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           Consolidated Statements of Shareholders' Equity (Parenthetical) (USD $) 
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        12 Months Ended | ||
|---|---|---|---|
| 
           Dec. 31, 2011 
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           Jan. 01, 2011 
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           Jan. 02, 2010 
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| Increase (Decrease) in Stockholders' Equity [Roll Forward] | |||
| Payment of dividends (in dollars per share) | $ 0.25 | $ 0.50 | $ 0.10 | 
| Issuance of shares of common stock from the treasury (in shares) | 18,280 | 13,949 | 19,042 | 
| Stock options exercised (in shares) | 18,155 | 8,884 | 0 | 
| X | ||||||||||
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- Definition 
          Aggregate dividends declared during the period for each share of common stock outstanding. Reference 1: http://www.xbrl.org/2003/role/presentationRef 
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- Details 
          
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- Definition 
          Number of share options (or share units) exercised during the current period. Reference 1: http://www.xbrl.org/2003/role/presentationRef 
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- Definition 
          Number of treasury shares (units) reissued during the period, excluding reissuance of shares (units) held in treasury used to satisfy equity-based compensation obligations exercised by the holders of such rights. Upon reissuance of shares (units) from treasury, either the common or preferred stock (unit) reissued is outstanding. Reference 1: http://www.xbrl.org/2003/role/presentationRef 
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