LOANS AND LEASES - Additional Information (Details) - USD ($)	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018	Dec. 31, 2018	Dec. 31, 2017
Accounts, Notes, Loans and Financing Receivable [Line Items]
Restructured Loans, Portion Determined to be Uncollectible	$ 0	$ 0
Purchased impaired loans	88,343,000		$ 96,320,000
Restructured Loans, Nonaccrual Status	13,100,000		22,400,000
Write-downs	57,000	123,000
Real Estate Acquired Through Foreclosure	1,665,000	1,065,000	$ 1,401,000	$ 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	$ 57,000	$ 26,000