Restructuring and Excess Facilities Restructuring and Excess Facilities - 2013 Restructuring Activities (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 2013 Restructuring [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring charges		924	2,168
Adjustments to restructuring provisions		(17)	77
Payments for Restructuring		(1,086)	(1,513)
Restructuring Reserve, Settled without Cash			(553)
Restructuring Reserve		0	179
Severance [Member] \| Harmonic 2013 Restructuring [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring charges		829	1,663
Adjustments to restructuring provisions		(17)	29
Payments for Restructuring		(991)	(1,513)
Restructuring Reserve, Settled without Cash			0
Restructuring Reserve		0	179
Impairment of Leasehold Improvements \| Harmonic 2013 Restructuring [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring charges		0	101
Adjustments to restructuring provisions		0	48
Payments for Restructuring		0	0
Restructuring Reserve, Settled without Cash			(149)
Restructuring Reserve		0	0
Obsolete Inventories \| Harmonic 2013 Restructuring [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring charges		0	404
Adjustments to restructuring provisions		0	0
Payments for Restructuring		0	0
Restructuring Reserve, Settled without Cash			(404)
Restructuring Reserve		0	0
Termination of a Research and Development Project \| Harmonic 2013 Restructuring [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring charges		63	0
Adjustments to restructuring provisions		0	0
Payments for Restructuring		(63)	0
Restructuring Reserve, Settled without Cash			0
Restructuring Reserve		0	0
Excess Facilities [Member] \| Harmonic 2013 Restructuring [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring charges		32	0
Adjustments to restructuring provisions		0	0
Payments for Restructuring		(32)	0
Restructuring Reserve, Settled without Cash			0
Restructuring Reserve		$ 0	$ 0

Amount of expenses associated with exit or disposal activities pursuant to an authorized plan. Includes, but is not limited to, one-time termination benefits, termination of an operating lease or other contract, consolidating or closing facilities, and relocating employees, and termination benefits associated with an ongoing benefit arrangement. Excludes expenses associated with special or contractual termination benefits, a discontinued operation or an asset retirement obligation.

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-Publisher FASB
-Name Accounting Standards Codification
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Amount of cash payments made as the result of exit or disposal activities. Excludes payments associated with a discontinued operation or an asset retirement obligation.

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Carrying amount (including both current and noncurrent portions of the accrual) as of the balance sheet date pertaining to a specified type of cost associated with exit from or disposal of business activities or restructuring pursuant to a duly authorized plan.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Amount of expense (reversal of expense) which increases (decreases) the restructuring reserve from an adjustment to a previously accrued restructuring liability.

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Amount of decrease in the reserve for full or partial settlement through consideration other than cash.

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