Revenue from Contracts with Customers - Schedule of New Accounting Standard Impact on Financial Statements (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 28, 2019	Sep. 28, 2019	Jun. 29, 2019	Mar. 30, 2019	Dec. 29, 2018	Sep. 29, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 28, 2019	Dec. 29, 2018	Dec. 30, 2017
Condensed Consolidated Statement of Operations
Revenue	$ 100,237	$ 103,469	$ 102,296	$ 98,091	$ 95,977	$ 101,484	$ 102,715	$ 98,623	$ 404,093	$ 398,799	$ 385,961
Net loss	13,987	13,539	8,559	7,408	(7,121)	6,974	(20,223)	(5,952)	43,493	(26,322)	(70,562)
Cost of revenue									165,671	$ 179,360	169,382
Net loss per share, basic and diluted (in dollars per share)										$ (0.21)
Condensed Consolidated Balance Sheets
Accounts receivable, net of allowance for doubtful accounts	64,917				60,890				64,917	$ 60,890
Inventories	54,980				67,096				54,980	67,096
Prepaid expenses and other current assets	24,452				27,762				24,452	27,762
Total assets	612,016				623,687				612,016	623,687
Accounts payable and accrued expenses (includes restructuring)	60,255				51,763				60,255	51,763
Deferred income and allowances on sales to distributors					0					0
Accumulated deficit	(433,290)				(476,783)				(433,290)	(476,783)
Total liabilities and stockholders' equity	612,016				623,687				612,016	623,687
Condensed Consolidated Statement of Cash Flows
Net income (loss)	$ 13,987	$ 13,539	$ 8,559	$ 7,408	(7,121)	$ 6,974	$ (20,223)	$ (5,952)	43,493	(26,322)	(70,562)
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)
Deferred income and allowances on sales to distributors										0
Adjustments | Accounting Standards Update 2014-09
Condensed Consolidated Statement of Operations
Net loss										$ (9,177)
Net loss per share, basic and diluted (in dollars per share)										$ (0.07)
Condensed Consolidated Balance Sheets
Accounts receivable, net of allowance for doubtful accounts					6,600					$ 6,600
Inventories					78					78
Prepaid expenses and other current assets					(9,775)					(9,775)
Total assets					(3,097)					(3,097)
Accounts payable and accrued expenses (includes restructuring)					(1,156)					(1,156)
Deferred income and allowances on sales to distributors					34,637					34,637
Accumulated deficit					(36,578)					(36,578)
Total liabilities and stockholders' equity					(3,097)					(3,097)
Condensed Consolidated Statement of Cash Flows
Net income (loss)										(9,177)
Accounts receivable, net										(8,408)
Inventories										(448)
Prepaid expenses and other assets										2,260
Accounts payable and accrued expenses (includes restructuring)										(1,614)
Deferred income and allowances on sales to distributors										17,387
Pro forma as if previous standard was in effect
Condensed Consolidated Statement of Operations
Net loss										$ (35,499)
Net loss per share, basic and diluted (in dollars per share)										$ (0.28)
Condensed Consolidated Balance Sheets
Accounts receivable, net of allowance for doubtful accounts					67,490					$ 67,490
Inventories					67,174					67,174
Prepaid expenses and other current assets					17,987					17,987
Total assets					620,590					620,590
Accounts payable and accrued expenses (includes restructuring)					50,607					50,607
Deferred income and allowances on sales to distributors					34,637					34,637
Accumulated deficit					(513,361)					(513,361)
Total liabilities and stockholders' equity					$ 620,590					620,590
Condensed Consolidated Statement of Cash Flows
Net income (loss)										(35,499)
Accounts receivable, net										(12,386)
Inventories										12,729
Prepaid expenses and other assets										(9,407)
Accounts payable and accrued expenses (includes restructuring)										11,711
Deferred income and allowances on sales to distributors										17,387
Product
Condensed Consolidated Statement of Operations
Revenue									382,548	380,468	356,502
Cost of revenue										179,101
Condensed Consolidated Statement of Cash Flows
Deferred income and allowances on sales to distributors									0	0	(15,007)
Product | Adjustments | Accounting Standards Update 2014-09
Condensed Consolidated Statement of Operations
Revenue										(14,098)
Cost of revenue										(6,399)
Product | Pro forma as if previous standard was in effect
Condensed Consolidated Statement of Operations
Revenue										366,370
Cost of revenue										172,702
Licensing and services
Condensed Consolidated Statement of Operations
Revenue									21,545	18,331	29,459
Condensed Consolidated Statement of Cash Flows
Deferred income and allowances on sales to distributors									$ 0	(68)	$ (495)
Licensing and services | Adjustments | Accounting Standards Update 2014-09
Condensed Consolidated Statement of Operations
Revenue										(1,478)
Licensing and services | Pro forma as if previous standard was in effect
Condensed Consolidated Statement of Operations
Revenue										$ 16,853