LOANS AND LEASES - Commercial and Consumer Credit Exposure by Risk Attribute (Details) - USD ($) $ in Thousands	Mar. 31, 2016	Dec. 31, 2015
Financing Receivable, Recorded Investment [Line Items]
Commercial	$ 1,744,732	$ 1,663,102
Real Estate - Construction	341,453	311,712
Real Estate - Commercial	2,261,857	2,258,297
Lease financing	101,135	93,986
Total Commercial	4,449,177	4,327,097
Real Estate Residential	508,512	512,311
Home equity	466,010	466,629
Loans and Leases Receivable, Gross, Consumer, Installment, Durable Goods	41,627	41,506
Other	39,283	41,217
Total	1,055,432	1,061,663
Pass
Financing Receivable, Recorded Investment [Line Items]
Commercial	1,680,764	1,596,415
Real Estate - Construction	337,472	310,806
Real Estate - Commercial	2,182,683	2,179,701
Lease financing	99,583	93,236
Total Commercial	4,300,502	4,180,158
Special Mention
Financing Receivable, Recorded Investment [Line Items]
Commercial	22,155	27,498
Real Estate - Construction	3,417	128
Real Estate - Commercial	19,754	19,903
Lease financing	0	0
Total Commercial	45,326	47,529
Substandard
Financing Receivable, Recorded Investment [Line Items]
Commercial	41,813	39,189
Real Estate - Construction	564	778
Real Estate - Commercial	59,420	58,693
Lease financing	1,552	750
Total Commercial	103,349	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
Performing
Financing Receivable, Recorded Investment [Line Items]
Real Estate Residential	499,849	503,317
Home equity	460,341	461,188
Loans and Leases Receivable, Gross, Consumer, Installment, Durable Goods	41,408	41,253
Other	39,283	41,217
Total	1,040,881	1,046,975
Nonperforming
Financing Receivable, Recorded Investment [Line Items]
Real Estate Residential	8,663	8,994
Home equity	5,669	5,441
Loans and Leases Receivable, Gross, Consumer, Installment, Durable Goods	219	253
Other	0	0
Total	$ 14,551	$ 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.

+ References

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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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