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Debt - Additional Information (Detail) - USD ($) $ in Thousands, shares in Millions	3 Months Ended
	Mar. 30, 2025	Mar. 31, 2024	Dec. 31, 2024	Oct. 05, 2022	May 01, 2020	Dec. 12, 2016
Debt Instrument
Repurchase of common stock	$ 157,475	$ 22,117
Line of Credit Facility, Maximum Borrowing Capacity				$ 750,000	$ 400,000
Line of Credit Facility, Capacity Available for Specific Purpose Other than for Trade Purchases	$ 200,000
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%
Retained Earnings (Accumulated Deficit)	$ 893,227		$ 970,761
Warrant [Member]
Debt Instrument
Warrant expired		0.8
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
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
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	0.75%
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	1.85%
Revolving Credit Facility \| London Interbank Offered Rate (LIBOR) \| Minimum \| Truist Bank [Member]
Debt Instrument
Debt instrument, basis spread on variable rate	1.10%