Condensed Consolidated Statements of Cash Flows (Unaudited) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 30, 2013	Mar. 31, 2012
Statement of Cash Flows [Abstract]
Cash and cash equivalents at beginning of period	$ 726,357	$ 601,602
Cash flows from operating activities:
Net income	78,609	31,104
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	21,682	21,939
Amortization of debt discount and fees	6,281	5,734
Stock-based compensation	13,810	11,525
Gain on investments, net	(1,006)	(1,949)
Deferred income taxes	8,695	223
Provisions (recoveries) for losses (gains) on receivables, net	(85)	0
Other non-cash items	(922)	746
Changes in operating assets and liabilities, net of effect of acquired businesses:
Receivables	23,652	60,172
Inventories	(979)	(154)
Prepaid expenses and other	(1,099)	(5,545)
Other assets	4,148	(577)
Accounts payable and accrued liabilities	(11,003)	(19,582)
Deferred revenue	(16,648)	(39,315)
Other long-term liabilities	(49,799)	(3,612)
Net cash provided by operating activities	75,336	60,709
Cash flows from investing activities:
Purchases of available-for-sale securities	(24,282)	0
Proceeds from the sale of available-for-sale securities	14,985	0
Proceeds from the maturity of available-for-sale securities	8,700	0
Proceeds from the sale of long-term investments	6,102	44
Purchases of property, plant and equipment	(6,569)	(8,201)
Investment in venture capital partnerships and equity investments	0	(250)
Cash paid in business combinations and asset acquisitions, net of cash acquired	(757)	(1,041)
Net cash used for investing activities	(1,821)	(9,448)
Cash flows from financing activities:
Principal payments on receivable financing	(2,526)	0
Payment of acquisition-related contingent consideration	(582)	(39)
Tax effect related to employee stock transactions allocated to equity	5,276	2,842
Proceeds from issuance of common stock	21,801	12,761
Stock received for payment of employee taxes on vesting of restricted stock	(8,775)	(6,173)
Net cash provided by financing activities	15,194	9,391
Effect of exchange rate changes on cash and cash equivalents	(4,914)	(2,567)
Increase in cash and cash equivalents	83,795	58,085
Cash and cash equivalents at end of period	810,152	659,687
Supplemental cash flow information:
Interest paid	183	0
Income taxes paid (refunded), including foreign withholding tax	(21)	4,699
Non-cash investing and financing activities:
Available-for-sale securities received from customer	209	15
Receivables related to sales of available-for-sale securities	$ 0	$ 122