The amount of in-process technology reaching technological feasibility and reclassified as developed technology

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- Definition

The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=6388964&loc=d3e16225-109274

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
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-Section 45
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-Subparagraph (b)
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-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 50
-Paragraph 2
-Subparagraph (a)(2)
-URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16323-109275

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- Definition

Useful life of finite-lived intangible assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

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- Definition

Accumulated amount of amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 50
-Paragraph 2
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16323-109275

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- Definition

Amount of amortization expense for assets, excluding financial assets and goodwill, lacking physical substance with a finite life expected to be recognized in the remainder of the fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

No definition available.

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- Definition

Amount of amortization expense for assets, excluding financial assets and goodwill, lacking physical substance with a finite life expected to be recognized during the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 50
-Paragraph 2
-Subparagraph (a)(3)
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Amount of amortization expense for assets, excluding financial assets and goodwill, lacking physical substance with a finite life expected to be recognized during the fourth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 50
-Paragraph 2
-Subparagraph (a)(3)
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Amount of amortization expense for assets, excluding financial assets and goodwill, lacking physical substance with a finite life expected to be recognized during the third fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 50
-Paragraph 2
-Subparagraph (a)(3)
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- Definition

Amount of amortization expense for assets, excluding financial assets and goodwill, lacking physical substance with a finite life expected to be recognized during the second fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 50
-Paragraph 2
-Subparagraph (a)(3)
-URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16323-109275

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- References

No definition available.

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- Definition

Amount before amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

+ References

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Amount after amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

+ References

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- Definition

Amount of increase in assets, excluding financial assets, lacking physical substance with a definite life, from an acquisition.

+ References

No definition available.

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- Definition

The amount of impairment loss recognized in the period resulting from the write-down of the carrying amount of a finite-lived intangible asset to fair value.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
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-Paragraph 3
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Intangible Assets, by Major Class (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	Mar. 31, 2017
Finite-Lived Intangible Assets, Net [Abstract]
Gross Amount		$ 2,704,884		$ 2,704,884		$ 2,706,512
Accumulated Amortization		(799,154)		(799,154)		(558,420)
Net Amount		1,905,730		1,905,730		2,148,092
In-process technology reaching technological feasibility and reclassified				8,900
Amortization of Intangible Assets		122,700	$ 82,800	245,500	$ 165,300
Impairment of Intangible Assets				215	1,984
Projected Amortization Expense
2018		244,942		244,942
2019		361,769		361,769
2020		313,684		313,684
2021		257,444		257,444
2022		190,439		190,439
Core and developed technology
Finite-Lived Intangible Assets, Net [Abstract]
Gross Amount		1,939,833		1,939,833		1,932,329
Accumulated Amortization		(532,821)		(532,821)		(419,468)
Net Amount		1,407,012		1,407,012		1,512,861
Customer-related
Finite-Lived Intangible Assets, Net [Abstract]
Gross Amount		716,945		716,945		716,945
Accumulated Amortization		(249,773)		(249,773)		(123,616)
Net Amount		467,172		467,172		593,329
Trademarks and trade names
Finite-Lived Intangible Assets, Net [Abstract]
Gross Amount		11,700		11,700		11,700
Accumulated Amortization		(10,668)		(10,668)		(9,636)
Net Amount		1,032		1,032		2,064
In-process technology
Finite-Lived Intangible Assets, Net [Abstract]
Gross Amount		29,379		29,379		38,511
Accumulated Amortization		0		0		0
Net Amount		29,379		29,379		38,511
Distribution rights
Finite-Lived Intangible Assets, Net [Abstract]
Gross Amount		5,578		5,578		5,578
Accumulated Amortization		(5,368)		(5,368)		(5,346)
Net Amount		210		210		232
Other
Finite-Lived Intangible Assets, Net [Abstract]
Gross Amount		1,449		1,449		1,449
Accumulated Amortization		(524)		(524)		(354)
Net Amount		925		$ 925		$ 1,095
Minimum
Finite-Lived Intangible Assets, Net [Abstract]
Useful life				1 year
Maximum
Finite-Lived Intangible Assets, Net [Abstract]
Useful life				15 years
Atmel Corporation
Finite-Lived Intangible Assets, Net [Abstract]
Useful life	9 years
Purchased intangible assets	$ 1,888,392
Atmel Corporation \| Core and developed technology
Finite-Lived Intangible Assets, Net [Abstract]
Useful life	11 years
Purchased intangible assets	$ 1,074,987
Atmel Corporation \| In-process technology
Finite-Lived Intangible Assets, Net [Abstract]
Purchased intangible assets	$ 140,700
Atmel Corporation \| Other
Finite-Lived Intangible Assets, Net [Abstract]
Useful life	5 years
Purchased intangible assets	$ 1,805
Cost of Sales
Finite-Lived Intangible Assets, Net [Abstract]
Amortization of Intangible Assets		1,900	1,000	$ 3,900	1,900
Operating Expense
Finite-Lived Intangible Assets, Net [Abstract]
Amortization of Intangible Assets		$ 120,800	$ 81,800	$ 241,600	$ 163,400