ALLOWANCE FOR LOAN LOSSES AND CREDIT QUALITY INFORMATION - Schedule of Loans Identified as Troubled Debt Restructurings During Periods Indicated (Detail) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Financing Receivable, Modifications [Line Items]
Total loans identified during the period	$ 1,640	$ 6,052
Commercial
Financing Receivable, Modifications [Line Items]
Total loans identified during the period	0	443
Commercial mortgages
Financing Receivable, Modifications [Line Items]
Total loans identified during the period	458	0
Construction
Financing Receivable, Modifications [Line Items]
Total loans identified during the period	920	1,712
Residential
Financing Receivable, Modifications [Line Items]
Total loans identified during the period	0	242
Consumer
Financing Receivable, Modifications [Line Items]
Total loans identified during the period	262	584
Owner-occupied commercial
Financing Receivable, Modifications [Line Items]
Total loans identified during the period	$ 0	$ 3,071