Segment Information (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2019	Dec. 31, 2018
Segment reporting information [Line Items]
Net Sales	$ 1,287.4	$ 1,374.7	$ 3,947.8	$ 4,019.7
Gross Profit	785.5	779.6	2,428.2	2,110.9
Semiconductor products
Segment reporting information [Line Items]
Net Sales	1,257.0	1,331.3	3,875.6	3,911.4
Gross Profit	755.1	736.2	2,356.0	2,002.6
Technology licensing
Segment reporting information [Line Items]
Net Sales	30.4	43.4	72.2	108.3
Gross Profit	$ 30.4	$ 43.4	$ 72.2	$ 108.3

Aggregate revenue less cost of goods and services sold or operating expenses directly attributable to the revenue generation activity.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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