CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 29, 2013	Mar. 30, 2012
Cash flows from operating activities:
Net income (loss)	$ 6,421	$ (7,528)
Adjustments to reconcile net income (loss) to net cash provided by operating activities:
Amortization of intangibles	7,033	7,539
Depreciation	4,040	3,798
Stock-based compensation	3,986	4,800
Gain on sale of discontinued operations, net of tax	(14,956)
Loss on impairment of fixed assets	101
Deferred income taxes	(204)	(1,262)
Provision for inventories	567	784
Allowance for doubtful accounts, returns and discounts	1,116	(180)
Excess tax benefits from stock-based compensation		(73)
Other non-cash adjustments, net	408	(8)
Changes in assets and liabilities:
Accounts receivable	(10,888)	(1,683)
Inventories	6,832	4,320
Prepaid expenses and other assets	(8,597)	1,892
Accounts payable	(2,796)	936
Deferred revenue	2,667	2,740
Income taxes payable	(1,257)	(929)
Accrued and other liabilities	(216)	(7,255)
Net cash (used in) provided by operating activities	(5,743)	7,891
Cash flows from investing activities:
Purchases of investments	(25,908)	(36,654)
Proceeds from maturities of investments	16,249	18,791
Proceeds from sales of investments	4,000	1,042
Acquisition of property and equipment	(4,274)	(3,715)
Proceeds from sale of discontinued operations, net of selling costs	44,336
Net cash provided by (used in) investing activities	34,403	(20,536)
Cash flows from financing activities:
Payments for repurchase of common stock	(9,268)
Proceeds from issuance of common stock, net	2,508	2,479
Excess tax benefits from stock-based compensation		73
Net cash (used in) provided by financing activities	(6,760)	2,552
Effect of exchange rate changes on cash and cash equivalents	(106)	129
Net increase (decrease) in cash and cash equivalents	21,794	(9,964)
Cash and cash equivalents at beginning of period	96,670	90,983
Cash and cash equivalents at end of period	$ 118,464	$ 81,019