Goodwill and Identifiable Intangible Assets - Summary of Acquired Intangible Assets (Detail) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Finite-Lived Intangible Assets [Line Items]
Accumulated Amortization	$ (28,684)	$ (19,235)
Net Carrying Amount	60,581
Gross Carrying Amount	89,265	94,971
Accumulated Amortization	60,581	75,736
Customer relationships
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	73,458	73,875
Accumulated Amortization	(17,025)	(6,800)
Net Carrying Amount	56,433	67,075
Developed technologies
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	7,461	6,683
Accumulated Amortization	(6,446)	(5,411)
Net Carrying Amount	1,015	1,272
Trade name and other
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	8,346	14,413
Accumulated Amortization	(5,213)	(7,024)
Net Carrying Amount	$ 3,133	$ 7,389