Unaudited Condensed Consolidated Statements Of Cash Flows - USD ($) $ in Thousands	9 Months Ended
	Oct. 01, 2017	Oct. 02, 2016
Cash flows from operating activities:
Net income	$ 51,370	$ 53,742
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	20,219	24,601
Purchase premium amortization/discount accretion on investments, net	102	106
Non-cash stock-based compensation	16,412	14,300
Income tax impact associated with stock option exercises	0	1,627
Deferred income taxes	(66)	1,327
Changes in assets and liabilities:
Accounts receivable	18,248	56,731
Inventories	(1,216)	(4,503)
Prepaid expenses and other assets	5,557	9,772
Accounts payable	(20,016)	5,428
Accrued employee compensation	(12,595)	(3,842)
Other accrued liabilities	12,918	(24,444)
Deferred revenue	10,326	(2,610)
Income taxes payable	173	1,082
Net cash provided by operating activities	101,432	133,317
Cash flows from investing activities:
Purchases of short-term investments	(101,951)	(117,994)
Proceeds from maturities of short-term investments	101,544	85,286
Purchase of property and equipment	(9,805)	(6,984)
Payments to cost method investments	(2,900)	0
Payments made in connection with business acquisition, net of cash acquired	(737)	0
Net cash used in investing activities	(13,849)	(39,692)
Cash flows from financing activities:
Repurchases of common stock	(86,630)	(23,252)
Restricted stock unit tax withholdings	(6,017)	(4,364)
Proceeds from exercise of stock options	6,405	21,874
Proceeds from issuance of common stock under employee stock purchase plan	4,764	3,892
Net cash used in financing activities	(81,478)	(1,850)
Net increase in cash and cash equivalents	6,105	91,775
Cash and cash equivalents, at beginning of period	240,468	181,945
Cash and cash equivalents, at end of period	$ 246,573	$ 273,720