Acquisitions and Acquisition-Related Contingent Consideration (Details) (USD $)	9 Months Ended		3 Months Ended	9 Months Ended		12 Months Ended
	Sep. 29, 2012	Dec. 31, 2011	Sep. 29, 2012 Sigrity [Member]	Sep. 29, 2012 Sigrity [Member]	Jul. 02, 2012 Sigrity [Member]	Dec. 31, 2011 2011 Acquisitions [Member]	Sep. 29, 2012 2011 Acquisitions [Member]
Acquisitions (Textual) [Abstract]
Total consideration paid to acquire business, net of cash acquired					$ 78,500,000
Cash acquired					7,500,000
Additional payments deferred on the acquisition date					14,200,000
Cash paid for acquired entity at closing					64,300,000
Additional payments deferred on the acquisition date, expensed in current period			1,800,000
Additional payments deferred on the acquisition date, expense over designated retention periods					12,400,000
Valuation Allowance, Deferred Tax Asset, Change in Amount			14,800,000	14,800,000
Acquisition-Related Contingent Consideration (Textual) [Abstract]
Maximum payments for contingent consideration arrangement						5,000,000
Time of certain financial measures subsequent to the consummation of the acquisition related to contingent consideration						3 years
Beginning date of acquisition related contingent consideration measurement period						subsequent to October 1, 2011
Acquisition related contingent consideration at initial fair value						3,500,000
Acquisition-related contingent consideration at fair value	4,108,000	3,911,000					4,000,000
Acquisition-Related Contingent Consideration (Additional Textual) [Abstract]
Maximum amount obligated to pay by Cadence	18,800,000
Period over which consideration may be paid	43 months
Portion of amount of contingent consideration potential expense in future periods	$ 12,500,000