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v3.23.3

Variable Interest Entities (Summary of Nonconsolidated VIEs Assets and Liabilities) (Detail) - USD ($) $ in Millions | Sep. 30, 2023 | Dec. 31, 2022
--- | --- | ---
Variable Interest Entity [Line Items] |  |
Maximum Exposure to Loss | $ 1,607 | $ 1,840
Carrying Value of VIE Assets | 2,990 | 3,375
Carrying Value of VIE Liabilities | 4,218 | 4,251
Investments [Member] |  |
Variable Interest Entity [Line Items] |  |
Carrying Value of VIE Assets | 18 | 75
Premiums Receivable [Member] |  |
Variable Interest Entity [Line Items] |  |
Carrying Value of VIE Assets | 11 | 14
Insurance Loss Recoverable [Member] |  |
Variable Interest Entity [Line Items] |  |
Carrying Value of VIE Assets | 27 | 28
Unearned Premium Revenue [Member] |  |
Variable Interest Entity [Line Items] |  |
Carrying Value of VIE Liabilities | 10 | 12
Loss And Loss Adjustment Expense Reserves [Member] |  |
Variable Interest Entity [Line Items] |  |
Carrying Value of VIE Liabilities | 222 | 282
Corporate Asset Backed [Member] | Loss And Loss Adjustment Expense Reserves [Member] |  |
Variable Interest Entity [Line Items] |  |
Carrying Value of VIE Liabilities |  | 0
Global Structured Finance [Member] |  |
Variable Interest Entity [Line Items] |  |
Maximum Exposure to Loss | 1,391 | 1,610
Global Structured Finance [Member] | Investments [Member] |  |
Variable Interest Entity [Line Items] |  |
Carrying Value of VIE Assets | 18 | 75
Global Structured Finance [Member] | Premiums Receivable [Member] |  |
Variable Interest Entity [Line Items] |  |
Carrying Value of VIE Assets | 7 | 9
Global Structured Finance [Member] | Insurance Loss Recoverable [Member] |  |
Variable Interest Entity [Line Items] |  |
Carrying Value of VIE Assets | 27 | 28
Global Structured Finance [Member] | Unearned Premium Revenue [Member] |  |
Variable Interest Entity [Line Items] |  |
Carrying Value of VIE Liabilities | 6 | 8
Global Structured Finance [Member] | Loss And Loss Adjustment Expense Reserves [Member] |  |
Variable Interest Entity [Line Items] |  |
Carrying Value of VIE Liabilities | 222 | 282
Global Structured Finance [Member] | Residential Mortgage Backed Securities [Member] |  |
Variable Interest Entity [Line Items] |  |
Maximum Exposure to Loss | 848 | 996
Global Structured Finance [Member] | Residential Mortgage Backed Securities [Member] | Investments [Member] |  |
Variable Interest Entity [Line Items] |  |
Carrying Value of VIE Assets | 18 | 75
Global Structured Finance [Member] | Residential Mortgage Backed Securities [Member] | Premiums Receivable [Member] |  |
Variable Interest Entity [Line Items] |  |
Carrying Value of VIE Assets | 5 | 6
Global Structured Finance [Member] | Residential Mortgage Backed Securities [Member] | Insurance Loss Recoverable [Member] |  |
Variable Interest Entity [Line Items] |  |
Carrying Value of VIE Assets | 19 | 21
Global Structured Finance [Member] | Residential Mortgage Backed Securities [Member] | Unearned Premium Revenue [Member] |  |
Variable Interest Entity [Line Items] |  |
Carrying Value of VIE Liabilities | 3 | 4
Global Structured Finance [Member] | Residential Mortgage Backed Securities [Member] | Loss And Loss Adjustment Expense Reserves [Member] |  |
Variable Interest Entity [Line Items] |  |
Carrying Value of VIE Liabilities | 219 | 277
Global Structured Finance [Member] | Consumer Asset Backed [Member] |  |
Variable Interest Entity [Line Items] |  |
Maximum Exposure to Loss | 130 | 164
Global Structured Finance [Member] | Consumer Asset Backed [Member] | Investments [Member] |  |
Variable Interest Entity [Line Items] |  |
Carrying Value of VIE Assets | 0 | 0
Global Structured Finance [Member] | Consumer Asset Backed [Member] | Premiums Receivable [Member] |  |
Variable Interest Entity [Line Items] |  |
Carrying Value of VIE Assets | 0 | 0
Global Structured Finance [Member] | Consumer Asset Backed [Member] | Insurance Loss Recoverable [Member] |  |
Variable Interest Entity [Line Items] |  |
Carrying Value of VIE Assets | 1 | 0
Global Structured Finance [Member] | Consumer Asset Backed [Member] | Unearned Premium Revenue [Member] |  |
Variable Interest Entity [Line Items] |  |
Carrying Value of VIE Liabilities | 0 | 1
Global Structured Finance [Member] | Consumer Asset Backed [Member] | Loss And Loss Adjustment Expense Reserves [Member] |  |
Variable Interest Entity [Line Items] |  |
Carrying Value of VIE Liabilities | 3 | 5
Global Structured Finance [Member] | Corporate Asset Backed [Member] |  |
Variable Interest Entity [Line Items] |  |
Maximum Exposure to Loss | 413 | 450
Global Structured Finance [Member] | Corporate Asset Backed [Member] | Investments [Member] |  |
Variable Interest Entity [Line Items] |  |
Carrying Value of VIE Assets | 0 | 0
Global Structured Finance [Member] | Corporate Asset Backed [Member] | Premiums Receivable [Member] |  |
Variable Interest Entity [Line Items] |  |
Carrying Value of VIE Assets | 2 | 3
Global Structured Finance [Member] | Corporate Asset Backed [Member] | Insurance Loss Recoverable [Member] |  |
Variable Interest Entity [Line Items] |  |
Carrying Value of VIE Assets | 7 | 7
Global Structured Finance [Member] | Corporate Asset Backed [Member] | Unearned Premium Revenue [Member] |  |
Variable Interest Entity [Line Items] |  |
Carrying Value of VIE Liabilities | 3 | 3
Global Structured Finance [Member] | Corporate Asset Backed [Member] | Loss And Loss Adjustment Expense Reserves [Member] |  |
Variable Interest Entity [Line Items] |  |
Carrying Value of VIE Liabilities | 0 |
Global Public Finance [Member] |  |
Variable Interest Entity [Line Items] |  |
Maximum Exposure to Loss | 216 | 230
Global Public Finance [Member] | Investments [Member] |  |
Variable Interest Entity [Line Items] |  |
Carrying Value of VIE Assets | 0 | 0
Global Public Finance [Member] | Premiums Receivable [Member] |  |
Variable Interest Entity [Line Items] |  |
Carrying Value of VIE Assets | 4 | 5
Global Public Finance [Member] | Insurance Loss Recoverable [Member] |  |
Variable Interest Entity [Line Items] |  |
Carrying Value of VIE Assets | 0 | 0
Global Public Finance [Member] | Unearned Premium Revenue [Member] |  |
Variable Interest Entity [Line Items] |  |
Carrying Value of VIE Liabilities | 4 | 4
Global Public Finance [Member] | Loss And Loss Adjustment Expense Reserves [Member] |  |
Variable Interest Entity [Line Items] |  |
Carrying Value of VIE Liabilities | $ 0 | $ 0

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