Teradyne (TER) 10-Q 1 Nov 24 2024 Q3 Quarterly report Financial data

Cover Page

Cover Page - shares	9 Months Ended
	Sep. 29, 2024	Oct. 28, 2024
Cover [Abstract]
Amendment Flag	false
Document Type	10-Q
Document Fiscal Year Focus	2024
Entity Central Index Key	0000097210
Document Fiscal Period Focus	Q3
Current Fiscal Year End Date	--12-31
Document Period End Date	Sep. 29, 2024
Entity Registrant Name	TERADYNE, INC.
Entity Filer Category	Large Accelerated Filer
Trading Symbol	TER
Document Quarterly Report	true
Document Transition Report	false
Entity Interactive Data Current	Yes
Entity Current Reporting Status	Yes
Title of 12(b) Security	Common Stock
Security Exchange Name	NASDAQ
Entity File Number	001-06462
Entity Incorporation, State or Country Code	MA
Entity Tax Identification Number	04-2272148
Entity Address, Address Line One	600 Riverpark Drive
Entity Address, City or Town	North Reading
Entity Address, State or Province	MA
Entity Address, Postal Zip Code	01864
City Area Code	978
Local Phone Number	370-2700
Entity Small Business	false
Entity Emerging Growth Company	false
Entity Shell Company	false
Entity Common Stock, Shares Outstanding		162,861,462

CONDENSED CONSOLIDATED BALANCE

CONDENSED CONSOLIDATED BALANCE SHEETS - USD ($) $ in Thousands		Sep. 29, 2024		Dec. 31, 2023
Current assets:
Cash and cash equivalents		$ 510,036		$ 757,571
Marketable securities		41,631		62,154
Accounts receivable, less allowance for credit losses of $1,972 and $1,988 at September 29, 2024 and December 31, 2023, respectively		484,376		422,124
Inventories, net	[1]	297,340		309,974
Prepayments	[2]	489,548		548,970
Other current assets		15,935		37,992
Current assets held for sale		0		23,250
Total current assets		1,838,866		2,162,035
Property, plant and equipment, net		491,704		445,492
Operating lease right-of-use assets, net		70,784		73,417
Marketable securities		125,944		117,434
Deferred tax assets		201,881		175,775
Retirement plans assets		13,114		11,504
Equity method investment		538,351		0
Other assets		48,384		38,580
Acquired intangible assets, net		21,288		35,404
Goodwill		419,412		415,652
Long-term assets held for sale		0		11,531
Total assets		3,769,728	[3]	3,486,824
Current liabilities:
Accounts payable		158,459		180,131
Accrued employees' compensation and withholdings		159,794		191,750
Deferred revenue and customer advances		99,776		99,804
Other accrued liabilities		105,150		114,712
Operating lease liabilities		19,175		17,522
Income taxes payable		52,542		48,653
Current liabilities held for sale		0		7,379
Total current liabilities		594,896		659,951
Retirement plans liabilities		137,735		132,090
Long-term deferred revenue and customer advances		41,135		37,282
Long-term other accrued liabilities		8,373		19,998
Deferred tax liabilities		164		183
Long-term operating lease liabilities		60,287		65,092
Long-term incomes taxes payable		24,596		44,331
Long-term liabilities held for sale		0		2,000
Total liabilities		867,186		960,927
Commitments and contingencies (Note R)
SHAREHOLDERS' EQUITY
Common stock, $0.125 par value, 1,000,000 shares authorized; 162,959 and 152,698 shares issued and outstanding at September 29, 2024, and December 31, 2023, respectively		20,370		19,087
Additional paid-in capital		1,896,161		1,827,274
Accumulated other comprehensive loss		(4,028)		(26,978)
Retained earnings		990,039		706,514
Total shareholders' equity		2,902,542		2,525,897
Total liabilities and shareholders' equity		$ 3,769,728		$ 3,486,824
[1] Inventories, net at December 31, 2023, exclude $ 18.0 million of primarily work-in-process inventories, net classified as assets held for sale. See Note E: "Dispositions" for additional information. Exclude s $ 5.3 million at December 31, 2023 , of contract manufacturer and supplier prepayments, classified as assets held for sale. See Note E: “Dispositions” for additional information. Total assets are attributable to each segment. Corporate assets consist of cash and cash equivalents, marketable securities, and certain other assets.

CONDENSED CONSOLIDATED BALANC_2

CONDENSED CONSOLIDATED BALANCE SHEETS (Parenthetical) - USD ($) shares in Thousands, $ in Thousands	Sep. 29, 2024	Dec. 31, 2023
Statement of Financial Position [Abstract]
Accounts receivable, less allowance for doubtful accounts	$ 1,972	$ 1,988
Common stock, par value	$ 0.125	$ 0.125
Common stock, shares authorized	1,000,000	1,000,000
Common stock, shares issued	162,959	152,698
Common stock, shares outstanding	162,959	152,698

CONDENSED CONSOLIDATED STATEMEN

CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS - USD ($) shares in Thousands, $ in Thousands	3 Months Ended				9 Months Ended
	Sep. 29, 2024		Oct. 01, 2023		Sep. 29, 2024		Oct. 01, 2023
Revenues:
Total revenues	$ 737,298	[1]	$ 703,732	[1]	$ 2,066,996	[2]	$ 2,005,699	[2]
Cost of revenues:
Total cost of revenues (exclusive of acquired intangible assets amortization shown separately below)	300,784		305,441		865,357		848,495
Gross profit	436,514		398,291		1,201,639		1,157,204
Operating expenses:
Selling and administrative	157,649		138,330		461,307		434,979
Engineering and development	117,474		104,413		332,489		315,881
Acquired intangible assets amortization	4,748		4,720		14,108		14,348
Restructuring and other	4,578		6,856		11,018		15,251
Gain on sale of business	0		0		(57,486)		0
Total operating expenses	284,449		254,319		761,436		780,459
Income from operations	152,065		143,972		440,203		376,745
Non-operating (income) expense:
Interest income	(5,076)		(6,873)		(19,658)		(18,486)
Interest expense	808		963		2,998		2,994
Other (income) expense, net	(2,651)		5,602		5,574		6,470
Income before income taxes and equity in net earnings of affiliate	158,984		144,280		451,289		385,767
Income tax provision	12,260		16,164		54,095		54,069
Income before equity in net earnings of affiliate	146,724		128,116		397,194		331,698
Equity in net earnings of affiliate	(1,075)				(1,075)
Net income	$ 145,649		$ 128,116		$ 396,119		$ 331,698
Net income per common share:
Basic	$ 0.89		$ 0.83		$ 2.51		$ 2.14
Diluted	$ 0.89		$ 0.78		$ 2.42		$ 2.01
Weighted average common shares—basic	163,002		153,762		157,951		154,809
Weighted average common shares—diluted	164,253		164,050		163,357		165,037
Product [Member]
Revenues:
Total revenues	$ 612,871		$ 551,982		$ 1,668,181		$ 1,565,776
Cost of revenues:
Total cost of revenues (exclusive of acquired intangible assets amortization shown separately below)	253,129		239,827		704,129		655,502
Service [Member]
Revenues:
Total revenues	124,427		151,750		398,815		439,923
Cost of revenues:
Total cost of revenues (exclusive of acquired intangible assets amortization shown separately below)	$ 47,655		$ 65,614		$ 161,228		$ 192,993
[1] Include s $ 0.8 million and $ 1.4 million in 2024, and 2023, respectively, for leases of Teradyne’s systems recognized outside Accounting Standards Codification (“ASC”) 606 “Revenue from Contracts with Customers.” Includes $ 2.5 million and $ 3.9 million in 2024 and 2023, respectively, for leases of Teradyne’s systems recognized outside Accounting Standards Codification (“ASC”) 606 “Revenue from Contracts with Customers.”

CONDENSED CONSOLIDATED STATEM_2

CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 29, 2024	Oct. 01, 2023	Sep. 29, 2024	Oct. 01, 2023
Statement of Comprehensive Income [Abstract]
Net income	$ 145,649	$ 128,116	$ 396,119	$ 331,698
Other comprehensive income (loss), net of tax:
Foreign currency translation adjustment, net of tax of $0, $0, $0, and $0, respectively	37,838	(14,325)	22,751	(2,073)
Available-for-sale marketable securities:
Unrealized (losses) gains on marketable securities arising during period, net of tax of $609, $(731), $205, and $(408), respectively	2,507	(2,628)	885	(903)
Less: Reclassification adjustment for (gains) losses included in net income, net of tax of $(2), $0, $24, and $9, respectively	(7)	0	86	33
Other Comprehensive Income (Loss), Available-for-sale Securities Adjustment, Net of Tax, Total	2,500	(2,628)	971	(870)
Cash flow hedges:
Unrealized (losses) gains arising during period, net of tax of $(73), $728, $285, and $1,816, respectively	(260)	2,590	1,014	6,456
Less: Reclassification adjustment for (gains) losses included in net income, net of tax of $0, $(869), $(500) and $(441) respectively	0	(3,091)	(1,780)	(1,567)
Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), after Reclassification and Tax, Parent	(260)	(501)	(766)	4,889
Defined benefit post-retirement plan:
Amortization of prior service credit, net of tax of $0, $0, $(1), and $(1), respectively	(2)	(2)	(6)	(6)
Other comprehensive income (loss)	40,076	(17,456)	22,950	1,940
Comprehensive income	$ 185,725	$ 110,660	$ 419,069	$ 333,638

CONDENSED CONSOLIDATED STATEM_3

CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (Parenthetical) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 29, 2024	Oct. 01, 2023	Sep. 29, 2024	Oct. 01, 2023
Statement of Comprehensive Income [Abstract]
Foreign currency translation adjustments, tax	$ 0	$ 0	$ 0	$ 0
Unrealized gains (losses) on marketable securities arising during period, net of tax	609	(731)	205	(408)
Reclassification adjustment for losses (gains) included in net income, net of tax	(2)	0	24	9
Amortization of prior service credit, net of tax	0	0	(1)	(1)
Cash flow hedges Unrealized gains	(73)	728	285	1,816
Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), Reclassification, Tax	$ 0	$ (869)	$ (500)	$ (441)

