CREDIT QUALITY ASSESSMENT (Credit Quality of Loan Portfolio) (Detail) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Financing Receivable Recorded Investment Past Due [Line Items]
Total past due		$ 27,748
Non-accrual loans	$ 51,374	38,632
Loans aquired with deteriorated credit quality		13,084
Current loans		6,625,768
Total loans	6,722,992	6,705,232
Commercial [Member]
Financing Receivable Recorded Investment Past Due [Line Items]
Total past due		1,278
Non-accrual loans	10,834	8,450
Loans aquired with deteriorated credit quality		2,539
Current loans		788,752
Total loans	813,525	801,019
Consumer
Financing Receivable Recorded Investment Past Due [Line Items]
Loans aquired with deteriorated credit quality		993
Current loans		457,450
Total loans	453,346	466,764
Commercial Real Estate Portfolio Segment \| Commercial AD&C [Member]
Financing Receivable Recorded Investment Past Due [Line Items]
Total past due		0
Non-accrual loans	829	829
Loans aquired with deteriorated credit quality		0
Current loans		683,181
Total loans	643,114	684,010
Commercial Real Estate Portfolio Segment \| Commercial Investor RE [Member]
Financing Receivable Recorded Investment Past Due [Line Items]
Total past due		932
Non-accrual loans	17,770	8,437
Loans aquired with deteriorated credit quality		9,544
Current loans		2,150,243
Total loans	2,241,240	2,169,156
Commercial Real Estate Portfolio Segment \| Commercial Owner Occupied RE [Member]
Financing Receivable Recorded Investment Past Due [Line Items]
Total past due		316
Non-accrual loans	4,074	4,148
Loans aquired with deteriorated credit quality		0
Current loans		1,284,213
Total loans	1,305,682	1,288,677
Residential Real Estate Portfolio Segment \| Residential Mortgage
Financing Receivable Recorded Investment Past Due [Line Items]
Total past due		19,394
Non-accrual loans	12,271	12,661
Loans aquired with deteriorated credit quality		8
Current loans		1,117,264
Total loans	1,116,512	1,149,327
Residential Real Estate Portfolio Segment \| Residential Construction
Financing Receivable Recorded Investment Past Due [Line Items]
Total past due		1,614
Non-accrual loans	0	0
Loans aquired with deteriorated credit quality		0
Current loans		144,665
Total loans	149,573	146,279
31-60 days
Financing Receivable Recorded Investment Past Due [Line Items]
Total past due	48,253	19,986
31-60 days \| Commercial [Member]
Financing Receivable Recorded Investment Past Due [Line Items]
Total past due	2,671	908
31-60 days \| Commercial Real Estate Portfolio Segment \| Commercial AD&C [Member]
Financing Receivable Recorded Investment Past Due [Line Items]
Total past due	9,356	0
31-60 days \| Commercial Real Estate Portfolio Segment \| Commercial Investor RE [Member]
Financing Receivable Recorded Investment Past Due [Line Items]
Total past due	13,521	932
31-60 days \| Commercial Real Estate Portfolio Segment \| Commercial Owner Occupied RE [Member]
Financing Receivable Recorded Investment Past Due [Line Items]
Total past due	3,255	316
31-60 days \| Residential Real Estate Portfolio Segment \| Residential Mortgage
Financing Receivable Recorded Investment Past Due [Line Items]
Total past due	16,324	14,853
31-60 days \| Residential Real Estate Portfolio Segment \| Residential Construction
Financing Receivable Recorded Investment Past Due [Line Items]
Total past due	0	280
61-90 days
Financing Receivable Recorded Investment Past Due [Line Items]
Total past due	8,546	7,762
61-90 days \| Commercial [Member]
Financing Receivable Recorded Investment Past Due [Line Items]
Total past due	438	370
61-90 days \| Commercial Real Estate Portfolio Segment \| Commercial AD&C [Member]
Financing Receivable Recorded Investment Past Due [Line Items]
Total past due	0	0
61-90 days \| Commercial Real Estate Portfolio Segment \| Commercial Investor RE [Member]
Financing Receivable Recorded Investment Past Due [Line Items]
Total past due	1,011	0
61-90 days \| Commercial Real Estate Portfolio Segment \| Commercial Owner Occupied RE [Member]
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	4,322	4,541
61-90 days \| Residential Real Estate Portfolio Segment \| Residential Construction
Financing Receivable Recorded Investment Past Due [Line Items]
Total past due	$ 1,471	1,334
> 90 days
Financing Receivable Recorded Investment Past Due [Line Items]
Total past due		0
> 90 days \| Commercial [Member]
Financing Receivable Recorded Investment Past Due [Line Items]
Total past due		0
> 90 days \| Commercial Real Estate Portfolio Segment \| Commercial AD&C [Member]
Financing Receivable Recorded Investment Past Due [Line Items]
Total past due		0
> 90 days \| Commercial Real Estate Portfolio Segment \| Commercial Investor RE [Member]
Financing Receivable Recorded Investment Past Due [Line Items]
Total past due		0
> 90 days \| Commercial Real Estate Portfolio Segment \| Commercial Owner Occupied RE [Member]
Financing Receivable Recorded Investment Past Due [Line Items]
Total past due		0
> 90 days \| Residential Real Estate Portfolio Segment \| Residential Mortgage
Financing Receivable Recorded Investment Past Due [Line Items]
Total past due		0
> 90 days \| Residential Real Estate Portfolio Segment \| Residential Construction
Financing Receivable Recorded Investment Past Due [Line Items]
Total past due		$ 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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