Segment Information (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Segment reporting information [Line Items]
Net Sales	$ 1,337.8	$ 1,432.5	$ 2,660.4	$ 2,644.9
Gross Profit	827.5	689.3	1,642.7	1,331.3
Semiconductor products
Segment reporting information [Line Items]
Net Sales	1,314.6	1,394.3	2,618.6	2,580.0
Gross Profit	804.3	651.1	1,600.9	1,266.4
Technology licensing
Segment reporting information [Line Items]
Net Sales	23.2	38.2	41.8	64.9
Gross Profit	$ 23.2	$ 38.2	$ 41.8	$ 64.9

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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