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Legal Proceedings - Additional Information (Detail) $ in Millions		3 Months Ended		12 Months Ended
	Oct. 24, 2017 USD ($)	Sep. 25, 2020 USD ($)	Jun. 28, 2019 USD ($)	Dec. 31, 2017 USD ($)	Oct. 19, 2017 USD ($)	Jun. 29, 2012 Patents	Oct. 31, 2011 Patents
Avid [Member]
Loss Contingencies [Line Items]
Estimated Litigation Liability					$ 6.0
Payments for Legal Settlements	$ 2.5
Settled Litigation Payment Second Quarter of 2019 [Member] \| Avid [Member]
Loss Contingencies [Line Items]
Payments for Legal Settlements			$ 1.5
Settled Litigation Payment Third Quarter of 2020 [Member] \| Avid [Member]
Loss Contingencies [Line Items]
Payments for Legal Settlements		$ 2.0
Media grid [Member] \| Avid Technology Inc. [Member]
Loss Contingencies [Line Items]
Infringements of number of patents held \| Patents							2
Spectrum [Member] \| Avid Technology Inc. [Member]
Loss Contingencies [Line Items]
Infringements of number of patents held \| Patents						1
Selling, General and Administrative Expenses [Member] \| Avid [Member]
Loss Contingencies [Line Items]
Litigation Settlement, Expense				$ 6.0