CONDENSED CONSOLIDATED STATEM_4

CONDENSED CONSOLIDATED STATEMENTS OF SHAREHOLDERS' EQUITY - USD ($) $ in Thousands	Total	Common Stock	Additional Paid-in Capital	Accumulated Other Comprehensive Income (Loss)	Retained Earnings
Balance at Dec. 31, 2022	$ 2,451,294	$ 19,470	$ 1,755,963	$ (49,868)	$ 725,729
Balance, Shares at Dec. 31, 2022		155,759,000
Net issuance of common stock under stock-based plans	13,503	$ 104	13,399
Net issuance of common stock under stock-based plans (in shares)		838,000
Stock-based compensation expense	46,775		46,775
Repurchase of common stock	(352,791)	$ (420)			(352,371)
Repurchase of common stock (in shares)		(3,362,000)
Cash dividends	(51,119)				(51,119)
Settlements of convertible notes		$ 72	(72)
Settlements of convertible notes (in shares)		585,000
Exercise of convertible notes hedge call options		$ (72)	72
Exercise of convertible notes hedge call options (in shares)		(585,000)
Net income	331,698				331,698
Other comprehensive income (loss)	1,940			1,940
Balance at Oct. 01, 2023	2,441,300	$ 19,154	1,816,137	(47,928)	653,937
Balance, Shares at Oct. 01, 2023		153,235,000
Balance at Jul. 02, 2023	2,434,883	$ 19,269	1,784,590	(30,472)	661,496
Balance, Shares at Jul. 02, 2023		154,148,000
Net issuance of common stock under stock-based plans	17,206	$ 26	17,180
Net issuance of common stock under stock-based plans (in shares)		207,000
Stock-based compensation expense	14,367		14,367
Repurchase of common stock	(118,907)	$ (141)			(118,766)
Repurchase of common stock (in shares)		(1,120,000)
Cash dividends	(16,909)				(16,909)
Settlements of convertible notes	0	$ 25	(25)
Settlements of convertible notes (in shares)		210,000
Exercise of convertible notes hedge call options	0	$ (25)	25
Exercise of convertible notes hedge call options (in shares)		(210,000)
Net income	128,116				128,116
Other comprehensive income (loss)	(17,456)			(17,456)
Balance at Oct. 01, 2023	2,441,300	$ 19,154	1,816,137	(47,928)	653,937
Balance, Shares at Oct. 01, 2023		153,235,000
Balance at Dec. 31, 2023	2,525,897	$ 19,087	1,827,274	(26,978)	706,514
Balance, Shares at Dec. 31, 2023		152,698,000
Net issuance of common stock under stock-based plans	23,431	$ 91	23,340
Net issuance of common stock under stock-based plans (in shares)		720,000
Stock-based compensation expense	46,817		46,817
Warrant exercises	(16)	$ 1,254	(1,270)
Warrant exercises (in shares)		10,036,000
Repurchase of common stock	(55,692)	$ (62)			(55,630)
Repurchase of common stock (in shares)		(495,000)
Cash dividends	(56,964)				(56,964)
Net income	396,119				396,119
Other comprehensive income (loss)	22,950			22,950
Balance at Sep. 29, 2024	2,902,542	$ 20,370	1,896,161	(4,028)	990,039
Balance, Shares at Sep. 29, 2024		162,959,000
Balance at Jun. 30, 2024	2,730,812	$ 20,225	1,865,351	(44,104)	889,340
Balance, Shares at Jun. 30, 2024		161,802,000
Net issuance of common stock under stock-based plans	14,983	$ 17	14,966
Net issuance of common stock under stock-based plans (in shares)		130,000
Stock-based compensation expense	15,999		15,999
Warrant exercises	(2)	$ 153	(155)
Warrant exercises (in shares)		1,223,000
Repurchase of common stock	(25,401)	$ (25)			(25,376)
Repurchase of common stock (in shares)		(196,000)
Cash dividends	(19,574)				(19,574)
Net income	145,649				145,649
Other comprehensive income (loss)	40,076			40,076
Balance at Sep. 29, 2024	$ 2,902,542	$ 20,370	$ 1,896,161	$ (4,028)	$ 990,039
Balance, Shares at Sep. 29, 2024		162,959,000

CONDENSED CONSOLIDATED STATEM_5

CONDENSED CONSOLIDATED STATEMENTS OF SHAREHOLDERS' EQUITY (Parenthetical) - $ / shares	3 Months Ended		9 Months Ended
	Sep. 29, 2024	Oct. 01, 2023	Sep. 29, 2024	Oct. 01, 2023
Statement of Stockholders' Equity [Abstract]
Common Stock, Dividends, Per Share, Cash Paid	$ 0.12	$ 0.11	$ 0.36	$ 0.33

CONDENSED CONSOLIDATED STATEM_6

CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	9 Months Ended
	Sep. 29, 2024	Oct. 01, 2023
Cash flows from operating activities:
Net income	$ 396,119	$ 331,698
Adjustments to reconcile net income from operations to net cash provided by operating activities:
Depreciation	74,480	68,858
Stock-based compensation	45,267	45,236
Provision for excess and obsolete inventory	15,516	23,069
Amortization	14,133	14,083
Losses (gains) on investments	10,139	(3,159)
Equity in net earnings of affiliate	1,075
Gain on sale of business	(57,486)	0
Deferred taxes	(26,261)	(24,026)
Retirement plan actuarial losses (gains)	(2,512)	0
Other	(5,041)	(13)
Changes in operating assets and liabilities
Accounts receivable	(65,266)	30,191
Inventories	11,127	6,395
Prepayments and other assets	61,438	(63,982)
Accounts payable and other liabilities	(63,666)	3,999
Deferred revenue and customer advances	3,624	(49,517)
Retirement plans contributions	(4,169)	(3,698)
Income taxes	(18,898)	(42,683)
Net cash provided by operating activities	389,619	336,451
Cash flows from investing activities:
Purchases of property, plant and equipment	(140,710)	(115,306)
Purchase of investment in a business	(527,060)	0
Purchases of marketable securities	(35,097)	(137,786)
Issuance of convertible loan		(5,000)
Proceeds from the sale of a business, net of cash and cash equivalents sold	90,348	0
Proceeds from maturities of marketable securities	33,163	71,447
Proceeds from sales of marketable securities	23,600	36,963
Proceeds from insurance	873	460
Net cash used for investing activities	(554,883)	(149,222)
Cash flows from financing activities:
Repayments of borrowings on revolving credit facility	(185,000)	0
Dividend payments	(56,936)	(51,081)
Repurchase of common stock	(55,053)	(346,492)
Payments related to net settlement of employee stock compensation awards	(13,833)	(20,586)
Payments of convertible debt principal	0	(26,735)
Proceeds from borrowings on revolving credit facility	185,000	0
Issuance of common stock under stock purchase and stock option plans	37,265	34,084
Net cash used for financing activities	(88,557)	(410,810)
Effects of exchange rate changes on cash and cash equivalents	6,286	5,769
Decrease in cash and cash equivalents	(247,535)	(217,812)
Cash and cash equivalents at beginning of period	757,571	854,773
Cash and cash equivalents at end of period	510,036	636,961
Non-cash investing activities:
Capital expenditures incurred but not yet paid:	$ 3,679	$ 2,392

Pay vs Performance Disclosure

Pay vs Performance Disclosure - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 29, 2024	Oct. 01, 2023	Sep. 29, 2024	Oct. 01, 2023
Pay vs Performance Disclosure
Net Income (Loss)	$ 145,649	$ 128,116	$ 396,119	$ 331,698

Insider Trading Arrangements

Insider Trading Arrangements - Ryan Driscoll	3 Months Ended
	Sep. 29, 2024 shares
Trading Arrangements, by Individual
Name	Ryan Driscoll
Title	Vice President, General Counsel, and Secretary
Rule 10b5-1 Arrangement Adopted	true
Adoption Date	August 8, 2024
Rule 10b5-1 Arrangement Terminated	true
Termination Date	August 1, 2025
Aggregate Available	365

The Company

The Company	9 Months Ended
	Sep. 29, 2024
The Company	A. THE COMPANY Teradyne, Inc. (“Teradyne”) is a leading global supplier of automated test equipment and robotics solutions. Teradyne designs, develops, manufactures, and sells automated test systems and robotics products. Teradyne’s automated test systems are used to test semiconductors, wireless products, data storage and complex electronics systems in many industries including consumer electronics, wireless, automotive, industrial, computing, communications, and aerospace and defense industries. Teradyne’s robotics products include collaborative robotic arms, autonomous mobile robots, and advanced robotic control software used by global manufacturing, logistics and industrial customers to improve quality, increase manufacturing and material handling efficiency, and decrease manufacturing and logistics costs. Teradyne’s automated test equipment and robotics products and services include: • semiconductor test (“Semiconductor Test”) systems; • storage and system level test (“Integrated System Test” formerly "Storage Test") systems, defense/aerospace (“Defense/Aerospace”) test instrumentation and systems, and circuit-board test and inspection (“Production Board Test”) systems (collectively these products represent “System Test”); • wireless test (“Wireless Test”) systems; and • robotics (“Robotics”) products.

