Mortgage Servicing Rights (Details) (USD $) In Thousands, unless otherwise specified	9 Months Ended
Sep. 30, 2012
Data and key economic assumptions related to mortgage servicing rights
Unpaid principle balance	$ 223,584
Weighted-average prepayment speed (CPR)	7.86%
Discount rate	11.53%
Weighted-average coupon interest rate	3.39%
Weighted-average servicing fee (basis points)	0.251%
Weighted-average remaining maturity (in months)	265 months 27 days
Estimated impact of 10% increase [Member]
Data and key economic assumptions related to mortgage servicing rights
Changes in weighted average prepayment speed relating to mortgage servicing rights	(76)
Changes in discount rates relating to mortgage servicing rights	(57)
Estimated impact of 20% increase [Member]
Data and key economic assumptions related to mortgage servicing rights
Changes in weighted average prepayment speed relating to mortgage servicing rights	(147)
Changes in discount rates relating to mortgage servicing rights	$ (110)

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Increase decrease in discount rates relating to mortgage servicing rights.

+ References

No definition available.

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- Definition

Increase decrease in weighted average prepayment speed relating to mortgage servicing rights.

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No definition available.

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- Definition

Value assumptions used to estimate fair value unpaid principle balance.

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No definition available.

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- Definition

Servicing assets and servicing liabilities at fair value assumptions used to estimate fair value weighted average coupon interest rate.

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No definition available.

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- Definition

Servicing assets and servicing liabilities at fair value assumptions used to estimate fair value weighted average remaining maturity.

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No definition available.

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- Definition

Servicing assets and servicing liabilities at fair value assumptions used to estimate fair value weighted average servicing fee.

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No definition available.

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- Definition

The discount rate used to estimate the fair value of servicing assets and servicing liabilities.

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 140

-Paragraph 17

-Subparagraph f

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

-Publisher FASB

-Name FASB Staff Position (FSP)

-Number FAS140-4/FIN46R-8

-Paragraph B8

-Subparagraph d

-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

The estimated speed of prepayments of principal on financial assets which may be one of the factors applied in estimating the fair value of servicing assets and servicing liabilities.

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+ Details

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