Business combination acquisition and integration related costs and amortization of acquired intangibles.

No definition available.

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Balance Type:	debit
Period Type:	duration

- Definition

Business combination escrow amount.

+ References

No definition available.

+ Details

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Balance Type:	debit
Period Type:	duration

- Definition

Business combination potential release of fund from escrow amount.

+ References

No definition available.

+ Details

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Balance Type:	credit
Period Type:	duration

- Definition

With respect to a business combination completed during the period, this element provides a description of the business, other than the name, which may include the industry, size, products and other important information.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=79982066&loc=d3e1392-128463

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- Definition

Date when the acquirer obtains control of the acquiree, in CCYY-MM-DD format.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
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-Section 50
-Paragraph 2
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=79982066&loc=d3e1392-128463

+ Details

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Balance Type:	na
Period Type:	duration

- 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

Name:	us-gaap_BusinessAcquisitionLineItems
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Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

In a business combination in which the amount of net identifiable assets acquired and liabilities assumed exceeds the aggregate consideration transferred or to be transferred (as defined), this element represents the amount of gain recognized by the entity.

+ References

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+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Amount of increase (decrease) in the value of a contingent consideration liability, including, but not limited to, differences arising upon settlement.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (a)
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-Publisher FASB
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Balance Type:	debit
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- Definition

For contingent consideration arrangements recognized in connection with a business combination, this element represents an estimate of the high-end of the potential range (undiscounted) of the consideration which may be paid.

+ References

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-Publisher FASB
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-Paragraph 1
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Period Type:	instant

- Definition

For contingent consideration arrangements and indemnification assets recognized in connection with a business combination, this element represents an estimate of the low-end of the potential range (undiscounted) of the consideration which may be paid.

+ References

+ Details

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- Definition

Amount of liability recognized arising from contingent consideration in a business combination.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 30
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- 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

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-Publisher FASB
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-SubTopic 20
-Section 50
-Paragraph 1
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- Details

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- Details

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Business Combinations - Additional Information (Detail) - USD ($) $ in Thousands			3 Months Ended		12 Months Ended
	Nov. 30, 2018	Mar. 19, 2018	Mar. 31, 2019	Mar. 31, 2018	Dec. 31, 2018
Business Acquisition [Line Items]
Goodwill			$ 7,000		$ 7,100
Bargain purchase gain net of income taxes				$ 11,322
Acquisition and integration related expenses and amortization of acquired intangibles			$ 1,300	200
SmartRG Inc [Member]
Business Acquisition [Line Items]
Date of acquisition			Nov. 30, 2018
Business acquisition, description			On November 30, 2018, we acquired SmartRG, Inc., a provider of carrier-class, open-source connected home platforms and cloud services for broadband service providers in exchange for cash consideration. This transaction was accounted for as a business combination. We have included the financial results of this acquisition in our consolidated financial statements since the date of acquisition. This revenue is included in the Subscriber Solutions & Experience category within the Network Solutions and Services & Support reportable segments.
Business combination, contingent consideration, liability	$ 1,200		$ 1,200
Minimum potential payment under contingent liability	0
Maximum potential payment under contingent liability	1,500
Change in fair value			0
Business combination escrow amount	2,800
Goodwill			$ 3,500
SmartRG Inc [Member] \| Minimum [Member]
Business Acquisition [Line Items]
Business combination potential release of funds	0
SmartRG Inc [Member] \| Maximum [Member]
Business Acquisition [Line Items]
Business combination potential release of funds	$ 2,800
Sumitomo [Member]
Business Acquisition [Line Items]
Date of acquisition			Mar. 19, 2018
Business acquisition, description			On March 19, 2018, we acquired Sumitomo Electric Lightwave Corp.’s (SEL) North American EPON business and entered into a technology license and OEM supply agreement with Sumitomo Electric Industries, Ltd. (SEI).
Bargain purchase gain net of income taxes		$ 11,322		$ 11,300