Loan Servicing - Activity for MSRs And Related Valuation Allowance (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Mortgage servicing rights:
Carrying amount, net, beginning of year	$ 9,013us-gaap_ServicingAssetAtAmortizedValue	$ 7,763us-gaap_ServicingAssetAtAmortizedValue	$ 9,301us-gaap_ServicingAssetAtAmortizedValue
Additions	1,026	2,436	3,399
Amortization	(1,631)	(2,479)	(3,634)
Change in valuation allowance	205	1,293	(1,303)
Carrying amount, net, end of year	8,613us-gaap_ServicingAssetAtAmortizedValue	9,013us-gaap_ServicingAssetAtAmortizedValue	7,763us-gaap_ServicingAssetAtAmortizedValue
Valuation allowance:
Beginning of year	1,031	2,324	1,021
Change in valuation allowance	(205)	(1,293)	1,303
End of year	$ 826	$ 1,031	$ 2,324

Amortized amount of contract to service financial assets under which the benefits of servicing are expected to more than adequately compensate the servicer.

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Amount of additions from purchases, assumption or transfer to contract to service financial assets under which the benefits of servicing are expected to more than adequately compensate the servicer.

+ References

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Amount of amortization of contract to service financial assets under which the benefits of servicing are expected to more than adequately compensate the servicer.

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Amount of valuation allowance applied to contract to service financial assets under which the benefits of servicing are expected to more than adequately compensate the servicer.

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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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New provisions recoveries or charged against this account which increase or reduce the net value of servicing assets.

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