Antidilution adjustments of convertible note hedges.

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

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

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Debt instrument, convertible, maximum threshold percentage.

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Debt instrument issuance costs amortization period.

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Long term debt maturities repayments of principal interest payments in next twelve months.

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Payments for Convertible Note Hedge, Net, Financing Activities

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The portion of the carrying value of long-term convertible debt as of the balance sheet date that is scheduled to be repaid within one year or in the normal operating cycle if longer. Convertible debt is a financial instrument which can be exchanged for a specified amount of another security, typically the entity's common stock, at the option of the issuer or the holder.

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Carrying amount of long-term convertible debt as of the balance sheet date, net of the amount due in the next twelve months or greater than the normal operating cycle, if longer. The debt is convertible into another form of financial instrument, typically the entity's common stock.

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Expiration, mandatory redemption, or due date, in YYYY-MM-DD format, of the financial instrument issued in exchange for the original debt being converted in a noncash or part noncash transaction.

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

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Amount of a favorable spread to a debt holder between the amount of debt being converted and the value of the securities received upon conversion. This is an embedded conversion feature of convertible debt issued that is in-the-money at the commitment date.

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The price per share of the conversion feature embedded in the debt instrument.

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Threshold period of specified consecutive trading days within which common stock price to conversion price of convertible debt instrument must exceed threshold percentage for specified number of trading days to trigger conversion feature.

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Minimum percentage of common stock price to conversion price of convertible debt instruments to determine eligibility of conversion.

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Threshold number of specified trading days that common stock price to conversion price of convertible debt instruments must exceed threshold percentage within a specified consecutive trading period to trigger conversion feature.

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Date the debt agreement requires the first payment to be made, in YYYY-MM-DD format.

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

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

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

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Amount, before allocation of valuation allowance, of deferred tax asset attributable to deductible temporary differences, classified as other.

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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.

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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.

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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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Amount, excluding unamortized premium (discount) and debt issuance cost, of long-term debt. Excludes lease obligation.

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

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As of the reporting date, the carrying amount of noncontrolling interests which are redeemable by the (parent) entity (1) at a fixed or determinable price on a fixed or determinable date, (2) at the option of the holder of the noncontrolling interest, or (3) upon occurrence of an event that is not solely within the control of the (parent) entity. The noncontrolling interest holder's ownership (or holders' ownership) may be in the form of common shares (regardless of class), limited partnership units (regardless of class), non-preferential membership interests, or any other form of common equity regardless of investee entity legal form.

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Debt - Additional Information (Detail) $ / shares in Units, $ in Thousands, shares in Millions		3 Months Ended
	Dec. 12, 2016 USD ($) Day $ / shares shares	Apr. 02, 2023 USD ($) $ / shares shares	Apr. 03, 2022 USD ($)	May 05, 2023 USD ($)	Dec. 31, 2022 USD ($)	Oct. 05, 2022 USD ($)	Jan. 01, 2022 USD ($)	May 01, 2020 USD ($)
Debt Instrument
Repurchase of common stock		$ 93,308	$ 201,465
Trading days measurement period \| Day	5
Debt issuance costs, amortization period		7 years
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
Expected principal interest payments in next 12 months		$ 400
Available Incremental Amount Under The Credit Facility Not To Exceed Percentage Of Consolidated EBIDTA		15.00%
Current debt, Conversion		$ 35,109			$ 50,115
Retained earnings		694,145			$ 725,729
Convertible Common Shares [Member]
Debt Instrument
Mezzanine equity		$ 2,300
Subsequent Event
Debt Instrument
Long-Term Debt				$ 427,200
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	$ 460,000
Debt instrument, interest rate, stated percentage	1.25%
Debt instrument, net proceeds after issuance costs	$ 450,800
Payment for net cost of convertible note hedges net of warrant proceeds	33,000	$ 33,000
Repurchase of common stock	$ 50,100
Repurchase of stock, shares \| shares	2.0
Senior notes maturity date	Dec. 15, 2023
Debt instrument, frequency of periodic payment	payable semiannually in arrears on June 15 and December 15 of each year
Debt instrument, date of first required payment	Mar. 31, 2017
Debt instrument, conversion option expiration date	Sep. 15, 2023
Consecutive trading days measurement period \| Day	5
Debt instrument conversion price \| $ / shares	$ 31.44	$ 31.44
Shares that would be issued upon conversion \| shares		14.6
Strike price per share of warrant \| $ / shares		$ 39.46
Debt instrument, convertible, carrying amount of equity component		$ 100,800
Value of notes converted		$ 120,000
1.25% Convertible Senior Unsecured Notes Due December 15, 2023 \| Conversion option one
Debt Instrument
Trading days measurement period \| Day	20
Consecutive trading days measurement period \| Day	30
Percentage of conversion price	130.00%
1.25% Convertible Senior Unsecured Notes Due December 15, 2023 \| Conversion option two
Debt Instrument
Aggregate principal amount	$ 1,000
Percentage of closing sale price of common stock and conversion rate product	98.00%
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%
Teradyne [Member]
Debt Instrument
Mezzanine equity							$ 100,800
Current debt, Conversion							1,400
Debt							6,600
Retained earnings							94,600
Teradyne [Member] \| Accounting Standards Update 2020-06 [Member]
Debt Instrument
Deferred Tax Assets, Other							1,800
Teradyne [Member] \| Accounting Standards Update 2020-06 [Member] \| Revision of Prior Period, Accounting Standards Update, Adjustment [Member]
Debt Instrument
Mezzanine equity							$ 0