OPERATIONS AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Premises and Equipment, Goodwill, Intangible Assets, and Investments in Limited Partnerships (Details)	12 Months Ended
	Dec. 31, 2021 USD ($) partnership business	Dec. 31, 2020 USD ($)	Dec. 31, 2019 USD ($)
Finite-Lived Intangible Assets [Line Items]
Goodwill impairment loss	$ 0	$ 0	$ 0
Subsidiary of Limited Liability Company or Limited Partnership [Line Items]
Number of partnerships held by entity | partnership	1
Investment in Low Income Housing Limited Partnerships	$ 4,607,000	3,944,000
Tax credit receipt period over which investment in the partnership entered into after 2004 are being fully amortized	10 years
Amortization of investment in low income housing limited partnerships	$ 407,000
Furniture, fixtures, and equipment | Minimum
Premises and equipment
Estimated useful lives (in years)	5 years
Furniture, fixtures, and equipment | Maximum
Premises and equipment
Estimated useful lives (in years)	10 years
Buildings and improvements | Minimum
Premises and equipment
Estimated useful lives (in years)	15 years
Buildings and improvements | Maximum
Premises and equipment
Estimated useful lives (in years)	40 years
Disposal Group, Disposed of by Means Other than Sale, Not Discontinued Operations
Subsidiary of Limited Liability Company or Limited Partnership [Line Items]
Investment in Low Income Housing Limited Partnerships			33,000
Amortization of investment in low income housing limited partnerships		$ 33,000	$ 184,000
Luzerne National Bank Corporation
Finite-Lived Intangible Assets [Line Items]
Intangible assets net	$ 67,000
Accumulated amortization	$ 1,947,000
Useful life (in years)	10 years
Acquisition of Businesses Related to Investment Product Sales
Finite-Lived Intangible Assets [Line Items]
Intangible assets net	$ 413,000
Accumulated amortization	$ 607,000
Useful life (in years)	10 years
Number of businesses acquired | business	2