Interest Expense on Teradyne's Senior Notes (Detail) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2024	Jul. 02, 2023	Jun. 30, 2024	Jul. 02, 2023
Debt Instrument
Contractual interest expense on the coupon	$ 0	$ 100	$ 0	$ 238
Amortization of debt issuance fees recognized as interest expense	0	0	0	113
Total interest expense on the convertible debt	$ 0	$ 100	$ 0	$ 351