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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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-Section 50
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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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No definition available.

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Amount of transaction price allocated to performance obligation that has not been recognized as revenue.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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Period in which remaining performance obligation is expected to be recognized as revenue, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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Remaining duration of performance obligation for which optional exemption was applied not to disclose amount of transaction price allocated to and timing of revenue recognition for remaining performance obligation, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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Revenue Narratives (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
Revenue Narratives (Details) - USD ($) $ in Millions	Sep. 27, 2019	Sep. 28, 2018	Sep. 27, 2019	Sep. 28, 2018
Revenue Recognition, Multiple-deliverable Arrangements [Line Items]
Contract with Customer, Liability, Revenue Recognized	$ 6.1	$ 7.8	$ 37.4	$ 43.2
Revenue, Practical Expedient, Initial Application and Transition, Nondisclosure of Transaction Price Allocation to Remaining Performance Obligation [true false]			true
Maximum [Member]
Revenue Recognition, Multiple-deliverable Arrangements [Line Items]
Revenue, Remaining Performance Obligation, Optional Exemption, Remaining Duration	1 year		1 year
Comcast CableOS Software License Agreement [Member]
Revenue Recognition, Multiple-deliverable Arrangements [Line Items]
Revenue, Remaining Performance Obligation, Amount	$ 110.3		$ 110.3
Comcast CableOS Software License Agreement [Member] \| Minimum [Member]
Revenue Recognition, Multiple-deliverable Arrangements [Line Items]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Period	3 years		3 years
Comcast CableOS Software License Agreement [Member] \| Maximum [Member]
Revenue Recognition, Multiple-deliverable Arrangements [Line Items]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Period	4 years		4 years
Support and Maintenance Contracts [Member] \| Maximum [Member]
Revenue Recognition, Multiple-deliverable Arrangements [Line Items]
Revenue, Remaining Performance Obligation, Optional Exemption, Remaining Duration	1 year		1 year