Accounting Policies

Accounting Policies	9 Months Ended
	Sep. 29, 2024
Accounting Policies	B. ACCOUNTING POLICIES Basis of Presentation The consolidated interim financial statements include the accounts of Teradyne and its wholly owned subsidiaries. All significant intercompany balances and transactions have been eliminated. These interim financial statements are unaudited and reflect all normal recurring adjustments that are, in the opinion of management, necessary for the fair statement of such interim financial statements. The December 31, 2023, condensed consolidated balance sheet data was derived from audited financial statements but does not include all disclosures required by United States of America generally accepted accounting principles (“U.S. GAAP”) for complete financial statements. The accompanying financial information should be read in conjunction with the consolidated financial statements and notes thereto contained in Teradyne’s Annual Report on Form 10-K, filed with the U.S. Securities and Exchange Commission (“SEC”) on February 22, 2024, for the year ended December 31, 2023 . Preparation of Financial Statements and Use of Estimates The preparation of consolidated financial statements requires management to make estimates and judgments that affect the reported amounts of assets, liabilities, revenues and expenses, and related disclosure of contingent liabilities. On an on-going basis, management evaluates its estimates, including those related to inventories, investments, goodwill, intangible and other long-lived assets, accounts receivable, income taxes, deferred tax assets and liabilities, pensions, warranties, contingent consideration liabilities, and loss contingencies. Management bases its estimates on historical experience and on appropriate and customary assumptions that are believed to be reasonable under the circumstances, the results of which form the basis for making judgments about the carrying values of assets and liabilities that are not readily apparent from other sources. Management is not aware of any specific event or circumstance that would require an update to its estimates or judgments or a revision of the carrying value of its assets or liabilities as of the date of issuance of this Quarterly Report on Form 10-Q. These estimates may change, as new events occur, and additional information is obtained. Actual results may differ significantly from these estimates under different assumptions or conditions. Equity Method Investments Teradyne accounts for investments using the equity method of accounting when it has significant influence over the financial and operating policies, but not control, of the investee. The equity method investments are initially recorded at cost and included in ‘Equity method investment’ in the consolidated balance sheet. Teradyne records its share of investee's net income or loss and other comprehensive income, and the amortization of equity method basis difference, calculated as the difference between the investment and the amount of underlying equity in net assets acquired, on a 3-month lag, which is applied consistently from period to period. Teradyne's share of investee's net income and the amortization of equity method basis difference are reported in ‘Equity in net earnings of affiliate’ in the consolidated statement of operations. Teradyne includes its share of investee's other comprehensive income and a cumulative translation adjustment in the consolidated statements of comprehensive income. Teradyne monitors on an ongoing basis its equity method investments for indicators of other-than-temporary declines in fair value below carrying value.

Recently Issued Accounting Pron

Recently Issued Accounting Pronouncements	9 Months Ended
	Sep. 29, 2024
Recently Issued Accounting Pronouncements	C. RECENTLY ISSUED ACCOUNTING PRONOUNCEMENTS In November 2023, the Financial Accounting Standards Board ("FASB") issued Accounting Standard Update ("ASU") No. 2023-07, "Segment Reporting (Topic 280): Improvements to Reportable Segment Disclosures" , which will require Teradyne to disclose significant segment expenses and other segment items used by the Chief Operating Decision Maker ("CODM") on an annual and interim basis as well as provide in interim periods all disclosures about a reportable segment’s profit or loss and assets that are currently required annually. Additionally, Teradyne will be required to disclose the title and position of the CODM. The new standard is effective for fiscal years beginning after December 15, 2023, and interim periods within fiscal years beginning after December 15, 2024, with early adoption permitted. This ASU will have no impact on results of operations, cash flows or financial condition. Upon adoption, Teradyne will apply the amendments in this ASU retrospectively to all prior period disclosures presented in the financial statements. In December 2023, FASB issued ASU 2023-09, “Income Taxes (Topic 740): Improvements to Income Tax Disclosures” , which requires expanded disclosures relating to the tax rate reconciliation, income taxes paid, income (loss) before income tax expense (benefit) and income tax expense (benefit), requiring a greater disaggregation of information for each. The provisions of ASU 2023-09 are effective for fiscal years beginning after December 15, 2024. The amendments in this update should be applied on a prospective basis, but retrospective application is permitted. This ASU will have no impact on results of operations, cash flows or financial condition.

Revenue

Revenue	9 Months Ended
	Sep. 29, 2024
Revenue from Contract with Customer [Abstract]
Revenue	D. REVENUE Disaggregation of Revenue The following table provides information about disaggregated revenue by timing of revenue recognition, primary geographical market, and major product lines. Semiconductor Test System Test Robotics Wireless Test System Memory Universal Mobile Total (in thousands) For the Three Months Ended September 29, 2024 (1) Timing of Revenue Recognition Point in Time $ 323,507 $ 143,581 $ 55,611 $ 71,607 $ 15,065 $ 29,465 $ 638,836 Over Time 68,848 6,798 17,701 1,811 168 3,136 98,462 Total $ 392,355 $ 150,379 $ 73,312 $ 73,418 $ 15,233 $ 32,601 $ 737,298 Geographical Market Asia Pacific $ 364,476 $ 137,890 $ 29,277 $ 10,873 $ 2,960 $ 24,342 $ 569,818 Americas 17,150 1,325 39,919 32,315 8,460 5,515 104,684 Europe, Middle East and Africa 10,729 11,164 4,116 30,230 3,813 2,744 62,796 Total $ 392,355 $ 150,379 $ 73,312 $ 73,418 $ 15,233 $ 32,601 $ 737,298 For the Three Months Ended October 1, 2023 (1) Timing of Revenue Recognition Point in Time $ 330,846 $ 86,247 $ 66,418 $ 68,938 $ 14,012 $ 32,638 $ 599,099 Over Time 73,264 7,506 16,785 1,607 1,135 4,336 104,633 Total $ 404,110 $ 93,753 $ 83,203 $ 70,545 $ 15,147 $ 36,974 $ 703,732 Geographical Market Asia Pacific $ 360,375 $ 91,352 $ 40,464 $ 15,430 $ 3,180 $ 24,727 $ 535,528 Americas 24,752 1,356 35,888 26,073 7,154 10,139 105,362 Europe, Middle East and Africa 18,983 1,045 6,851 29,042 4,813 2,108 62,842 Total $ 404,110 $ 93,753 $ 83,203 $ 70,545 $ 15,147 $ 36,974 $ 703,732 For the Nine Months Ended September 29, 2024 (2) Timing of Revenue Recognition Point in Time $ 896,635 $ 367,679 $ 157,203 $ 210,222 $ 49,850 $ 82,652 $ 1,764,241 Over Time 211,612 21,626 52,232 5,542 938 10,805 302,755 Total $ 1,108,247 $ 389,305 $ 209,435 $ 215,764 $ 50,788 $ 93,457 $ 2,066,996 Geographical Market Asia Pacific $ 1,016,674 $ 357,993 $ 76,317 $ 37,254 $ 11,361 $ 70,776 $ 1,570,375 Americas 59,912 13,631 105,197 82,220 28,195 16,240 305,395 Europe, Middle East and Africa 31,661 17,681 27,921 96,290 11,232 6,441 191,226 Total $ 1,108,247 $ 389,305 $ 209,435 $ 215,764 $ 50,788 $ 93,457 $ 2,066,996 For the Nine Months Ended October 1, 2023 (2) Timing of Revenue Recognition Point in Time $ 886,201 $ 260,052 $ 200,076 $ 194,698 $ 42,748 $ 108,262 $ 1,692,038 Over Time 219,436 21,890 52,030 5,731 3,364 11,210 313,661 Total $ 1,105,638 $ 281,942 $ 252,106 $ 200,429 $ 46,112 $ 119,472 $ 2,005,699 Geographical Market Asia Pacific $ 946,696 $ 270,297 $ 121,698 $ 43,530 $ 6,973 $ 70,320 $ 1,459,514 Americas 98,511 8,586 105,031 69,346 25,051 42,476 349,001 Europe, Middle East and Africa 60,431 3,059 25,377 87,553 14,088 6,676 197,184 Total $ 1,105,638 $ 281,942 $ 252,106 $ 200,429 $ 46,112 $ 119,472 $ 2,005,699 (1) Include s $ 0.8 million and $ 1.4 million in 2024, and 2023, respectively, for leases of Teradyne’s systems recognized outside Accounting Standards Codification (“ASC”) 606 “Revenue from Contracts with Customers.” (2) Includes $ 2.5 million and $ 3.9 million in 2024 and 2023, respectively, for leases of Teradyne’s systems recognized outside Accounting Standards Codification (“ASC”) 606 “Revenue from Contracts with Customers.” Contract Balances During the three and nine months ended September 29, 2024, Teradyne recognized $ 13.4 million and $ 60.2 million, respectively, that was included within the deferred revenue and customer advances balances at the beginning of the period. During the three and nine months ended October 1, 2023, Teradyne recognized $ 21.9 million and $ 91.3 million, respectively, that was included within the deferred revenue and customer advances balances at the beginning of the period. This revenue primarily relates to undelivered hardware, extended warranties, training, application support, and post contract support. Each of these represents a distinct performance obligation. As of September 29, 2024, Teradyne had $ 1,045.4 million of unsatisfied performance obligations. Teradyne expects to recognize approximately 93 % of the remaining performance obligations in the next 12 months and the remainder in 1 - 3 years. Deferred revenue and customer advances consist of the following and are included in short and long-term deferred revenue and customer advances on the balance sheet: September 29, December 31, (in thousands) Maintenance, service and training $ 57,866 $ 66,458 Customer advances, undelivered elements and other 44,116 35,731 Extended warranty 38,929 34,897 Total deferred revenue and customer advances $ 140,911 $ 137,086 Accounts Receivable During the three and nine months ended September 29, 2024, and October 1, 2023, Teradyne sold certain trade accounts receivables on a non-recourse basis to third-party financial institutions pursuant to factoring agreements. During the three months ended September 29, 2024, and October 1, 2023, total trade accounts receivable sold under the factoring agreements were $ 36.1 million and $ 94.1 million, respectively. During the nine months ended September 29, 2024, and October 1, 2023, total trade accounts receivable sold under the factoring agreements were $ 116.8 million and $ 191.2 million, respectively. Factoring fees for the sales of receivables were recorded in interest expense and were not material. Teradyne accounted for these transactions as sales of receivables and presented cash proceeds as cash provided by operating activities in the consolidated statements of cash flows.

