Schedule of Revenues by Country (Detail) - USD ($) $ in Thousands		12 Months Ended
		Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenue from unaffiliated customers	[1],[2]	$ 3,702,881	$ 3,121,469	$ 2,294,965
CHINA
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenue from unaffiliated customers	[2]	631,963	465,722	514,327
TAIWAN
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenue from unaffiliated customers	[2]	1,117,874	1,178,068	485,681
UNITED STATES
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenue from unaffiliated customers	[2]	392,626	321,674	333,059
KOREA
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenue from unaffiliated customers	[2]	502,167	391,571	239,504
Europe
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenue from unaffiliated customers	[2]	259,954	205,587	219,015
JAPAN
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenue from unaffiliated customers	[2]	166,231	143,983	175,322
THAILAND
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenue from unaffiliated customers	[2]	138,812	138,787	87,503
SINGAPORE
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenue from unaffiliated customers	[2]	121,582	76,460	84,111
MALAYSIA
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenue from unaffiliated customers	[2]	136,774	56,096	58,200
PHILIPPINES
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenue from unaffiliated customers	[2]	166,838	68,887	54,560
Rest Of The World
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenue from unaffiliated customers	[2]	$ 68,060	$ 74,634	$ 43,683

[1] Includes $13.2 million, $10.0 million and $8.4 million in 2021, 2020 and 2019, respectively, for leases of Teradyne’s systems recognized outside of ASC 606: “Revenue from Contracts with Customers.”

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