Segment Information (Details 4) - USD ($) $ in Thousands		3 Months Ended										12 Months Ended
		Dec. 31, 2018	[1],[2]	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	[3],[4],[5],[6]	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2018		Dec. 31, 2017	Dec. 31, 2016
Revenue, Major Customer [Line Items]
Total sales		$ 1,787,142		$ 1,651,248	$ 1,726,540	$ 1,577,710	$ 1,738,593		$ 1,728,524	$ 1,664,170	$ 1,483,105	$ 6,742,640		$ 6,614,392	$ 6,829,118
Operating Segments | CPE
Revenue, Major Customer [Line Items]
Total sales												3,923,894		4,475,670	4,747,445
Operating Segments | CPE | Broadband
Revenue, Major Customer [Line Items]
Total sales												1,643,152		1,808,600	1,683,491
Operating Segments | CPE | Video
Revenue, Major Customer [Line Items]
Total sales												2,280,742		2,667,070	3,063,954
Operating Segments | Network & Cloud:
Revenue, Major Customer [Line Items]
Total sales												2,156,577		2,094,113	2,111,708
Operating Segments | Network & Cloud: | Networks
Revenue, Major Customer [Line Items]
Total sales												1,850,416		1,747,936	1,789,097
Operating Segments | Network & Cloud: | Software And Services
Revenue, Major Customer [Line Items]
Total sales												306,161		346,177	322,611
Operating Segments | Enterprise Networks
Revenue, Major Customer [Line Items]
Total sales												675,352		45,749	0
Other
Revenue, Major Customer [Line Items]
Total sales	[8]											$ (13,183)	[7]	$ (1,140)	$ (30,035)

[1] For the quarter ended December 31, 2018, the Company recorded a gain on the sale of its Taiwan factory and certain equipment of $13.3 million.

[2] In the fourth quarter, the Company recorded losses of $5.7 million associated with the settlement and partial curtailment of its U.S. and Taiwan pension plans.

[3] During 2017, the Company recorded a foreign currency remeasurement loss of $10.5 million related primarily to a deferred income tax liability, in the United Kingdom. This deferred income tax liability is denominated in GBP. The foreign currency remeasurement gain derives from the remeasurement of the GBP deferred income tax liability to the USD, since the date of the acquisition.

[4] For the quarter ended December 31, 2017, the Company recorded an increase to net sales of $8.1 million, to reverse previous quarters reduction in net sales in connection with Warrants.

[5] In the fourth quarter of 2017, the Company recorded acquisition costs of $61.5 million related to the cash settlement of stock-based awards held by transferring employees.

[6] In the fourth quarter of 2017, the Company recorded partial impairments of goodwill and indefinite-lived tradenames of $51.2 million and $3.8 million, respectively, acquired in our ActiveVideo acquisition and included as part of our Cloud TV reporting unit, of which $19.3 million is attributable to noncontrolling interest.

[7] Adjustments include acquisition accounting impacts related to deferred revenue

[8] Includes adjustments related to acquisition accounting impacts on deferred revenues in 2018 and 2017 and reduction in revenue related to warrants in 2016.