Debt (Aggregate Maturity Of Debt Obligations) (Detail) $ in Millions	Dec. 31, 2023 USD ($)
Corporate debt [Member]
Debt Instrument [Line Items]
2024	$ 0
2025	45
2026	0
2027	96
2028	112
Thereafter	21
Total	274
Surplus Notes due 2033 [Member]
Debt Instrument [Line Items]
2024	0
2025	0
2026	0
2027	0
2028	0
Thereafter	940
Total	940
Total debt obligations due [Member]
Debt Instrument [Line Items]
2024	0
2025	45
2026	0
2027	96
2028	112
Thereafter	961
Total	$ 1,214

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.

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