Segment Information - Reconciliation of Segment Operating Income to Consolidated Income Before Income Taxes (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018		Dec. 31, 2017
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Unallocated corporate expenses	$ (209,929)	$ (214,220)		$ (240,697)
Stock-based compensation expense	(12,074)	(17,289)		(16,610)	[1]
Amortization	(8,319)	(8,367)		(8,322)	[1]
Operating Income (Loss)	13,083	(5,011)		(70,877)	[1]
Gain (Loss) on Extinguishment of Debt	(5,695)	0		0
Non-operating expense, net	(13,984)	(11,937)		(13,830)	[1]
Loss before income taxes	(6,596)	(16,948)		(84,707)	[1]
Operating Segments [Member]
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Operating Income (Loss)	38,008	24,414	[2]	(25,178)	[1]
Corporate, Non-Segment [Member]
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Unallocated corporate expenses	$ (4,532)	$ (3,769)		$ (20,767)	[1]

[1] For the year ended December 31, 2017, the unallocated corporate expenses included acquisition- and integration-related costs, French VDP costs (see Note 11, “Restructuring and Related charges,” for more information on French VDP) and Cable Access product line inventory obsolescence costs, totaling $7.9 million. In addition, in fiscal 2017, the unallocated corporate expenses included $8.0 million of Avid litigation settlement cost and associated legal fees (see Note 20, “Legal Proceedings,” for more information). The remaining unallocated corporate expenses for all years presented above include primarily other restructuring charges and excess facilities charges.

[2] The Company has historically employed an aggregate allocation methodology based on total revenues to attribute professional services revenue and sales expenses between its Video and Cable Access segments. Beginning in the fourth quarter of 2017, the Company prospectively changed to a more precise attribution methodology as the activities of selling and supporting the CableOS solution have become increasingly distinct from those of Video solutions. The impact of making this change for the fiscal year ended December 31, 2017 compared to the Company’s historical approach was an increase in operating loss of $5.9 million from the Video segment and a corresponding decrease in operating loss of the Cable Access segment. The Company believes that the updated allocation methodology provides greater clarity regarding the operating metrics of the Video and Cable Access business segments.