LOANS (excluding covered loans) - Commercial and Consumer Credit Exposure by Risk Attribute (Detail) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2011	Dec. 31, 2010
Financing Receivable, Recorded Investment [Line Items]
Commercial	$ 856,981	$ 800,253
Real Estate - Construction	114,974	163,543
Real Estate - Commercial	1,233,067	1,139,931
Real Estate Residential	287,980	269,173
Installment	67,543	69,711
Home equity	358,960	341,310
Non Covered Loans
Financing Receivable, Recorded Investment [Line Items]
Commercial	856,981	800,253
Real Estate - Construction	114,974	163,543
Real Estate - Commercial	1,233,067	1,139,931
Loans and Leases Rec, Gross, Total Commercial, Consumer RE and Comm Mortgage	2,205,022	2,103,727
Real Estate Residential	287,980	269,173
Installment	67,543	69,711
Home equity	358,960	341,310
Other	48,942	32,172
Total	763,425	712,366
Non Covered Loans \| Pass
Financing Receivable, Recorded Investment [Line Items]
Commercial	799,471	731,932
Real Estate - Construction	89,072	115,988
Real Estate - Commercial	1,110,718	979,023
Loans and Leases Rec, Gross, Total Commercial, Consumer RE and Comm Mortgage	1,999,261	1,826,943
Non Covered Loans \| Special Mention
Financing Receivable, Recorded Investment [Line Items]
Commercial	37,547	36,453
Real Estate - Construction	1,751	4,829
Real Estate - Commercial	28,994	63,618
Loans and Leases Rec, Gross, Total Commercial, Consumer RE and Comm Mortgage	68,292	104,900
Non Covered Loans \| Substandard
Financing Receivable, Recorded Investment [Line Items]
Commercial	19,435	31,557
Real Estate - Construction	24,151	42,726
Real Estate - Commercial	93,355	97,290
Loans and Leases Rec, Gross, Total Commercial, Consumer RE and Comm Mortgage	136,941	171,573
Non Covered Loans \| Doubtful
Financing Receivable, Recorded Investment [Line Items]
Commercial	528	311
Real Estate - Construction	0	0
Real Estate - Commercial	0	0
Loans and Leases Rec, Gross, Total Commercial, Consumer RE and Comm Mortgage	528	311
Non Covered Loans \| Performing
Financing Receivable, Recorded Investment [Line Items]
Real Estate Residential	279,958	262,654
Installment	67,136	69,561
Home equity	356,887	338,757
Other	48,942	32,172
Total	752,923	703,144
Non Covered Loans \| Nonperforming
Financing Receivable, Recorded Investment [Line Items]
Real Estate Residential	8,022	6,519
Installment	407	150
Home equity	2,073	2,553
Other	0	0
Total	$ 10,502	$ 9,222

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

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Reflects the sum of the gross carrying amounts of the various categories of unpaid commercial loans and leases receivable, primarily issued to businesses. Includes: (1) commercial and industrial loans, consisting of general purpose loans to entities involved in producing, transporting, or merchandising products sold in the course of commerce; (2) agricultural loans consisting of borrowings used to finance major equipment and machinery purchases and expenses, livestock or crop production (including fisheries), and to supplement working capital needs of an entity engaged in farming operations; (3) mortgage loans secured by a [legal] security interest in real property [commercial building or business real property]; (4) obligation in the form of [promissory] notes, used for the funding of construction projects; (5) interbank and other loans to financial institutions for the purpose of liquidity management on the part of the borrower; (6) draws against credit facilities provided to companies involved in mortgage banking activities (warehousing); (7) amounts lent to businesses engaged in international activities (trade financing); (8) lease financings; and (9) loans to governmental entities.

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Reflects the sum of the gross carrying amounts of the various categories of loans made to individuals for personal needs, including mortgage, home equity, vehicles, credit card, installment, and lease financing.

+ References

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Gross amount under revolving lines of credit outstanding extended to a homeowner and collateralized by the equity in the home. Such lines of credit are generally subordinated to the homeowner's mortgage loan or loans. Loan proceeds are generally unrestricted as to use by the borrower.

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Reflects the gross carrying amount of unpaid loans issued to individuals to acquire goods that are expected to have a useful life greater than a year, including automobiles, recreational vehicles, boats, refrigerators, washers and dryers. The loans generally are secured by the asset purchased and are typically repaid monthly in installments of principal and interest.

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The gross carrying amount of mortgage loans to individuals. This item excludes subordinated loans such as home equity lines of credit.

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The total gross amount of money lent to individual customers including construction financing, residential mortgage loans, and home equity lines of credit.

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The gross amount of other loans and leases not otherwise specified in the taxonomy.

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Reflects the gross carrying amount of unpaid loans issued to businesses to provide financing on existing land or a building, which, pursuant to terms of the underlying debt instrument, are secured at a minimum but possibly exclusively by that real property. Mortgages represent permanent financing, and are issued to replace previously existing mortgages or pay off acquisition, development and construction loans, or to provide cash to the borrower.

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