Fair Value Measurements (Details Textuals) (USD $)	3 Months Ended
Sep. 30, 2012	Dec. 31, 2011	Sep. 30, 2011
Fair Value Measurements (Textuals) [Abstract]
Other real estate owned measured at fair value	$ 34,000,000	$ 54,000,000
Write down of Other Real Estate Owned	8,000,000	9,000,000	7,000,000
Notional amount of cash flow hedge interest rate swap agreements	0	100,000,000
Commitment on standby letters of credit	$ 300,000,000	$ 300,000,000
Weighted average constant prepayment rate	24.40%
Fair Value, Option, Quantitative Disclosures [Line Items]
Closing ratio	77.00%
Weighted average discount rate	9.70%
MaximumMember
Fair Value, Option, Quantitative Disclosures [Line Items]
3 month LIBOR forward range	3.07%
Weighted average discount rate	50.00%
MinimumMember
Fair Value, Option, Quantitative Disclosures [Line Items]
3 month LIBOR forward range	0.35%
Weighted average discount rate	0.00%

Represents the percentage of loans currently in a lock position which management estimates will ultimately close.

No definition available.

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- Definition

Other real estate owned fair value disclosure.

+ References

No definition available.

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- Definition

Discount rate which is used to value residual cash flows generated by financial assets of a securitization, asset-backed financing arrangement, or similar transfer regardless of when the transfer occurred.

+ References

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

-Publisher FASB

-Name FASB Staff Position (FSP)

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-Paragraph B11

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-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 140

-Paragraph 17

-Subparagraph i(2)

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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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- Definition

Estimated rate of prepayment of principal on financial assets regardless of when the transfer occurred.

+ References

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-Publisher FASB

-Name FASB Staff Position (FSP)

-Number FAS140-4/FIN46(R)-8

-Paragraph B11

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-Name Statement of Financial Accounting Standard (FAS)

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- Definition

Interest rate used to find the present value of an amount to be paid or received in the future as an input to measure fair value. For example, but not limited to, weighted average cost of capital (WACC), cost of capital, cost of equity and cost of debt.

+ References

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- Definition

The total amount of the contingent obligation under letters of credit outstanding as of the reporting date.

+ References

No definition available.

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- Definition

Aggregate notional amount of all interest rate derivatives designated as hedging instruments in cash flow hedges. Notional amount refers to the monetary amount specified in the interest rate derivative contract.

+ References

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-Glossary Notional Amount

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- Definition

The amount of any write-down or reserve provided in the period on a real estate investment.

+ References

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