CONSOLIDATED STATEMENTS OF CASH FLOWS $ in Thousands	12 Months Ended
	Dec. 28, 2019 USD ($)	Dec. 29, 2018 USD ($)	Dec. 30, 2017 USD ($)
Cash flows from operating activities:
Net income (loss)	$ 43,493	$ (26,322)	$ (70,562)
Adjustments to reconcile net income (loss) to net cash provided by operating activities:
Depreciation and amortization	33,056	39,261	57,861
Impairment of acquired intangible assets	0	12,486	32,431
Stock-based compensation expense	18,899	13,646	12,543
Reduction in the carrying amount of right-of-use assets	5,797	0	0
Loss on re-financing of long-term debt	2,235	0	0
Amortization of debt issuance costs and discount	1,659	2,230	1,982
Impairment of operating lease right-of-use asset (recorded in Restructuring charges)	977
Impairment of operating lease right-of-use asset (recorded in Restructuring charges)	4,664	17,349	7,196
Gain on sale of building	0	0	(4,624)
Loss on sale of assets and business units	0	0	1,496
Other non-cash adjustments	(374)	(79)	1,707
Changes in assets and liabilities:
Accounts receivable, net	(4,027)	(3,978)	44,613
Inventories	12,116	13,177	(902)
Prepaid expenses and other assets	3,740	(11,667)	889
Accounts payable and accrued expenses (includes restructuring)	9,261	13,325	(23,588)
Accrued payroll obligations	4,039	(1,051)	726
Operating lease liabilities, current and long-term portions	(6,896)
Income taxes payable	162	498	(556)
Deferred income and allowances on sales to distributors		0
Net cash provided by operating activities	124,137	51,458	38,514
Cash flows from investing activities:
Proceeds from sales of and maturities of short-term marketable securities	9,655	5,000	12,689
Purchases of marketable securities	0	(9,603)	(7,420)
Proceeds from sale of building	0	0	7,895
Cash paid for costs of sale of building	0	0	(1,004)
Capital expenditures	(15,590)	(8,384)	(12,855)
Proceeds from sale of assets and business units, net of cash sold	0	0	967
Repayment received on short-term loan to cost-method investee	0	0	2,000
Short-term loan to cost-method investee	0	0	(2,000)
Cash paid for software licenses	(9,601)	(8,123)	(8,532)
Net cash used in investing activities	(15,536)	(21,110)	(8,260)
Cash flows from financing activities:
Restricted stock unit tax withholdings	(10,084)	(2,370)	(3,267)
Proceeds from issuance of common stock	17,166	29,288	6,085
Proceeds from issuance of long-term debt	206,500	0	0
Original issue discount and debt issuance costs	(2,086)	0	0
Repayment of debt	(321,408)	(43,759)	(35,429)
Net cash used in financing activities	(109,912)	(16,841)	(32,611)
Effect of exchange rate change on cash	341	(1,271)	2,620
Net (decrease) increase in cash and cash equivalents	(970)	12,236	263
Beginning cash and cash equivalents	119,051	106,815	106,552
Ending cash and cash equivalents	118,081	119,051	106,815
Supplemental disclosure of cash flow information and non-cash investing and financing activities:
Interest paid	10,995	18,607	20,649
Operating lease payments	8,425
Income taxes paid, net of refunds	3,393	3,054	2,387
Accrued purchases of property and equipment	826	110	588
Operating lease right-of-use assets obtained in exchange for lease obligations	747
Note receivable resulting from sale of assets and business units	0	0	3,050
Product
Changes in assets and liabilities:
Deferred income and allowances on sales to distributors	0	0	(15,007)
Licensing and services
Changes in assets and liabilities:
Deferred income and allowances on sales to distributors	$ 0	$ (68)	$ (495)