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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 | Mar. 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 | $ 42 | $ 39
Loans receivable and other instruments, 90 days or more past due, contractual outstanding principal | 161 | 149
Loans receivable and other instruments, fair value | 42 | 39
Loans receivable and other instruments, 90 days or more past due, fair value | 41 | 39
Loans receivable and other instruments, difference | 0 | 0
Loans receivable and other instruments, 90 days or more past due, difference | 120 | 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 | 203 | 188
Loans receivable and other instruments, fair value | 83 | 78
Loans receivable and other instruments, difference | 120 | 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 | 610 | 780
Long-term debt instruments, fair value | 154 | 172
Long-term debt instruments, difference | 456 | 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 | 54 | 53
Long-term debt instruments, fair value | 42 | 41
Long-term debt instruments, difference | $ 12 | $ 12

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- Definition Fair Value Option Contractual Outstanding Principal Loans Receivable + References No definition available. + Details
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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 -Publisher FASB -Name Accounting Standards Codification -Topic 825 -SubTopic 10 -Section 50 -Paragraph 28 -Subparagraph (d)(1) -URI https://asc.fasb.org/extlink&oid=123596393&loc=d3e14064-108612 + Details
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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 Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 825 -SubTopic 10 -Section 50 -Paragraph 28 -Subparagraph (d)(2) -URI https://asc.fasb.org/extlink&oid=123596393&loc=d3e14064-108612 + 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 -Publisher FASB -Name Accounting Standards Codification -Topic 825 -SubTopic 10 -Section 50 -Paragraph 28 -Subparagraph (e)(1) -URI https://asc.fasb.org/extlink&oid=123596393&loc=d3e14064-108612 + Details
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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 -Publisher FASB -Name Accounting Standards Codification -Topic 825 -SubTopic 10 -Section 50 -Paragraph 28 -Subparagraph (e)(3) -URI https://asc.fasb.org/extlink&oid=123596393&loc=d3e14064-108612 + Details
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