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           Acquisitions - Consolidated Results of Operation of Company with Acquired Business (Detail) (Peco, Inc [Member], USD $) 
        In Thousands, except Per Share data, unless otherwise specified  | 
        3 Months Ended | 9 Months Ended | ||
|---|---|---|---|---|
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           Sep. 28, 2013 
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           Sep. 29, 2012 
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           Sep. 28, 2013 
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           Sep. 29, 2012 
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           Peco, Inc [Member] 
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| Loans At Acquisition Date [Line Items] | ||||
| Sales | $ 93,517 | $ 87,689 | $ 280,714 | $ 256,571 | 
| Net Income | $ 7,278 | $ 5,588 | $ 23,209 | $ 17,973 | 
| Basic Earnings Per Share | $ 0.42 | $ 0.33 | $ 1.33 | $ 1.05 | 
| Diluted Earnings Per Share | $ 0.40 | $ 0.31 | $ 1.27 | $ 0.99 | 
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- Details 
          
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- Definition 
          The pro forma basic net income per share for a period as if the business combination or combinations had been completed at the beginning of a period. Reference 1: http://www.xbrl.org/2003/role/presentationRef 
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| X | ||||||||||
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- Definition 
          The pro forma diluted net income per share for a period as if the business combination or combinations had been completed at the beginning of a period. Reference 1: http://www.xbrl.org/2003/role/presentationRef 
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| X | ||||||||||
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- Definition 
          The pro forma net Income or Loss for the period as if the business combination or combinations had been completed at the beginning of a period. Reference 1: http://www.xbrl.org/2003/role/presentationRef 
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| X | ||||||||||
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- Definition 
          The pro forma revenue for a period as if the business combination or combinations had been completed at the beginning of the period. Reference 1: http://www.xbrl.org/2003/role/presentationRef 
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