Segment Information - Net Sales and Gross Profit (Details) - USD ($) $ in Millions	3 Months Ended
	Jun. 30, 2021	Jun. 30, 2020
Segment reporting information [Line Items]
Net Sales	$ 1,569.4	$ 1,309.7
Gross Profit	1,007.6	798.3
Semiconductor products
Segment reporting information [Line Items]
Net Sales	1,542.0	1,287.8
Gross Profit	980.2	776.4
Technology licensing
Segment reporting information [Line Items]
Net Sales	27.4	21.9
Gross Profit	$ 27.4	$ 21.9