CREDIT QUALITY ASSESSMENT (Activity in Allowance for Loan and Lease Losses by Respective Loan Portfolio Segment) (Detail) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended		12 Months Ended
	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015	Dec. 31, 2015
Financing Receivable Allowance For Credit Losses [Line Items]
Balance at beginning of year			$ 40,895	$ 37,802	$ 37,802
Provision (credit)	$ 2,957	$ 1,218	4,193	1,815	5,371
Charge-offs			(2,272)	(1,837)	(3,795)
Recoveries			568	933	1,517
Net charge-offs			(1,704)	(904)	(2,278)
Balance at period end	43,384	$ 38,713	43,384	38,713	40,895
Total loans and leases	$ 3,672,624		$ 3,672,624		$ 3,495,370
Allowance for loans and leases to total loans and leases ratio	1.18%		1.18%		1.17%
Balance of loans specifically evaluated for impairment	$ 25,120		$ 25,120		$ 28,927
Allowance for loans specifically evaluated for impairment	$ 3,778		$ 3,778		$ 3,375
Specific allowance to specific loans ratio	15.04%		15.04%		11.67%
Balance of loans collectively evaluated	$ 3,647,504		$ 3,647,504		$ 3,466,443
Allowance for loans collectively evaluated	39,606		$ 39,606		$ 37,520
Collective allowance to collective loans ratio			1.09%		1.08%
Commercial
Financing Receivable Allowance For Credit Losses [Line Items]
Balance at beginning of year			$ 6,529	5,852	$ 5,852
Provision (credit)			767		508
Charge-offs			(185)		(306)
Recoveries			12		475
Net charge-offs			(173)		169
Balance at period end	7,123		7,123		6,529
Total loans and leases	$ 451,711		$ 451,711		$ 465,765
Allowance for loans and leases to total loans and leases ratio	1.58%		1.58%		1.40%
Balance of loans specifically evaluated for impairment	$ 5,517		$ 5,517		$ 5,273
Allowance for loans specifically evaluated for impairment	$ 1,951		$ 1,951		$ 1,318
Specific allowance to specific loans ratio	35.36%		35.36%		25.00%
Balance of loans collectively evaluated	$ 446,194		$ 446,194		$ 460,492
Allowance for loans collectively evaluated	5,172		$ 5,172		$ 5,211
Collective allowance to collective loans ratio			1.16%		1.13%
Leases
Financing Receivable Allowance For Credit Losses [Line Items]
Balance at beginning of year			$ 0	9	$ 9
Provision (credit)			0		(5)
Charge-offs			0		(4)
Recoveries			0		0
Net charge-offs			0		(4)
Balance at period end	0		0		0
Total loans and leases	0		0		0
Consumer
Financing Receivable Allowance For Credit Losses [Line Items]
Balance at beginning of year			3,456	3,592	3,592
Provision (credit)			(145)		619
Charge-offs			(508)		(998)
Recoveries			90		243
Net charge-offs			(418)		(755)
Balance at period end	2,893		2,893		3,456
Total loans and leases	$ 447,149		$ 447,149		$ 450,875
Allowance for loans and leases to total loans and leases ratio	0.65%		0.65%		0.77%
Balance of loans collectively evaluated	$ 447,149		$ 447,149		$ 450,875
Allowance for loans collectively evaluated	2,893		$ 2,893		$ 3,456
Collective allowance to collective loans ratio			0.65%		0.77%
Commercial Real Estate Portfolio Segment | Commercial Acquisition, Development and Construction
Financing Receivable Allowance For Credit Losses [Line Items]
Balance at beginning of year			$ 4,691	4,267	$ 4,267
Provision (credit)			354		583
Charge-offs			(48)		(739)
Recoveries			0		580
Net charge-offs			(48)		(159)
Balance at period end	4,997		4,997		4,691
Total loans and leases	$ 285,585		$ 285,585		$ 255,980
Allowance for loans and leases to total loans and leases ratio	1.75%		1.75%		1.83%
Balance of loans specifically evaluated for impairment	$ 137		$ 137		$ 194
Allowance for loans specifically evaluated for impairment	$ 0		$ 0		$ 58
Specific allowance to specific loans ratio	0.00%		0.00%		29.90%
