v2.4.0.8

Goodwill by Reporting Segment (Details) (USD $) |  |  |  |  |  |  |  | 6 Months Ended |  |  | 6 Months Ended
--- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | ---
Sep. 30, 2014 | Mar. 31, 2014 | Sep. 30, 2014 Supertex Inc. [Member] | Jun. 30, 2014 Supertex Inc. [Member] | Jul. 17, 2014 ISSC Technologies Corporation [Member] | Sep. 30, 2014 Semiconductor products [Member] | Mar. 31, 2014 Semiconductor products [Member] | Sep. 30, 2014 Semiconductor products [Member] Supertex Inc. [Member] | Sep. 30, 2014 Semiconductor products [Member] ISSC Technologies Corporation [Member] | Sep. 30, 2014 Semiconductor products [Member] Other acquisitions | Sep. 30, 2014 Technology licensing [Member] | Mar. 31, 2014 Technology licensing [Member] | Sep. 30, 2014 Technology licensing [Member] Supertex Inc. [Member] | Sep. 30, 2014 Technology licensing [Member] ISSC Technologies Corporation [Member] | Sep. 30, 2014 Technology licensing [Member] Other acquisitions
Goodwill [Roll Forward] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Goodwill, beginning balance | $ 557,965,000 | $ 276,097,000 | $ 132,508,000 | $ 133,713,000 | $ 152,243,000 | $ 538,765,000 | $ 256,897,000 |  |  |  | $ 19,200,000 | $ 19,200,000 |  |  |
Additions due to business combination |  |  |  |  |  |  |  | 132,508,000 | 152,243,000 | 625,000 |  |  | 0 | 0 | 0
Goodwill, Translation Adjustments |  |  |  |  |  |  |  |  | (3,508,000) |  |  |  |  | 0 |
Goodwill, ending balance | $ 557,965,000 | $ 276,097,000 | $ 132,508,000 | $ 133,713,000 | $ 152,243,000 | $ 538,765,000 | $ 256,897,000 |  |  |  | $ 19,200,000 | $ 19,200,000 |  |  |

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- Definition Amount of increase (decrease) from foreign currency translation adjustments of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (f) -URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13816-109267 + Details
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