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Mortgage Servicing Assets - Assumptions and Sensitivity of MSR’s (Details) - Agency commercial mortgage-backed securities $ in Millions | 12 Months Ended
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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)

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- Definition Assumption for Fair Value of Assets or Liabilities that relate to Transferor's Continuing Involvement, Default Rate + References No definition available. + Details
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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 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 + Details
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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 + 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 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 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 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 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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