LOANS AND LEASES - Commercial and Consumer Credit Exposure by Risk Attribute (Details) - USD ($) $ in Thousands	Jun. 30, 2017	Dec. 31, 2016
Financing Receivable, Recorded Investment [Line Items]
Commercial	$ 1,824,589	$ 1,781,948
Real Estate - Construction	443,112	399,434
Real Estate - Commercial	2,471,655	2,427,577
Lease financing	88,152	93,108
Total Commercial	4,827,508	4,702,067
Pass
Financing Receivable, Recorded Investment [Line Items]
Commercial	1,767,573	1,725,451
Real Estate - Construction	442,021	398,155
Real Estate - Commercial	2,414,945	2,349,662
Lease financing	87,875	92,540
Total Commercial	4,712,414	4,565,808
Special Mention
Financing Receivable, Recorded Investment [Line Items]
Commercial	27,225	18,256
Real Estate - Construction	0	1,258
Real Estate - Commercial	11,096	15,584
Lease financing	65	108
Total Commercial	38,386	35,206
Substandard
Financing Receivable, Recorded Investment [Line Items]
Commercial	29,791	38,241
Real Estate - Construction	1,091	21
Real Estate - Commercial	45,614	62,331
Lease financing	212	460
Total Commercial	76,708	101,053
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	490,398	500,980
Residential real estate \| Performing
Financing Receivable, Recorded Investment [Line Items]
Loans and Leases Receivable, before Fees, Gross	481,770	491,380
Residential real estate \| Nonperforming
Financing Receivable, Recorded Investment [Line Items]
Loans and Leases Receivable, before Fees, Gross	8,628	9,600
Home equity
Financing Receivable, Recorded Investment [Line Items]
Loans and Leases Receivable, before Fees, Gross	464,066	460,388
Home equity \| Performing
Financing Receivable, Recorded Investment [Line Items]
Loans and Leases Receivable, before Fees, Gross	460,362	456,314
Home equity \| Nonperforming
Financing Receivable, Recorded Investment [Line Items]
Loans and Leases Receivable, before Fees, Gross	3,704	4,074
Installment
Financing Receivable, Recorded Investment [Line Items]
Loans and Leases Receivable, before Fees, Gross	47,654	50,639
Installment \| Performing
Financing Receivable, Recorded Investment [Line Items]
Loans and Leases Receivable, before Fees, Gross	47,329	50,202
Installment \| Nonperforming
Financing Receivable, Recorded Investment [Line Items]
Loans and Leases Receivable, before Fees, Gross	325	437
Credit card
Financing Receivable, Recorded Investment [Line Items]
Loans and Leases Receivable, before Fees, Gross	44,139	43,408
Credit card \| Performing
Financing Receivable, Recorded Investment [Line Items]
Loans and Leases Receivable, before Fees, Gross	44,139	43,408
Credit card \| 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	1,046,257	1,055,415
Total consumer loans \| Performing
Financing Receivable, Recorded Investment [Line Items]
Loans and Leases Receivable, before Fees, Gross	1,033,600	1,041,304
Total consumer loans \| Nonperforming
Financing Receivable, Recorded Investment [Line Items]
Loans and Leases Receivable, before Fees, Gross	$ 12,657	$ 14,111

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 and fees, of loans and leases receivable. Excludes loans and 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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