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	Mar. 31, 2018	Dec. 31, 2017
Financing Receivable Impaired [Line Items]
Impaired loans with a specific allowance	$ 11,446	$ 11,693
Impaired loans without a specific allowance	9,347	9,116
Impaired loans	20,793	20,809
Impaired Financing Receivable, Related Allowance	4,479	4,014
Unpaid principal balance in total impaired loans	32,618	32,689
Accrual Loans
Financing Receivable Impaired [Line Items]
Impaired loans with a specific allowance	0
Impaired loans	0
Non Accrual Loans
Financing Receivable Impaired [Line Items]
Impaired loans with a specific allowance	9,692	9,673
Impaired loans without a specific allowance	2,264	2,127
Impaired loans	11,956	11,800
Restructuring | Accrual Loans
Financing Receivable Impaired [Line Items]
Impaired loans with a specific allowance	863	1,129
Impaired loans without a specific allowance	1,815	1,659
Impaired loans	2,678	2,788
Restructuring | Non Accrual Loans
Financing Receivable Impaired [Line Items]
Impaired loans with a specific allowance	891	891
Impaired loans without a specific allowance	5,268	5,330
Impaired loans	6,159	6,221
Commercial
Financing Receivable Impaired [Line Items]
Impaired loans with a specific allowance	5,508	5,753
Impaired loans without a specific allowance	2,436	2,352
Impaired loans	7,944	8,105
Impaired Financing Receivable, Related Allowance	3,096	3,220
Unpaid principal balance in total impaired loans	11,003	11,263
Commercial | Accrual Loans
Financing Receivable Impaired [Line Items]
Impaired loans with a specific allowance	0
Impaired loans	0
Commercial | Non Accrual Loans
Financing Receivable Impaired [Line Items]
Impaired loans with a specific allowance	4,534	4,516
Impaired loans without a specific allowance	317	391
Impaired loans	4,851	4,907
Commercial | Restructuring | Accrual Loans
Financing Receivable Impaired [Line Items]
Impaired loans with a specific allowance	863	1,129
Impaired loans without a specific allowance	447	273
Impaired loans	1,310	1,402
Commercial | Restructuring | Non Accrual Loans
Financing Receivable Impaired [Line Items]
Impaired loans with a specific allowance	111	108
Impaired loans without a specific allowance	1,672	1,688
Impaired loans	1,783	1,796
All Other
Financing Receivable Impaired [Line Items]
Impaired loans with a specific allowance	0	0
Impaired loans without a specific allowance	2,891	2,915
Impaired loans	2,891	2,915
Impaired Financing Receivable, Related Allowance	0	0
Unpaid principal balance in total impaired loans	3,667	3,681
All Other | Accrual Loans
Financing Receivable Impaired [Line Items]
Impaired loans with a specific allowance	0
Impaired loans	0
All Other | 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
All Other | Restructuring | Accrual Loans
Financing Receivable Impaired [Line Items]
Impaired loans with a specific allowance	0	0
Impaired loans without a specific allowance	883	890
Impaired loans	883	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	2,008	2,025
Impaired loans	2,008	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 | Accrual Loans
Financing Receivable Impaired [Line Items]
Impaired loans with a specific allowance	0
Impaired loans	0
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	5,158	5,157
Impaired loans without a specific allowance	655	418
Impaired loans	5,813	5,575
Impaired Financing Receivable, Related Allowance	1,255	663
Unpaid principal balance in total impaired loans	10,401	10,166
Commercial Real Estate Portfolio Segment | Commercial Investor Real Estate | Accrual Loans
Financing Receivable Impaired [Line Items]
Impaired loans with a specific allowance	0
Impaired loans	0
Commercial Real Estate Portfolio Segment | Commercial Investor Real Estate | Non Accrual Loans
Financing Receivable Impaired [Line Items]
Impaired loans with a specific allowance	5,158	5,157
Impaired loans without a specific allowance	655	418
Impaired loans	5,813	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	780	783
Impaired loans without a specific allowance	3,229	3,295
Impaired loans	4,009	4,078
Impaired Financing Receivable, Related Allowance	128	131
Unpaid principal balance in total impaired loans	6,299	6,331
Commercial Real Estate Portfolio Segment | Commercial Owner Occupied Real Estate | Accrual Loans
Financing Receivable Impaired [Line Items]
Impaired loans with a specific allowance	0
Impaired loans	0
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	1,292	1,318
Impaired loans	1,292	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	485	496
Impaired loans	485	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	780	783
Impaired loans without a specific allowance	1,452	1,481
Impaired loans	$ 2,232	$ 2,264