Variable Interest Entities (Details) $ in Millions	9 Months Ended	12 Months Ended
Sep. 30, 2025 USD ($) entity	Dec. 31, 2024 USD ($) entity
Private-label Securitizations [Line Items]
Number of variable interest entities \| entity	0	0
Fair Value	$ 15,052	$ 10,402
Private label CMOs
Private-label Securitizations [Line Items]
Fair Value	161	163
Recurring \| Private label CMOs
Private-label Securitizations [Line Items]
Fair Value	$ 161	$ 163
Variable Interest Entity, Not Primary Beneficiary
Private-label Securitizations [Line Items]
VIE ownership percentage	5.00%	5.00%

Variable Interest Entity, Number Of Entities

No definition available.

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- Definition

Amount excluding accrued interest, of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 326
-SubTopic 30
-Name Accounting Standards Codification
-Section 45
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479130/326-30-45-1

+ 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 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Subparagraph (b)(3)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481326/860-20-50-3

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- Definition

Percentage of the Variable Interest Entity's (VIE) voting interest owned by (or beneficial interest in) the reporting entity (directly or indirectly).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 810
-SubTopic 10
-Section 50
-Paragraph 5A
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481203/810-10-50-5A

+ Details

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- Details

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- Details

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- Details

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