Mortgage Servicing Assets - Schedule of Range and Weighted-Average of Significant Unobservable Inputs (Details) - Discounted cash flow - USD ($)	9 Months Ended
Sep. 30, 2023	Sep. 30, 2022
Commercial Mortgage Backed Securities \| Minimum
Servicing Assets at Fair Value [Line Items]
Expected defaults	1.00%	0.98%
Residual cash flows discount rate	7.44%	8.43%
Escrow earn rate	5.48%	3.69%
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	10.50%	10.17%
Escrow earn rate	5.61%	3.97%
Loan assumption rate	2.13%	1.50%
Commercial Mortgage Backed Securities \| Weighted Average
Servicing Assets at Fair Value [Line Items]
Expected defaults	1.01%	1.08%
Residual cash flows discount rate	10.13%	9.52%
Escrow earn rate	5.49%	3.87%
Loan assumption rate	1.96%	1.19%
Agency residential mortgage-backed securities \| Minimum
Servicing Assets at Fair Value [Line Items]
Residual cash flows discount rate	6.50%	7.50%
Prepayment speed	5.24%	7.05%
Servicing cost	$ 70.00	$ 62.00
Agency residential mortgage-backed securities \| Maximum
Servicing Assets at Fair Value [Line Items]
Residual cash flows discount rate	8.75%	8.53%
Prepayment speed	36.95%	44.74%
Servicing cost	$ 4,332	$ 4,375
Agency residential mortgage-backed securities \| Weighted Average
Servicing Assets at Fair Value [Line Items]
Residual cash flows discount rate	6.59%	7.53%
Prepayment speed	6.87%	8.09%
Servicing cost	$ 74.70	$ 66.59

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.

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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
-Topic 860
-SubTopic 50
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481229/860-50-50-2

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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

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 860
-SubTopic 50
-Name Accounting Standards Codification
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