LOANS - Commercial and Consumer Credit Exposure by Risk Attribute (Details) (USD $) In Thousands, unless otherwise specified	Sep. 30, 2014	Dec. 31, 2013
Financing Receivable, Recorded Investment [Line Items]
Commercial	$ 1,304,782	$ 1,035,668
Real Estate - Construction	193,776	80,741
Real Estate - Commercial	1,952,055	1,496,987
Lease financing	73,216	80,135
Total Commercial	3,523,829	2,693,531
Real Estate Residential	426,558	352,931
Installment	47,561	47,133
Home equity	416,099	376,454
Other	35,925	35,592
Total	926,143	812,110
Pass
Financing Receivable, Recorded Investment [Line Items]
Commercial	1,262,525	991,161
Real Estate - Construction	188,144	78,872
Real Estate - Commercial	1,867,535	1,422,215
Lease financing	71,314	80,135
Total Commercial	3,389,518	2,572,383
Special Mention
Financing Receivable, Recorded Investment [Line Items]
Commercial	23,592	23,053
Real Estate - Construction	3,830	65
Real Estate - Commercial	26,917	23,832
Lease financing	1,902	0
Total Commercial	56,241	46,950
Substandard
Financing Receivable, Recorded Investment [Line Items]
Commercial	18,665	21,454
Real Estate - Construction	1,802	1,804
Real Estate - Commercial	57,603	50,940
Lease financing	0	0
Total Commercial	78,070	74,198
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	419,862	344,325
Installment	47,163	46,559
Home equity	413,518	373,472
Other	35,925	35,592
Total	916,468	799,948
Nonperforming
Financing Receivable, Recorded Investment [Line Items]
Real Estate Residential	6,696	8,606
Installment	398	574
Home equity	2,581	2,982
Other	0	0
Total	$ 9,675	$ 12,162

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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