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Mortgage Servicing Assets - Assumptions and Sensitivity of MSR’s (Details) - Agency commercial mortgage-backed securities - USD ($) $ in Millions | 6 Months Ended | 12 Months Ended
--- | --- | ---
Jun. 30, 2026 | Dec. 31, 2025
Minimum |  |
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 | 4.42% | 3.94%
Residual cash flows discount rate | 7.01% | 6.96%
Expected defaults | 1.00% | 1.00%
Loan assumption rate | 8.00% | 8.00%
Maximum |  |
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 | 4.59% | 4.09%
Residual cash flows discount rate | 10.74% | 10.84%
Expected defaults | 1.50% | 2.00%
Loan assumption rate | 45.00% | 45.00%
Weighted Average |  |
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 | 4.58% | 4.08%
Effect on fair value from 10% adverse change | $ (32) | $ (29)
Effect on fair value from 20% adverse change | $ (65) | $ (57)
Residual cash flows discount rate | 10.46% | 10.58%
Effect on Fair Value of a 10% adverse change | $ (19) | $ (19)
Effect on Fair Value of a 20% adverse change | $ (37) | $ (36)
Expected defaults | 1.04% | 1.01%
Effect on fair value from 10% adverse change | $ (2) | $ (2)
Effect on fair value from 20% adverse change | $ (4) | $ (3)
Loan assumption rate | 9.78% | 10.05%
Effect on fair value from 10% adverse change | $ (7) | $ (6)
Effect on fair value from 20% adverse change | $ (14) | $ (13)

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- Definition Sensitivity Analysis of Fair Value, Transferor's Interests in Transferred Financial Assets, Impact of 10 Percent Adverse Change in Loan Assumptions 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, Escrow Earn Rate + References No definition available. + Details
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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 + 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 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 + Details
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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 + Details
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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 Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -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 + Details
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