Restructuring and Related Charges Restructuring and Related Charges - Estimated Future Payments (Details) - TVN [Member] - TVN Voluntary Departure Plan [Member] - Harmonic 2016 Restructuring Plan [Member] $ in Thousands	Sep. 29, 2017 USD ($)
Restructuring Cost and Reserve [Line Items]
2017 (remaining three months)	$ 1,145
2018	2,937
2019	1,379
2020	543
Total	$ 6,004