LOANS (excluding covered loans) - Commercial and Consumer Credit Exposure by Risk Attribute (Details) (USD $) In Thousands, unless otherwise specified	Sep. 30, 2013	Dec. 31, 2012
Financing Receivable, Recorded Investment [Line Items]
Commercial	$ 960,016	$ 861,033
Real Estate - Construction	90,089	73,517
Real Estate - Commercial	1,493,969	1,417,008
Real Estate Residential	352,830	318,210
Installment	49,273	56,810
Home equity	373,839	367,500
Non Covered Loans
Financing Receivable, Recorded Investment [Line Items]
Commercial	960,016	861,033
Real Estate - Construction	90,089	73,517
Real Estate - Commercial	1,493,969	1,417,008
Total Commercial	2,544,074	2,351,558
Real Estate Residential	352,830	318,210
Installment	49,273	56,810
Home equity	373,839	367,500
Other	110,900	84,986
Total	886,842	827,506
Non Covered Loans \| Pass
Financing Receivable, Recorded Investment [Line Items]
Commercial	914,021	803,351
Real Estate - Construction	86,942	64,866
Real Estate - Commercial	1,391,039	1,307,370
Total Commercial	2,392,002	2,175,587
Non Covered Loans \| Special Mention
Financing Receivable, Recorded Investment [Line Items]
Commercial	29,061	29,663
Real Estate - Construction	225	65
Real Estate - Commercial	29,786	38,516
Total Commercial	59,072	68,244
Non Covered Loans \| Substandard
Financing Receivable, Recorded Investment [Line Items]
Commercial	16,934	28,019
Real Estate - Construction	2,922	8,586
Real Estate - Commercial	73,144	71,122
Total Commercial	93,000	107,727
Non Covered Loans \| Doubtful
Financing Receivable, Recorded Investment [Line Items]
Commercial	0	0
Real Estate - Construction	0	0
Real Estate - Commercial	0	0
Total Commercial	0	0
Non Covered Loans \| Performing
Financing Receivable, Recorded Investment [Line Items]
Real Estate Residential	343,484	310,341
Installment	48,852	56,358
Home equity	370,968	364,248
Other	110,814	84,490
Total	874,118	815,437
Non Covered Loans \| Nonperforming
Financing Receivable, Recorded Investment [Line Items]
Real Estate Residential	9,346	7,869
Installment	421	452
Home equity	2,871	3,252
Other	86	496
Total	$ 12,724	$ 12,069

Loans and Leases Receivable, Gross, Total of Commercial, Consumer Real Estate/Construction and Commercial Mortgage

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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 consumer real estate loans. Includes, but not limited to, construction financing, residential mortgage loans, and home equity lines of credit. 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 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 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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