Income Taxes (Details) - USD ($) $ in Millions	3 Months Ended
Income Taxes (Details) - USD ($) $ in Millions	Jun. 30, 2025	Jun. 30, 2024
Income Tax Disclosure [Abstract]
Income tax benefit (expense)	$ (16.0)	$ (21.0)

Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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+ Details

ARM HOLDINGS PLC /UK 6-K