Dispositions

Dispositions	9 Months Ended
	Sep. 29, 2024
Discontinued Operations and Disposal Groups [Abstract]
Dispositions	E. DISPOSITIONS On May 27, 2024, Teradyne completed the sale of the Device Interface Solutions ("DIS") business, a component of the Semiconductor Test segment, to Technoprobe S.p.A. ("Technoprobe") for $ 85.0 million in cash, net of cash and cash equivalents sold, and a customary working capital adjustment. The sale resulted in a pre-tax gain of $ 57.5 million recorded as 'Gain on sale of business' in the consolidated statement of operations. The transaction did not meet the criteria to be classified as a discontinued operation, as it did not represent a strategic shift that will have a major effect on operations and financial results. Assets and liabilities related to the DIS sale agreement met the criteria and were classified as held for sale in Teradyne’s consolidated balance sheet as of December 31, 2023, as follows: December 31, Current assets: Inventories, net $ 17,952 Prepayments 5,298 Total current assets held for sale 23,250 Property, plant and equipment, net 8,986 Operating lease right-of-use assets, net 2,545 Total assets held for sale $ 34,781 Current liabilities: Accounts payable $ 6,356 Other accrued liabilities 552 Operating lease liabilities 471 Total current liabilities held for sale 7,379 Long-term operating lease liabilities 2,000 Total liabilities held for sale $ 9,379 Net assets held for sale $ 25,402

Equity Method Investment

Equity Method Investment	9 Months Ended
	Sep. 29, 2024
Equity Method Investments and Joint Ventures [Abstract]
Equity Method Investment	F. EQUITY METHOD INVESTMENT On May 27, 2024, Teradyne paid $ 524.1 million to purchase a combination of previously issued and outstanding shares and shares newly issued by Technoprobe, S.p.A. ("Technoprobe"). The shares purchased represent 10 % of the issued and outstanding shares of Technoprobe. Teradyne also received a board seat as part of the purchase. Teradyne accounts for this investment using the equity method as a result of being able to exercise significant influence over the operating and financial decisions of Technoprobe. As of September 29, 2024, $ 538.4 million was recorded as 'Equity method investment' in the consolidated balance sheets. (in thousands) Balance at June 30, 2024 $ 524,060 Other comprehensive income related to investment 15,366 Equity in net earnings of affiliate ( 1,075 ) Balance at September 29, 2024 $ 538,351 Based on the quoted closing price of Technoprobe stock as of September 29, 2024, the fair value of the publicly traded investment was $ 471.8 million, and there was no other-than-temporary impairment identified. Teradyne's equity method basis difference was calculated as the difference between the investment and the amount of underlying equity in net assets acquired. The equity method basis difference calculated at acquisition attributable to developed technology, customer relationships, trade name, property, plant and equipment, inventory, and deferred tax liability was $ 204.7 million. The basis differences, net of tax, will be amortized over their estimated useful lives. Teradyne made an accounting policy election to report its share of Technoprobe's results on a 3-month lag, which is applied consistently from period to period. Teradyne records its share of Technoprobe's net income or loss and the amortization of equity method basis difference, as 'Equity in net earnings of affiliate' in the consolidated statements of operations. Teradyne includes its share of Technoprobe's other comprehensive income and a cumulative translation adjustment in the consolidated statements of comprehensive income .

Inventories

Inventories	9 Months Ended
	Sep. 29, 2024
Inventory Disclosure [Abstract]
Inventories	G. INVENTORIES Inventories, net consisted of the following at September 29, 2024, and December 31, 2023: September 29, December 31, (in thousands) Raw material $ 216,019 $ 258,422 Work-in-process 48,249 26,851 Finished goods 33,072 24,701 Total inventories, net (1) $ 297,340 $ 309,974 (1) Inventories, net at December 31, 2023, exclude $ 18.0 million of primarily work-in-process inventories, net classified as assets held for sale. See Note E: "Dispositions" for additional information. Inventory reserves at September 29, 2024, and December 31, 2023, were $ 140.5 million and $ 136.0 million, respectively.

