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Derivative Instruments and Hedging Activities - Hedged Items in Fair Value Hedging Relationship (Details) - USD ($) $ in Millions | Sep. 30, 2025 | Dec. 31, 2024
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Hedged Items In Fair Value Hedging Relationship [Line Items] |  |
Total Assets | $ (36) | $ (16)
Discontinued Hedging Relationships, Assets | 3,800 | 3,400
Designated hedged items | 2,600 | 2,100
Investment securities available for sale |  |
Hedged Items In Fair Value Hedging Relationship [Line Items] |  |
Carrying Amount Assets | 8,445 | 8,312
Total Assets | (107) | 38
Discontinued Hedging Relationships, Assets | 46 | 78
Interest-bearing deposits |  |
Hedged Items In Fair Value Hedging Relationship [Line Items] |  |
Carrying Amount Liabilities | (7,181) | (10,331)
Total Liabilities | 30 | 160
Discontinued Hedging Relationships, Liabilities | 0 | 0
Securitized debt obligations |  |
Hedged Items In Fair Value Hedging Relationship [Line Items] |  |
Carrying Amount Liabilities | (10,732) | (11,011)
Total Liabilities | 139 | 276
Discontinued Hedging Relationships, Liabilities | 0 | 0
Senior and subordinated notes |  |
Hedged Items In Fair Value Hedging Relationship [Line Items] |  |
Carrying Amount Liabilities | (34,646) | (30,696)
Total Liabilities | 278 | 1,069
Discontinued Hedging Relationships, Liabilities | $ (140) | $ (225)

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- Definition Amount of cumulative increase (decrease) in fair value of hedged asset in fair value hedge, attributable to hedged risk, remaining after discontinued hedge. Excludes cumulative basis adjustment related to foreign exchange risk. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 815 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 4EE -Subparagraph (d) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480434/815-10-50-4EE Reference 2: http://www.xbrl.org/2003/role/exampleRef -Topic 815 -SubTopic 10 -Name Accounting Standards Codification -Section 55 -Paragraph 181 -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480401/815-10-55-181 + Details
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- Definition Amount of cumulative increase (decrease) in fair value of hedged asset in fair value hedge, attributable to hedged risk. Excludes cumulative basis adjustment related to foreign exchange risk. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 815 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 4EE -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480434/815-10-50-4EE Reference 2: http://www.xbrl.org/2003/role/exampleRef -Topic 815 -SubTopic 10 -Name Accounting Standards Codification -Section 55 -Paragraph 181 -Publisher FASB -URI https://asc.fasb.org/1943274/2147480401/815-10-55-181 + Details
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- Definition Amount of cumulative increase (decrease) in fair value of hedged liability in fair value hedge, attributable to hedged risk, remaining after discontinued hedge. Excludes cumulative basis adjustment related to foreign exchange risk. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 815 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 4EE -Subparagraph (d) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480434/815-10-50-4EE + Details
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