Mortgage Servicing Rights - Assumptions (Details)	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018
Transfers and Servicing [Abstract]
Constant prepayment rate	11.20%	15.40%
Weighted-average life (years)	6 years 3 months	5 years 6 months
Yield to maturity discount	9.40%	10.50%

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

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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- 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

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- References

No definition available.

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