Financial Instruments

Financial Instruments	9 Months Ended
	Sep. 29, 2024
Fair Value Disclosures [Abstract]
Financial Instruments	H. FINANCIAL INSTRUMENTS Cash Equivalents Teradyne considers all highly liquid investments with original maturities of 90 days or less at the date of acquisition to be cash equivalents. Marketable Securities Teradyne’s equity and debt mutual funds are classified as Level 1 and available-for-sale debt securities are classified as Level 2. The vast majority of Level 2 securities are fixed income securities priced by third party pricing vendors. These pricing vendors utilize the most recent observable market information in pricing these securities or, if specific prices are not available, use other observable inputs like market transactions involving identical or comparable securities. During the three and nine months ended September 29, 2024, and October 1, 2023, there were no transfers in or out of Level 1, Level 2, or Level 3 financial instruments. Realized gains recorded in the three and nine months ended September 29, 2024, were $ 0.8 million and $ 2.1 million, respectively. Realized gains recorded in the three and nine months ended October 1, 2023, were $ 0.1 million and $ 0.6 million, respectively. Realized losses recorded in the three and nine months ended September 29, 2024, were $ 0.0 million and $ 0.3 million, respectively. Realized losses recorded in the three and nine months ended October 1, 2023 , were $ 0.0 million and $ 0.3 million, respectively. Realized gains and losses are included in 'Other (income) expense, net' in the consolidated statement of operations. Unrealized gains on equity securities recorded in the three and nine months ended September 29, 2024, were $ 2.2 million and $ 5.4 million, respectively. Unrealized gains on equity securities recorded in the three and nine months ended October 1, 2023, were $ 0.0 million and $ 4.6 million, respectively. There were no unrealized losses on equity securities recorded in the three and nine months ended September 29, 2024. Unrealized losses on equity securities recorded in the three and nine months ended October 1, 2023, were $ 1.7 million. Unrealized gains and losses on equity securities are included in 'Other (income) expense, net' in the consolidated statement of operations. Unrealized gains and losses on available-for-sale debt securities are included in 'Accumulated other comprehensive income (loss)' in the consolidated balance sheet. The cost of securities sold is based on average cost. The following tables set forth by fair value hierarchy Teradyne’s financial assets and liabilities that were measured at fair value on a recurring basis as of September 29, 2024, and December 31, 2023. September 29, 2024 Quoted Prices Significant Significant Total (in thousands) Assets Cash $ 198,946 $ — $ — $ 198,946 Cash equivalents 308,000 3,090 — 311,090 Available-for-sale securities: U.S. Treasury securities — 41,833 — 41,833 Corporate debt securities — 37,149 — 37,149 Certificates of deposit and time deposits — 21,741 — 21,741 Debt mutual funds 8,640 — — 8,640 U.S. government agency securities — 3,931 — 3,931 Non-U.S. government securities — 801 — 801 Equity securities: Mutual funds 53,480 — — 53,480 $ 569,066 $ 108,545 $ — $ 677,611 Derivative assets — 332 — 332 Total $ 569,066 $ 108,877 $ — $ 677,943 Liabilities Derivative liabilities — 1,435 — $ 1,435 Total $ — $ 1,435 $ — $ 1,435 Reported as follows: (Level 1) (Level 2) (Level 3) Total (in thousands) Assets Cash and cash equivalents $ 506,946 $ 3,090 $ — $ 510,036 Marketable securities — 41,631 — 41,631 Long-term marketable securities 62,120 63,824 — 125,944 Other current assets — 332 — 332 Total $ 569,066 $ 108,877 $ — $ 677,943 Liabilities Other current liabilities — 1,435 — 1,435 Total $ — $ 1,435 $ — $ 1,435 December 31, 2023 Quoted Prices Significant Significant Total (in thousands) Assets Cash $ 298,156 $ — $ — $ 298,156 Cash equivalents 453,298 6,117 — 459,415 Available-for-sale securities: Corporate debt securities — 52,734 — 52,734 U.S. Treasury securities — 41,808 — 41,808 Certificates of deposit and time deposits — 21,772 — 21,772 Debt mutual funds 8,773 — — 8,773 U.S. government agency securities — 4,892 — 4,892 Commercial paper — 1,667 — 1,667 Non-U.S. government securities — 810 — 810 Equity securities: Mutual Funds 47,132 — — 47,132 $ 807,359 $ 129,800 $ — $ 937,159 Derivative assets — 18,746 — 18,746 Total $ 807,359 $ 148,546 $ — $ 955,905 Liabilities Derivative liabilities — 2,545 — 2,545 Total $ — $ 2,545 $ — $ 2,545 Reported as follows: (Level 1) (Level 2) (Level 3) Total (in thousands) Assets Cash and cash equivalents $ 751,454 $ 6,117 $ — $ 757,571 Marketable securities — 62,154 — 62,154 Long-term marketable securities 55,905 61,529 — 117,434 Other current assets — 18,746 — 18,746 Total $ 807,359 $ 148,546 $ — $ 955,905 Liabilities Other current liabilities $ — $ 2,545 $ — $ 2,545 Total $ — $ 2,545 $ — $ 2,545 The carrying amounts and fair values of Teradyne’s financial instruments at September 29, 2024, and December 31, 2023, were as follows: September 29, 2024 December 31, 2023 Carrying Value Fair Value Carrying Value Fair Value (in thousands) Assets Cash and cash equivalents $ 510,036 $ 510,036 $ 757,571 $ 757,571 Marketable securities 167,575 167,575 179,588 179,588 Derivative assets 332 332 18,746 18,746 Liabilities Derivative liabilities 1,435 1,435 2,545 2,545 The fair values of accounts receivable, net and accounts payable approximate the carrying value due to the short-term nature of these instruments. The following table summarizes the composition of available-for-sale marketable securities at September 29, 2024: September 29, 2024 Available-for-Sale Cost Unrealized Unrealized Fair Fair Market (in thousands) U.S. Treasury securities $ 45,522 $ 106 $ ( 3,795 ) $ 41,833 $ 22,985 Corporate debt securities $ 39,986 $ 323 $ ( 3,160 ) $ 37,149 $ 25,248 Certificates of deposit and time deposits 21,741 — — 21,741 — Debt mutual funds 8,846 — ( 206 ) 8,640 3,319 U.S. government agency securities 3,921 11 ( 1 ) 3,931 876 Non-U.S. government securities 801 — — 801 — $ 120,817 $ 440 $ ( 7,162 ) $ 114,095 $ 52,428 Reported as follows: Cost Unrealized Unrealized Fair Fair Market (in thousands) Marketable securities $ 41,673 20 $ ( 62 ) $ 41,631 $ 9,973 Long-term marketable securities 79,144 420 ( 7,100 ) 72,464 42,455 $ 120,817 $ 440 $ ( 7,162 ) $ 114,095 $ 52,428 The following table summarizes the composition of available-for-sale marketable securities at December 31, 2023: December 31, 2023 Available-for-Sale Cost Unrealized Unrealized Fair Fair Market (in thousands) Corporate debt securities $ 56,458 $ 201 $ ( 3,925 ) $ 52,734 $ 44,263 U.S. Treasury securities 45,725 14 ( 3,931 ) 41,808 35,080 Certificates of deposit and time deposits 21,772 — — 21,772 — Debt mutual funds 9,081 — ( 308 ) 8,773 3,303 U.S. government agency securities 4,898 — ( 6 ) 4,892 4,892 Commercial paper 1,633 34 — 1,667 — Non-U.S. government securities 810 — — 810 — $ 140,377 $ 249 $ ( 8,170 ) $ 132,456 $ 87,538 Reported as follows: Cost Unrealized Unrealized Fair Fair Market (in thousands) Marketable securities $ 62,385 $ 36 $ ( 267 ) 62,154 $ 34,844 Long-term marketable securities 77,992 213 ( 7,903 ) 70,302 52,694 $ 140,377 $ 249 $ ( 8,170 ) $ 132,456 $ 87,538 As of September 29, 2024, the fair market value of investments with unrealized losses less than one year and greater than one year totaled $ 8.3 million and $ 44.1 million, respectively. As of December 31, 2023, the fair market value of investments with unrealized losses for less than one year and greater than one year totaled $ 22.3 million and $ 65.2 million, respectively. Teradyne reviews its investments to identify and evaluate investments that have an indication of possible impairment. Based on this review, Teradyne determined that the unrealized losses related to these investments at September 29, 2024, and December 31, 2023, were not other than temporary. The contractual maturities of investments in available-for-sale securities held at September 29, 2024, were as follows: September 29, 2024 Cost Fair Market (in thousands) Due within one year $ 41,673 $ 41,631 Due after 1 year through 5 years 25,690 25,729 Due after 5 years through 10 years 7,950 7,908 Due after 10 years 36,658 30,187 Total $ 111,971 $ 105,455 Contractual maturities of investments in available-for-sale securities held at September 29, 2024, exclude debt mutual funds with a fair market value of $ 8.6 million as they do not have a contractual maturity date. Derivatives Teradyne conducts business in various foreign countries, with certain transactions denominated in local currencies. As a result, Teradyne is exposed to risks relating to changes in foreign currency exchange rates. Teradyne’s foreign currency risk management objective is to minimize the effect of exchange rate fluctuations associated with the remeasurement of monetary assets and liabilities denominated in foreign currencies, and changes in its cash inflows attributable to the forecasted cash flows from certain foreign currency denominated revenues. To minimize the effect of exchange rate fluctuations associated with the remeasurement of monetary assets and liabilities denominated in foreign currencies, Teradyne enters into foreign currency forward contracts. The change in fair value of these derivatives is recorded directly in earnings and is used to offset the change in value of monetary assets and liabilities denominated in foreign currencies. Teradyne also enters into foreign currency forward and option contracts designated as cash flow hedges to hedge the risk of changes in its cash inflows attributable to changes in foreign currency exchange rates. The cash flow hedges have maturities of less than six months and mature in the period of revenue recognition for certain products and services in backlog and forecasted to be recognized in a future period. Teradyne evaluates cash flow hedges for effectiveness at inception based on the critical terms match method. The hedges are not expected to incur any ineffectiveness however a quarterly qualitative assessment of effectiveness is done to determine if the critical terms match method remains appropriate to use. The change in fair value of the contracts is recorded in accumulated other comprehensive income (loss) and reclassified to earnings at maturity date. Teradyne does not use derivative financial instruments for speculative purposes. At September 29, 2024, and December 31, 2023, Teradyne had the following contracts to buy and sell non-U.S. currencies for U.S. dollars and other non-U.S. currencies with the following notional amounts: Net Notional Value September 29, December 31, (in millions) Currency Hedged (Buy/Sell) U.S. dollar/Taiwan dollar 29.6 42.7 U.S. dollar/Japanese yen 21.7 11.0 U.S. dollar/Korean won 8.9 7.2 U.S. dollar/British pound sterling 1.0 1.5 U.S. dollar/Danish krone — 36.0 Danish krone/U.S. dollar 25.7 0.7 Euro/U.S. dollar 24.8 25.3 Singapore dollar/U.S. dollar 23.0 16.6 Philippine peso/U.S. dollar 9.7 10.1 Chinese yuan/U.S. dollar 1.7 1.0 Total $ 146.1 $ 152.1 The fair value of the outstanding contracts was a net loss of $ 0.8 million and a net loss of $ 1.8 million at September 29, 2024, and December 31, 2023, respectively. Unrealized gains and losses on foreign currency forward contracts and foreign currency remeasurement gains and losses on monetary assets and liabilities are included in 'Other (income) expense, net' in the consolidated statement of operations. At September 29, 2024, and December 31, 2023, Teradyne had the following cash flow hedge contracts to buy and sell non-U.S. currencies for U.S. dollars with the following notional amounts: Net Notional Value September 29, December 31, (in millions) Currency Hedged (Buy/Sell) U.S. dollar/Japanese yen $ 12.1 $ 35.5 Total $ 12.1 $ 35.5 The fair value of the outstanding cash flow hedge contracts was a loss of $ 0.3 million and a gain of $ 0.6 million at September 29, 2024, and December 31, 2023, respectively. Unrealized gains and losses on foreign currency cash flow hedge contracts are included in accumulated other comprehensive income (loss). At maturity, the gains or losses associated with cash flow hedge contracts are recorded to revenue. On November 7, 2023, in connection with Teradyne's agreement to acquire 10 % investment in Technoprobe S.p.A, Teradyne purchased a call option to buy 481.0 million Euros. The expiration date of the option was April 26, 2024 . On April 12, 2024, Teradyne entered into a forward to buy 481.0 million Euros which expired on May 23, 2024 . At December 31, 2023, the fair value of the outstanding contract was $ 17.4 million . For the nine months ended September 29, 2024, a realized loss of $ 9.8 million was recorded in 'Other (income) expense, net' in the consolidated statement of operations. The following table summarizes the fair value of derivative instruments as of September 29, 2024, and December 31, 2023: Balance Sheet Location September 29, December 31, (in thousands) Derivatives not designated as hedging instruments: Foreign exchange forward contracts Other current assets 332 733 Foreign exchange forward contracts Other current liabilities ( 1,102 ) ( 2,545 ) Foreign exchange option contracts Other current assets — 17,364 Derivatives designated as hedging instruments: Foreign exchange forward contracts Other current assets — 648 Foreign exchange forward contracts Other current liabilities ( 333 ) — Total derivatives $ ( 1,103 ) $ 16,200 The following table summarizes the effect of derivative instruments recognized in the statement of operations for the three and nine months ended September 29, 2024, and October 1, 2023: For the Three Months For the Nine Months Location of (Gains) Losses September 29, October 1, September 29, October 1, (in thousands) (in thousands) Derivatives not designated as hedging instruments: Foreign exchange forward contracts (1) Other (income) expense, net $ 4,829 $ ( 1,886 ) $ 686 $ ( 4,667 ) Foreign exchange option contracts Other (income) expense, net — — 9,764 — Derivatives designated as hedging instruments: Foreign exchange forward and option contracts Revenue — ( 3,960 ) ( 2,280 ) ( 2,008 ) Total Derivatives $ 4,829 $ ( 5,846 ) $ 8,170 $ ( 6,675 ) (1) The table does not reflect the corresponding gains and losses from the remeasurement of the monetary assets and liabilities denominated in foreign currencies. For the three and nine months ended September 29, 2024, net losses (gains) from remeasurement of monetary assets and liabilities denominated in foreign currencies were $ ( 2.9 ) million and $ 3.1 million, respectively. For the three and nine months ended October 1, 2023, net losses from remeasurement of monetary assets and liabilities denominated in foreign currencies were $ 5.3 million and $ 12.3 million, respectively. See Note I: “Debt” regarding derivatives related to the convertible senior notes.

