Quarterly report pursuant to Section 13 or 15(d)

Basis of Presentation - Additional Information (Detail)

v2.4.0.8
Basis of Presentation - Additional Information (Detail) (USD $)
In Millions, unless otherwise specified
3 Months Ended 6 Months Ended
Jun. 28, 2014
Jun. 29, 2013
Jun. 28, 2014
Contract
Segment
Location
Jun. 29, 2013
Schedule Of Accounting Policies [Line Items]        
Reportable segments     2  
Number of Primary locations     12  
Significant contracts with right of return     0  
Contractual life of service     24 months  
Research and development, design and related engineering $ 20.6 $ 13.3 $ 37.9 $ 26.1
Test Systems [Member]
       
Schedule Of Accounting Policies [Line Items]        
Percentage of revenue recognized from long term fixed price contracts 1.00% 30.00% 2.00% 28.00%
United States [Member]
       
Schedule Of Accounting Policies [Line Items]        
Number of Primary locations     10  
Canada [Member]
       
Schedule Of Accounting Policies [Line Items]        
Number of Primary locations     1  
France [Member]
       
Schedule Of Accounting Policies [Line Items]        
Number of Primary locations     1