Mortgage Servicing Rights - Valuation of Impairment (Details) - Mortgage loans - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Valuation Allowance for Impairment of Recognized Servicing Assets
Impairment reversals	$ 97	$ 136	$ 99
Permanent impairment charged against carrying value	$ 0	$ 0	$ 0

The charge against the valuation allowance related to a servicing asset that is subsequently measured using the amortization method.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 50
-Section 50
-Paragraph 4
-Subparagraph (e)(3)
-URI http://asc.fasb.org/extlink&oid=56950315&loc=d3e122739-111746

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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- Definition

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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 50
-Section 50
-Paragraph 4
-Subparagraph (e)(2)
-URI http://asc.fasb.org/extlink&oid=56950315&loc=d3e122739-111746

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