Mortgage Servicing Assets - Schedule of Range and Weighted-Average of Significant Unobservable Inputs (Details) - Discounted cash flow - USD ($)	9 Months Ended
Sep. 30, 2022	Sep. 30, 2021
Commercial Mortgage Backed Securities \| Minimum
Servicing Assets at Fair Value [Line Items]
Expected defaults	0.98%	1.00%
Residual cash flows discount rate	8.43%	7.64%
Escrow earn rate	3.69%	1.04%
Loan assumption rate	0.00%	0.00%
Commercial Mortgage Backed Securities \| Maximum
Servicing Assets at Fair Value [Line Items]
Expected defaults	2.00%	2.00%
Residual cash flows discount rate	10.17%	10.49%
Escrow earn rate	3.97%	1.37%
Loan assumption rate	1.50%	1.71%
Commercial Mortgage Backed Securities \| Weighted Average
Servicing Assets at Fair Value [Line Items]
Expected defaults	1.08%	1.15%
Residual cash flows discount rate	9.52%	9.31%
Escrow earn rate	3.87%	1.04%
Loan assumption rate	1.19%	1.40%
Agency residential mortgage-backed securities \| Minimum
Servicing Assets at Fair Value [Line Items]
Residual cash flows discount rate	7.50%	7.50%
Prepayment speed	7.05%	8.03%
Servicing cost	$ 62.00	$ 62.00
Agency residential mortgage-backed securities \| Maximum
Servicing Assets at Fair Value [Line Items]
Residual cash flows discount rate	8.53%	8.57%
Prepayment speed	44.74%	48.88%
Servicing cost	$ 4,375	$ 4,375
Agency residential mortgage-backed securities \| Weighted Average
Servicing Assets at Fair Value [Line Items]
Residual cash flows discount rate	7.53%	7.54%
Prepayment speed	8.09%	11.67%
Servicing cost	$ 66.59	$ 68.15

Interest rate used to account for mortgage loan at fair value upon assumption.

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- Definition

Servicing Assets And Servicing Liabilities At Fair Value, Assumptions Used To Estimate Fair Value, Escrow Earn Rate

+ References

No definition available.

+ Details

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- Definition

Servicing Assets And Servicing Liabilities At Fair Value, Assumptions Used To Estimate Fair Value, Servicing Cost

+ References

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 https://asc.fasb.org/extlink&oid=128311188&loc=d3e122596-111746

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- Definition

Percentage of contractually collectible principal associated with a financial asset expected not to be collected due to default by the borrower.

+ References

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- Definition

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

+ References

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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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