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Schedule of Amortizable Intangible Assets (Parenthetical) (Detail) $ in Millions	3 Months Ended
	Mar. 31, 2019 USD ($)
Lemsys [Member]
Finite-Lived Intangible Assets
Intangible assets acquired	$ 5.5

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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

Amount of increase in assets, excluding financial assets, lacking physical substance with a definite life, from an acquisition.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 50
-Paragraph 1
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16265-109275

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