Mortgage Servicing Rights (Details) (USD $)	3 Months Ended
Mar. 31, 2012	Mar. 31, 2011	Dec. 31, 2011
Mortgage Servicing Rights [Abstract]
Moving average of weekly prepayment data (in months)	3
Anticipated loan prepayment rate of servicing assets (in hundredths)	30.76%
Period used to determine average quarterly discount rate (in years)	10
Servicing assets and servicing liabilities at fair value, assumptions used to estimate fair value, discount rate adjustment factor (in hundredths)	4.91%
Mortgage servicing rights capitalized	$ 11,000	$ 198,000
Amortization of mortgage servicing rights	172,000	154,000
Fair value of mortgage servicing rights	994,000	2,205,000	1,581,000
Outstanding principal balance of loans serviced for others	221,694,000	254,519,000	238,221,000
Summary of mortgage servicing rights [Abstract]
Mortgage servicing rights	6,110,000	5,927,000	6,099,000
Accumulated amortization	(5,009,000)	(4,417,000)	(4,837,000)
Impairment reserve	(300,000)	(20,000)	(61,000)
Mortgage servicing rights	$ 801,000	$ 1,490,000	$ 1,201,000

The cumulative amount of amortization for mortgage servicing rights that has been recognized in the income statement.

No definition available.

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- Definition

The average quarterly discount rate period used as assumption in evaluating the carrying value of mortgage servicing rights.

+ References

No definition available.

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- Definition

Gross amount, as of the balance sheet date, of mortgage servicing rights.

+ References

No definition available.

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- Definition

Net amount, as of the balance sheet date, of mortgage servicing rights.

+ References

No definition available.

+ Details

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- Definition

The moving average period of weekly prepayment data used as assumption in evaluating the carrying value of mortgage servicing rights.

+ References

No definition available.

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- Definition

A reserve for the amount of expected decrease in the value of mortgage servicing rights which cannot be physically measured.

+ References

No definition available.

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- Definition

Dollar amount of principal outstanding on loans being serviced for others at the balance sheet date.

+ References

No definition available.

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- Definition

The amount of rate spread added to the ten-year US Treasury rate to derive the discount rate used in the fair value calculation for the loan servicing portfolio.

+ References

No definition available.

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- Definition

The periodic amortization (in proportion to and over the period of estimated net servicing income or loss) of capitalized servicing rights, which contractually entitle the servicer to receive fees and ancillary revenues for performing billing, collection, disbursement and recordkeeping services in connection with a mortgage portfolio. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 140

-Paragraph 17

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-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

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- Definition

The increase during the reporting period in the cumulative value of servicing rights. This increase is the result of new servicing rights that are created when mortgages are sold or transferred.

+ 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.

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

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- Definition

Fair value as of the balance sheet date of an asset representing net future revenues from contractually specified servicing fees, late charges, and other ancillary revenues, in excess of future costs related to servicing arrangements.

+ References

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

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-Name FASB Staff Position (FSP)

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-Paragraph B9

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

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-Name Statement of Financial Accounting Standard (FAS)

-Number 140

-Paragraph 13A, 13B

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-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.

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 140

-Paragraph 17

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-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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