Unaudited Condensed Consolidated Statements of Cash Flows - USD ($) $ in Thousands	9 Months Ended
	Sep. 29, 2019	Sep. 30, 2018
Cash flows from operating activities:
Net income	$ 26,211	$ 9,510
Net loss from discontinued operations	0	8,351
Adjustments to reconcile net income to net cash provided by (used in) operating activities:
Depreciation and amortization	14,577	14,260
Stock-based compensation	20,183	20,228
Deferred income taxes	503	53
Other Noncash Income (Expense)	253	519
Changes in assets and liabilities
Accounts receivable	55,597	18,760
Inventories	(31,713)	(36,326)
Prepaid expenses and other assets	2,960	(5,443)
Accounts payable	(54,574)	26,546
Accrued employee compensation	(13,562)	(1,521)
Other accrued liabilities	(45,240)	(5,384)
Deferred revenue	(4,152)	3,620
Income taxes payable	(7,087)	(10,432)
Net cash provided by (used in) continuing operating activities	(36,044)	42,741
Net cash provided by discontinued operating activities	0	31,115
Net cash provided by (used in) operating activities	(36,044)	73,856
Cash flows from investing activities:
Purchases of short-term investments	(282)	(70,157)
Proceeds from maturities of short-term investments	70,786	102,054
Purchases of property and equipment	(11,797)	(8,950)
Proceeds from Sale, Maturity and Collection of Investments	0	624
Purchases of long-term investments	(5,484)	0
Payments to Acquire Businesses, Net of Cash Acquired	0	14,352
Net cash provided by continuing investing activities	53,223	9,219
Net cash used in discontinued investing activities	0	(50,707)
Net cash provided by (used in) investing activities	53,223	(41,488)
Cash flows from financing activities:
Repurchases of common stock	(52,365)	(15,000)
Restricted stock unit withholdings	(6,058)	(7,583)
Proceeds from exercise of stock options	4,582	5,183
Proceeds from issuance of common stock under employee stock purchase plan	3,617	5,554
Net cash used in continuing financing activities	(50,224)	(11,846)
Cash Provided by (Used in) Financing Activities, Discontinued Operations	0	170,248
Net cash provided by (used in) financing activities	(50,224)	158,402
Net increase (decrease) in cash and cash equivalents	(33,045)	190,770
Cash and cash equivalents, at beginning of period	201,047	202,870
Cash and cash equivalents, at end of period	168,002	393,640
Non-cash investing and financing activities:
Additions to property and equipment included in accounts payable and other accrued liabilities	3,174	(257)
Business Combination, Contingent Consideration, Liability, Noncurrent	$ 0	$ 5,953