Balance of loans collectively evaluated	$ 285,448		$ 285,448		$ 255,786
Allowance for loans collectively evaluated	4,997		$ 4,997		$ 4,633
Collective allowance to collective loans ratio			1.75%		1.81%
Commercial Real Estate Portfolio Segment | Commercial Investor Real Estate
Financing Receivable Allowance For Credit Losses [Line Items]
Balance at beginning of year			$ 10,440	9,784	$ 9,784
Provision (credit)			1,478		727
Charge-offs			(197)		(91)
Recoveries			112		20
Net charge-offs			(85)		(71)
Balance at period end	11,833		11,833		10,440
Total loans and leases	$ 824,252		$ 824,252		$ 719,084
Allowance for loans and leases to total loans and leases ratio	1.44%		1.44%		1.45%
Balance of loans specifically evaluated for impairment	$ 9,720		$ 9,720		$ 10,441
Allowance for loans specifically evaluated for impairment	$ 1,274		$ 1,274		$ 1,489
Specific allowance to specific loans ratio	13.11%		13.11%		14.26%
Balance of loans collectively evaluated	$ 814,532		$ 814,532		$ 708,643
Allowance for loans collectively evaluated	10,559		$ 10,559		$ 8,951
Collective allowance to collective loans ratio			1.30%		1.26%
Commercial Real Estate Portfolio Segment | Commercial Owner Occupied Real Estate
Financing Receivable Allowance For Credit Losses [Line Items]
Balance at beginning of year			$ 7,984	7,143	$ 7,143
Provision (credit)			91		1,881
Charge-offs			0		(1,043)
Recoveries			4		3
Net charge-offs			4		(1,040)
Balance at period end	8,079		8,079		7,984
Total loans and leases	$ 700,599		$ 700,599		$ 678,027
Allowance for loans and leases to total loans and leases ratio	1.15%		1.15%		1.18%
Balance of loans specifically evaluated for impairment	$ 6,424		$ 6,424		$ 6,580
Allowance for loans specifically evaluated for impairment	$ 553		$ 553		$ 510
Specific allowance to specific loans ratio	8.61%		8.61%		7.75%
Balance of loans collectively evaluated	$ 694,175		$ 694,175		$ 671,447
Allowance for loans collectively evaluated	7,526		$ 7,526		$ 7,474
Collective allowance to collective loans ratio			1.08%		1.11%
Residential Real Estate Portfolio Segment | Residential Mortgage
Financing Receivable Allowance For Credit Losses [Line Items]
Balance at beginning of year			$ 6,901	6,232	$ 6,232
Provision (credit)			1,660		1,138
Charge-offs			(1,334)		(614)
Recoveries			330		145
Net charge-offs			(1,004)		(469)
Balance at period end	7,557		7,557		6,901
Total loans and leases	$ 820,618		$ 820,618		$ 796,358
Allowance for loans and leases to total loans and leases ratio	0.92%		0.92%		0.87%
Balance of loans specifically evaluated for impairment	$ 3,322		$ 3,322		$ 6,439
Allowance for loans specifically evaluated for impairment	0		0		0
Balance of loans collectively evaluated	817,296		817,296		789,919
Allowance for loans collectively evaluated	7,557		$ 7,557		$ 6,901
Collective allowance to collective loans ratio			0.92%		0.87%
Residential Real Estate Portfolio Segment | Residential Construction
Financing Receivable Allowance For Credit Losses [Line Items]
Balance at beginning of year			$ 894	$ 923	$ 923
Provision (credit)			(12)		(80)
Charge-offs			0		0
Recoveries			20		51
Net charge-offs			20		51
Balance at period end	902		902		894
Total loans and leases	$ 142,710		$ 142,710		$ 129,281
Allowance for loans and leases to total loans and leases ratio	0.63%		0.63%		0.69%
Balance of loans specifically evaluated for impairment	$ 0		$ 0		$ 0
Allowance for loans specifically evaluated for impairment	0		0		0
Balance of loans collectively evaluated	142,710		142,710		129,281
Allowance for loans collectively evaluated	$ 902		$ 902		$ 894
Collective allowance to collective loans ratio			0.63%		0.69%