LOANS (excluding covered loans) - Loan Delinquency, including Nonaccrual Loans (Detail) (USD $)	Sep. 30, 2011	Dec. 31, 2010
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total	$ 2,937,661,000	$ 2,816,093,000
Non Covered Loans
Financing Receivable, Recorded Investment, Past Due [Line Items]
30 - 59 days past due	19,814,000	16,950,000
60 - 89 days past due	10,544,000	11,880,000
> 90 days past due	47,328,000	44,875,000
Total Past due	77,686,000	73,705,000
Current	2,859,975,000	2,742,388,000
Total	2,937,661,000	2,816,093,000
> 90 days past due and still accruing	235,000	370,000
Non Covered Loans \| Commercial
Financing Receivable, Recorded Investment, Past Due [Line Items]
30 - 59 days past due	2,019,000	2,241,000
60 - 89 days past due	852,000	1,573,000
> 90 days past due	10,436,000	11,684,000
Total Past due	13,307,000	15,498,000
Current	809,245,000	784,755,000
Total	822,552,000	800,253,000
> 90 days past due and still accruing	0	0
Non Covered Loans \| Real estate-construction
Financing Receivable, Recorded Investment, Past Due [Line Items]
30 - 59 days past due	4,000,000	1,754,000
60 - 89 days past due	6,254,000	3,782,000
> 90 days past due	12,197,000	8,973,000
Total Past due	22,451,000	14,509,000
Current	114,200,000	149,034,000
Total	136,651,000	163,543,000
> 90 days past due and still accruing	0	0
Non Covered Loans \| Real estate-commercial
Financing Receivable, Recorded Investment, Past Due [Line Items]
30 - 59 days past due	4,316,000	3,202,000
60 - 89 days past due	1,569,000	3,979,000
> 90 days past due	15,731,000	16,435,000
Total Past due	21,616,000	23,616,000
Current	1,180,419,000	1,116,315,000
Total	1,202,035,000	1,139,931,000
> 90 days past due and still accruing	0	0
Non Covered Loans \| Real estate-residential
Financing Receivable, Recorded Investment, Past Due [Line Items]
30 - 59 days past due	7,827,000	7,671,000
60 - 89 days past due	1,362,000	1,930,000
> 90 days past due	6,757,000	5,127,000
Total Past due	15,946,000	14,728,000
Current	284,219,000	254,445,000
Total	300,165,000	269,173,000
> 90 days past due and still accruing	0	0
Non Covered Loans \| Installment
Financing Receivable, Recorded Investment, Past Due [Line Items]
30 - 59 days past due	275,000	456,000
60 - 89 days past due	86,000	48,000
> 90 days past due	207,000	120,000
Total Past due	568,000	624,000
Current	69,466,000	69,087,000
Total	70,034,000	69,711,000
> 90 days past due and still accruing	0	0
Non Covered Loans \| Home equity
Financing Receivable, Recorded Investment, Past Due [Line Items]
30 - 59 days past due	1,112,000	1,260,000
60 - 89 days past due	258,000	392,000
> 90 days past due	1,765,000	2,166,000
Total Past due	3,135,000	3,818,000
Current	359,784,000	337,492,000
Total	362,919,000	341,310,000
> 90 days past due and still accruing	0	0
Non Covered Loans \| All other
Financing Receivable, Recorded Investment, Past Due [Line Items]
30 - 59 days past due	265,000	366,000
60 - 89 days past due	163,000	176,000
> 90 days past due	235,000	370,000
Total Past due	663,000	912,000
Current	42,642,000	31,260,000
Total	43,305,000	32,172,000
> 90 days past due and still accruing	$ 235,000	$ 370,000

Financing receivables that are less than 60 days past due but more than 29 days past due.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 7A

-URI http://asc.fasb.org/extlink&oid=6965416&loc=SL6953401-111524

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Financing receivables that are less than 90 days past due but more than 59 days past due.

+ References

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- Definition

Recorded investment in financing receivables that are 90 days or more past due and still accruing.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 7

-URI http://asc.fasb.org/extlink&oid=6965416&loc=d3e5111-111524

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- Definition

Financing receivables that are current.

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Financing receivables that are equal to or greater than 90 days past due.

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- Definition

Recorded Investment in financing receivables that are past due at the balance sheet date.

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- Definition

Reflects the aggregate gross carrying amount of all categories of loans and leases held in portfolio, after deducting deferred income, but before deducting the allowance for losses on loans and leases.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 4

-URI http://asc.fasb.org/extlink&oid=6965416&loc=d3e5074-111524

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 45

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6375948&loc=d3e4428-111522

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher AICPA

-Name Statement of Position (SOP)

-Number 01-6

-Paragraph 13

-Subparagraph e

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher AICPA

-Name Audit and Accounting Guide (AAG)

-Number AAG-DEP

-Chapter 8

-Paragraph 116

-IssueDate 2006-05-01

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 5: http://www.xbrl.org/2003/role/presentationRef

-Publisher OTS

-Name Federal Regulation (FR)

-Number Title 12

-Chapter V

-Section 563c.102

-Paragraph 8

-Subparagraph e

-Subsection I

-LegacyDoc This is a non-GAAP reference that was included in the 2009 taxonomy. It will be removed from future versions of this taxonomy.

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