Balance Sheet Account Details (Details 4) (USD $) In Thousands, unless otherwise specified	Apr. 01, 2012	Jan. 01, 2012
Accrued Liabilities, Current [Abstract]
Deferred revenue, current portion	$ 59,572	$ 52,573
Accrued compensation expenses	41,759	52,035
Accrued taxes payable	23,336	19,339
Customer deposits	19,362	17,958
Reserve for product warranties	11,871	11,966
Deferred rent, current portion	8,943	11,042
Acquisition related contingent consideration liability, current portion	8,375	2,335
Facility exit obligation, current portion	4,389	4,408
Accrued unsolicited tender offer related expenses	3,165
Accrued royalties	2,757	5,682
Other accrued expenses	14,511	10,436
Total accrued liabilities	$ 198,040	$ 187,774