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Mortgage Servicing Assets - Additional Information (Details) - USD ($) $ in Millions | 12 Months Ended
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Dec. 31, 2025 | Dec. 31, 2024 | Dec. 31, 2023
Agency commercial mortgage-backed securities |  |  |
Servicing Assets at Fair Value [Line Items] |  |  |
Contractual fee income | $ 400 | $ 382 | $ 314
Amortization of mortgage servicing rights | 125 | 124 | 123
Agency residential mortgage-backed securities |  |  |
Servicing Assets at Fair Value [Line Items] |  |  |
Contractual fee income | 41 | 40 | 38
Amortization of mortgage servicing rights | $ 12 | $ 11 | $ 9

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- Definition Fees and commissions, mortgage banking and servicing before amortization. + References No definition available. + Details
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- Definition The periodic amortization (in proportion to and over the period of estimated net servicing income or loss) of capitalized servicing rights, which contractually entitle the servicer to receive fees and ancillary revenues for performing billing, collection, disbursement and recordkeeping services in connection with a mortgage portfolio. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Section 45 -Paragraph 28 -Subparagraph (b) -SubTopic 10 -Topic 230 -Publisher FASB -URI https://asc.fasb.org/1943274/2147482740/230-10-45-28 Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 860 -SubTopic 50 -Name Accounting Standards Codification -Section 50 -Paragraph 4 -Subparagraph (a)(4) -Publisher FASB -URI https://asc.fasb.org/1943274/2147481229/860-50-50-4 + Details
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