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Goodwill - Additional Information (Detail) - USD ($) $ in Millions		12 Months Ended
	Nov. 30, 2018	Dec. 31, 2019	Dec. 31, 2018
Goodwill [Line Items]
Goodwill		$ 7.0	$ 7.1
Network Solutions [Member]
Goodwill [Line Items]
Goodwill		6.6	6.7
Services & Support [Member]
Goodwill [Line Items]
Goodwill		0.4	$ 0.4
SmartRG Inc [Member]
Goodwill [Line Items]
Goodwill	$ 3.5
Goodwill, reduced amount relates to acquisition		$ 0.1

X

- Definition

Amount of increase in asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized resulting from a business combination.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=108376223&loc=d3e13816-109267

+ Details

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X

- 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.

+ References

No definition available.

+ Details

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X

- Definition

Amount of increase (decrease) of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=108376223&loc=d3e13816-109267

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X

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X

- Details

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X

- Details

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