Schedule of Revenues by Country (Detail) - USD ($) $ in Thousands		12 Months Ended
		Dec. 31, 2019		Dec. 31, 2018		Dec. 31, 2017
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenue from unaffiliated customers	[2]	$ 2,294,965	[1]	$ 2,100,802	[1]	$ 2,136,606
CHINA
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenue from unaffiliated customers	[2]	514,327		348,942		260,451
TAIWAN
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenue from unaffiliated customers	[2]	485,681		516,322		687,031
UNITED STATES
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenue from unaffiliated customers	[2]	333,059		282,869		252,516
KOREA
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenue from unaffiliated customers	[2]	239,504		163,224		206,819
Europe
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenue from unaffiliated customers	[2]	219,015		223,207		163,715
JAPAN
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenue from unaffiliated customers	[2]	175,322		158,281		169,093
THAILAND
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenue from unaffiliated customers	[2]	87,503		59,184		29,566
SINGAPORE
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenue from unaffiliated customers	[2]	84,111		108,618		101,085
MALAYSIA
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenue from unaffiliated customers	[2]	58,200		122,797		124,048
PHILIPPINES
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenue from unaffiliated customers	[2]	54,560		77,996		105,850
Rest Of The World
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenue from unaffiliated customers	[2]	$ 43,683		$ 39,362		$ 36,432

[1] Restructuring and other includes a $5.8 million gain for the decrease in the fair value adjustment to the MiR acquisition contingent consideration, partially offset by a $3.0 million fair value adjustment to increase the AutoGuide acquisition contingent consideration, $0.5 million of employee severance charges and $0.2 million of acquisition related expenses and compensation.

[2] Revenues attributable to a country are based on location of customer site.