Mortgage Servicing Assets - Schedule of Range and Weighted-Average of Significant Unobservable Inputs (Details) - Discounted cash flow - USD ($)	9 Months Ended
Sep. 30, 2025	Sep. 30, 2024
Commercial Mortgage Backed Securities \| Minimum
Servicing Assets at Fair Value [Line Items]
Expected defaults	1.00%	1.00%
Residual cash flows discount rate	7.02%	7.17%
Escrow earn rate	4.23%	4.51%
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	10.75%	10.72%
Escrow earn rate	4.37%	4.56%
Loan assumption rate	2.49%	2.36%
Commercial Mortgage Backed Securities \| Weighted Average
Servicing Assets at Fair Value [Line Items]
Expected defaults	1.01%	1.01%
Residual cash flows discount rate	10.47%	10.38%
Escrow earn rate	4.36%	4.51%
Loan assumption rate	2.00%	1.99%
Agency residential mortgage-backed securities \| Minimum
Servicing Assets at Fair Value [Line Items]
Prepayment speed	6.33%	7.08%
Residual cash flows discount rate	6.50%	6.50%
Servicing cost	$ 70.00	$ 70.00
Agency residential mortgage-backed securities \| Maximum
Servicing Assets at Fair Value [Line Items]
Prepayment speed	32.33%	53.34%
Residual cash flows discount rate	8.75%	8.75%
Servicing cost	$ 4,332	$ 3,582
Agency residential mortgage-backed securities \| Weighted Average
Servicing Assets at Fair Value [Line Items]
Prepayment speed	8.45%	8.33%
Residual cash flows discount rate	6.61%	6.60%
Servicing cost	$ 76.08	$ 75.25

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
-Section 50
-Paragraph 3
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-SubTopic 50
-Name Accounting Standards Codification
-Section 50
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-URI https://asc.fasb.org/1943274/2147481229/860-50-50-4

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