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Fair Value of Financial Instruments (Aggregate Fair Value And Remaining Contractual Principal Balance Outstanding On Fair Value Option) (Detail) - USD ($) $ in Millions | Dec. 31, 2023 | Dec. 31, 2022
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Residential Mortgage Loans [Member] | Loans Receivable [Member] |  |
Schedule Of Fair Value Of Separate Accounts By Major Category Of Investment [Line Items] |  |
Loans receivable and other instruments, contractual outstanding principal | $ 18 | $ 39
Loans receivable and other instruments, 90 days or more past due, contractual outstanding principal | 58 | 149
Loans receivable and other instruments, fair value | 18 | 39
Loans receivable and other instruments, 90 days or more past due, fair value | 17 | 39
Loans receivable and other instruments, difference | 0 | 0
Loans receivable and other instruments, 90 days or more past due, difference | 41 | 110
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 and other instruments, contractual outstanding principal | 76 | 188
Loans receivable and other instruments, fair value | 35 | 78
Loans receivable and other instruments, difference | 41 | 110
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 | 328 | 780
Long-term debt instruments, fair value | 78 | 172
Long-term debt instruments, difference | 250 | 608
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 | 55 | 53
Long-term debt instruments, fair value | 40 | 41
Long-term debt instruments, difference | $ 15 | $ 12

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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 + Details
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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 -Topic 825 -SubTopic 10 -Section 50 -Paragraph 28 -Subparagraph (e)(1) -Publisher FASB -URI https://asc.fasb.org//1943274/2147482907/825-10-50-28 + Details
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