Note 12 Employee Equity Incentive Plans (Narratives) (Details) (USD $) In Millions, except Share data, unless otherwise specified	3 Months Ended
Jun. 30, 2013
Plan 2013 Approved on May 17, 2013 [Member]
Employee Equity Incentive Plans [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized	2,000,000
Plan 2009 Approved on September 10, 2009 [Member]
Employee Equity Incentive Plans [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized	900,000
Plan 2011 Approved on September 16, 2011 [Member]
Employee Equity Incentive Plans [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized	600,000
Stock Options of Plans 2009 and 2011 [Member]
Employee Equity Incentive Plans [Line Items]
Per Share Option Exercise Price as a Percentage of Fair Market Value on Grant Date Not Less Than	100.00%
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period	4 years 0 months 0 days
Share-based Compensation Arrangement by Share-based Payment Award, Expiration from Award Date	ten years from the date of grant
Stock Appreciation Rights of Plans 2009 and 2011 [Member]
Employee Equity Incentive Plans [Line Items]
Per Share Option Exercise Price as a Percentage of Fair Market Value on Grant Date Not Less Than	100.00%
Share-based Compensation Arrangement by Share-based Payment Award, Expiration from Award Date	no later than 10 years from the grant date
Zilog 2004 Plan [Member]
Employee Equity Incentive Plans [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award Number of Shares Assumed	652,963
Employee Stock Purchase Plan 1999 Approved in May 1999 [Member]
Employee Equity Incentive Plans [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized	500,000
ESPP Discounted Purchase Price Percentage	85.00%
ESPP Purchase Period	semi-annual
Share-based Compensation Arrangement by Share-based Payment Award, Maximum Employee Subscription Rate	15.00%
Stock Issued During Period, Shares, Employee Stock Purchase Plans	55,231
Number of Employee Stock Purchase Plan Shares Available for Future Issuance	131,124
Subsequent ESPP Purchase Approval on July 31, 2007 [Member]
Employee Equity Incentive Plans [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized	350,000
Subsequent ESPP Purchase Approval on July 9, 2010 [Member]
Employee Equity Incentive Plans [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized	350,000
Equity Incentive Plans Total [Member]
Employee Equity Incentive Plans [Line Items]
Unrecognized Compensation Cost of Stock Option Granted	$ 5.4
Weighted Average Period of the Unrecognized Compensation Cost to be Recognized	2 years 6 months 0 days

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The discounted percentage of the fair market value of the Company's common stock in Employee Stock Purchase Plan.

+ References

No definition available.

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- Definition

Purchase period of employee stock purchase plan.

+ References

No definition available.

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- Definition

Number of shares available for future issuance in the employee stock purchase plan.

+ References

No definition available.

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- Definition

The percentage of fair market value per share on the date of grant used to establish the floor exercise price for incentive option.

+ References

No definition available.

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- Definition

The equity-based award expiration date.

+ References

No definition available.

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- Definition

The number of shares available for grants under the award plans assumed through business combination at the time of the assumption of the plans.

+ References

No definition available.

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- Definition

As of the balance sheet date, the aggregate unrecognized cost of equity-based awards made to employees under equity-based compensation awards that have yet to vest.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (i)

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- Definition

Weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

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- Definition

Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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- Definition

The highest percentage of annual salary that an employee is permitted to utilize with respect to the plan.

+ References

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

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Reference 3: http://www.xbrl.org/2003/role/presentationRef

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- Definition

The maximum number of shares (or other type of equity) originally approved (usually by shareholders and board of directors), net of any subsequent amendments and adjustments, for awards under the equity-based compensation plan. As stock or unit options and equity instruments other than options are awarded to participants, the shares or units remain authorized and become reserved for issuance under outstanding awards (not necessarily vested).

+ References

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-Paragraph A240

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- Definition

Number of shares issued during the period as a result of an employee stock purchase plan.

+ References

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

-Publisher AICPA

-Name Accounting Principles Board Opinion (APB)

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