LOANS AND LEASES - Additional Information (Details)	3 Months Ended		9 Months Ended
	Sep. 30, 2019 USD ($)	Sep. 30, 2018 USD ($) loans	Sep. 30, 2019 USD ($) loans	Sep. 30, 2018 USD ($) loans	Jun. 30, 2019 USD ($)	Dec. 31, 2018 USD ($)	Jun. 30, 2018 USD ($)	Dec. 31, 2017 USD ($)
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Troubled Debt Restructuring, Subsequent Default	$ 100,000	$ 0	$ 7,000,000.0
Financing Receivable, Troubled Debt Restructuring, Subsequent Default, Number of Contracts	1	0	3	1
Financing Recivable Modifications, Investment Recorded				$ 41,000
Restructured Loans, Portion Determined to be Uncollectible	$ 2,316,000	$ 700,000	$ 2,300,000	800,000
Purchased impaired loans	76,443,000		76,443,000			$ 96,320,000
Restructured Loans, Nonaccrual Status	21,500,000		21,500,000			22,400,000
Write-downs	(424,000)	455,000	310,000	717,000
Real Estate Acquired Through Foreclosure	1,613,000	1,918,000	1,613,000	1,918,000	$ 1,421,000	$ 1,401,000	$ 1,853,000	$ 2,781,000
Commercial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Restructured Loans, Loan Relationships, Review Threshold Amount Minimum			250,000
Residential real estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Restructured Loans, Loan Relationships, Review Threshold Amount Minimum			250,000
Write-downs	$ (480,000)	$ 197,000	$ 199,000	$ 362,000