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, 2017	Dec. 31, 2016
Financing Receivable Impaired [Line Items]
Impaired loans with a specific allowance	$ 13,436	$ 13,563
Impaired loans without a specific allowance	9,077	10,529
Impaired loans	22,513	24,092
Impaired Financing Receivable, Related Allowance	4,770	4,825
Unpaid principal balance in total impaired loans	37,308	39,016
Accrual Loans
Financing Receivable Impaired [Line Items]
Impaired loans with a specific allowance	896
Impaired loans	896
Non Accrual Loans
Financing Receivable Impaired [Line Items]
Impaired loans with a specific allowance	10,755	11,720
Impaired loans without a specific allowance	2,597	3,207
Impaired loans	13,352	14,927
Restructuring | Accrual Loans
Financing Receivable Impaired [Line Items]
Impaired loans with a specific allowance	1,138	1,140
Impaired loans without a specific allowance	1,333	1,349
Impaired loans	2,471	2,489
Restructuring | Non Accrual Loans
Financing Receivable Impaired [Line Items]
Impaired loans with a specific allowance	647	703
Impaired loans without a specific allowance	5,147	5,973
Impaired loans	5,794	6,676
Commercial
Financing Receivable Impaired [Line Items]
Impaired loans with a specific allowance	6,397	4,011
Impaired loans without a specific allowance	2,006	3,007
Impaired loans	8,403	7,018
Impaired Financing Receivable, Related Allowance	3,841	2,604
Unpaid principal balance in total impaired loans	11,331	10,082
Commercial | Accrual Loans
Financing Receivable Impaired [Line Items]
Impaired loans with a specific allowance	896
Impaired loans	896
Commercial | Non Accrual Loans
Financing Receivable Impaired [Line Items]
Impaired loans with a specific allowance	4,355	2,807
Impaired loans without a specific allowance	556	1,562
Impaired loans	4,911	4,369
Commercial | Restructuring | Accrual Loans
Financing Receivable Impaired [Line Items]
Impaired loans with a specific allowance	1,138	1,140
Impaired loans without a specific allowance	278	45
Impaired loans	1,416	1,185
Commercial | Restructuring | Non Accrual Loans
Financing Receivable Impaired [Line Items]
Impaired loans with a specific allowance	8	64
Impaired loans without a specific allowance	1,172	1,400
Impaired loans	1,180	1,464
All Other
Financing Receivable Impaired [Line Items]
Impaired loans with a specific allowance	0	0
Impaired loans without a specific allowance	2,867	3,263
Impaired loans	2,867	3,263
Impaired Financing Receivable, Related Allowance	0	0
Unpaid principal balance in total impaired loans	3,699	3,971
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	550	560
Impaired loans	550	560
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	2,317	2,703
Impaired loans	2,317	2,703
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	137	137
Impaired loans	137	137
Impaired Financing Receivable, Related Allowance	0	0
Unpaid principal balance in total impaired loans	4,398	4,398
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	137	137
Impaired loans	137	137
Commercial Real Estate Portfolio Segment | Commercial Investor Real Estate
Financing Receivable Impaired [Line Items]
Impaired loans with a specific allowance	5,177	7,029
Impaired loans without a specific allowance	412	1,078
Impaired loans	5,589	8,107
Impaired Financing Receivable, Related Allowance	589	1,736
Unpaid principal balance in total impaired loans	10,173	12,805
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	5,177	7,029
Impaired loans without a specific allowance	412	562
Impaired loans	5,589	7,591
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	516
Impaired loans	0	516
Commercial Real Estate Portfolio Segment | Commercial Owner Occupied Real Estate
Financing Receivable Impaired [Line Items]
Impaired loans with a specific allowance	1,862	2,523
Impaired loans without a specific allowance	3,655	3,044
Impaired loans	5,517	5,567
Impaired Financing Receivable, Related Allowance	340	485
Unpaid principal balance in total impaired loans	7,707	7,760
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	1,223	1,884
Impaired loans without a specific allowance	1,629	1,083
Impaired loans	2,852	2,967
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	505	744
Impaired loans	505	744
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	639	639
Impaired loans without a specific allowance	1,521	1,217
Impaired loans	$ 2,160	$ 1,856