LOANS - Commercial and Consumer Credit Exposure by Risk Attribute (Detail) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Financing Receivable, Recorded Investment [Line Items]
Commercial and industrial	$ 1,781,948	$ 1,663,102
Real Estate - Construction	399,434	311,712
Real Estate - Commercial	2,427,577	2,258,297
Lease financing	93,108	93,986
Total Commercial	4,702,067	4,327,097
Pass
Financing Receivable, Recorded Investment [Line Items]
Commercial and industrial	1,725,451	1,596,415
Real Estate - Construction	398,155	310,806
Real Estate - Commercial	2,349,662	2,179,701
Lease financing	92,540	93,236
Total Commercial	4,565,808	4,180,158
Special Mention
Financing Receivable, Recorded Investment [Line Items]
Commercial and industrial	18,256	27,498
Real Estate - Construction	1,258	128
Real Estate - Commercial	15,584	19,903
Lease financing	108	0
Total Commercial	35,206	47,529
Substandard
Financing Receivable, Recorded Investment [Line Items]
Commercial and industrial	38,241	39,189
Real Estate - Construction	21	778
Real Estate - Commercial	62,331	58,693
Lease financing	460	750
Total Commercial	101,053	99,410
Doubtful
Financing Receivable, Recorded Investment [Line Items]
Commercial and industrial	0	0
Real Estate - Construction	0	0
Real Estate - Commercial	0	0
Lease financing	0	0
Total Commercial	0	0
Residential Real Estate [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans and Leases Receivable before Fees, Gross	500,980	512,311
Residential Real Estate [Member] \| Performing
Financing Receivable, Recorded Investment [Line Items]
Loans and Leases Receivable before Fees, Gross	491,380	503,317
Residential Real Estate [Member] \| Nonperforming
Financing Receivable, Recorded Investment [Line Items]
Loans and Leases Receivable before Fees, Gross	9,600	8,994
Home Equity Loan [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans and Leases Receivable before Fees, Gross	460,388	466,629
Home Equity Loan [Member] \| Performing
Financing Receivable, Recorded Investment [Line Items]
Loans and Leases Receivable before Fees, Gross	456,314	461,188
Home Equity Loan [Member] \| Nonperforming
Financing Receivable, Recorded Investment [Line Items]
Loans and Leases Receivable before Fees, Gross	4,074	5,441
Consumer Loan [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans and Leases Receivable before Fees, Gross	50,639	41,506
Consumer Loan [Member] \| Performing
Financing Receivable, Recorded Investment [Line Items]
Loans and Leases Receivable before Fees, Gross	50,202	41,253
Consumer Loan [Member] \| Nonperforming
Financing Receivable, Recorded Investment [Line Items]
Loans and Leases Receivable before Fees, Gross	437	253
Credit card
Financing Receivable, Recorded Investment [Line Items]
Loans and Leases Receivable before Fees, Gross	43,408	41,217
Credit card \| Performing
Financing Receivable, Recorded Investment [Line Items]
Loans and Leases Receivable before Fees, Gross	43,408	41,217
Credit card \| Nonperforming
Financing Receivable, Recorded Investment [Line Items]
Loans and Leases Receivable before Fees, Gross	0	0
Installment
Financing Receivable, Recorded Investment [Line Items]
Loans and Leases Receivable before Fees, Gross	1,055,415	1,061,663
Installment \| Performing
Financing Receivable, Recorded Investment [Line Items]
Loans and Leases Receivable before Fees, Gross	1,041,304	1,046,975
Installment \| Nonperforming
Financing Receivable, Recorded Investment [Line Items]
Loans and Leases Receivable before Fees, Gross	$ 14,111	$ 14,688

Loans and Leases Receivable, Gross, Total of Commercial, Consumer Real Estate/Construction and Commercial Mortgage

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Amount before allowance of commercial leases and leveraged lease transactions where the entity is long-term creditor. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. Excludes leases covered under loss sharing agreements.

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Amount before allowance of loans issued to commercial and industrial institutions. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. Excludes real estate loans and loans covered under loss sharing agreements.

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Amount before allowance of commercial construction loans. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. Excludes loans covered under loss sharing agreements.

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Amount before allowance of mortgage loans on existing land or building. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. Excludes loans covered under loss sharing agreements.

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