Other Assets - Quantitative Assumptions Used for MSRs (Details)	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019
Minimum
Quantitative assumptions used in determining lower of cost or fair value of MSRs
Conditional prepayment rate (as a percent)	11.86%	10.74%
Life in years (of the MSR)	1 year 9 months 29 days	2 years 14 days
Weighted-average coupon rate (as a percent)	3.24%	3.96%
Discount rate (as a percent)	10.00%	10.00%
Maximum
Quantitative assumptions used in determining lower of cost or fair value of MSRs
Conditional prepayment rate (as a percent)	26.52%	23.39%
Life in years (of the MSR)	6 years 8 months 4 days	6 years 3 months 29 days
Weighted-average coupon rate (as a percent)	6.98%	7.26%
Discount rate (as a percent)	10.00%	10.01%
Weighted Average
Quantitative assumptions used in determining lower of cost or fair value of MSRs
Conditional prepayment rate (as a percent)	16.90%	11.10%
Life in years (of the MSR)	4 years 5 months 12 days	5 years 11 months 26 days
Weighted-average coupon rate (as a percent)	3.84%	4.01%
Discount rate (as a percent)	10.00%	10.00%

Weighted average coupon rate used to estimate the fair value of servicing assets and servicing liabilities.

No definition available.

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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/exampleRef
-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

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-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

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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