CREDIT QUALITY ASSESSMENT (Credit Risk Rating Indicators for Each Segment of Commercial Loan Portfolio) (Detail) - USD ($) $ in Thousands	Mar. 31, 2016	Dec. 31, 2015
Financing Receivable Recorded Investment [Line Items]
Total loans and leases	$ 3,560,688	$ 3,495,370
Commercial
Financing Receivable Recorded Investment [Line Items]
Total loans and leases	451,239	465,765
Pass | Commercial
Financing Receivable Recorded Investment [Line Items]
Total loans and leases	427,917	447,439
Special Mention | Commercial
Financing Receivable Recorded Investment [Line Items]
Total loans and leases	5,189	797
Substandard | Commercial
Financing Receivable Recorded Investment [Line Items]
Total loans and leases	18,133	17,529
Doubtful | Commercial
Financing Receivable Recorded Investment [Line Items]
Total loans and leases	0	0
Commercial Portfolio Segment [Member]
Financing Receivable Recorded Investment [Line Items]
Total loans and leases	2,171,164	2,118,856
Commercial Portfolio Segment [Member] | Pass
Financing Receivable Recorded Investment [Line Items]
Total loans and leases	2,117,238	2,069,129
Commercial Portfolio Segment [Member] | Special Mention
Financing Receivable Recorded Investment [Line Items]
Total loans and leases	8,399	5,662
Commercial Portfolio Segment [Member] | Substandard
Financing Receivable Recorded Investment [Line Items]
Total loans and leases	45,527	44,065
Commercial Portfolio Segment [Member] | Doubtful
Financing Receivable Recorded Investment [Line Items]
Total loans and leases	0	0
Commercial Real Estate Portfolio Segment | Commercial Acquisition, Development and Construction
Financing Receivable Recorded Investment [Line Items]
Total loans and leases	261,204	255,980
Commercial Real Estate Portfolio Segment | Commercial Investor Real Estate
Financing Receivable Recorded Investment [Line Items]
Total loans and leases	783,161	719,084
Commercial Real Estate Portfolio Segment | Commercial Owner Occupied Real Estate
Financing Receivable Recorded Investment [Line Items]
Total loans and leases	675,560	678,027
Commercial Real Estate Portfolio Segment | Pass | Commercial Acquisition, Development and Construction
Financing Receivable Recorded Investment [Line Items]
Total loans and leases	261,057	255,786
Commercial Real Estate Portfolio Segment | Pass | Commercial Investor Real Estate
Financing Receivable Recorded Investment [Line Items]
Total loans and leases	771,226	706,623
Commercial Real Estate Portfolio Segment | Pass | Commercial Owner Occupied Real Estate
Financing Receivable Recorded Investment [Line Items]
Total loans and leases	657,038	659,281
Commercial Real Estate Portfolio Segment | Special Mention | Commercial Acquisition, Development and Construction
Financing Receivable Recorded Investment [Line Items]
Total loans and leases	0	0
Commercial Real Estate Portfolio Segment | Special Mention | Commercial Investor Real Estate
Financing Receivable Recorded Investment [Line Items]
Total loans and leases	892	1,509
Commercial Real Estate Portfolio Segment | Special Mention | Commercial Owner Occupied Real Estate
Financing Receivable Recorded Investment [Line Items]
Total loans and leases	2,318	3,356
Commercial Real Estate Portfolio Segment | Substandard | Commercial Acquisition, Development and Construction
Financing Receivable Recorded Investment [Line Items]
Total loans and leases	147	194
Commercial Real Estate Portfolio Segment | Substandard | Commercial Investor Real Estate
Financing Receivable Recorded Investment [Line Items]
Total loans and leases	11,043	10,952
Commercial Real Estate Portfolio Segment | Substandard | Commercial Owner Occupied Real Estate
Financing Receivable Recorded Investment [Line Items]
Total loans and leases	16,204	15,390
Commercial Real Estate Portfolio Segment | Doubtful | Commercial Acquisition, Development and Construction
Financing Receivable Recorded Investment [Line Items]
Total loans and leases	0	0
Commercial Real Estate Portfolio Segment | Doubtful | Commercial Investor Real Estate
Financing Receivable Recorded Investment [Line Items]
Total loans and leases	0	0
Commercial Real Estate Portfolio Segment | Doubtful | Commercial Owner Occupied Real Estate
Financing Receivable Recorded Investment [Line Items]
Total loans and leases	$ 0	$ 0