CREDIT QUALITY ASSESSMENT (Credit Quality of Loan Portfolio) (Detail) - USD ($) $ in Thousands	Sep. 30, 2019	Dec. 31, 2018
Financing Receivable Recorded Investment Past Due [Line Items]
Total past due	$ 33,166	$ 27,235
Non-accrual loans	36,621	33,583
Loans aquired with deteriorated credit quality	13,285	25,947
Current loans	6,513,476	6,484,869
Total loans	6,596,548	6,571,634
Commercial
Financing Receivable Recorded Investment Past Due [Line Items]
Total past due	2,362	2,786
Non-accrual loans	6,393	7,086
Loans aquired with deteriorated credit quality	2,590	8,155
Current loans	761,274	778,237
Total loans	772,619	796,264
Consumer
Financing Receivable Recorded Investment Past Due [Line Items]
Total past due	3,019	5,567
Non-accrual loans	4,561	4,107
Loans aquired with deteriorated credit quality	1,028	1,272
Current loans	471,922	506,893
Total loans	480,530	517,839
Commercial Real Estate Portfolio Segment \| Commercial Acquisition, Development and Construction
Financing Receivable Recorded Investment Past Due [Line Items]
Total past due	2,828	474
Non-accrual loans	829	3,306
Loans aquired with deteriorated credit quality	0	0
Current loans	675,249	677,421
Total loans	678,906	681,201
Commercial Real Estate Portfolio Segment \| Commercial Investor Real Estate
Financing Receivable Recorded Investment Past Due [Line Items]
Total past due	4,289	3,830
Non-accrual loans	8,454	5,355
Loans aquired with deteriorated credit quality	9,658	14,328
Current loans	2,013,620	1,934,882
Total loans	2,036,021	1,958,395
Commercial Real Estate Portfolio Segment \| Commercial Owner Occupied Real Estate
Financing Receivable Recorded Investment Past Due [Line Items]
Total past due	3,407	433
Non-accrual loans	3,810	4,234
Loans aquired with deteriorated credit quality	0	2,182
Current loans	1,271,288	1,196,054
Total loans	1,278,505	1,202,903
Residential Real Estate Portfolio Segment \| Residential Mortgage
Financing Receivable Recorded Investment Past Due [Line Items]
Total past due	14,831	10,919
Non-accrual loans	12,574	9,336
Loans aquired with deteriorated credit quality	9	10
Current loans	1,171,861	1,207,982
Total loans	1,199,275	1,228,247
Residential Real Estate Portfolio Segment \| Residential Construction
Financing Receivable Recorded Investment Past Due [Line Items]
Total past due	2,430	3,226
Non-accrual loans	0	159
Loans aquired with deteriorated credit quality	0	0
Current loans	148,262	183,400
Total loans	150,692	186,785
31-60 days
Financing Receivable Recorded Investment Past Due [Line Items]
Total past due	23,565	21,963
31-60 days \| Commercial
Financing Receivable Recorded Investment Past Due [Line Items]
Total past due	1,429	2,737
31-60 days \| Consumer
Financing Receivable Recorded Investment Past Due [Line Items]
Total past due	1,834	3,871
31-60 days \| Commercial Real Estate Portfolio Segment \| Commercial Acquisition, Development and Construction
Financing Receivable Recorded Investment Past Due [Line Items]
Total past due	2,828	474
31-60 days \| Commercial Real Estate Portfolio Segment \| Commercial Investor Real Estate
Financing Receivable Recorded Investment Past Due [Line Items]
Total past due	885	3,041
31-60 days \| Commercial Real Estate Portfolio Segment \| Commercial Owner Occupied Real Estate
Financing Receivable Recorded Investment Past Due [Line Items]
Total past due	3,407	433
31-60 days \| Residential Real Estate Portfolio Segment \| Residential Mortgage
Financing Receivable Recorded Investment Past Due [Line Items]
Total past due	11,229	8,181
31-60 days \| Residential Real Estate Portfolio Segment \| Residential Construction
Financing Receivable Recorded Investment Past Due [Line Items]
Total past due	1,953	3,226
61-90 days
Financing Receivable Recorded Investment Past Due [Line Items]
Total past due	8,383	4,783
61-90 days \| Commercial
Financing Receivable Recorded Investment Past Due [Line Items]
Total past due	916	0
61-90 days \| Consumer
Financing Receivable Recorded Investment Past Due [Line Items]
Total past due	1,185	1,477
61-90 days \| Commercial Real Estate Portfolio Segment \| Commercial Acquisition, Development and Construction
Financing Receivable Recorded Investment Past Due [Line Items]
Total past due	0	0
61-90 days \| Commercial Real Estate Portfolio Segment \| Commercial Investor Real Estate
Financing Receivable Recorded Investment Past Due [Line Items]
Total past due	2,203	789
61-90 days \| Commercial Real Estate Portfolio Segment \| Commercial Owner Occupied Real Estate
Financing Receivable Recorded Investment Past Due [Line Items]
Total past due	0	0
61-90 days \| Residential Real Estate Portfolio Segment \| Residential Mortgage
Financing Receivable Recorded Investment Past Due [Line Items]
Total past due	3,602	2,517
61-90 days \| Residential Real Estate Portfolio Segment \| Residential Construction
Financing Receivable Recorded Investment Past Due [Line Items]
Total past due	477	0
> 90 days
Financing Receivable Recorded Investment Past Due [Line Items]
Total past due	1,218	489
> 90 days \| Commercial
Financing Receivable Recorded Investment Past Due [Line Items]
Total past due	17	49
> 90 days \| Consumer
Financing Receivable Recorded Investment Past Due [Line Items]
Total past due	0	219
> 90 days \| Commercial Real Estate Portfolio Segment \| Commercial Acquisition, Development and Construction
Financing Receivable Recorded Investment Past Due [Line Items]
Total past due	0	0
> 90 days \| Commercial Real Estate Portfolio Segment \| Commercial Investor Real Estate
Financing Receivable Recorded Investment Past Due [Line Items]
Total past due	1,201	0
> 90 days \| Commercial Real Estate Portfolio Segment \| Commercial Owner Occupied Real Estate
Financing Receivable Recorded Investment Past Due [Line Items]
Total past due	0	0
> 90 days \| Residential Real Estate Portfolio Segment \| Residential Mortgage
Financing Receivable Recorded Investment Past Due [Line Items]
Total past due	0	221
> 90 days \| Residential Real Estate Portfolio Segment \| Residential Construction
Financing Receivable Recorded Investment Past Due [Line Items]
Total past due	$ 0	$ 0

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Amount before allowance and after deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Excludes loans and leases covered under loss sharing agreements.

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