Note 16 Income Taxes (Effective Tax Rate Reconciliation) (Details)	12 Months Ended
Mar. 31, 2013	Mar. 31, 2012	Mar. 31, 2011
Effective Income Tax Rate, Continuing Operations, Tax Rate Reconciliation [Abstract]
Statutory Federal Income Tax Rate	35.00%	35.00%	35.00%
State Taxes, Net of Federal Tax Benefit	1.00%	2.00%	(1.00%)
Expense (Benefit) of Lower Tax Jurisdictions	0.00%	(5.00%)	(8.00%)
Research and Development Tax Credits	(4.00%)	(1.00%)	(1.00%)
Valuation Allowance	6.00%	(4.00%)	(19.00%)
Permanent Items	4.00%	3.00%	3.00%
Tax Reserves	3.00%	(6.00%)	5.00%
Share-based Compensation	2.00%	1.00%	1.00%
Foreign Income	1.00%	0.00%	0.00%
Effective Tax Provision Rate	48.00%	25.00%	15.00%

No authoritative reference available.

No definition available.

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- Definition

A ratio calculated by dividing the reported amount of income tax expense attributable to continuing operations for the period by GAAP-basis pretax income from continuing operations.

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 08

-Paragraph h

-Subparagraph 2

-Article 4

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-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 109

-Paragraph 47

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 740

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 235

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.4-08.(h)(2))

-URI http://asc.fasb.org/extlink&oid=6881521&loc=d3e23780-122690

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- Definition

The domestic federal statutory tax rate applicable under enacted tax laws to the Company's pretax income from continuing operations for the period. The "statutory" tax rate is the regular tax rate if there are alternative tax systems.

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 109

-Paragraph 47

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 740

-SubTopic 10

-Section 50

-Paragraph 12

-URI http://asc.fasb.org/extlink&oid=6907707&loc=d3e32687-109319

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-Name Accounting Standards Codification

-Topic 740

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-Subparagraph (SAB TOPIC 6.I)

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The portion of the difference between the effective income tax rate and domestic federal statutory income tax rate attributable to changes in the valuation allowance for deferred tax assets.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

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The portion of the difference between the effective income tax rate and domestic federal statutory income tax rate that can be explained by the difference between statutory income tax rates in foreign jurisdictions and the domestic federal statutory income tax rate recorded during the period.

+ References

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The portion of the difference between the effective income tax rate and domestic federal statutory income tax rate attributable to differences in the deductibility or nondeductibility of incentive stock options and other equity-based compensation costs in accordance with generally accepted accounting principles and enacted tax laws.

+ References

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The portion of the difference between the effective income tax rate and domestic federal statutory income tax rate attributable to the repatriation of foreign earnings under enacted tax laws.

+ References

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The portion of the difference between the effective income tax rate and domestic federal statutory income tax rate that can be explained by the state and local income tax expense or benefit, net of the federal tax benefit (expense) thereon, recorded during the period.

+ References

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- Definition

The sum of the differences between the effective income tax rate and domestic federal statutory income tax rate attributable to changes in all income tax contingencies, whether recorded or adjusted, during the period.

+ References

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The portion of the difference between the effective income tax rate and domestic federal statutory income tax rate that can be explained by research tax credits generated or utilized under enacted tax laws during the period.

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