Debt

Debt	9 Months Ended
	Sep. 29, 2024
Debt	I. DEBT Convertible Senior Notes On December 12, 2016, Teradyne completed a private offering of $ 460.0 million aggregate principal amount of 1.25 % convertible senior unsecured notes (the “Notes”) and received net proceeds, after issuance costs, of approximately $ 450.8 million, $ 33.0 million of which was used to pay the net cost of the convertible note hedge transactions and $ 50.1 million of which was used to repurchase 2.0 million shares of Teradyne’s common stock under its existing stock repurchase program from purchasers of the Notes in privately negotiated transactions effected through one of the initial purchasers or its affiliates conducted concurrently with the pricing of the Note offering. The Notes bore interest at a rate of 1.25 % per year, payable semiannually in arrears on June 15 and December 15 of each year . The Notes matured on December 15, 2023 . Concurrent with the offering of the Notes, Teradyne entered into convertible note hedge transactions (the “Note Hedge Transactions”) with the initial purchasers or their affiliates (the “Option Counterparties”). The Note Hedge Transactions cover, subject to customary anti-dilution adjustments, the number of shares of the common stock that underlie the Notes. Separately and concurrent with the pricing of the Notes, Teradyne entered into warrant transactions with the Option Counterparties (the “Warrant Transactions”) in which it sold net-share-settled (or, at its election subject to certain conditions, cash-settled) warrants to the Option Counterparties. These transactions have been accounted for as an adjustment to Teradyne's shareholders’ equity. The Warrant Transactions, which began expiring March 18, 2024 , and continued to expire through July 10, 2024 , covered, subject to customary anti-dilution adjustments, approximately 1.3 million shares of common stock. During the three and nine months ended September 29, 2024, 1.3 million and 14.7 million warrants expired, resulting in the issuance of 1.2 million and 10.0 million shares of Teradyne common stock, respectively. As of the final date of expiration, July 10, 2024, the strike price of the warrants was approximately $ 39.35 per shares. The Warrant Transactions resulted in additional shares of Teradyne’s common stock being issued to the extent that the market price per share of Teradyne’s common stock, as measured under the terms of the Warrant Transactions, exceeds the applicable strike price of the warrants. The interest expense on Teradyne's senior notes for three and nine months ended October 1, 2023, was as follows: For the Three Months For the Nine Months September 29, October 1, September 29, October 1, (in thousands) (in thousands) Contractual interest expense on the coupon $ — $ 74 $ — $ 312 Amortization of debt issuance fees recognized as interest expense — — — 113 Total interest expense on the convertible debt $ — $ 74 $ — $ 425 Revolving Credit Facility On May 1, 2020, Teradyne entered into a credit agreement (the “Credit Agreement”) with Truist Bank, as administrative agent and collateral agent, and the lenders party thereto. The Credit Agreement provided for a three-year , senior secured revolving credit facility of $ 400.0 million (the “Credit Facility”). On December 10, 2021, the Credit Agreement was amended to extend the maturity date of the Credit Facility to December 10, 2026. On October 5, 2022, the Credit Agreement was amended to increase the amount of the Credit Facility to $ 750.0 million from $ 400.0 million. On November 7, 2023, the Credit Agreement was amended to allow for the purchase of the shares of Technoprobe. The Credit Agreement provides that, subject to customary conditions, Teradyne may seek to obtain from existing or new lenders the available incremental amount under the Credit Facility, not to exceed the greater of $ 200.0 million or 15 % of consolidated EBIDTA. 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. Teradyne is not required to repay any loans under the Credit Facility prior to maturity, subject to certain customary exceptions. Teradyne is permitted to prepay all or any portion of the loans under the Credit Facility prior to maturity without premium or penalty, other than customary SOFR breakage costs. The Credit Agreement contains customary events of default, representations, warranties, and affirmative and negative covenants that, among other things, limit Teradyne’s ability to sell assets, grant liens on assets, incur other secured indebtedness and make certain investments and restricted payments, all subject to exceptions set forth in the Credit Agreement. The Credit Agreement also requires Teradyne to satisfy two financial ratios measured at the end of each fiscal quarter: a consolidated leverage ratio and an interest coverage ratio. The Credit Facility is guaranteed by certain of Teradyne’s domestic subsidiaries and collateralized by assets of Teradyne and such subsidiaries, including a pledge of 65 % of the capital stock of certain foreign subsidiaries. On May 16, 2024, Teradyne borrowed $ 185.0 million under the Credit Agreement to support the acquisition of 10 % of the issued and outstanding shares of Technoprobe. Teradyne fully repaid its borrowings on the revolving credit facility prior to September 29, 2024 . There was no outstanding revolver balance as of September 29, 2024. As of November 1 , 2024, the Credit Facility was undrawn, and Teradyne was in compliance with all covenants under the Credit Agreement.

Prepayments

Prepayments	9 Months Ended
	Sep. 29, 2024
Prepayments [Abstract]
Prepayments	J. PREPAYMENTS Prepayments consist of the following: September 29, December 31, (in thousands) Contract manufacturer and supplier prepayments $ 439,647 $ 502,257 Prepaid taxes 20,734 16,083 Prepaid maintenance and other services 19,040 17,592 Other prepayments 10,127 13,038 Total prepayments (1) $ 489,548 $ 548,970 (1) Exclude s $ 5.3 million at December 31, 2023 , of contract manufacturer and supplier prepayments, classified as assets held for sale. See Note E: “Dispositions” for additional information.

Product Warranty

Product Warranty	9 Months Ended
	Sep. 29, 2024
Product Warranty	K. PRODUCT WARRANTY Teradyne generally provides a one-year warranty on its products, commencing upon installation, acceptance or shipment. A provision is recorded upon revenue recognition to cost of revenues for estimated warranty expense based on historical experience. Related costs are charged to the warranty accrual as incurred. The balance below is included in other accrued liabilities. For the Three Months For the Nine Months September 29, October 1, September 29, October 1, (in thousands) (in thousands) Balance at beginning of period $ 15,244 $ 12,543 $ 15,698 $ 14,181 Accruals for warranties issued during the period 2,149 8,859 8,331 16,237 Accruals related to pre-existing warranties ( 545 ) ( 795 ) ( 1,513 ) ( 1,552 ) Settlements made during the period ( 2,990 ) ( 5,892 ) ( 8,658 ) ( 14,151 ) Balance at end of period $ 13,858 $ 14,715 $ 13,858 $ 14,715 When Teradyne receives revenue for extended warranties beyond one year it is treated as a separate performance obligation and deferred and recognized on a straight-line basis over the contract period. Related costs are expensed as incurred. The balance below is included in short and long-term deferred revenue and customer advances. For the Three Months For the Nine Months September 29, October 1, September 29, October 1, (in thousands) (in thousands) Balance at beginning of period $ 33,512 $ 44,422 $ 34,897 $ 56,180 Deferral of new extended warranty revenue 9,714 2,734 22,316 11,615 Recognition of extended warranty deferred revenue ( 4,297 ) ( 8,313 ) ( 18,284 ) ( 28,952 ) Balance at end of period $ 38,929 $ 38,843 $ 38,929 $ 38,843

