Condensed Consolidated Statements Of Cash Flows (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Apr. 04, 2014	Mar. 29, 2013
Cash flow from operating activities:
Net income	$ 68,125	$ 48,932
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation expense	7,520	6,193
Amortization expense	40,569	39,332
Provision for doubtful accounts	516	65
Deferred income taxes	(1,454)	(11,809)
Stock-based compensation	10,112	8,818
Income from equity method investments	(3,463)	(4,257)
Gain on an equity sale	(15,091)	0
Excess tax benefit for stock-based compensation	(10,211)	(4,784)
Provision for excess and obsolete inventories	1,089	584
Other non-cash items	(728)	104
Add decrease (increase) in assets:
Accounts receivable	(61,875)	(61,956)
Other receivables	(1,661)	5,027
Inventories	(13,395)	(20,218)
Other current and non-current assets	(2,224)	(10,867)
Add increase (decrease) in liabilities:
Accounts payable	10,487	(6,081)
Accrued compensation and benefits	(11,503)	(12,037)
Deferred revenue	47,077	51,964
Accrued warranty expense	382	439
Other liabilities	19,123	7,939
Net cash provided by operating activities	83,395	37,388
Cash flow from investing activities:
Acquisitions of businesses, net of cash acquired	(10,961)	(65,192)
Acquisitions of property and equipment	(13,574)	(14,927)
Dividends received from equity method investments	12,443	1,284
Other	(2,050)	2,430
Net cash used in investing activities	(14,142)	(76,405)
Cash flow from financing activities:
Issuances of common stock, net of tax withholding	32,465	14,437
Excess tax benefit for stock-based compensation	10,211	4,784
Proceeds from debt and revolving credit lines	17,000	113,000
Payments on debt and revolving credit lines	(110,805)	(103,981)
Net cash provided by (used in) financing activities	(51,129)	28,240
Effect of exchange rate changes on cash and cash equivalents	(125)	(3,442)
Net increase (decrease) in cash and cash equivalents	17,999	(14,219)
Cash and cash equivalents, beginning of period	147,227	157,771
Cash and cash equivalents, end of period	$ 165,226	$ 143,552