Acquisitions and Disposals - Summary of Amounts of Identified Assets Acquired and Liabilities Assumed at the Acquisition Date (Parenthetical) (Detail) - Datawatch Corporation [Member] $ in Millions	9 Months Ended
Sep. 30, 2019 USD ($)
Software [Member]
Business Acquisition [Line Items]
Goodwill deductible for tax purposes	$ 0.8
Developed Technology [Member]
Business Acquisition [Line Items]
Weighted-average useful life of acquired finite-lived intangible assets	6 years
Customer Relationships [Member]
Business Acquisition [Line Items]
Weighted-average useful life of acquired finite-lived intangible assets	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.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 50
-Paragraph 1
-Subparagraph (a)(3)
-URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16265-109275

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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

The amount of goodwill arising from a business combination that is expected to be deductible for tax purposes.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 50
-Paragraph 1
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=35744584&loc=d3e6927-128479

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