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Stock Based Compensation (Details Textual)
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3 Months Ended | 3 Months Ended | ||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
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Mar. 30, 2013
USD ($)
OptionPlan
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Mar. 31, 2012
USD ($)
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Mar. 30, 2013
Director Equity Plan [Member]
USD ($)
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Mar. 31, 2012
Director Equity Plan [Member]
USD ($)
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Mar. 30, 2013
2006 Stock Option Plan [Member]
Awards
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Mar. 30, 2013
2001 Restricted Stock Plan [Member]
USD ($)
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Mar. 31, 2012
2001 Restricted Stock Plan [Member]
USD ($)
|
Mar. 30, 2013
Equity Incentive Plan (2011 Plan) [Member]
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Mar. 30, 2013
Nonemployee Director Equity and Deferred Compensation Plan [Member]
USD ($)
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Mar. 30, 2013
Employee Stock Purchase Plan [Member]
USD ($)
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Mar. 31, 2012
Employee Stock Purchase Plan [Member]
USD ($)
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Mar. 30, 2013
Employee Stock Purchase Plan and U.K. Plan [Member]
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Mar. 30, 2013
Maximum [Member]
2006 Stock Option Plan [Member]
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Mar. 30, 2013
Minimum [Member]
Employee Stock Purchase Plan [Member]
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Mar. 30, 2013
Minimum [Member]
Employee Stock Purchase Plan [Member]
United States [Member]
USD ($)
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Mar. 30, 2013
Minimum [Member]
Employee Stock Purchase Plan [Member]
United Kingdom [Member]
GBP (£)
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| Stock Option Plans (Textual) [Abstract] | ||||||||||||||||
| Shares available for issuance | 25,000 | 1,125,000 | 928,125 | 252,249 | ||||||||||||
| Exercise price per share not less than fair value percent | 110.00% | |||||||||||||||
| Exercise price per share more than voting stock | 10.00% | |||||||||||||||
| Stock options maximum term (in years) | 10 years | |||||||||||||||
| Number of awards granted under 2006 plan | 0 | |||||||||||||||
| Minimum period before shares become non-forfeitable (in months) | 6 months | |||||||||||||||
| Plan Expiration year | 2011 | |||||||||||||||
| Aggregate shares of restricted stock grant | 1,000,000 | 1,096,875 | ||||||||||||||
| Remaining number of shares to be issued | 270,000 | 823,912 | 701,346,000 | |||||||||||||
| Restricted stock expense | $ 519,000 | $ 418,000 | ||||||||||||||
| Rate of common stock at market value | 85.00% | |||||||||||||||
| Share based Compensation Expenses under Director's plan | 156,000 | 234,000 | ||||||||||||||
| Shares purchase by employees under ESPP | 11,938 | 8,460 | ||||||||||||||
| Shares allowed to be purchased by U.S. employees and U.K. employees | 25,000 | 1,500 | ||||||||||||||
| Allowable purchase rate of common stock based on annual salary | 10.00% | |||||||||||||||
| Weighted average price | $ 22.35 | $ 16.73 | ||||||||||||||
| Stock option granted, shares | 4,500 | 3,853 | 375 | |||||||||||||
| Cash fees paid | 3,000 | |||||||||||||||
| Fee for the chairs of each Board committee | 125.00% | 25.00% | ||||||||||||||
| Common stock shares for each nonemployee director | 500 | |||||||||||||||
| Stock Option Plans (Additional Textual) [Abstract] | ||||||||||||||||
| Total unrecognized compensation | 3,132,000 | |||||||||||||||
| Number of plan under which restricted stock unit granted | 2 | |||||||||||||||
| Recognized weighted average period (in years) | 1 year 3 months 29 days | |||||||||||||||
| Deferred stock units outstanding | 0 | |||||||||||||||
| Share based Compensation Expenses | $ 45,000 | $ 54,000 | ||||||||||||||
| Ratio for additional common stock shares issued, under ESPP | 6 | |||||||||||||||