Mortgage Servicing Rights (Schedule of Servicing Assets at Fair Value) (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Mortgage Servicing Rights [Abstract]
Beginning balance	$ 730	$ 933	$ 1,190
Originations			10
Amortization	(272)	(203)	(267)
Ending balance	458	730	933
Beginning balance	(362)	(330)	(476)
Valuation charges	(16)	(81)	(48)
Valuation reversals	155	49	194
Ending balance	(223)	(362)	(330)
Mortgage servicing rights cost	458	730	933
Valuation allowance	(223)	(362)	(330)
Carrying value	235	368	603
Fair value	$ 235	$ 368	$ 603
Weighted average discount rate	10.50%	10.00%	10.00%
Weighted average prepayment speed	21.74%	21.85%	15.55%

Servicing Asset At Carrying Amount

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- Definition

Discount rate which is used to value residual cash flows generated by financial assets of the securitization, asset-backed financing arrangement, or similar transfer for initial fair value measurement.

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Estimated rate of prepayment of principal on financial assets for initial fair value measurement.

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Amortized carrying amount (balance) 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.

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The value of new servicing assets, subsequently measured at amortized value, acquired or created during the current period through purchases or from transfers of financial assets.

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Amount of expense charged against earnings for the periodic recognition of servicing assets relative to estimated net servicing income.

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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.

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Reflects the estimated amount of impairment as of the balance sheet date of recognized servicing assets that are being amortized in proportion to and over the period of estimated net servicing income or loss.

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This item represents the contra-account activity for provisions recognized for impairments of servicing assets which is offset against the value of servicing assets to arrive at a net carrying value as of the date of the statement of financial position.

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This item represents the contra-account activity for recoveries recognized for impairments of servicing assets which is offset against the value of servicing assets to arrive at a net carrying value as of the date of the statement of financial position.

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