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LOAN SERVICING - Schedule of Sensitivity of Fair Value to Changes in Key Assumptions (Details) - Mortgage Servicing Rights - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2025 | Dec. 31, 2024
Servicing Assets at Fair Value [Line Items] |  |
Weighted average life (months) | 89 months | 96 months
Constant prepayment rate (annualized) | 8.60% | 7.60%
Discount rate | 10.10% | 10.30%
Sensitivity analysis of fair value, change in interest rates, plus 2.00% | $ 13 | $ 6
Sensitivity analysis of fair value, change in interest rates, plus 1.00% | 10 | 5
Sensitivity analysis of fair value, change in interest rates, plus .50% | 7 | 3
Sensitivity analysis of fair value, change in interest rates, plus .25% | 4 | 2
Sensitivity analysis of fair value, change in interest rates, minus .25% | (4) | (2)
Sensitivity analysis of fair value, change in interest rates, minus .50% | (8) | (5)
Sensitivity analysis of fair value, change in interest rates, minus 1.00% | (14) | (11)
Sensitivity analysis of fair value, change in interest rates, minus 2.00% | (24) | (20)
Sensitivity analysis of fair value, change in interest rates, minus 3.00% | $ (42) | $ (34)

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- Definition Discount rate which is used to value residual cash flows generated by financial assets of the securitization, asset-backed financing arrangement, or similar transfer for initial fair value measurement. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 860 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 3 -Subparagraph (c)(1) -Publisher FASB -URI https://asc.fasb.org/1943274/2147481326/860-20-50-3 + Details
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- Definition Weighted average life of securitized assets for initial fair value measurement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 860 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 3 -Subparagraph (c)(2) -Publisher FASB -URI https://asc.fasb.org/1943274/2147481326/860-20-50-3 + 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)(1) -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)(2) -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)(3) -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)(4)(i) -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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