Antidilution adjustments of convertible note hedges.

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Available incremental amount under the credit facility not 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 intereat payments thereafter.

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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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The value of the financial instrument(s) that the original debt is being converted into in a noncash (or part noncash) transaction. "Part noncash" refers to that portion of the transaction not resulting in cash receipts or cash payments in the period.

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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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The amount of the original debt being converted in a noncash (or part noncash) transaction. "Part noncash" refers to that portion of the transaction not resulting in cash receipts or cash payments in the period.

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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 carrying amount of the equity component of convertible debt which may be settled in cash upon conversion.

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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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Amount, after accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

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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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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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The cumulative amount of the reporting entity's undistributed earnings or deficit.

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Balance Type:
Period Type:

Debt - Additional Information (Detail) $ / shares in Units, $ in Thousands, shares in Millions				9 Months Ended
	Nov. 04, 2022 USD ($)	May 01, 2020 USD ($)	Dec. 12, 2016 USD ($) Day $ / shares shares	Oct. 02, 2022 USD ($) $ / shares shares	Oct. 03, 2021 USD ($) shares	Oct. 05, 2022 USD ($)	Jan. 01, 2022 USD ($)	Dec. 31, 2021 USD ($)	Dec. 31, 2020 USD ($)
Debt Instrument
Repurchase of common stock				$ 750,000	$ 406,180
Repurchase of stock, shares \| shares				7.2	3.3
Trading days measurement period \| Day			5
Debt issuance costs, amortization period				7 years
Line of Credit Facility, Maximum Borrowing Capacity		$ 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
Current debt, Conversion				14,596				$ 19,182
Mezzanine equity								1,512
Convertible common shares				52,000
Debt				50,195				89,244
Retained earnings				572,652				736,566
Long Term Debt Maturities Repayments Of Principal Interest Payments In Next Twelve Months				600
Long Term Debt Maturities Repayments Of Principal Intereat Payments Thereafter				$ 300
Available Incremental Amount Under The Credit Facility Not To Exceed Percentage Of Consolidated EBIDTA				15.00%
Convertible Common Shares [Member]
Debt Instrument
Mezzanine equity				$ 14,600
Shares Issued, Stock Options Exercised				1,200
Subsequent Event [Member]
Debt Instrument
Line of Credit Facility, Maximum Borrowing Capacity	$ 0
Subsequent Event [Member] \| Amended Credit Agreement [Member]
Debt Instrument
Line of Credit Facility, Maximum Borrowing Capacity						$ 750,000
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
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			$ 31.47	$ 31.47
Shares that would be issued upon conversion \| shares			14.6
Strike price per share of warrant \| $ / shares				$ 39.5
Debt instrument, convertible, carrying amount of equity component								$ 100,800
Debt issuance fees				$ 200
Value of notes converted				$ 155,200
1.25% Convertible Senior Unsecured Notes Due December 15, 2023 \| Subsequent Event [Member]
Debt Instrument
Debt instrument conversion converted instrument amount	$ 401,800
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%
Teradyne [Member]
Debt Instrument
Current debt, Conversion							$ 1,400
Mezzanine equity							100,800
Debt							6,600
Retained earnings							94,600
Teradyne [Member] \| Accounting Standards Update 2020-06 [Member]
Debt Instrument
Deferred Tax Assets							1,800
Teradyne [Member] \| Accounting Standards Update 2020-06 [Member] \| Revision of Prior Period, Accounting Standards Update, Adjustment [Member]
Debt Instrument
Mezzanine equity							$ 0