Restructuring and Excess Facilities Restructuring and Excess Facilities - 2016 Restructuring Roll Forward (Details) - USD ($) $ in Thousands		12 Months Ended
		Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Restructuring Cost and Reserve [Line Items]
Adjustments to restructuring provisions		$ 14,602	$ 1,372	$ 2,761
Harmonic 2016 Restructuring Plan [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring charges		19,779
Adjustments to restructuring provisions		247
Reclassification of deferred rent		1,087
Cash payments		(7,507)
Foreign exchange loss		(62)
Restructuring reserve		13,544
Less: current portion (4)	[1]	(9,201)
Long-term portion (4)	[1]	4,343
Facility Closing [Member] | Harmonic 2016 Restructuring Plan [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring charges	[2]	1,655
Adjustments to restructuring provisions	[2]	582
Reclassification of deferred rent	[2]	1,087
Cash payments	[2]	(948)
Foreign exchange loss	[2]	(1)
Restructuring reserve	[2]	2,375
Less: current portion (4)	[1],[2]	(1,085)
Long-term portion (4)	[1],[2]	1,290
TVN Voluntary Departure Plan [Member] | Harmonic 2016 Restructuring Plan [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring charges	[3]	13,175
Adjustments to restructuring provisions	[3]	0
Reclassification of deferred rent	[3]	0
Cash payments	[3]	(3,484)
Foreign exchange loss	[3]	(41)
Restructuring reserve	[2]	9,650
Less: current portion (4)	[1],[3]	(6,597)
Long-term portion (4)	[1],[3]	3,053
Employee Severance [Member] | Harmonic 2016 Restructuring Plan [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring charges	[4]	4,702
Adjustments to restructuring provisions	[4]	(88)
Reclassification of deferred rent	[4]	0
Cash payments	[4]	(3,075)
Foreign exchange loss	[4]	(20)
Restructuring reserve	[4]	1,519
Less: current portion (4)	[1],[4]	(1,519)
Long-term portion (4)	[1],[4]	0
Other Restructuring [Member] | Harmonic 2016 Restructuring Plan [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring charges		247
Adjustments to restructuring provisions		$ (247)

[1] The current portion and long-term portion of the restructuring liability are reported under “Accrued and other current liabilities” and “Other non-current liabilities”, respectively, on the Company’s Consolidated Balance Sheets.

[2] In December 2016, the Company also exited from an excess facility at its office in Paris, France and recorded $0.2 million of facility exit costs. This liability will be fully paid in the first quarter of 2017.

[3] See discussion on TVN VDP above for future estimated payments under the TVN VDP through 2020.

[4] The Company anticipates that the remaining severance and benefits (non-TVN VDP related) accrual at December 31, 2016 will be fully paid by the first quarter of 2017.