Note 13 Employee Savings and Retirement Plans (Narratives) (Details) (USD $)	12 Months Ended
Mar. 31, 2013	Mar. 31, 2012	Mar. 31, 2011
Plan 401(k) [Member]
Defined Contribution Pension and Other Postretirement Plans [Line Items]
Defined Contribution Plan, Employer Contribution	$ 625,000	$ 571,000	$ 590,000
Employer Contribution Vesting Percentage	100.00%
Westcode Semiconductor Group Personal Pension [Member]
Defined Contribution Pension and Other Postretirement Plans [Line Items]
Defined Contribution Plan, Employer Contribution	$ 298,000	$ 344,000	$ 337,000
Minimum Percentage of Employees Contribution	2.50%
Maximum Percentage of Employees Contribution	4.50%
Minimum Percentage of Employees Contribution Matched by Employer	5.00%
Maximum Percentage of Employees Contribution Matched by Employer	7.00%
Employer Contribution Vesting Percentage	100.00%

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The amount of employer's contribution during the period to defined contribution plan or other postretirement plans.

No definition available.

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Vesting percentage of employer's contribution to the defined contribution plan or other postretirement plans.

No definition available.

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The maximum percentage that employees can contribute from the pensionable salary.

No definition available.

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The maximum percentage of employee's contribution matched by employer.

No definition available.

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The minimum percentage that employees can contribute from the pensionable salary.

No definition available.

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The minimum percentage of employee's contribution matched by employer.

No definition available.

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