Loan Servicing (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2012	Dec. 31, 2011
Mortgage servicing rights, gross [Roll Forward]
Beginning balance	$ 30,409	$ 21,720
Originated servicing	19,727	14,330
Amortization	(10,180)	(5,641)
Ending balance	39,956	30,409
Allowance, mortgage servicing rights [Roll Forward]
Beginning balance	7,307	1,116
Additions	3,560	6,981
Recoveries	(3,331)	(790)
Ending balance	7,536	7,307
Mortgage servicing rights, net	$ 32,420	$ 23,102

Aggregate amount of servicing assets that are subsequently measured at fair value and servicing assets that are subsequently measured using the amortization method.

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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 of the servicing asset that has been amortized as of the balance sheet date.

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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 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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