Debt (Detail) - Senior Notes [Member] - INA Senior Notes Due March 2034 [Domain] $ in Billions	Mar. 31, 2024 USD ($)
Debt Instrument [Line Items]
Debt Instrument, Face Amount	$ 1
Debt Instrument, Interest Rate, Stated Percentage	5.00%
Make Whole Premium Additional Percent	0.15%

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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+ Details