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v3.22.1

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 |  |  |

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