Annual report pursuant to Section 13 and 15(d)

Segments (Details Textual)

v2.4.0.6
Segments (Details Textual) (USD $)
 3 Months Ended 12 Months Ended
Dec. 31, 2012
Sep. 29, 2012
Jun. 30, 2012
Mar. 31, 2012
Dec. 31, 2011
Oct. 01, 2011
Jul. 02, 2011
Apr. 02, 2011
Dec. 31, 2012
Customer
Dec. 31, 2011
Dec. 31, 2010
Goodwill [Line Items]                      
Goodwill $ 21,923,000       $ 17,185,000       $ 21,923,000 $ 17,185,000 $ 7,610,000
Goodwill impairment loss                 0 2,400,000 0
Purchased intangible impairment loss                 0   0
Sales 67,420,000 68,899,000 64,989,000 65,138,000 61,156,000 56,404,000 55,475,000 55,128,000 266,446,000 228,163,000 195,754,000
Net Income 5,655,000 4,930,000 5,194,000 6,095,000 5,169,000 6,665,000 4,548,000 5,209,000 21,874,000 21,591,000 14,948,000
Segments (Textual) [Abstract]                      
Number of major customers                 2    
Exchange loss in determining net income                 100,000 100,000 100,000
Cumulative translation adjustments 1,415,000       1,232,000       1,415,000 1,232,000  
Canada [Member]
                      
Goodwill [Line Items]                      
Sales                 13,000,000 12,200,000 9,100,000
Net Income                 1,000,000 900,000 100,000
Foreign Country [Member]
                      
Goodwill [Line Items]                      
Net assets 6,700,000       6,600,000       6,700,000 6,600,000  
Aerospace Segment [Member]
                      
Goodwill [Line Items]                      
Goodwill 21,900,000       17,200,000       21,900,000 17,200,000  
Goodwill impairment loss                 0   0
Purchased intangible impairment loss                 0   0
Test Systems Segment [Member]
                      
Goodwill [Line Items]                      
Goodwill 0       0       0 0  
Goodwill impairment loss                 0 2,400,000 0
Purchased intangible impairment loss                 $ 0 $ 100,000 $ 0