v2.4.0.8

Intangible Assets, by Major Class (Details) (USD $) | 3 Months Ended | 6 Months Ended |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 3 Months Ended | 0 Months Ended | 3 Months Ended | 6 Months Ended | 3 Months Ended | 6 Months Ended
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Sep. 30, 2014 | Sep. 30, 2013 | Sep. 30, 2014 | Sep. 30, 2013 | Mar. 31, 2014 | Sep. 30, 2014 Core/developed technology | Mar. 31, 2014 Core/developed technology | Sep. 30, 2014 Customer Relationships [Member] | Mar. 31, 2014 Customer Relationships [Member] | Sep. 30, 2014 Trademarks and trade names [Member] | Mar. 31, 2014 Trademarks and trade names [Member] | Sep. 30, 2014 Backlog [Member] | Mar. 31, 2014 Backlog [Member] | Sep. 30, 2014 In-process technology [Member] | Mar. 31, 2014 In-process technology [Member] | Sep. 30, 2014 Distribution rights [Member] | Mar. 31, 2014 Distribution rights [Member] | Sep. 30, 2014 Covenants not to compete [Member] | Mar. 31, 2014 Covenants not to compete [Member] | Sep. 30, 2014 Minimum [Member] | Sep. 30, 2014 Maximum [Member] | Apr. 01, 2014 Supertex Inc. [Member] | Apr. 01, 2014 Supertex Inc. [Member] Core/developed technology | Apr. 01, 2014 Supertex Inc. [Member] Backlog [Member] | Sep. 30, 2014 Cost of Sales [Member] | Sep. 30, 2013 Cost of Sales [Member] | Sep. 30, 2014 Cost of Sales [Member] | Sep. 30, 2013 Cost of Sales [Member] | Sep. 30, 2014 Operating Expense [Member] | Sep. 30, 2013 Operating Expense [Member] | Sep. 30, 2014 Operating Expense [Member] | Sep. 30, 2013 Operating Expense [Member]
Finite-Lived Intangible Assets, Net [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Gross Amount | $ 946,930,000 |  | $ 946,930,000 |  | $ 709,190,000 | $ 559,828,000 | $ 402,669,000 | $ 263,805,000 | $ 195,800,000 | $ 15,730,000 | $ 15,730,000 | $ 26,302,000 | $ 24,610,000 | $ 75,280,000 | $ 64,396,000 | $ 5,585,000 | $ 5,585,000 | $ 400,000 | $ 400,000 |  |  |  |  |  |  |  |  |  |  |  |  |
Accumulated Amortization | (347,905,000) |  | (347,905,000) |  | (263,691,000) | (161,145,000) | (117,222,000) | (147,489,000) | (109,170,000) | (8,323,000) | (7,118,000) | (25,331,000) | (24,610,000) | 0 | 0 | (5,217,000) | (5,171,000) | (400,000) | (400,000) |  |  |  |  |  |  |  |  |  |  |  |  |
Net Amount | 599,025,000 |  | 599,025,000 |  | 445,499,000 | 398,683,000 | 285,447,000 | 116,316,000 | 86,630,000 | 7,407,000 | 8,612,000 | 971,000 | 0 | 75,280,000 | 64,396,000 | 368,000 | 414,000 | 0 | 0 |  |  |  |  |  |  |  |  |  |  |  |  |
In-process technology reaching technological feasibility and reclassified |  |  | 24,400,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Purchased Intangible Assets |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 89,600,000 | 68,900,000 | 1,100,000 |  |  |  |  |  |  |  |
Useful Life |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 1 year | 15 years |  | 10 years | 1 year |  |  |  |  |  |  |  |
Minimum expected useful life of finite lived intangible assets (in years) |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 1 year | 15 years |  | 10 years | 1 year |  |  |  |  |  |  |  |
Amortization of Intangible Assets | 46,500,000 | 25,100,000 | 84,200,000 | 54,000,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 1,000,000 | 1,300,000 | 2,000,000 | 2,500,000 | 45,500,000 | 23,800,000 | 82,200,000 | 51,500,000
Impairment of Intangible Assets | 150,000 |  | 556,000 | 350,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Future Amortization Expense, Remainder of Fiscal Year | 99,063,000 |  | 99,063,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Future Amortization Expense, Year Two | 150,298,000 |  | 150,298,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Future Amortization Expense, Year Three | 92,227,000 |  | 92,227,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Future Amortization Expense, Year Four | 73,926,000 |  | 73,926,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Future Amortization Expense, Year Five | $ 65,650,000 |  | $ 65,650,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |

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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 230 -SubTopic 10 -Section 45 -Paragraph 28 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3602-108585 Reference 2: 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 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 30 -Section 50 -Paragraph 2 -Subparagraph (a)(2) -URI http://asc.fasb.org/extlink&oid=26713463&loc=d3e16323-109275 + Details
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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=26713463&loc=d3e16323-109275 + Details
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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 next 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=26713463&loc=d3e16323-109275 + Details
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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. + Details
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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) -URI http://asc.fasb.org/extlink&oid=26713463&loc=d3e16323-109275 + Details
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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 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) -URI http://asc.fasb.org/extlink&oid=26713463&loc=d3e16323-109275 + Details
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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 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) -URI http://asc.fasb.org/extlink&oid=26713463&loc=d3e16323-109275 + Details
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- Definition Amount before 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=26713463&loc=d3e16323-109275 + Details
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- Definition Amount after 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=26713463&loc=d3e16323-109275 + Details
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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. + Details
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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 -Section 50 -Paragraph 3 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=26713463&loc=d3e16373-109275 + Details
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