Stock-Based Compensation

Stock-Based Compensation	9 Months Ended
	Sep. 29, 2024
Stock-Based Compensation	L. STOCK-BASED COMPENSATION On February 1, 2023 (the “Retirement Date”), Mark E. Jagiela retired as Chief Executive Officer of Teradyne and a member of Teradyne’s Board of Directors, and Teradyne entered into an agreement (the “Retirement Agreement”) with Mr. Jagiela. Under the Retirement Agreement, Mr. Jagiela’s unvested time-based restricted stock units and stock options granted prior to his Retirement Date were modified to allow continued vesting; and any vested options or options that vest during that period may be exercised for the remainder of the applicable option term. During the nine months ended October 1, 2023 , Teradyne recorded a stock-based compensation expense of $ 5.9 million related to the Retirement Agreement. Under Teradyne’s stock compensation plans, Teradyne grants time-based restricted stock units, performance-based restricted stock units and stock options, and employees are eligible to purchase Teradyne’s common stock through its Employee Stock Purchase Plan (“ESPP”). Service-based restricted stock unit awards granted to employees vest in equal annual installments over four years . Restricted stock unit awards granted to non-employee directors vest after a one-year period, with 100 % of the award vesting on the earlier of (a) the first anniversary of the grant date or (b) the date of the following year’s Annual Meeting of Shareholders. Teradyne expenses the cost of the restricted stock unit awards subject to time-based vesting, which is determined to be the fair market value of the shares at the date of grant, ratably over the period during which the restrictions lapse. Performance-based restricted stock units (“PRSUs”) granted to Teradyne’s executive officers may have a performance metric based on relative total shareholder return (“TSR”). Teradyne’s three-year TSR performance is measured against the New York Stock Exchange (“NYSE”) Composite Index. The final number of TSR PRSUs that vest will vary based upon the level of performance achieved from 0 % to 200 % of the target shares. The TSR PRSUs will vest upon the three-year anniversary of the grant date. The TSR PRSUs are valued using a Monte Carlo simulation model. The number of units expected to be earned, based upon the achievement of the TSR market condition, is factored into the grant date Monte Carlo valuation. Compensation expense is recognized on a straight-line basis over the shorter of the three-year service period or the period from the grant to the date described in the retirement provisions below. Compensation expense for executive officers meeting the retirement provisions prior to the grant date is recognized during the year following the grant. Compensation expense is recognized regardless of the eventual number of units that are earned based upon the market condition, provided the executive officer remains an employee at the end of the three-year period. Compensation expense is reversed if at any time during the three-year service period the executive officer is no longer an employee, subject to the retirement and termination eligibility provisions noted below. PRSUs granted to Teradyne’s executive officers may also have a performance metric based on three-year cumulative non-GAAP profit before interest and tax (“PBIT”) as a percent of Teradyne’s revenue. Non-GAAP PBIT is a financial measure equal to GAAP income from operations less restructuring and other, net; amortization of acquired intangible assets; acquisition and divestiture related charges or credits; pension actuarial gains and losses; non-cash convertible debt interest expense; and other non-recurring gains and charges. The final number of PBIT PRSUs that vest will vary based upon the level of performance achieved from 0 % to 200 % of the target shares. The PBIT PRSUs will vest upon the three-year anniversary of the grant date. Compensation expense is recognized on a straight-line basis over the shorter of the three-year service period or the period from the grant date to the date described in the retirement provisions below. Compensation expense for executive officers meeting the retirement provisions prior to the grant date is recognized during the year following the grant. Compensation expense is recognized based on the number of units that are earned based upon the three-year Teradyne PBIT as a percent of Teradyne’s revenue, provided the executive officer remains an employee at the end of the three-year period subject to the retirement and termination eligibility provisions noted below. If a PRSU recipient’s employment ends prior to the determination of the performance percentage due to (1) death or (2) after attaining both at least age sixty and at least ten years of service, retirement or termination other than for cause, then all or a portion of the recipient’s PRSUs (based on the actual performance percentage achieved on the determination date) will vest on the date the performance percentage is determined. Except as set forth in the preceding sentence, no PRSUs will vest if the executive officer is no longer an employee at the end of the three-year period. Stock options to purchase Teradyne’s common stock at 100 % of the fair market value on the grant date vest in equal annual installments over four years from the grant date and have a maximum term of seven years . On January 22, 2024, the Board enacted the Executive Retirement Policy for Restricted Stock Unit and Option Vesting (the "Retirement Policy"). Under the Retirement Policy, an executive officer that is over the age of 65 and has 10 or more years of service as of the effective date of his or her retirement will be eligible for continued vesting of his or her unvested time-based restricted stock units and stock options granted prior to his or her retirement date. During the nine months ended September 29, 2024, and October 1, 2023, Teradyne granted 0.6 million and 0.5 million of service-based restricted stock unit awards to employees at a weighted average grant date fair value of $ 95.98 and $ 102.66 , respectively, and less than 0.1 million and 0.1 million of service-based restricted stock unit awards to non-employee directors at a weighted average grant date fair value of $ 120.38 and $ 90.50 , respectively. During the nine months ended September 29, 2024, and October 1, 2023, Teradyne granted 0.1 million and 0.1 million of PBIT PRSUs with a weighted average grant date fair value of $ 94.51 and $ 102.91 , respectively. During the nine months ended September 29, 2024, and October 1, 2023, Teradyne granted 0.1 million and 0.1 million of TSR PRSUs, with a weighted average grant date fair value of $ 102.51 and $ 139.04 , respectively. The grant date fair value was estimated using the Monte Carlo simulation model with the following assumptions: For the Nine Months September 29, October 1, Risk-free interest rate 3.9 % 4.0 % Teradyne volatility-historical 42.4 % 49.7 % NYSE Composite Index volatility-historical 15.6 % 24.1 % Dividend yield 0.5 % 0.4 % Expected volatility was based on the historical volatility of Teradyne’s stock and the NYSE Composite Index over the most recent three-year period. The risk-free interest rate was determined using the U.S. Treasury yield curve in effect at the time of the applicable grant. Dividend yield was based upon an estimated annual dividend amount of $ 0.48 per share divided by Teradyne’s stock price on the grant dates, which have a weighted average grant date stock price of $ 95.83 for the 2024 grants, and an estimated annual dividend amount of $ 0.44 per share divided by Teradyne’s stock price on the grant date of $ 104.12 for the 2023 grant. During the nine months ended September 29, 2024, and October 1, 2023, Teradyne granted 0.1 million and 0.1 million of service-based stock options to executive officers at a weighted average grant date fair value of $ 37.50 and $ 41.23 , respectively. The fair value of stock options was estimated using the Black-Scholes option-pricing model with the following assumptions: For the Nine Months September 29, October 1, Expected life (years) 4.0 4.0 Risk-free interest rate 4.0 % 3.8 % Volatility-historical 46.3 % 46.6 % Dividend yield 0.5 % 0.4 % Teradyne determined the stock options’ expected life based upon historical exercise data for executive officers, the age of the executive officers and the terms of the stock option grant. Volatility was determined using historical volatility for a period equal to the expected life. The risk-free interest rate was determined using the U.S. Treasury yield curve in effect at the time of grant. Dividend yield was based upon an estimated annual dividend amount of $ 0.48 per share divided by Teradyne’s stock price on the grant date of $ 95.14 for the 2024 grant and an estimated annual dividend amount of $ 0.44 per share divided by Teradyne’s stock price on the grant date of $ 104.15 for the 2023 grant.

Accumulated Other Comprehensive

Accumulated Other Comprehensive Income (Loss)	9 Months Ended
	Sep. 29, 2024
Accumulated Other Comprehensive Income (Loss)	M. ACCUMULATED OTHER COMPREHENSIVE INCOME (LOSS) Changes in accumulated other comprehensive income (loss), which are presented net of tax, consist of the following: Foreign Unrealized Unrealized (Losses) Gains on Cash Flow Hedges Retirement Total (in thousands) Nine Months Ended September 29, 2024 Balance at December 31, 2023, net of tax of $ 0 , $( 1,728 ), $ 142 , $( 1,132 ), respectively $ ( 22,442 ) $ ( 6,194 ) $ 506 $ 1,152 $ ( 26,978 ) Other comprehensive (loss) gain before reclassifications, net of tax of $ 0 , $ 205 , $ 285 , $ 0 , respectively 22,751 885 1,014 — 24,650 Amounts reclassified from accumulated other comprehensive income (loss), net of tax of $ 0 , $ 24 , $( 500 ), $( 1 ), respectively — 86 ( 1,780 ) ( 6 ) ( 1,700 ) Net current period other comprehensive (loss) gain, net of tax of $ 0 , $ 229 , $( 215 ), $( 1 ), respectively 22,751 971 ( 766 ) ( 6 ) 22,950 Balance at September 29, 2024, net of tax of $ 0 , $( 1,499 ), $( 73 ), $( 1,133 ), respectively $ 309 $ ( 5,223 ) $ ( 260 ) $ 1,146 $ ( 4,028 ) Nine Months Ended October 1, 2023 Balance at December 31, 2022, net of tax of $ 0 , $( 2,308 ), $( 708 ), $( 1,130 ), respectively $ ( 39,849 ) $ ( 8,661 ) $ ( 2,517 ) $ 1,159 $ ( 49,868 ) Other comprehensive (loss) gain before reclassifications, net of tax of $ 0 , $( 408 ), $ 1,816 , $ 0 , respectively ( 2,073 ) ( 903 ) 6,456 — 3,480 Amounts reclassified from accumulated other comprehensive income (loss), net of tax of $ 0 , $ 9 , $( 441 ), $( 1 ), respectively — 33 ( 1,567 ) ( 6 ) ( 1,540 ) Net current period other comprehensive (loss) gain, net of tax of $ 0 , $( 399 ), $ 1,375 , $( 1 ), respectively ( 2,073 ) ( 870 ) 4,889 ( 6 ) 1,940 Balance at October 1, 2023, net of tax of $ 0 , $( 2,707 ), $ 667 , $( 1,131 ), respectively $ ( 41,922 ) $ ( 9,531 ) $ 2,372 $ 1,153 $ ( 47,928 ) Reclassifications out of accumulated other comprehensive income (loss) to the statement of operations for the three and nine months ended September 29, 2024, and October 1, 2023, were as follows: Details about Accumulated Other Comprehensive Income (Loss) Components For the Three Months For the Nine Months Affected Line Item September 29, October 1, September 29, October 1, (in thousands) (in thousands) Available-for-sale marketable securities: Unrealized (losses) gains, net of tax of $ 2 , $ 0 , $( 24 ), $( 9 ), respectively $ 7 $ — $ ( 86 ) $ ( 33 ) Other (income) expense, net Cash flow hedges: Unrealized (losses) gains, net of tax of $ 0 , $ 869 , $ 500 , $ 441 , respectively — 3,091 1,780 1,567 Revenue Defined benefit pension and postretirement plans: Amortization of prior service credit, net of tax of $ 0 , $ 0 , $ 1 , $ 1 , respectively 2 2 6 6 (a) Total reclassifications, net of tax of $ 2 , $ 869 , $ 477 , $ 433 respectively $ 9 $ 3,093 $ 1,700 $ 1,540 Net income The amortization of prior service credit is included in the computation of net periodic postretirement benefit cost. See Note Q: “Retirement Plans.”

Goodwill and Acquired Intangibl

Goodwill and Acquired Intangible Assets	9 Months Ended
	Sep. 29, 2024
Goodwill and Acquired Intangible Assets	N. GOODWILL AND ACQUIRED INTANGIBLE ASSETS Goodwill Teradyne performs its annual goodwill impairment test as required under the provisions of ASC 350-10, “Intangibles—Goodwill and Other” on December 31 of each fiscal year unless interim indicators of impairment exist. In the nine months ended September 29, 2024, there were no interim indicators of impairment. Goodwill is considered impaired when the net book value of a reporting unit exceeds its estimated fair value. The changes in the carrying amount of goodwill by reportable segments for the nine months ended September 29, 2024, were as follows: Robotics Wireless Semiconductor System Total (in thousands) Balance at December 31, 2023 Goodwill $ 395,463 $ 361,819 $ 262,237 $ 158,699 $ 1,178,218 Accumulated impairment losses — ( 353,843 ) ( 260,540 ) ( 148,183 ) ( 762,566 ) Total Goodwill 395,463 7,976 1,697 10,516 415,652 Foreign currency translation adjustment 3,765 — ( 5 ) — 3,760 Balance at September 29, 2024 Goodwill $ 399,229 $ 361,819 $ 262,232 $ 158,699 1,181,978 Accumulated impairment losses — ( 353,843 ) ( 260,540 ) ( 148,183 ) ( 762,566 ) Total Goodwill $ 399,229 $ 7,976 $ 1,692 $ 10,516 $ 419,412 Intangible Assets Amortizable intangible assets consist of the following and are included in intangible assets, net on the balance sheet: Gross Accumulated Foreign Net (in thousands) Balance at September 29, 2024 Developed technology $ 267,706 $ ( 252,406 ) $ ( 5,337 ) $ 9,963 Customer relationships 52,109 ( 49,134 ) 210 3,185 Tradenames and trademarks 59,007 ( 49,618 ) ( 1,249 ) 8,140 Total intangible assets $ 378,822 $ ( 351,158 ) $ ( 6,376 ) $ 21,288 Balance at December 31, 2023 Developed technology $ 267,706 $ ( 243,191 ) $ ( 5,343 ) $ 19,172 Customer relationships 52,109 ( 47,850 ) 232 4,491 Tradenames and trademarks 59,007 ( 46,021 ) ( 1,245 ) 11,741 Total intangible assets $ 378,822 $ ( 337,062 ) $ ( 6,356 ) $ 35,404 Aggregate intangible asset amortization expense was $ 4.7 million and $ 14.1 million , respectively, for the three and nine months ended September 29, 2024, and $ 4.7 million and $ 14.3 million , respectively, for the three and nine months ended October 1, 2023. Estimated intangible asset amortization expense for each of the five succeeding fiscal years and thereafter is as follows: Year Amortization (in thousands) 2024 $ 4,775 2025 11,454 2026 2,402 2027 1,185 2028 1,104 Thereafter 368

