Income Taxes (Narrative of Carryforwards) (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
Mar. 31, 2013
Federal
Operating Loss Carryforwards	$ 149.3
Operating loss carryforwards, expiration dates	Beginning in 2014 and continuing through 2032
Research and Development Tax Credit Carryforwards	2.4
Research and Development Tax Credit Carryforwards, Expiration Dates	Beginning in 2021 and continuing through 2033
California
Operating Loss Carryforwards	95.4
Operating loss carryforwards, expiration dates	Beginning in 2014 and continuing through 2032
Research and Development Tax Credit Carryforwards	$ 3.7
Research and Development Tax Credit Carryforwards, Expiration Dates	California credits will carry forward indefinitely

Amount of operating loss carryforward, before tax effects, available to reduce future taxable income under enacted tax laws.

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- Definition

The expiration date of each operating loss carryforward included in total operating loss carryforwards, or the applicable range of such expiration dates.

+ References

No definition available.

+ Details

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- Definition

The amount of the tax credit carryforward, before tax effects, available to reduce future taxable income under enacted tax laws.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 740

-SubTopic 10

-Section 50

-Paragraph 3

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=6907707&loc=d3e32559-109319

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Carryforwards

-URI http://asc.fasb.org/extlink&oid=6506874

+ Details

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- Definition

State the expiration dates of the tax credit carryforward.

+ References

No definition available.

+ Details

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