Antidilution adjustments of convertible note hedges.

No definition available.

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Balance Type:	na
Period Type:	duration

- Definition

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

+ References

No definition available.

+ Details

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- Definition

Class of warrant or right exercise price of warrants or rights issued.

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No definition available.

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- Definition

Payments for Convertible Note Hedge, Net, Financing Activities

+ 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.

+ References

No definition available.

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- Definition

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

+ References

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Description of the frequency of periodic payments (monthly, quarterly, annual).

+ References

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- Definition

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

+ References

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- Definition

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

Date when the debt instrument is scheduled to be fully repaid, in YYYY-MM-DD format.

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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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Period Type:	instant

- Definition

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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Period Type:	instant

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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.

+ References

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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.

+ References

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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- Definition

The cash outflow to reacquire common stock during the period.

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- Definition

The cash inflow from additional borrowings, net of cash paid to third parties in connection with debt origination.

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- Definition

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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- Definition

Number of shares that have been repurchased and retired during the period.

+ References

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- Definition

Number of shares that have been repurchased during the period and have not been retired and are not held in treasury. Some state laws may govern the circumstances under which an entity may acquire its own stock and prescribe the accounting treatment therefore. This element is used when state law does not recognize treasury stock.

+ References

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Debt - Additional Information (Detail) - USD ($) $ / shares in Units, shares in Millions		3 Months Ended	9 Months Ended
	Dec. 12, 2016	Sep. 29, 2024	Sep. 29, 2024	Oct. 01, 2023	May 27, 2024	May 16, 2024	Dec. 31, 2023	Oct. 05, 2022	May 01, 2020
Debt Instrument
Repurchase of common stock			$ 55,053,000	$ 346,492,000
Stock issued during period, value		$ 1,200,000	10,000,000
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	$ 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)		$ 990,039,000	$ 990,039,000				$ 706,514,000
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	$ 460,000,000
Debt instrument, interest rate, stated percentage	1.25%
Debt instrument, net proceeds after issuance costs	$ 450,800,000
Payment for net cost of convertible note hedges net of warrant proceeds	33,000,000
Repurchase of common stock	$ 50,100,000
Repurchase of stock, shares	2.0
Debt instrument, frequency of periodic payment	payable semiannually in arrears on June 15 and December 15 of each year
1.25% Convertible Senior Unsecured Notes
Debt Instrument
Senior notes maturity date	Dec. 15, 2023
Shares that would be issued upon conversion			1.3
Strike price per share of warrant			$ 39.35
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%
Credit Agreement
Debt Instrument
Borrowed amount		$ 0	$ 0			$ 185,000,000
Percentage of issued and outstanding shares acquired						10.00%