Certain Financial Statement Information Purchased Intangibles (Details) (USD $) In Thousands, unless otherwise specified	9 Months Ended	12 Months Ended
Dec. 31, 2014	Mar. 31, 2014
Schedule of Purchased Intangible assets
Gross Assets	$ 493,636	$ 493,636
Accumulated Amortization and Impairments	(493,636)	(493,531)
Intangible Assets, Net (Excluding Goodwill)	0	105
Developed technology/in-process research and development [Member]
Schedule of Purchased Intangible assets
Gross Assets	425,000	425,000
Accumulated Amortization and Impairments	(425,000)	(425,000)
Intangible Assets, Net (Excluding Goodwill)	0	0
Weighted average remaining useful life	0 years	0 years
Customer relationships [Member]
Schedule of Purchased Intangible assets
Gross Assets	6,330	6,330
Accumulated Amortization and Impairments	(6,330)	(6,225)
Intangible Assets, Net (Excluding Goodwill)	0	105
Weighted average remaining useful life	0 years	4 months 24 days
Patents/core technology rights/tradename [Member]
Schedule of Purchased Intangible assets
Gross Assets	62,306	62,306
Accumulated Amortization and Impairments	(62,306)	(62,306)
Intangible Assets, Net (Excluding Goodwill)	$ 0	$ 0
Weighted average remaining useful life	0 years	0 years

Acquired finite-lived intangible asset, accumulated amortization and impairments.

No definition available.

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- Definition

Acquired finite-lived intangible asset, gross.

+ References

No definition available.

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- Definition

Weighted average amortization period of finite-lived intangible assets acquired either individually or as part of a group of assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 30

-Section 50

-Paragraph 1

-Subparagraph (a)(3)

-URI http://asc.fasb.org/extlink&oid=26713463&loc=d3e16265-109275

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- Definition

Sum of the carrying amounts of all intangible assets, excluding goodwill, as of the balance sheet date, net of accumulated amortization and impairment charges.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 30

-Section 45

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6388964&loc=d3e16212-109274

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 30

-Section 50

-Paragraph 2

-Subparagraph ((a)(1),(b))

-URI http://asc.fasb.org/extlink&oid=26713463&loc=d3e16323-109275

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