Mortgage Servicing Assets - Assumptions and Sensitivity of MSR’s (Details) - Agency commercial mortgage-backed securities $ in Millions	12 Months Ended
Dec. 31, 2025 USD ($)
Sensitivity Analysis of Fair Value of Interests Continued to be Held by Transferor, Servicing Assets or Liabilities, Impact of Adverse Change in Assumption [Line Items]
Escrow earn rate assumptions	4.08%
Effect on fair value from 10% adverse change	$ (29)
Effect on fair value from 20% adverse change	$ (57)
Discount rate assumptions	10.58%
Effect on Fair Value of a 10% adverse change	$ (19)
Effect on Fair Value of a 20% adverse change	$ (36)
Default rate assumptions	1.01%
Effect on fair value from 10% adverse change	$ (2)
Effect on fair value from 20% adverse change	$ (3)
Prepayment rate assumptions	10.05%
Effect on Fair Value of a 10% adverse change	$ (6)
Effect on fair value from 20% adverse change	$ (13)

Assumption for Fair Value of Assets or Liabilities that relate to Transferor's Continuing Involvement, Default Rate

No definition available.

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- Definition

Assumption for Fair Value of Assets or Liabilities that relate to Transferor's Continuing Involvement, Escrow Earn Rate

+ References

No definition available.

+ Details

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- Definition

Sensitivity Analysis of Fair Value, Transferor's Interests in Transferred Financial Assets, Impact of 10 Percent Adverse Change in Default Rate

+ References

No definition available.

+ Details

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- Definition

Sensitivity Analysis of Fair Value, Transferor's Interests in Transferred Financial Assets, Impact of 10 Percent Adverse Change in Escrow Earn Rate

+ References

No definition available.

+ Details

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- Definition

Sensitivity Analysis of Fair Value, Transferor's Interests in Transferred Financial Assets, Impact of 20 Percent Adverse Change in Default Rate

+ References

No definition available.

+ Details

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- Definition

Sensitivity Analysis of Fair Value, Transferor's Interests in Transferred Financial Assets, Impact of 20 Percent Adverse Change in Escrow Earn Rate

+ References

No definition available.

+ Details

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- Definition

Discount rate which is used to value residual cash flows generated by financial assets of a securitization, asset-backed financing arrangement, or similar transfer regardless of when the transfer occurred.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 860
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 4
-Subparagraph (b)(1)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481326/860-20-50-4

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- Definition

Estimated rate of prepayment of principal on financial assets regardless of when the transfer occurred.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 860
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 4
-Subparagraph (b)(2)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481326/860-20-50-4

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- Definition

The hypothetical financial impact of a 10 percent adverse change of the discount rate on the fair value of transferor's interests in transferred financial assets (including any servicing assets or servicing liabilities) as of the balance sheet date.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 860
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 4
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481326/860-20-50-4

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- Definition

The hypothetical financial impact of a 10 percent adverse change of prepayment speed on the fair value of transferor's interests in transferred financial assets (including any servicing assets or servicing liabilities) as of the balance sheet date.

+ References

+ Details

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- Definition

The hypothetical financial impact of a 20 percent adverse change of the discount rate on the fair value of transferor's interests in transferred financial assets (including any servicing assets or servicing liabilities) as of the balance sheet date.

+ 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 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 4
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481326/860-20-50-4

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- Definition

The hypothetical financial impact of a specified adverse percentage change in prepayment speed on the fair value of transferor's interests in transferred financial assets (including any servicing assets or servicing liabilities) as of the balance sheet date.

+ References

+ Details

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