Revenue Recognition - Additional Information (Detail)	6 Months Ended
Jun. 30, 2018 USD ($) segment channel
Disaggregation Of Revenue [Line Items]
Number of business segments \| segment	3
Number of distribution channels \| channel	3
Revenue, practical expedient, financing component	true
Nondisclosure of revenues allocated to future shipments of partially completed contracts	true
Assurance warranty period, from date of shipment	12 months
Extended product warranty and service description	For certain of its products, the Company will separately sell extended warranty and service policies to its customers. These policies typically are for periods ranging from one to three years.
Deferred revenue recognized	$ 5,200,000
Deferred costs	$ 0
Minimum [Member]
Disaggregation Of Revenue [Line Items]
Extended warranty and service period	1 year
Maximum [Member]
Disaggregation Of Revenue [Line Items]
Extended warranty and service period	3 years

Extended warranty and service period.

No definition available.

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- Definition

Number of distribution channels.

+ References

No definition available.

+ Details

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- Definition

Revenue recognition, assurance warranty period, from date of shipment

+ References

No definition available.

+ Details

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- Definition

Amount of revenue recognized that was previously included in balance of obligation to transfer good or service to customer for which consideration from customer has been received or is due.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 8
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=109196051&loc=SL49130549-203045

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

The carrying amount of deferred costs.

+ References

No definition available.

+ Details

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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.

+ References

No definition available.

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- Definition

Number of operating segments. An operating segment is a component of an enterprise: (a) that engages in business activities from which it may earn revenues and incur expenses (including revenues and expenses relating to transactions with other components of the same enterprise), (b) whose operating results are regularly reviewed by the enterprise's chief operating decision maker to make decisions about resources to be allocated to the segment and assess its performance, and (c) for which discrete financial information is available. An operating segment may engage in business activities for which it has yet to earn revenues, for example, start-up operations may be operating segments before earning revenues.

+ References

No definition available.

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Balance Type:	na
Period Type:	duration

- Definition

Description of warranty and related obligation in contract with customer.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 12
-Subparagraph (e)
-URI http://asc.fasb.org/extlink&oid=109196051&loc=SL49130554-203045

+ Details

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Balance Type:	na
Period Type:	duration

- Definition

Indicates (true false) whether practical expedient was elected not to adjust consideration for effect of financing component when transfer and customer payment for product or service occurs within one year or less.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 22
-URI http://asc.fasb.org/extlink&oid=109196051&loc=SL49130569-203045

+ Details

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- Definition

Indicates (true false) whether practical expedient was elected not to disclose amount of transaction price allocated to remaining performance obligation and explanation of expected timing of revenue recognition for reporting period presented prior to date of initial application under retrospective method.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 65
-Paragraph 1
-Subparagraph (f)(3)
-URI http://asc.fasb.org/extlink&oid=113356391&loc=SL49131195-203048

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