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Discontinuation of Business Unit (Details) - USD ($) $ in Thousands	3 Months Ended			9 Months Ended
	Sep. 29, 2018	Jun. 30, 2018	Sep. 30, 2017	Sep. 29, 2018	Sep. 30, 2017
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Nonoperating expense	$ 88,525		$ 129,439	$ 304,222	$ 337,594
Impairment of acquired intangible assets	586	$ 11,900	36,198	12,486	36,198
Restructuring charges	90		3,071	5,495	4,713
Product
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Cost of revenue	43,120		$ 38,032	$ 137,430	$ 120,395
Discontinued Operations \| Millimeter Wave Business
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Nonoperating expense	24,000
Impairment of acquired intangible assets	11,900
Restructuring charges	4,100
Discontinued Operations \| Millimeter Wave Business \| Product
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Cost of revenue	$ 8,000