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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
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

Carry amount of assets hedged in fair value hedging relationship

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The carry amount of liabilities in fair value hedging relationship

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[Line Items] for Table shows the carrying amount and associated cumulative basis adjustment related to the application of hedge accounting that is included in the carrying amount of hedged assets and liabilities in fair value hedging relationships.

+ References

No definition available.

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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
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-Name Accounting Standards Codification
-Section 55
-Paragraph 181
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480401/815-10-55-181

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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
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-Section 55
-Paragraph 181
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480401/815-10-55-181

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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

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Amount of cumulative increase (decrease) in fair value of hedged liability 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

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- Definition

Amortized cost of closed portfolio of financial asset used to designate hedging relationship in which hedged item is expected to be outstanding for designated hedged period.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 815
-SubTopic 10
-Name Accounting Standards Codification
-Section 55
-Paragraph 181
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480401/815-10-55-181

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