LOANS AND LEASES - Commercial and Consumer Credit Exposure by Risk Attribute (Details) - USD ($) $ in Thousands	Jun. 30, 2016	Dec. 31, 2015
Financing Receivable, Recorded Investment [Line Items]
Commercial	$ 1,794,533	$ 1,663,102
Real Estate - Construction	374,949	311,712
Real Estate - Commercial	2,363,456	2,258,297
Lease financing	100,263	93,986
Total Commercial	4,633,201	4,327,097
Pass
Financing Receivable, Recorded Investment [Line Items]
Commercial	1,715,798	1,596,415
Real Estate - Construction	368,565	310,806
Real Estate - Commercial	2,269,024	2,179,701
Lease financing	97,603	93,236
Total Commercial	4,450,990	4,180,158
Special Mention
Financing Receivable, Recorded Investment [Line Items]
Commercial	31,872	27,498
Real Estate - Construction	5,761	128
Real Estate - Commercial	29,629	19,903
Lease financing	149	0
Total Commercial	67,411	47,529
Substandard
Financing Receivable, Recorded Investment [Line Items]
Commercial	46,863	39,189
Real Estate - Construction	623	778
Real Estate - Commercial	64,803	58,693
Lease financing	2,511	750
Total Commercial	114,800	99,410
Doubtful
Financing Receivable, Recorded Investment [Line Items]
Commercial	0	0
Real Estate - Construction	0	0
Real Estate - Commercial	0	0
Lease financing	0	0
Total Commercial	0	0
Residential real estate
Financing Receivable, Recorded Investment [Line Items]
Loans and Leases Receivable before Fees, Gross	512,800	512,311
Residential real estate \| Performing
Financing Receivable, Recorded Investment [Line Items]
Loans and Leases Receivable before Fees, Gross	503,713	503,317
Residential real estate \| Nonperforming
Financing Receivable, Recorded Investment [Line Items]
Loans and Leases Receivable before Fees, Gross	9,087	8,994
Home equity
Financing Receivable, Recorded Investment [Line Items]
Loans and Leases Receivable before Fees, Gross	467,549	466,629
Home equity \| Performing
Financing Receivable, Recorded Investment [Line Items]
Loans and Leases Receivable before Fees, Gross	462,665	461,188
Home equity \| Nonperforming
Financing Receivable, Recorded Investment [Line Items]
Loans and Leases Receivable before Fees, Gross	4,884	5,441
Installment
Financing Receivable, Recorded Investment [Line Items]
Loans and Leases Receivable before Fees, Gross	46,917	41,506
Installment \| Performing
Financing Receivable, Recorded Investment [Line Items]
Loans and Leases Receivable before Fees, Gross	46,381	41,253
Installment \| Nonperforming
Financing Receivable, Recorded Investment [Line Items]
Loans and Leases Receivable before Fees, Gross	536	253
Other
Financing Receivable, Recorded Investment [Line Items]
Loans and Leases Receivable before Fees, Gross	40,746	41,217
Other \| Performing
Financing Receivable, Recorded Investment [Line Items]
Loans and Leases Receivable before Fees, Gross	40,746	41,217
Other \| Nonperforming
Financing Receivable, Recorded Investment [Line Items]
Loans and Leases Receivable before Fees, Gross	0	0
Total consumer loans
Financing Receivable, Recorded Investment [Line Items]
Loans and Leases Receivable before Fees, Gross	1,068,012	1,061,663
Total consumer loans \| Performing
Financing Receivable, Recorded Investment [Line Items]
Loans and Leases Receivable before Fees, Gross	1,053,505	1,046,975
Total consumer loans \| Nonperforming
Financing Receivable, Recorded Investment [Line Items]
Loans and Leases Receivable before Fees, Gross	$ 14,507	$ 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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