Debt - Additional Information (Detail) - USD ($) shares in Millions	3 Months Ended	6 Months Ended		9 Months Ended
	Jun. 30, 2024	Jun. 29, 2025	Jun. 30, 2024	Sep. 29, 2024	Dec. 31, 2024	May 27, 2024	May 16, 2024	Oct. 05, 2022	May 01, 2020	Dec. 12, 2016
Debt Instrument
Repurchase of common stock		$ 274,873,000	$ 30,306,000
Stock issued during period, value	$ 8,000,000		$ 8,800,000
Line of Credit Facility, Maximum Borrowing Capacity								$ 750,000,000	$ 400,000,000
Line of Credit Facility, Capacity Available for Specific Purpose Other than for Trade Purchases		$ 200,000,000
Line of Credit Facility, Interest Rate Description		The interest rate applicable to loans under the Credit Facility are, at Teradyne’s option, equal to either a base rate plus a margin ranging from 0.00% to 0.75% per annum or SOFR plus a margin ranging from 1.10% to 1.85% per annum, based on the consolidated leverage ratio of Teradyne. In addition, Teradyne will pay a commitment fee on the unused portion of the commitments under the Credit Facility ranging from 0.15% to 0.25% per annum, based on the then applicable consolidated leverage ratio.
Term of revolving credit facility									3 years
Available Incremental Amount Under The Credit Facility Not To Exceed Percentage Of Consolidated EBIDTA		15.00%
Percentage of issued and outstanding shares acquired						10.00%
Retained Earnings (Accumulated Deficit)		$ 834,863,000			$ 970,761,000
Warrant [Member]
Debt Instrument
Warrant expired	11.7		13.4
Collateral Pledged [Member]
Debt Instrument
Line of Credit Facility, Interest Rate Description		65
1.25% Convertible Senior Unsecured Notes Due December 15, 2023
Debt Instrument
Aggregate principal amount										$ 460,000,000
Debt instrument, interest rate, stated percentage										1.25%
1.25% Convertible Senior Unsecured Notes
Debt Instrument
Shares that would be issued upon conversion		1.3
Maximum
Debt Instrument
Repurchase of common stock		$ 1,000,000,000
Maximum \| 1.25% Convertible Senior Unsecured Notes
Debt Instrument
Warrant transactions expiry date		Jul. 10, 2024
Minimum \| 1.25% Convertible Senior Unsecured Notes
Debt Instrument
Warrant transactions expiry date		Mar. 18, 2024
Revolving Credit Facility \| Maximum \| Truist Bank [Member]
Debt Instrument
Commitment fee percentage of unused portion of credit facility		0.25%
Revolving Credit Facility \| Minimum \| Truist Bank [Member]
Debt Instrument
Commitment fee percentage of unused portion of credit facility		0.15%
Revolving Credit Facility \| Base Rate \| Maximum \| Truist Bank [Member]
Debt Instrument
Debt instrument, basis spread on variable rate		1.85%
Revolving Credit Facility \| Base Rate \| Minimum \| Truist Bank [Member]
Debt Instrument
Debt instrument, basis spread on variable rate		0.00%
Revolving Credit Facility \| London Interbank Offered Rate (LIBOR) \| Maximum \| Truist Bank [Member]
Debt Instrument
Debt instrument, basis spread on variable rate		0.75%
Revolving Credit Facility \| London Interbank Offered Rate (LIBOR) \| Minimum \| Truist Bank [Member]
Debt Instrument
Debt instrument, basis spread on variable rate				1.10%
Credit Agreement
Debt Instrument
Borrowed amount		$ 0					$ 185,000,000
Percentage of issued and outstanding shares acquired							10.00%

TERADYNE, INC 10-Q