Mortgage Servicing Rights (Narrative) (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2017	Mar. 31, 2016	Dec. 31, 2016
Mortgage Servicing Rights [Abstract]
Residential Mortgage Loans Serviced	$ 2,550,000		$ 2,490,000
Contractually Specified Servicing Fees, Late Fees, and Ancillary Fees Earned in Exchange for Servicing Financial Assets	1,700	$ 1,400
Amortization of Mortgage Servicing Rights (MSRs)	1,350	1,268
Valuation allowance provision (reversal)	$ (4)	$ 1,874

Mortgage Servicing Rights [Abstract]

No definition available.

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- Definition

Unpaid principal balance of residential mortgage loans serviced for others at period end.

+ References

No definition available.

+ Details

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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 Accounting Standards Codification
-Topic 860
-SubTopic 50
-Section 50
-Paragraph 4
-Subparagraph (a)(4)
-URI http://asc.fasb.org/extlink&oid=68078379&loc=d3e122739-111746

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=66902209&loc=d3e3602-108585

+ Details

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- Definition

The total amount of contractually specified servicing fees, late fees, and ancillary fees earned for each period for which results of operations are presented.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 50
-Section 50
-Paragraph 2
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=68078379&loc=d3e122596-111746

+ Details

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- Definition

Amount of increase (decrease) in the valuation allowance for impairment of contract to service financial assets under which the benefits of servicing are expected to more than adequately compensate the servicer from expenses (recoveries) recognized.

+ References

+ Details

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