Intangible Assets - Summary of Intangible Assets (Detail) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Finite-Lived Intangible Assets [Line Items]
Intangible asset, Gross amount	$ 25,291	$ 25,392
Accumulated amortization	(22,414)	(22,623)
Intangible asset, Net amount	2,877	2,769
Technology [Member]
Finite-Lived Intangible Assets [Line Items]
Intangible asset, Gross amount	6,487	6,575
Accumulated amortization	(6,487)	(6,575)
Customer Relationships [Member]
Finite-Lived Intangible Assets [Line Items]
Intangible asset, Gross amount	10,044	10,180
Accumulated amortization	(10,044)	(10,180)
Intellectual Property Assets [Member]
Finite-Lived Intangible Assets [Line Items]
Intangible asset, Gross amount	8,760	8,637
Accumulated amortization	(5,883)	(5,868)
Intangible asset, Net amount	$ 2,877	$ 2,769