Antidilution adjustments of convertible note hedges.

No definition available.

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- Definition

Available incremental amount under the credit facilitynNot to exceed percentage of consolidated EBIDTA.

+ References

No definition available.

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- Definition

Percentage of issued and outstanding shares acquired.

+ References

No definition available.

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- Definition

Warrant transactions date of expiry.

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No definition available.

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- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

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No definition available.

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Face (par) amount of debt instrument at time of issuance.

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Contractual interest rate for funds borrowed, under the debt agreement.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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- Definition

Weighted average interest rate of debt outstanding.

+ References

No definition available.

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- Definition

The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

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The maximum amount of borrowing capacity under a line of credit that is available as of the balance sheet date for a specific purpose other than for financing goods acquired for inventory or imminent delivery to a customer.

+ References

No definition available.

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Fair value of the amount outstanding under the credit facility.

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Description of interest rate for borrowing under credit facility. Includes, but is not limited to, terms and method for determining interest rate.

+ References

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Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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The fee, expressed as a percentage of the line of credit facility, for available but unused credit capacity under the credit facility.

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No definition available.

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Period between issuance and maturity of long-term debt, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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The cash outflow to reacquire common stock during the period.

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Amount of accumulated undistributed earnings (deficit).

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Equity impact of the value of new stock issued during the period. Includes shares issued in an initial public offering or a secondary public offering.

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Debt - Additional Information (Detail) - USD ($) $ in Thousands, shares in Millions	3 Months Ended	9 Months Ended
	Sep. 29, 2024	Sep. 28, 2025	Sep. 29, 2024	Oct. 30, 2025	Sep. 19, 2025	Sep. 04, 2025	Dec. 31, 2024	May 27, 2024	May 16, 2024	Oct. 05, 2022	May 01, 2020	Dec. 12, 2016
Debt Instrument
Repurchase of common stock		$ 518,658	$ 55,053
Stock issued during period, value	$ 1,200		$ 10,000
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%
Percentage of issued and outstanding shares acquired								10.00%
Retained Earnings (Accumulated Deficit)		$ 686,782					$ 970,761
Warrant [Member]
Debt Instrument
Warrant expired	1.3		14.7
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		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					$ 200,000	$ 200,000			$ 185,000
Percentage of issued and outstanding shares acquired									10.00%
Average interest rate on borrowings					5.29%	5.29%
Credit Agreement \| Subsequent Event
Debt Instrument
Amount outstanding from Credit Facility				$ 250,000