LOANS AND ALLOWANCE FOR LOAN LOSSES (Narrative) (Details) (USD $)	3 Months Ended
Mar. 31, 2013	Mar. 31, 2012	Dec. 31, 2012
Accounts, Notes, Loans and Financing Receivable [Line Items]
Gain (loss) on sale of mortgage loans	$ 307,000	$ 319,000
Number of Contracts	35		30
Current Balance	6,472,000		5,868,000
Loans restructured due to credit difficulties that are now performing	5,500,000		4,700,000
Allowance for credit Losses related to troubled debt restructuring	542,000,000		494,000,000
Non-residential building operator loans expressed as a percentage of the total commercial real estate loans	30.00%
Lodging loans expressed as a percentage of the total commercial real estate loans	22.00%
Business Acquisition [Line Items]
Gross performing commercial loans acquired in business acquisition			6,000,000
Fair value mark recognized on commercial loans acquired in business acquisition			317,000,000
Fixed Rate Residential Mortgage
Accounts, Notes, Loans and Financing Receivable [Line Items]
Mortgage Loans sold on secondary market	9,400,000	5,400,000
Gain (loss) on sale of mortgage loans	307,000,000	319,000,000
Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Number of Contracts	4
Current Balance	$ 638,000,000

Allowance for Credit Losses, Related to Troubled Debt Restructured Loans

No definition available.

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- Definition

Gross commercial loans acquired in business acquisition.

+ References

No definition available.

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- Definition

Fair value mark recognized on commercial loans acquired in business acquisition.

+ References

No definition available.

+ Details

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- Definition

Lodging loans expressed as a percentage of the total commercial real estate loans.

+ References

No definition available.

+ Details

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- Definition

Non-residential building operator loans expressed as a percentage of the total commercial real estate loans.

+ References

No definition available.

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- Definition

Financing Receivables, Impaired, Troubled Debt Restructuring, Performing

+ References

No definition available.

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- Definition

Number of financing receivables that have been modified by troubled debt restructurings.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 33

-URI http://asc.fasb.org/extlink&oid=7512638&loc=SL6953676-111524

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- Definition

The amount of the outstanding recorded investment related to financing receivables that have been modified by troubled debt restructurings.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 40

-Section 50

-Paragraph 4

-URI http://asc.fasb.org/extlink&oid=6951948&loc=d3e18845-111554

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- Definition

The gains (losses) included in earnings that represent the difference between the sale price and the carrying value of loans made to finance real estate acquisitions. This element refers to the gain (loss) and not to the cash proceeds of the sale. This element is a noncash adjustment to net income when calculating net cash generated by operating activities using the indirect method.

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 95

-Paragraph 28

-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.

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 28

-Subparagraph (b)

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- Definition

The carrying amount of mortgage loans on real estate that were sold during the reporting period.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 948

-SubTopic 310

-Section S99

-Paragraph 1

-Subparagraph (SX 210.12-29.6)

-URI http://asc.fasb.org/extlink&oid=6589523&loc=d3e617274-123014

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-Name Accounting Standards Codification

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-SubTopic 10

-Section S99

-Paragraph 6

-Subparagraph (SX 210.5-04.(c) Schedule IV)

-URI http://asc.fasb.org/extlink&oid=6882300&loc=d3e5864-122674

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 29

-Article 12

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-Name Regulation S-X (SX)

-Number 210

-Section 04

-Paragraph c

-Subparagraph Schedule IV

-Article 5

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