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, 2019	Dec. 31, 2018
Financing Receivable Impaired [Line Items]
Impaired loans with a specific allowance	$ 17,848	$ 12,876
Allowance	5,341	4,924
Impaired loans without a specific allowance	8,292	9,334
Impaired loans	26,140	22,210
Unpaid principal balance in total impaired loans	38,737	35,121
Non Accrual Loans
Financing Receivable Impaired [Line Items]
Impaired loans with a specific allowance	14,034	10,010
Impaired loans without a specific allowance	3,129	4,844
Impaired loans	17,163	14,854
Restructuring | Accrual Loans
Financing Receivable Impaired [Line Items]
Impaired loans with a specific allowance	105	328
Impaired loans without a specific allowance	2,374	1,614
Impaired loans	2,479	1,942
Restructuring | Non Accrual Loans
Financing Receivable Impaired [Line Items]
Impaired loans with a specific allowance	3,709	2,538
Impaired loans without a specific allowance	2,789	2,876
Impaired loans	6,498	5,414
Commercial
Financing Receivable Impaired [Line Items]
Impaired loans with a specific allowance	6,962	6,220
Allowance	3,624	3,594
Impaired loans without a specific allowance	1,324	1,366
Impaired loans	8,286	7,586
Unpaid principal balance in total impaired loans	11,421	11,056
Commercial | Non Accrual Loans
Financing Receivable Impaired [Line Items]
Impaired loans with a specific allowance	4,706	4,126
Impaired loans without a specific allowance	214	220
Impaired loans	4,920	4,346
Commercial | Restructuring | Accrual Loans
Financing Receivable Impaired [Line Items]
Impaired loans with a specific allowance	105	328
Impaired loans without a specific allowance	168	172
Impaired loans	273	500
Commercial | Restructuring | Non Accrual Loans
Financing Receivable Impaired [Line Items]
Impaired loans with a specific allowance	2,151	1,766
Impaired loans without a specific allowance	942	974
Impaired loans	3,093	2,740
All Other
Financing Receivable Impaired [Line Items]
Impaired loans with a specific allowance	0	0
Allowance	0	0
Impaired loans without a specific allowance	1,711	1,729
Impaired loans	1,711	1,729
Unpaid principal balance in total impaired loans	3,066	3,081
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	1,432	1,442
Impaired loans	1,432	1,442
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	279	287
Impaired loans	279	287
Commercial Real Estate Portfolio Segment | Commercial Acquisition, Development and Construction
Financing Receivable Impaired [Line Items]
Impaired loans with a specific allowance	1,261	0
Allowance	151	0
Impaired loans without a specific allowance	2,045	3,306
Impaired loans	3,306	3,306
Unpaid principal balance in total impaired loans	4,419	4,419
Commercial Real Estate Portfolio Segment | Commercial Acquisition, Development and Construction | Non Accrual Loans
Financing Receivable Impaired [Line Items]
Impaired loans with a specific allowance	1,261	0
Impaired loans without a specific allowance	1,910	3,170
Impaired loans	3,171	3,170
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	135	136
Impaired loans	135	136
Commercial Real Estate Portfolio Segment | Commercial Investor Real Estate
Financing Receivable Impaired [Line Items]
Impaired loans with a specific allowance	5,906	5,117
Allowance	1,315	1,207
Impaired loans without a specific allowance	939	238
Impaired loans	6,845	5,355
Unpaid principal balance in total impaired loans	11,397	9,909
Commercial Real Estate Portfolio Segment | Commercial Investor Real Estate | Non Accrual Loans
Financing Receivable Impaired [Line Items]
Impaired loans with a specific allowance	5,117	5,117
Impaired loans without a specific allowance	165	238
Impaired loans	5,282	5,355
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	774	0
Impaired loans	774	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	789	0
Impaired loans without a specific allowance	0	0
Impaired loans	789	0
Commercial Real Estate Portfolio Segment | Commercial Owner Occupied Real Estate
Financing Receivable Impaired [Line Items]
Impaired loans with a specific allowance	3,719	1,539
Allowance	251	123
Impaired loans without a specific allowance	2,273	2,695
Impaired loans	5,992	4,234
Unpaid principal balance in total impaired loans	8,434	6,656
Commercial Real Estate Portfolio Segment | Commercial Owner Occupied Real Estate | Non Accrual Loans
Financing Receivable Impaired [Line Items]
Impaired loans with a specific allowance	2,950	767
Impaired loans without a specific allowance	840	1,216
Impaired loans	3,790	1,983
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	0
Impaired loans	0	0
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	769	772
Impaired loans without a specific allowance	1,433	1,479
Impaired loans	$ 2,202	$ 2,251