Summary of Gross Carrying Amount and Accumulated Amortization for Intangible Assets Resulting from Acquisitions (Detail) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2019	Dec. 31, 2018
Acquired Finite Lived Intangible Assets [Line Items]
Gross carrying amount	$ 25,609	$ 23,939
Accumulated amortization	(14,887)	(12,959)
Intangible assets, net	$ 10,722	10,980
Trademarks
Acquired Finite Lived Intangible Assets [Line Items]
Amortization period (in years)	5 years
Gross carrying amount	$ 758	600
Accumulated amortization	(191)	(77)
Intangible assets, net	567	523
Developed Technology
Acquired Finite Lived Intangible Assets [Line Items]
Gross carrying amount	9,099	8,300
Accumulated amortization	(4,650)	(3,978)
Intangible assets, net	$ 4,449	4,322
Developed Technology | Minimum
Acquired Finite Lived Intangible Assets [Line Items]
Amortization period (in years)	10 years
Developed Technology | Maximum
Acquired Finite Lived Intangible Assets [Line Items]
Amortization period (in years)	12 years
Customer Relationships
Acquired Finite Lived Intangible Assets [Line Items]
Gross carrying amount	$ 15,752	15,039
Accumulated amortization	(10,046)	(8,904)
Intangible assets, net	$ 5,706	$ 6,135
Customer Relationships | Minimum
Acquired Finite Lived Intangible Assets [Line Items]
Amortization period (in years)	4 years
Customer Relationships | Maximum
Acquired Finite Lived Intangible Assets [Line Items]
Amortization period (in years)	12 years