CREDIT QUALITY ASSESSMENT (Recorded Investment with Respect to Impaired loans, Associated Allowance by Applicable Portfolio Segment and Principal Balance of Impaired Loans prior to Amounts Charged-off) (Detail) - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017
Financing Receivable Impaired [Line Items]
Impaired loans with a specific allowance	$ 11,450	$ 11,693
Impaired loans without a specific allowance	6,898	9,116
Impaired loans	18,348	20,809
Impaired Financing Receivable, Related Allowance	4,204	4,014
Unpaid principal balance in total impaired loans	30,326	32,689
Non Accrual Loans
Financing Receivable Impaired [Line Items]
Impaired loans with a specific allowance	8,418	9,673
Impaired loans without a specific allowance	1,933	2,127
Impaired loans	10,351	11,800
Restructuring | Accrual Loans
Financing Receivable Impaired [Line Items]
Impaired loans with a specific allowance	335	1,129
Impaired loans without a specific allowance	1,889	1,659
Impaired loans	2,224	2,788
Restructuring | Non Accrual Loans
Financing Receivable Impaired [Line Items]
Impaired loans with a specific allowance	2,697	891
Impaired loans without a specific allowance	3,076	5,330
Impaired loans	5,773	6,221
Commercial
Financing Receivable Impaired [Line Items]
Impaired loans with a specific allowance	5,518	5,753
Impaired loans without a specific allowance	1,605	2,352
Impaired loans	7,123	8,105
Impaired Financing Receivable, Related Allowance	2,827	3,220
Unpaid principal balance in total impaired loans	10,255	11,263
Commercial | Non Accrual Loans
Financing Receivable Impaired [Line Items]
Impaired loans with a specific allowance	3,261	4,516
Impaired loans without a specific allowance	175	391
Impaired loans	3,436	4,907
Commercial | Restructuring | Accrual Loans
Financing Receivable Impaired [Line Items]
Impaired loans with a specific allowance	335	1,129
Impaired loans without a specific allowance	436	273
Impaired loans	771	1,402
Commercial | Restructuring | Non Accrual Loans
Financing Receivable Impaired [Line Items]
Impaired loans with a specific allowance	1,922	108
Impaired loans without a specific allowance	994	1,688
Impaired loans	2,916	1,796
All Other
Financing Receivable Impaired [Line Items]
Impaired loans with a specific allowance	0	0
Impaired loans without a specific allowance	1,876	2,915
Impaired loans	1,876	2,915
Impaired Financing Receivable, Related Allowance	0	0
Unpaid principal balance in total impaired loans	2,633	3,681
All Other | Non Accrual Loans
Financing Receivable Impaired [Line Items]
Impaired loans without a specific allowance	0	0
Impaired loans	0	0
All Other | Restructuring | Accrual Loans
Financing Receivable Impaired [Line Items]
Impaired loans with a specific allowance	0	0
Impaired loans without a specific allowance	1,453	890
Impaired loans	1,453	890
All Other | Restructuring | Non Accrual Loans
Financing Receivable Impaired [Line Items]
Impaired loans with a specific allowance	0	0
Impaired loans without a specific allowance	423	2,025
Impaired loans	423	2,025
Commercial Real Estate Portfolio Segment | Commercial Acquisition, Development and Construction
Financing Receivable Impaired [Line Items]
Impaired loans with a specific allowance	0	0
Impaired loans without a specific allowance	136	136
Impaired loans	136	136
Impaired Financing Receivable, Related Allowance	0	0
Unpaid principal balance in total impaired loans	1,248	1,248
Commercial Real Estate Portfolio Segment | Commercial Acquisition, Development and Construction | Non Accrual Loans
Financing Receivable Impaired [Line Items]
Impaired loans with a specific allowance	0	0
Impaired loans without a specific allowance	0	0
Impaired loans	0	0
Commercial Real Estate Portfolio Segment | Commercial Acquisition, Development and Construction | Restructuring | Accrual Loans
Financing Receivable Impaired [Line Items]
Impaired loans with a specific allowance	0	0
Impaired loans without a specific allowance	0	0
Impaired loans	0	0
Commercial Real Estate Portfolio Segment | Commercial Acquisition, Development and Construction | Restructuring | Non Accrual Loans
Financing Receivable Impaired [Line Items]
Impaired loans with a specific allowance	0	0
Impaired loans without a specific allowance	136	136
Impaired loans	136	136
Commercial Real Estate Portfolio Segment | Commercial Investor Real Estate
Financing Receivable Impaired [Line Items]
Impaired loans with a specific allowance	5,157	5,157
Impaired loans without a specific allowance	704	418
Impaired loans	5,861	5,575
Impaired Financing Receivable, Related Allowance	1,255	663
Unpaid principal balance in total impaired loans	10,467	10,166
Commercial Real Estate Portfolio Segment | Commercial Investor Real Estate | Non Accrual Loans
Financing Receivable Impaired [Line Items]
Impaired loans with a specific allowance	5,157	5,157
Impaired loans without a specific allowance	704	418
Impaired loans	5,861	5,575
Commercial Real Estate Portfolio Segment | Commercial Investor Real Estate | Restructuring | Accrual Loans
Financing Receivable Impaired [Line Items]
Impaired loans with a specific allowance	0	0
Impaired loans without a specific allowance	0	0
Impaired loans	0	0
Commercial Real Estate Portfolio Segment | Commercial Investor Real Estate | Restructuring | Non Accrual Loans
Financing Receivable Impaired [Line Items]
Impaired loans with a specific allowance	0	0
Impaired loans without a specific allowance	0	0
Impaired loans	0	0
Commercial Real Estate Portfolio Segment | Commercial Owner Occupied Real Estate
Financing Receivable Impaired [Line Items]
Impaired loans with a specific allowance	775	783
Impaired loans without a specific allowance	2,577	3,295
Impaired loans	3,352	4,078
Impaired Financing Receivable, Related Allowance	122	131
Unpaid principal balance in total impaired loans	5,723	6,331
Commercial Real Estate Portfolio Segment | Commercial Owner Occupied Real Estate | Non Accrual Loans
Financing Receivable Impaired [Line Items]
Impaired loans with a specific allowance	0	0
Impaired loans without a specific allowance	1,054	1,318
Impaired loans	1,054	1,318
Commercial Real Estate Portfolio Segment | Commercial Owner Occupied Real Estate | Restructuring | Accrual Loans
Financing Receivable Impaired [Line Items]
Impaired loans with a specific allowance	0	0
Impaired loans without a specific allowance	0	496
Impaired loans	0	496
Commercial Real Estate Portfolio Segment | Commercial Owner Occupied Real Estate | Restructuring | Non Accrual Loans
Financing Receivable Impaired [Line Items]
Impaired loans with a specific allowance	775	783
Impaired loans without a specific allowance	1,523	1,481
Impaired loans	$ 2,298	$ 2,264