Selected Quarterly Financial Data Selected Quarterly Financial Data - Additional Information (Details) - USD ($) $ in Thousands	3 Months Ended							6 Months Ended	12 Months Ended
	Dec. 31, 2018	Sep. 28, 2018	Jun. 29, 2018	Dec. 31, 2017	Sep. 29, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Income Tax Contingency [Line Items]
Gross Margin Percentage	53.10%	49.80%	52.00%		51.10%	41.10%	48.70%
Unrecognized Tax Benefits, Reduction Resulting from Lapse of Applicable Statute of Limitations								$ 2,400	$ 100	$ 2,200	$ 1,000
Tax Benefits Associated with AMT Tax Refund related to TCJA								$ 2,500
Tax Expense Related to Tax Law Changes in Foreign Subsidiary									2,958	$ 273	$ 2,738
TVN [Member]
Income Tax Contingency [Line Items]
Business Combination, Acquisition and Integration Related Expenses				$ 100	$ 100	$ 500	$ 2,200
Foreign Tax Authority [Member]
Income Tax Contingency [Line Items]
Valuation Allowance, Deferred Tax Asset, Increase (Decrease), Amount	$ 1,000								$ 1,500
Foreign Tax Authority [Member]
Income Tax Contingency [Line Items]
Tax Expense Related to Tax Law Changes in Foreign Subsidiary				$ 3,000