Mortgage Servicing Rights (Economic Assumptions) (Details) - USD ($)	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Servicing Asset Key Economic Assumptions [Line Items]
Weighted average constant prepayment rate	19.38%	13.72%
Weighted average cost to service a loan	$ 87.30	$ 87.09
Fixed Rate Residential Mortgage
Servicing Asset Key Economic Assumptions [Line Items]
Discount rate	7.67%	8.92%
Discount rate, basis spread on Treasury rate	7.00%
All Loans and Leases, Excluding Conventional Fixed Loans
Servicing Asset Key Economic Assumptions [Line Items]
Discount rate	8.67%	9.92%
Discount rate, basis spread on Treasury rate	8.00%

Discount Rate, Basis Spread on Treasury Rate

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- Definition

[Line Items] for The key economic assumptions used to value servicing assets.

+ References

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- Definition

Servicing Assets and Servicing Liabilities at Fair Value, Assumptions Used to Estimate Fair Value, Cost to Service Loans, Per Loan

+ 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=116651436&loc=d3e122596-111746

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- Definition

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

+ References

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