LOANS AND LEASES - Commercial and Consumer Credit Exposure by Risk Attribute (Details) - USD ($) $ in Thousands	Sep. 30, 2015	Dec. 31, 2014
Financing Receivable, Recorded Investment [Line Items]
Commercial	$ 1,637,467	$ 1,315,114
Real Estate - Construction	276,240	197,571
Real Estate - Commercial	2,169,662	2,140,667
Lease financing	82,679	77,567
Total Commercial	4,166,048	3,730,919
Real Estate Residential	506,653	501,894
Installment	39,974	47,320
Home equity	463,629	458,627
Other	39,759	38,475
Total	1,050,015	1,046,316
Pass
Financing Receivable, Recorded Investment [Line Items]
Commercial	1,571,656	1,265,116
Real Estate - Construction	275,197	195,787
Real Estate - Commercial	2,081,930	2,027,897
Lease financing	81,053	75,839
Total Commercial	4,009,836	3,564,639
Special Mention
Financing Receivable, Recorded Investment [Line Items]
Commercial	40,433	30,903
Real Estate - Construction	130	0
Real Estate - Commercial	20,414	25,928
Lease financing	1,626	1,728
Total Commercial	62,603	58,559
Substandard
Financing Receivable, Recorded Investment [Line Items]
Commercial	25,378	19,095
Real Estate - Construction	913	1,784
Real Estate - Commercial	67,318	86,842
Lease financing	0	0
Total Commercial	93,609	107,721
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
Performing
Financing Receivable, Recorded Investment [Line Items]
Real Estate Residential	497,643	490,314
Installment	39,547	46,806
Home equity	457,893	452,281
Other	39,759	38,475
Total	1,034,842	1,027,876
Nonperforming
Financing Receivable, Recorded Investment [Line Items]
Real Estate Residential	9,010	11,580
Installment	427	514
Home equity	5,736	6,346
Other	0	0
Total	$ 15,173	$ 18,440

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 commercial loans and leases receivable includes, but not limited to, commercial and industrial loans, agricultural loans, mortgage loans, promissory notes, interbank and other loans to financial institutions, draws against credit facilities, trade financing, lease financings. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. Excludes loans and leases covered under loss sharing agreements.

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Amount before allowance of revolving, open-end loan, extended under a line of credit and secured by the borrower's residential property. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. Excludes loans and leases covered under loss sharing agreements.

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Amount before allowance of consumer loans to acquire durable goods, including, but not limited to, automobiles, recreational vehicles, boats, refrigerators, washers and dryers. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. Excludes loans and leases covered under loss sharing agreements.

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Amount before allowance of consumer mortgage. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. Excludes subordinated loans such as home equity lines of credit and loans and leases covered under loss sharing agreements.

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Amount before allowance of other loans and leases not otherwise specified in the taxonomy. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. Excludes loans and leases 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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