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

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Debt - Additional Information (Detail) $ / shares in Units, $ in Thousands				3 Months Ended		9 Months Ended
	May 06, 2022 USD ($)	May 01, 2020 USD ($)	Dec. 12, 2016 USD ($) Day $ / shares shares	Apr. 03, 2022 USD ($) $ / shares shares	Apr. 04, 2021 USD ($) shares	Oct. 03, 2021 USD ($) $ / shares	Dec. 31, 2022 USD ($)	Jan. 01, 2022 USD ($)	Dec. 31, 2021 USD ($)	Dec. 10, 2021 USD ($)	Dec. 31, 2020 USD ($)
Debt Instrument
Repurchase of common stock				$ 201,465	$ 45,188
Repurchase of stock, shares \| shares				1,800,000	400,000
Trading days measurement period \| Day			5
Debt instrument conversion price \| $ / shares				$ 31.51
Shares that would be issued upon conversion \| shares				3.4
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 LIBOR plus a margin ranging from 1.00% to 1.75% 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				$ 20,497					$ 19,182
Mezzanine equity									1,512
Convertible common shares				20,700
Debt				75,378					89,244
Retained earnings				$ 762,189					736,566
Long Term Debt Maturities Repayments Of Principal Interest Payments In Next Twelve Months									1,200
Long Term Debt Maturities Repayments Of Principal Intereat Payments Thereafter							$ 1,200
Available Incremental Amount Under The Credit Facility Not To Exceed Percentage Of Consolidated EBIDTA				15.00%
Convertible Common Shares [Member]
Debt Instrument
Mezzanine equity				$ 20,500
Shares Issued, Stock Options Exercised						$ 500
Subsequent Event [Member]
Debt Instrument
Line of Credit Facility, Maximum Borrowing Capacity	$ 0
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			2,000,000.0
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			$ 31.51	$ 31.51		$ 31.51
Shares that would be issued upon conversion \| shares			14,600,000
Strike price per share of warrant \| $ / shares				$ 39.54
Debt instrument, convertible, carrying amount of equity component									$ 100,800
Debt issuance fees				$ 400
Value of notes converted				$ 355,600
1.25% Convertible Senior Unsecured Notes Due December 15, 2023 \| Subsequent Event [Member]
Debt Instrument
Debt instrument conversion converted instrument amount	$ 373,500
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								99,300
Debt								6,600
Retained earnings								92,800
Teradyne [Member] \| Accounting Standards Update 2020-06 [Member] \| Revision of Prior Period, Accounting Standards Update, Adjustment [Member]
Debt Instrument
Mezzanine equity								$ 0