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Mortgage Servicing Rights (Economic Assumptions) (Details) - $ / loans | 9 Months Ended | 12 Months Ended
--- | --- | ---
Sep. 30, 2019 | Dec. 31, 2018
Servicing Asset Key Economic Assumptions [Line Items] |  |
Weighted average constant prepayment rate | 14.15% | 9.26%
Weighted average cost to service a loan | 87.09 | 87.52
Fixed Rate Residential Mortgage |  |
Servicing Asset Key Economic Assumptions [Line Items] |  |
Discount rate | 8.67% | 9.69%
All Loans and Leases, Excluding Conventional Fixed Loans |  |
Servicing Asset Key Economic Assumptions [Line Items] |  |
Discount rate | 9.67% | 10.69%

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- Definition [Line Items] for The key economic assumptions used to value servicing assets. + References No definition available. + Details
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- Definition Servicing Assets and Servicing Liabilities at Fair Value, Assumptions Used to Estimate Fair Value, Cost to Service Loans + References No definition available. + Details
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- Definition Discount rate used to estimate the fair value of servicing assets and servicing liabilities. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 860 -SubTopic 50 -Section 50 -Paragraph 2 -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=68078379&loc=d3e122596-111746 + Details
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- Definition Estimated rate of prepayments of principal on servicing assets and servicing liabilities. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 860 -SubTopic 50 -Section 50 -Paragraph 2 -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=68078379&loc=d3e122596-111746 + Details
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- Details
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