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Mortgage Servicing Assets - Narrative (Details) - USD ($) $ in Millions | 6 Months Ended
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Jun. 30, 2026 | Jun. 30, 2025
Agency commercial mortgage-backed securities |  |
Servicing Assets at Fair Value [Line Items] |  |
Contractual fee income from servicing commercial mortgage loans | $ 174 | $ 209
Amortization of servicing commercial mortgage loans | 63 | 62
Residential mortgage-backed securities |  |
Servicing Assets at Fair Value [Line Items] |  |
Contractual fee income from servicing commercial mortgage loans | 17 | 20
Amortization of servicing commercial mortgage loans | $ 7 | $ 6

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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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- 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 -Subparagraph (a)(4)(i) -Publisher FASB -URI https://asc.fasb.org/1943274/2147481229/860-50-50-3 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 860 -SubTopic 50 -Name Accounting Standards Codification -Section 50 -Paragraph 3 -Subparagraph (a)(1) -Publisher FASB -URI https://asc.fasb.org/1943274/2147481229/860-50-50-3 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Topic 860 -SubTopic 50 -Name Accounting Standards Codification -Section 50 -Paragraph 3 -Subparagraph (a)(2) -Publisher FASB -URI https://asc.fasb.org/1943274/2147481229/860-50-50-3 Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Topic 860 -SubTopic 50 -Name Accounting Standards Codification -Section 50 -Paragraph 3 -Subparagraph (a)(3) -Publisher FASB -URI https://asc.fasb.org/1943274/2147481229/860-50-50-3 Reference 5: http://www.xbrl.org/2003/role/disclosureRef -Topic 860 -SubTopic 50 -Name Accounting Standards Codification -Section 50 -Paragraph 4 -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org/1943274/2147481229/860-50-50-4 + Details
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