Quarterly report pursuant to Section 13 or 15(d)

Basis of Presentation (Details)

v2.4.0.6
Basis of Presentation (Details) (USD $)
In Millions, unless otherwise specified
3 Months Ended 9 Months Ended 3 Months Ended 9 Months Ended
Sep. 29, 2012
Oct. 01, 2011
Sep. 29, 2012
Oct. 01, 2011
Sep. 29, 2012
Test Systems Segment [Member]
Oct. 01, 2011
Test Systems Segment [Member]
Sep. 29, 2012
Test Systems Segment [Member]
Oct. 01, 2011
Test Systems Segment [Member]
Nov. 30, 2011
Ballard [Member]
Jul. 30, 2012
Max-Viz, Inc [Member]
Basis of Presentation (Textual) [Abstract]                    
Percentage of acquired stock                 100.00% 100.00%
Percentage of Revenue Recognized from Long Term Fixed Price Contracts         32.00% 58.00% 37.00% 76.00%    
Basis of Presentation (Additional Textual) [Abstract]                    
Research and development, design and related engineering $ 12.8 $ 9.5 $ 33.9 $ 26.6