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SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Additional Information (Details)	3 Months Ended					12 Months Ended
	Dec. 31, 2021 USD ($) loan item shares	Jun. 30, 2021 USD ($) loan	Dec. 31, 2020 USD ($) loan shares	Mar. 31, 2020	Mar. 31, 2008 USD ($)	Dec. 31, 2021 USD ($) employee loan item shares	Dec. 31, 2020 USD ($) loan shares	Feb. 23, 2022 $ / shares	Sep. 30, 2021 USD ($) loan	Mar. 31, 2021 USD ($) loan
Tax Credits On Investments In Low Income Housing Partnerships						$ 405,000	$ 405,000
Amortization Of Investments In Limited Partnerships						$ 371,000	362,000
Number of retired employees \| employee						2
Goodwill impairment							0
Loan Payments Delinquency Period Beyond Which Loans Considered Past Due						10 days
Loan Payments Delinquency Period Beyond Which Loans Considered Non Accrual						90 days
Assets Held-in-trust	$ 108,339,000		$ 107,336,000			$ 108,339,000	107,336,000
Maximum loan to value ratio with PMI	95.00%					95.00%
Loans Receivable Held-for-sale, Amount	$ 6,006,000		17,300,000			$ 6,006,000	17,300,000
Purchase of investment in real estate venture						$ (435,000)	0
Interest rate						1.00%
Operating Lease, Right-of-Use Asset	1,025,000		1,061,000			$ 1,025,000	1,061,000
Operating Lease, Liability	$ 1,499,000		$ 1,513,000			$ 1,499,000	$ 1,513,000
Loan Payments, Delinquency Period, at which time Delinquency Notice is Automatically Generated						10 or 15 days
Increase (decrease) in qualitative factors by basis points	1.00%	1.00%	2.00%	2.00%
Number of common stock shares outstanding potential \| shares	0		0			0	0
Mortgage Loan Service [Member]
Loans Serviced For Others	$ 93,906,000		$ 86,981,000			$ 93,906,000	$ 86,981,000
Servicing Asset at Fair Value, Amount	$ 367,000		$ 262,000			367,000	262,000
Fees and Commissions, Mortgage Banking and Servicing						228,000	231,000
Amortization of Mortgage Servicing Rights (MSRs)						$ 120,000	$ 130,000
Subsequent Event
Dividends Payable, Amount Per Share \| $ / shares								$ 0.28
Commercial and Industrial [Member] \| First Round of Paycheck Protection Program Loans Issuance
Number of loans funded \| loan	2		441			2	441
Loan Funded Under Paycheck Protection Program	$ 160,000		$ 22,976,000			$ 160,000	$ 22,976,000
Commercial and Industrial [Member] \| Second Round of Paycheck Protection Program Loans Issuance
Number of loans funded \| loan	120					120
Loan Funded Under Paycheck Protection Program	$ 4,734,000					$ 4,734,000
Unfunded Loan Commitment [Member]
Reserve For Unfunded Lending Commitments	177,000		129,000			$ 177,000	129,000
Minimum
Term of loan						2 years
Maximum
Term of loan						5 years
Commercial Real Estate Loans [Member]
Increase (decrease) in qualitative factors by basis points		1.00%
Commercial Real Estate Loans [Member] \| Maximum
Term of Loan Offering						20 years
Maximum Loan to Value Ratio						80.00%
Residential Real Estate
Increase (decrease) in qualitative factors by basis points		1.00%
Residential Real Estate \| Maximum \| Held for Investment [Member]
Term of Loan Offering						20 years
Residential Real Estate \| Maximum \| Residential Mortgage [Member]
Maximum Loan to Value Ratio						80.00%
Residential Real Estate \| Maximum \| Home Equity Loan [Member]
Maximum Loan to Value Ratio						80.00%
Residential Real Estate \| Maximum \| Home Equity Line of Credit [Member]
Term of Loan Offering						20 years
Maximum Loan to Value Ratio						80.00%
Bank Owned Life Insurance [Member]
Deferred Compensation Arrangement with Individual, Recorded Liability	56,000		36,000			$ 56,000	36,000
Deferred Compensation Arrangement with Individual, Compensation Expense						(20,000)	2,000
Pocono Community Bank [Member]
Goodwill, Purchase Accounting Adjustments					$ 152,000
Federal Home Loan Bank of Pittsburgh [Member]
Restricted Investment in Bank Stocks	1,884,000		2,212,000			1,884,000	2,212,000
Atlantic Central Bankers Bank [Member]
Restricted Investment in Bank Stocks	$ 35,000		35,000			$ 35,000	35,000
Full Service Offices [Member]
Number of Stores	18					18
Loan Production Office [Member]
Number of Stores \| item	1					1
Automated Teller [Member]
Number of Stores	20					20
Government Guaranteed Loans
Government Guaranteed Loans.	$ 3,829,000		$ 5,128,000			$ 3,829,000	$ 5,128,000
Paycheck Protection Program Loans \| Commercial and Industrial [Member]
Number of loans funded \| loan	122					122
Loan Funded Under Paycheck Protection Program	$ 4,894,000					$ 4,894,000
CARES Act Section 4013 Program For Loan Modifications [Member]
Count	1	8	44			1	44		1	17
Investment	$ 9,423,000	$ 10,568,000	$ 16,541,000			$ 9,423,000	$ 16,541,000		$ 9,423,000	$ 13,641,000
CARES Act Section 4013 Program For Loan Modifications [Member] \| Residential Real Estate
Count \| loan			2				2			1
Investment			$ 269,000				$ 269,000			$ 155,000
Originated For Resale [Member] \| Residential Real Estate \| Residential Mortgage [Member]
Loans held for sale term	30 years					30 years
Originated For Resale [Member] \| Residential Real Estate \| Maximum \| Residential Mortgage [Member]
Term of Loan Offering						30 years
Home Equity Term Loans [Member] \| Residential Real Estate \| Maximum
Term of Loan Offering						15 years