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	Jun. 30, 2017 USD ($)
Restructuring Cost and Reserve [Line Items]
2017 (remaining six months)	$ 2,349
2018	3,302
2019	1,651
2020	783
Total	$ 8,085