Schedule of Changes in Fair Value of Level 3 Contingent Consideration (Detail) - USD ($) $ in Thousands		3 Months Ended
		Apr. 03, 2022	Apr. 04, 2021
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Balance at beginning of period		$ 0	$ 7,227
Fair value adjustment	[1]	0	(7,227)
Balance at end of period		$ 0	$ 0

[1] (a) In the three months ended April 4, 2021, the fair value of contingent consideration for the earn-outs in connection with the acquisition of AutoGuide was reduced to zero, which resulted in a benefit of $7.2 million, primarily due to a decrease in forecasted revenues and earnings before interest and taxes. As of April 3, 2022, the maximum amount of contingent consideration that could be paid in connection with the acquisition of AutoGuide is $87.7 million. The remaining earn-out period ends on December 31, 2022. The sellers of AutoGuide have filed an arbitration claim against Teradyne related to the earn-out alleging non-compliance with the earn-out obligations. In March 2022, both parties reached an agreement to settle it for $26.7 million.