Condensed Consolidated Statements of Cash Flows (Unaudited) (USD $) In Thousands	6 Months Ended
	Jul. 02, 2011	Jul. 03, 2010
Operating activities
Net income (loss)	$ (9,650)	$ 13,767
Adjustments to reconcile net income (loss) to net cash and cash equivalents provided by (used in) operating activities:
Depreciation and amortization	2,825	2,922
Net amortization of investment premiums and discounts	571
Loss on sale of investments	150
Equity-based compensation	2,046	1,583
Change in the fair value of acquisition-related contingent consideration	573
Deferred income taxes	(4,738)	2,094
Loss (gain) on disposal of equipment	(109)	122
Changes in operating assets and liabilities	(3,297)	(20,396)
Total adjustments	(1,979)	(13,675)
Net cash and cash equivalents provided by (used in) operating activities	(11,629)	92
Investing activities
Purchases of investments	(87,040)	(2,999)
Proceeds from sales and maturities of investments	23,095	13,200
Proceeds from sale of equipment	241
Purchases of leasehold improvements and equipment	(4,068)	(2,342)
Net cash and cash equivalents provided by (used in) investing activities	(67,772)	7,859
Financing activities
Net proceeds from issuance of common stock	1,755	1,231
Net cash and cash equivalents provided by financing activities	1,755	1,231
Effect of exchange rate changes on cash and cash equivalents	16	33
Net increase (decrease) in cash and cash equivalents	(77,630)	9,215
Cash and cash equivalents at beginning of period	109,520	17,592
Cash and cash equivalents at end of period	$ 31,890	$ 26,807