LOANS - Commercial and Consumer Credit Exposure by Risk Attribute (Details) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014
Financing Receivable, Recorded Investment [Line Items]
Commercial	$ 1,298,874	$ 1,315,114
Real Estate - Construction	227,969	197,571
Real Estate - Commercial	2,120,084	2,140,667
Lease financing	81,796	77,567
Total Commercial	3,728,723	3,730,919
Real Estate Residential	496,852	501,894
Installment	43,798	47,320
Home equity	456,278	458,627
Other	37,886us-gaap_LoansAndLeasesReceivableOther	38,475us-gaap_LoansAndLeasesReceivableOther
Total	1,034,814	1,046,316
Pass
Financing Receivable, Recorded Investment [Line Items]
Commercial	1,250,649	1,265,116
Real Estate - Construction	226,090	195,787
Real Estate - Commercial	2,005,998	2,027,897
Lease financing	80,218	75,839
Total Commercial	3,562,955	3,564,639
Special Mention
Financing Receivable, Recorded Investment [Line Items]
Commercial	27,689	30,903
Real Estate - Construction	136	0
Real Estate - Commercial	26,119	25,928
Lease financing	1,453	1,728
Total Commercial	55,397	58,559
Substandard
Financing Receivable, Recorded Investment [Line Items]
Commercial	20,536	19,095
Real Estate - Construction	1,743	1,784
Real Estate - Commercial	87,967	86,842
Lease financing	125	0
Total Commercial	110,371	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	486,466	490,314
Installment	43,458	46,806
Home equity	450,733	452,281
Other	37,886	38,475
Total	1,018,543	1,027,876
Nonperforming
Financing Receivable, Recorded Investment [Line Items]
Real Estate Residential	10,386	11,580
Installment	340	514
Home equity	5,545	6,346
Other	0	0
Total	$ 16,271	$ 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 consumer loans, including, but not limited to, mortgage, home equity, vehicles, credit card, installment, and lease financing. 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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