities				$ 0	$ 0
Number of common stock shares outstanding potential \| shares				0	0
Subsequent Event \| 2026 Q1 Dividends
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES
Cash dividends, per share \| $ / shares		$ 0.28
Dividends payable, declared date		Feb. 27, 2026
Dividends Payable, record date		Mar. 12, 2026
Dividends payable, to be paid date		Mar. 31, 2026
Mortgage Loan Service
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES
Amount of loans serviced for others				$ 75,372,000	$ 77,262,000
Mortgage servicing rights				196,000	218,000
Fees and commissions				190,000	200,000
Amortization of mortgage servicing rights (MSRs)				64,000	72,000
Unfunded Loan Commitment
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES
Reserve for unfunded lending commitments				$ 90,000	102,000
Real estate \| Maximum
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES
Term of loan offering				20 years
Maximum loan to value ratio				80.00%
Residential Real Estate
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES
Loans held for sale				$ 1,140,000	737,000
Residential Real Estate \| Maximum
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES
Maximum loan to value ratio				80.00%
Maximum loan to value ratio with PMI				95.00%
Residential Real Estate \| Maximum \| Held for Investment
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES
Term of loan offering				20 years
Residential Real Estate \| Maximum \| Residential Mortgage
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES
Term of loan offering				30 years
Residential Real Estate \| Maximum \| Home Equity Loan
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES
Term of loan offering				15 years
Maximum loan to value ratio				80.00%
Residential Real Estate \| Maximum \| Home Equity Line of Credit
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES
Term of loan offering				20 years
Maximum loan to value ratio				80.00%
Agricultural
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES
Unpaid principal balance				$ 984,000	936,000
Agricultural \| Maximum
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES
Term of loan offering				10 years
Maximum loan to value ratio				70.00%
Bank Owned Life Insurance
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES
Deferred compensation arrangement with individual recorded liability				$ 63,000	63,000
Deferred Compensation Arrangement with Individual, Compensation Expense				0	1,000
Federal Home Loan Bank of Pittsburgh
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES
Restricted Investment in Bank Stocks				8,909,000	8,949,000
Atlantic Central Bankers Bank
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES
Restricted Investment in Bank Stocks				$ 35,000	35,000
Full Service Offices
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES
Number of Stores				19
Automated Teller Machine
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES
Number of Stores				20
GGLs
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES
Unpaid principal balance				$ 3,902,000	$ 4,306,000
Originated For Resale \| Residential Real Estate \| Maximum \| Residential Mortgage
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES
Term of loan offering				30 years