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

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.1,2)
-URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688

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- Definition

Total revenue from sale of goods and services rendered during the reporting period, in the normal course of business, reduced by sales returns and allowances, and sales discounts.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.1)
-URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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Geographic and Segment Information (Details) - USD ($) $ in Millions	3 Months Ended								12 Months Ended
	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2018	Mar. 31, 2017	Mar. 31, 2016
Segment Reporting Information [Line Items]
Segment Net Sales	$ 1,002.3	$ 994.2	$ 1,012.1	$ 972.1	$ 902.7	$ 834.4	$ 871.4	$ 799.4	$ 3,980.8	$ 3,407.8	$ 2,173.3
Segment Gross Profit	$ 615.1	$ 607.1	$ 614.1	$ 584.4	$ 532.8	$ 465.3	$ 410.6	$ 348.5	2,420.7	1,757.2	1,205.5
Semiconductor products
Segment Reporting Information [Line Items]
Segment Net Sales									3,876.0	3,316.6	2,084.2
Segment Gross Profit									2,315.9	1,666.0	1,116.4
Technology licensing
Segment Reporting Information [Line Items]
Segment Net Sales									104.8	91.2	89.1
Segment Gross Profit									$ 104.8	$ 91.2	$ 89.1