SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Additional information (Details) - USD ($)	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Summary Of Significant Accounting Policies [Line Items]
Trading account securities on hand	$ 0	$ 0
Equity securities	0	0
Other-than-temporary impairment	$ 0	0	$ 0
Useful life of intangible assets	10 years
Advertising expense	$ 333,000	648,000	382,000
Payments to Acquire Limited Partnership Interests	4,400,000
Other real estate owned	$ 5,802,000	7,299,000
Building [Member] | Minimum [Member]
Summary Of Significant Accounting Policies [Line Items]
Property, Plant and Equipment, Useful Life	10 years
Building [Member] | Maximum [Member]
Summary Of Significant Accounting Policies [Line Items]
Property, Plant and Equipment, Useful Life	39 years
Furniture and Fixtures [Member] | Minimum [Member]
Summary Of Significant Accounting Policies [Line Items]
Property, Plant and Equipment, Useful Life	3 years
Furniture and Fixtures [Member] | Maximum [Member]
Summary Of Significant Accounting Policies [Line Items]
Property, Plant and Equipment, Useful Life	10 years
Limited Partner [Member]
Summary Of Significant Accounting Policies [Line Items]
Real Estate Investments	$ 2,500,000	3,000,000.0
Affordable Housing Tax Credits And Other Tax Benefits	$ 481,000	$ 481,000	$ 481,000