Segment Information - Net Sales and Gross Profit (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2023	Dec. 31, 2022
Segment reporting information [Line Items]
Net Sales	$ 1,765.7	$ 2,169.2	$ 6,308.6	$ 6,206.0
Gross Profit	1,120.0	1,470.8	4,205.8	4,178.6
Semiconductor products
Segment reporting information [Line Items]
Net Sales	1,741.5	2,124.8	6,224.0	6,078.7
Gross Profit	1,095.8	1,426.4	4,121.2	4,051.3
Technology licensing
Segment reporting information [Line Items]
Net Sales	24.2	44.4	84.6	127.3
Gross Profit	$ 24.2	$ 44.4	$ 84.6	$ 127.3