Condensed Consolidated Statements of Cash Flows (USD $) In Thousands, unless otherwise specified	6 Months Ended
	Jun. 29, 2013	Jun. 30, 2012
Operating Activities
Net income	$ 32,646	$ 34,829
Adjustments to reconcile net income to cash provided by operating activities:
Depreciation of property and equipment	6,634	6,749
Amortization of other intangible assets and other assets	5,635	4,559
Stock-based compensation expense	13,684	15,865
Income tax benefit (detriment) from employee stock-based awards	(489)	2,627
Excess income tax benefit from employee stock-based awards	(243)	(2,450)
Deferred income taxes	9,277	1,625
Changes in operating assets and liabilities:
Accounts receivable	9,388	(17,315)
Inventories	(1,028)	(1,299)
Prepaid expenses and other assets	5,023	4,806
Accounts payable	(2,271)	8,766
Accrued expenses	(6,013)	(5,203)
Deferred income on shipments to distributors	293	1,372
Income taxes	(6,439)	(13,672)
Net cash provided by operating activities	66,097	41,259
Investing Activities
Purchases of available-for-sale investments	(121,994)	(105,169)
Proceeds from sales and maturities of available-for-sale investments	146,870	186,514
Purchases of property and equipment	(6,498)	(5,095)
Purchases of other assets	(2,438)	(7,919)
Net cash provided by investing activities	15,940	68,331
Financing Activities
Proceeds from issuance of common stock, net of shares withheld for taxes	9,512	2,922
Excess income tax benefit from employee stock-based awards	243	2,450
Repurchases of common stock		(36,173)
Payments on debt	(3,750)
Net cash provided by (used) in financing activities	6,005	(30,801)
Increase in cash and cash equivalents	88,042	78,789
Cash and cash equivalents at beginning of period	105,426	94,964
Cash and cash equivalents at end of period	$ 193,468	$ 173,753