Goodwill and Intangible Assets, Net - Acquisition-Related Intangible Assets (Detail) - USD ($) $ in Thousands	Jun. 30, 2019	Dec. 31, 2018
Finite Lived Intangible Assets [Line Items]
Gross Carrying Value	$ 490,687	$ 310,590
Accumulated Amortization	(220,764)	(191,990)
Net Book Value	269,923	118,600
Developed Technology [Member]
Finite Lived Intangible Assets [Line Items]
Gross Carrying Value	417,739	263,720
Accumulated Amortization	(197,675)	(167,664)
Net Book Value	220,064	96,056
Trademarks, Branding and Domain Names [Member]
Finite Lived Intangible Assets [Line Items]
Gross Carrying Value	64,558	32,772
Accumulated Amortization	(15,199)	(11,702)
Net Book Value	49,359	21,070
Noncompetition Agreements [Member]
Finite Lived Intangible Assets [Line Items]
Gross Carrying Value	8,390	8,390
Accumulated Amortization	(7,890)	(7,107)
Net Book Value	$ 500	1,283
Acquired Lease Intangibles [Member]
Finite Lived Intangible Assets [Line Items]
Gross Carrying Value		5,708
Accumulated Amortization		(5,517)
Net Book Value		$ 191

Accumulated amount of amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 50
-Paragraph 2
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16323-109275

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Amount before amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 928
-SubTopic 340
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6473545&loc=d3e61844-108004

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