| 
           Fair Value - Additional Information (Detail) (USD $) 
         | 
        1 Months Ended | 6 Months Ended | ||||||
|---|---|---|---|---|---|---|---|---|
| 
           Jun. 29, 2013 
         | 
        
           Dec. 31, 2012 
         | 
        
           Jul. 30, 2012
 
          Max-Viz, Inc. [Member] 
         | 
        
           Jun. 29, 2013
 
          Max-Viz, Inc. [Member] 
         | 
        
           Jun. 29, 2013
 
          Ballard [Member] 
         | 
        
           Jun. 29, 2013
 
          Test Systems [Member] 
         | 
        
           Jun. 29, 2013
 
          Maximum [Member]
 
          Max-Viz, Inc. [Member] 
         | 
        
           Jun. 29, 2013
 
          Maximum [Member]
 
          Ballard [Member] 
         | 
      |
| Fair Value Of Assets And Liabilities Measured On Non Recurring Basis [Line Items] | ||||||||
| Revenue growth target period | 3 years | 3 years | 4 years | |||||
| Contingent consideration on fair value liabilities | $ 746,000 | $ 814,000 | $ 8,000,000 | $ 5,500,000 | ||||
| Total amortized intangible assets | $ 3,900,000 | |||||||
| X | ||||||||||
| 
             
- Details 
          
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| X | ||||||||||
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- Definition 
          Period for meeting revenue growth targets as condition of contingent consideration. No definition available. 
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| X | ||||||||||
| 
             
- Definition 
          Amount of liability recognized arising from contingent consideration in a business combination. Reference 1: http://www.xbrl.org/2003/role/presentationRef 
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| X | ||||||||||
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- Definition 
          Fair value portion of assets, excluding financial assets, that lack physical substance, having a limited useful life. Reference 1: http://www.xbrl.org/2003/role/presentationRef 
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