v3.8.0.1

Share-Based Compensation (Details) - USD ($) $ in Thousands			3 Months Ended		6 Months Ended
		Apr. 04, 2016	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Stock-based compensation expense [Line Items]
Allocated share-based compensation expense			$ 23,610	$ 24,390	$ 46,018	$ 83,969
Income tax benefit			7,846	8,358	15,274	29,246
Net income effect of share-based compensation			15,764	16,032	30,744	54,723
Share-based compensation expense previously capitalized			3,700		7,100
Inventory
Stock-based compensation expense [Line Items]
Income tax benefit			3,100	2,700	5,800	5,500
Share-based compensation expense previously capitalized				4,100		7,800
Cost of Sales
Stock-based compensation expense [Line Items]
Allocated share-based compensation expense			3,699	4,100	7,093	11,997
Research and development
Stock-based compensation expense [Line Items]
Allocated share-based compensation expense			10,587	10,171	20,876	27,688
Selling, General and Administrative
Stock-based compensation expense [Line Items]
Allocated share-based compensation expense			9,324	10,119	18,049	44,284
Atmel Corporation
Stock-based compensation expense [Line Items]
Allocated share-based compensation expense	[1]		6,200		49,400
Share-based compensation expense previously capitalized						4,200
Non cash consideration of certain share-based payment awards		$ 7,500
Accelerated compensation cost					37,200
New Accounting Pronouncement, Early Adoption, Effect | Accounting Standards Update 2016-09, Excess Tax Benefit Component
Stock-based compensation expense [Line Items]
Allocated share-based compensation expense			$ 8,200	$ 5,800	$ 14,100	$ 12,500
[1] During the three and six months ended September 30, 2017, $3.1 million and $5.8 million, respectively, of share-based compensation expense was capitalized to inventory and $3.7 million and $7.1 million, respectively, of previously capitalized share-based compensation expense in inventory was sold. During the three and six months ended September 30, 2016, $2.7 million and $5.5 million, respectively, of share-based compensation expense was capitalized to inventory. The amount of share-based compensation included in cost of sales during the three months ended September 30, 2016 included $4.1 million of previously capitalized share-based compensation expense in inventory that was sold. The amount of share-based compensation included in cost of sales during the six months ended September 30, 2016 included $7.8 million of previously capitalized share-based compensation expense in inventory that was sold and $4.2 million of share-based compensation expense related to the Company's acquisition of Atmel that was not previously capitalized to inventory.

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Business Combination, Consideration Transferred, Share-based Payment Awards

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The amount of share-based compensation expense recognized during the period that was previously capitalized to inventory.

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Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SAB Topic 14.F)
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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
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-Section 50
-Paragraph 1
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-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5047-113901

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The amount of expense, net of income tax, recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

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The total recognized tax benefit related to compensation cost for equity-based payment arrangements recognized in income during the period.

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-Name Accounting Standards Codification
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Additional share-based compensation cost recognized as a result of an occurrence of an event that accelerates its recognition.

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