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v3.25.2

Debt - Additional Information (Detail) - USD ($) shares in Millions | 3 Months Ended | 6 Months Ended | 9 Months Ended |  |  |  |  |  |
--- | --- | --- | --- | --- | --- | --- | --- | --- | ---
Jun. 30, 2024 | Jun. 29, 2025 | Jun. 30, 2024 | Sep. 29, 2024 | Dec. 31, 2024 | May 27, 2024 | May 16, 2024 | Oct. 05, 2022 | May 01, 2020 | Dec. 12, 2016
Debt Instrument |  |  |  |  |  |  |  |  |  |
Repurchase of common stock |  | $ 274,873,000 | $ 30,306,000 |  |  |  |  |  |  |
Stock issued during period, value | $ 8,000,000 |  | $ 8,800,000 |  |  |  |  |  |  |
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 |  |  |  |  |  |  |  |
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) |  | $ 834,863,000 |  |  | $ 970,761,000 |  |  |  |  |
Warrant [Member] |  |  |  |  |  |  |  |  |  |
Debt Instrument |  |  |  |  |  |  |  |  |  |
Warrant expired | 11.7 |  | 13.4 |  |  |  |  |  |  |
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%
1.25% Convertible Senior Unsecured Notes |  |  |  |  |  |  |  |  |  |
Debt Instrument |  |  |  |  |  |  |  |  |  |
Shares that would be issued upon conversion |  | 1.3 |  |  |  |  |  |  |  |
Maximum |  |  |  |  |  |  |  |  |  |
Debt Instrument |  |  |  |  |  |  |  |  |  |
Repurchase of common stock |  | $ 1,000,000,000 |  |  |  |  |  |  |  |
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 |  | 1.85% |  |  |  |  |  |  |  |
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 |  | 0.75% |  |  |  |  |  |  |  |
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 |  |  |  |  | $ 185,000,000 |  |  |
Percentage of issued and outstanding shares acquired |  |  |  |  |  |  | 10.00% |  |  |

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