Debt (Detail) - Senior Notes [Member] - INA CHF Bond Due 2032 SFr in Millions, $ in Millions	Mar. 17, 2026 CHF (SFr)	Mar. 17, 2026 USD ($)
Debt Instrument [Line Items]
Debt Instrument, Face Amount	SFr 200	$ 254
Debt Instrument, Interest Rate, Stated Percentage	1.02%	1.02%

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