Mortgage Servicing Rights - Key Assumptions Used in Calculating Fair Value of Residential Mortgage Servicing Rights (Details) (Mortgage Servicing Rights Residential, USD $)	9 Months Ended	12 Months Ended
Sep. 30, 2014	Dec. 31, 2013
Servicing Assets at Fair Value [Line Items]
Expected weighted average life	88 months	93 months
Constant prepayment speed	8.40%	8.30%
Discount rate	10.00%	10.50%
Primary mortgage rate to refinance	4.20%	4.50%
Current
Servicing Assets at Fair Value [Line Items]
Cost to service per loan per year	$ 63	$ 53
30-59 days or less delinquent
Servicing Assets at Fair Value [Line Items]
Cost to service per loan per year	213	103
60-89 days delinquent
Servicing Assets at Fair Value [Line Items]
Cost to service per loan per year	313	203
90-119 days delinquent
Servicing Assets at Fair Value [Line Items]
Cost to service per loan per year	413	303
120 days or more delinquent
Servicing Assets at Fair Value [Line Items]
Cost to service per loan per year	$ 563	$ 553

Cost to service per loan per year.

No definition available.

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- Definition

The stated interest rate on the mortgage loan receivable or the weighted average interest rate on a group of loans.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 205

-SubTopic 10

-Section S99

-Paragraph 6

-Subparagraph (SX 210.5-04.(c) Schedule IV)

-URI http://asc.fasb.org/extlink&oid=27047687&loc=d3e5864-122674

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 29

-Article 12

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 04

-Paragraph c

-Subparagraph Schedule IV

-Article 5

Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 948

-SubTopic 310

-Section S99

-Paragraph 1

-Subparagraph (SX 210.12-29)

-URI http://asc.fasb.org/extlink&oid=6589523&loc=d3e617274-123014

+ Details

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- Definition

Discount rate used to estimate the fair value of servicing assets and servicing liabilities.

+ 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 (d)

-URI http://asc.fasb.org/extlink&oid=7882072&loc=d3e122596-111746

+ Details

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- Definition

Estimated rate of prepayments of principal on servicing assets and servicing liabilities.

+ References

+ Details

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- Definition

Weighted average life of financial assets and financial liabilities, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

+ Details

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