Business Combinations - Details of the Acquired Intangible Assets (Detail) - SmartRG Inc [Member] $ in Thousands	Nov. 30, 2018 USD ($)
Business Acquisition [Line Items]
Total, Value	$ 9,960
Developed Technology [Member]
Business Acquisition [Line Items]
Total, Value	$ 7,400
Life (in years)	7 years
Customer Relationships [Member]
Business Acquisition [Line Items]
Total, Value	$ 1,790
Life (in years)	3 years
Licensing Agreements [Member]
Business Acquisition [Line Items]
Total, Value	$ 560
Trade Name [Member]
Business Acquisition [Line Items]
Total, Value	$ 210
Life (in years)	3 years
Licensing Agreements [Member] \| Minimum [Member]
Business Acquisition [Line Items]
Life (in years)	5 years
Licensing Agreements [Member] \| Maximum [Member]
Business Acquisition [Line Items]
Life (in years)	10 years

Weighted average amortization period of finite-lived intangible assets acquired either individually or as part of a group of assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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- Definition

The amount of identifiable intangible assets recognized as of the acquisition date.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
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