Fair Value of Financial Instruments (Aggregate Fair Value And Remaining Contractual Principal Balance Outstanding On Fair Value Option) (Detail) - USD ($) $ in Millions	Dec. 31, 2024	Dec. 31, 2023
Residential Mortgage Loans [Member] \| Loans Receivable [Member]
Schedule Of Fair Value Of Separate Accounts By Major Category Of Investment [Line Items]
Loans receivable, contractual outstanding principal	$ 12	$ 18
Loans receivable, 90 days or more past due, contractual outstanding principal	48	58
Loans receivable, fair value	12	18
Loans receivable, 90 days or more past due, fair value	16	17
Loans receivable, difference	0	0
Loans receivable, 90 days or more past due, difference	32	41
Corporate Loans - Current [Member] \| Loans Receivable [Member]
Schedule Of Fair Value Of Separate Accounts By Major Category Of Investment [Line Items]
Loans receivable, contractual outstanding principal	16	0
Loans receivable, fair value	15	0
Loans receivable, difference	1	0
Total Loans Receivable and Other Instruments [Member] \| Loans Receivable [Member]
Schedule Of Fair Value Of Separate Accounts By Major Category Of Investment [Line Items]
Loans receivable, contractual outstanding principal	76	76
Loans receivable, fair value	43	35
Loans receivable, difference	33	41
Variable Interest Entity Notes [Member]
Schedule Of Fair Value Of Separate Accounts By Major Category Of Investment [Line Items]
Long-term debt instruments, contractual outstanding principal	45	328
Long-term debt instruments, fair value	31	78
Long-term debt instruments, difference	14	250
Medium Term Notes [Member]
Schedule Of Fair Value Of Separate Accounts By Major Category Of Investment [Line Items]
Long-term debt instruments, contractual outstanding principal	52	55
Long-term debt instruments, fair value	35	40
Long-term debt instruments, difference	$ 17	$ 15

Fair Value Option Aggregate Fair Value Loans Receivable

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- Definition

Fair Value Option Aggregate Fair Value Long Term Debt Instruments

+ References

No definition available.

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- Definition

Fair Value Option Contractual Outstanding Principal Loans Receivable

+ References

No definition available.

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- Definition

Fair Value Option Contractual Outstanding Principal Loans Receivable 90 Days or More Past Due

+ References

No definition available.

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- Definition

Fair Value Option Contractual Outstanding Principal Long-Term Debt Instruments

+ References

No definition available.

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- Definition

This item represents the difference between the aggregate fair value and the aggregate unpaid principal balance of loans and long-term receivables (other than securities categorized as trading, available-for-sale or held-to-maturity) that have contractual principal amounts and for which the fair value option has been elected.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 28
-Subparagraph (d)(1)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482907/825-10-50-28

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- Definition

This item represents the difference between the aggregate fair value and the aggregate unpaid principal balance of long-term debt instruments that have contractual principal amounts and for which the fair value option has been elected.

+ References

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-SubTopic 10
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- Definition

This item represents the aggregate fair value of loans held as assets that are 90 days or more past due for which the fair value option has been elected.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
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- Definition

For loans held as assets for which the fair value option has been elected, this item represents the difference between the aggregate fair value and the aggregate unpaid principal balance of those loans that are 90 days or more past due.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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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/exampleRef
-Topic 944
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