Note 11 Employee Equity Incentive Plans (Narratives) (Details) (USD $) In Millions, except Share data, unless otherwise specified	3 Months Ended	6 Months Ended
Sep. 30, 2012	Sep. 30, 2012
Plan 2009 [Member]
Employee Equity Incentive Plans [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized	900,000	900,000
Plan 2011 [Member]
Employee Equity Incentive Plans [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized	600,000	600,000
Stock Options of Plans 2009 and 2011 [Member]
Employee Equity Incentive Plans [Line Items]
Percent of Fair Market Value on Grant Date Not Less Than	100.00%	100.00%
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period	over four years
Share-based Compensation Arrangement by Share-based Payment Award Expiration Date	ten years from the date of grant
Stock Appreciation Rights of Plans 2009 and 2011 [Member]
Employee Equity Incentive Plans [Line Items]
Percent of Fair Market Value on Grant Date Not Less Than	100.00%	100.00%
Share-based Compensation Arrangement by Share-based Payment Award Expiration 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	652,963
Zilog 2002 Plan [Member]
Employee Equity Incentive Plans [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award Number Of Shares Assumed	366,589	366,589
Employee Stock Purchase Plan 1999 [Member]
Employee Equity Incentive Plans [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized	500,000	500,000
ESPP Discounted Purchase Price Percentage	85.00%	85.00%
ESPP Offering Period	semi-annual
Share-based Compensation Arrangement by Share-based Payment Award, Maximum Employee Subscription Rate	15.00%	15.00%
Stock Issued During Period, Shares, Employee Stock Purchase Plans		55,925
Number of Employee Stock Purchase Plan Shares Available For Future Issuance	245,946	245,946
Subsequent ESPP Purchase Approval on July 31, 2007 [Member]
Employee Equity Incentive Plans [Line Items]
Number of Shares Approved in Subsequent Amendments of Original Purchase Plan	350,000	350,000
Subsequent ESPP Purchase Approval on July 9, 2010 [Member]
Employee Equity Incentive Plans [Line Items]
Number of Shares Approved in Subsequent Amendments of Original Purchase Plan	350,000	350,000
Equity Incentive Plans Total [Member]
Employee Equity Incentive Plans [Line Items]
Unrecognized Compensation Cost of Stock Option Granted	6.0	6.0
Weighted Average Period of the Unrecognized Compensation Cost to be Recognized	2.8

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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

Represents the purchase date set up in the 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 number of shares approved in subsequent amendments of the original 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

Award expiration date from the date of grant.

+ 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.

+ Details

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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 Statement of Financial Accounting Standard (FAS)

-Number 123R

-Paragraph A240

-Subparagraph h

-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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-Topic 718

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-Paragraph 2

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- Definition

The weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, using a decimal to express in number of years.

+ References

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- Definition

Description of the period of time over 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, which may be expressed in a variety of ways (for example, in years, month and year).

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 123R

-Paragraph A240

-Subparagraph a

-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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- 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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 123R

-Paragraph 65

-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

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-Number 123R

-Paragraph A240

-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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- 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

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 123R

-Paragraph A240

-Subparagraph a

-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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- 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 SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 29, 30

-Article 5

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-Publisher AICPA

-Name Accounting Principles Board Opinion (APB)

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