Summary of Significant Accounting Policies - Additional Information (Detail) $ in Millions	12 Months Ended
Dec. 31, 2019 USD ($) segment	Dec. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)
Significant Accounting Policies [Line Items]
Lessor, Operating Lease, Term of Contract	10 years
Number of operating segments \| segment	2
Original maturity of highly liquid investments included in Cash and cash equivalents	40 months
Foreign currency net gains (losses)	$ (2.0)	$ (5.6)	$ 9.0
Scanners, Warranty period	1 year
Advertising cost	$ 119.1	$ 88.4	$ 70.1
Minimum
Significant Accounting Policies [Line Items]
Estimated useful lives of intangibles	1 year
Maximum
Significant Accounting Policies [Line Items]
Original maturity of highly liquid investments included in Cash and cash equivalents	3 months
Estimated useful lives of intangibles	15 years

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Significant Accounting Policies [Line Items]

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- Definition

Standard Product Warranty Time Period

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- Definition

Amount charged to advertising expense for the period, which are expenses incurred with the objective of increasing revenue for a specified brand, product or product line.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 720
-SubTopic 35
-Section 50
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=6420018&loc=d3e36677-107848

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Useful life of finite-lived intangible assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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- Definition

Amount before tax of foreign currency transaction realized gain (loss) recognized in the income statement.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 830
-SubTopic 20
-Section 45
-Paragraph 1
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Term of lessor's operating lease, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 30
-Section 50
-Paragraph 3
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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.

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