Goodwill and Acquired Intangibles (Details) (USD $) In Thousands, unless otherwise specified	9 Months Ended
	Sep. 29, 2012
Changes in the carrying amount of goodwill
Balance as of December 31, 2011	$ 192,125
Effect of foreign currency translation	429
Balance as of September 29, 2012	233,275
Goodwill resulting from acquisitions [Member]
Changes in the carrying amount of goodwill
Goodwill, Acquired During Period	39,680
Additions due to contingent consideration [Member]
Changes in the carrying amount of goodwill
Goodwill, Acquired During Period	$ 1,041	[1]

[1] Cadence accounts for business combinations with acquisition dates on or before January 3, 2009 under the purchase method in accordance with accounting standards that were authoritative at that time, whereby contingent consideration is added to goodwill as it is earned.