Net Income Per Common Share

Net Income Per Common Share	9 Months Ended
	Sep. 29, 2024
Net Income per Common Share	O. NET INCOME PER COMMON SHARE The following table sets forth the computation of basic and diluted net income per common share: For the Three Months For the Nine Months September 29, October 1, September 29, October 1, (in thousands, except per share amounts) (in thousands, except per share amounts) Net income for basic and diluted net income per share $ 145,649 $ 128,116 $ 396,119 $ 331,698 Weighted average common shares-basic 163,002 153,762 157,951 154,809 Effect of dilutive potential common shares: Restricted stock units 768 455 637 410 Convertible note hedge warrant shares (1) 460 9,168 4,751 9,009 Stock options 13 26 13 39 Employee stock purchase plan 10 10 5 8 Incremental shares from assumed conversion of convertible notes (2) — 629 — 762 Dilutive potential common shares 1,251 10,288 5,406 10,228 Weighted average common shares-diluted 164,253 164,050 163,357 165,037 Net income per common share-basic $ 0.89 $ 0.83 $ 2.51 $ 2.14 Net income per common share-diluted $ 0.89 $ 0.78 $ 2.42 $ 2.01 (1) Convertible notes hedge warrant shares were calculated using the difference between the average Teradyne stock price for the period and the warrant price, multiplied by the number of warrant shares. The result of this calculation, representing the total intrinsic value of the warrant, was divided by the average Teradyne stock price for the period. (2) Incremental shares from assumed conversion of the convertible notes were calculated using the difference between the average Teradyne stock price for the period and the conversion price, multiplied by the number of convertible notes shares. The result of this calculation, representing the total intrinsic value of the convertible notes, was divided by the average Teradyne stock price for the period. The computation of diluted net income per common share for the three and nine months ended September 29, 2024, excludes the effect of the potential vesting of 0.1 million and 0.5 million, respectively, of restricted stock units because the effect would have been anti-dilutive. The computation of diluted net income per common share for the three and nine months ended October 1, 2023, excludes the effect of the potential vesting of 0.1 million and 0.4 million, respectively, of restricted stock units because the effect would have been anti-dilutive.

Restructuring and Other

Restructuring and Other	9 Months Ended
	Sep. 29, 2024
Restructuring and Related Activities [Abstract]
Restructuring and Other	P. RESTRUCTURING AND OTHER During the three months ended September 29, 2024 , Teradyne recorded restructuring and other charges primarily related to $1 .3 million of severance charges related to headcount reductions principally in Robotics. During the three months ended October 1, 2023 , Teradyne recorded restructuring and other charges primarily related to $ 4.7 million of severance charges related to headcount reductions of 94 people, principally in Semiconductor Test and Robotics, which included charges related to a voluntary early retirement program for employees meeting certain conditions, and a $ 1.5 million contract termination charge. During the nine months ended September 29, 2024 , Teradyne recorded restructuring and other charges primarily related to $ 5.3 million of severance and other charges, related to headcount reductions of 87 people primarily in Robotics and Semiconductor Test, which included charges related to a voluntary early retirement program for employees meeting certain conditions, and $ 2.2 million of acquisition and divestiture expenses related to the Technoprobe transactions. During the nine months ended October 1, 2023 , Teradyne recorded restructuring and other charges primarily related to $ 11.8 million of severance charges related to headcount reductions of 197 people, primarily in Semiconductor Test and Robotics, which included which included charges related to a voluntary early retirement program for employees meeting certain conditions, a $ 1.5 million contract termination charge, and a charge of $ 1.1 million for an increase in environmental liability.

Retirement Plans

Retirement Plans	9 Months Ended
	Sep. 29, 2024
Retirement Plans	Q. RETIREMENT PLANS ASC 715, “Compensation—Retirement Benefits,” requires an employer with defined benefit plans or other postretirement benefit plans to recognize an asset or a liability on its balance sheet for the overfunded or underfunded status of the plans as defined by ASC 715. The pension asset or liability represents a difference between the fair value of the pension plan’s assets and the projected benefit obligation at December 31. Teradyne uses a December 31 measurement date for all its plans. Defined Benefit Pension Plans Teradyne has defined benefit pension plans covering a portion of domestic employees and employees of certain non-U.S. subsidiaries. Benefits under these plans are based on employees’ years of service and compensation. Teradyne’s funding policy is to make contributions to these plans in accordance with local laws and to the extent that such contributions are tax deductible. The assets of the U.S. qualified pension plan consist primarily of fixed income and equity securities. In addition, Teradyne has an unfunded supplemental executive defined benefit plan in the United States to provide retirement benefits in excess of levels allowed by the Employment Retirement Income Security Act (“ERISA”) and the Internal Revenue Code (the “IRC”), as well as unfunded qualified foreign plans. During the three months ended September 29, 2024 , Teradyne purchased a group annuity contract for its retiree participants in the U.S. qualified pension plan. Under the group annuity, the accrued pension obligation for 132 retiree participants were transferred to an insurance company. The reduction in the pension benefit obligation and pension assets was $ 23.4 million. During the three and nine months ended September 29, 2024, Teradyne recorded settlement expense of $ 0.4 million related to the retiree group annuity transaction. In the nine months ended September 29, 2024, and October 1, 2023, Teradyne contributed $ 2.3 million and $ 2.3 million, respectively, to the U.S. supplemental executive defined benefit pension plan, and $ 0.8 million and $ 0.8 million, respectively, to certain qualified pension plans for non-U.S. subsidiaries. For the three and nine months ended September 29, 2024, and October 1, 2023, Teradyne’s net periodic pension cost was comprised of the following: For the Three Months Ended September 29, 2024 October 1, 2023 United Foreign United Foreign (in thousands) Service cost $ 216 $ 119 $ 272 $ 107 Interest cost 1,590 256 1,713 253 Expected return on plan assets ( 1,204 ) ( 23 ) ( 1,286 ) ( 11 ) Net actuarial loss (gain) ( 2,262 ) — — 66 Settlement expense 394 — — 5 Total net periodic pension cost $ ( 1,266 ) $ 352 $ 699 $ 420 For the Nine Months Ended September 29, 2024 October 1, 2023 United Foreign United Foreign (in thousands) Service cost $ 665 $ 360 $ 815 $ 320 Interest cost 4,883 766 5,138 762 Expected return on plan assets ( 3,737 ) ( 58 ) ( 3,856 ) ( 28 ) Net actuarial loss (gain) ( 2,151 ) ( 242 ) 24 66 Settlement expense 394 ( 24 ) — 5 Total net periodic pension cost $ 54 $ 802 $ 2,121 $ 1,125 Postretirement Benefit Plan In addition to receiving pension benefits, Teradyne employees in the United States who meet early retirement eligibility requirements as of their termination dates may participate in Teradyne’s Welfare Plan, which includes medical and dental benefits up to age 65. Death benefits provide a fixed sum to retirees’ survivors and are available to all retirees. Substantially all of Teradyne’s current U.S. employees could become eligible for these benefits and the existing benefit obligation relates predominantly to those employees. During the nine months ended September 29, 2024, Teradyne recorded special termination benefit charges associated with a voluntary early retirement program. For the three and nine months ended September 29, 2024, and October 1, 2023, Teradyne’s net periodic postretirement benefit cost was comprised of the following: For the Three Months For the Nine Months September 29, October 1, September 29, October 1, (in thousands) (in thousands) Service cost $ 9 $ 9 $ 28 $ 26 Interest cost 72 60 217 181 Amortization of prior service credit ( 2 ) ( 2 ) ( 7 ) ( 7 ) Special termination benefits — 1,423 462 1,792 Net actuarial loss (gain) — — ( 94 ) 30 Total net periodic postretirement benefit cost $ 79 $ 1,490 $ 606 $ 2,022

Commitments and Contingencies

Commitments and Contingencies	9 Months Ended
	Sep. 29, 2024
Commitments and Contingencies	R. COMMITMENTS AND CONTINGENCIES Purchase Commitments As of September 29, 2024 , Teradyne had entered into purchase commitments for certain components and materials. The purchase commitments covered by the agreements aggregate to approximately $ 458.1 million, of which $ 445.9 million is for less than one year. Legal Claims Teradyne is subject to various legal proceedings and claims which have arisen in the ordinary course of business such as, but not limited to, patent, employment, commercial and environmental matters. Teradyne believes that it has meritorious defenses against all pending claims and intends to vigorously contest them. While it is not possible to predict or determine the outcomes of any pending claims or to provide possible ranges of losses that may arise, Teradyne believes the potential losses associated with all of these actions are unlikely to have a material adverse effect on its business, financial position or results of operations. Guarantees and Indemnification Obligations Teradyne provides indemnification, to the extent permitted by law, to its officers, directors, employees and agents for liabilities arising from certain events or occurrences, while the officer, director, employee, or agent, is or was serving, at Teradyne’s request in such capacity. Teradyne may enter into indemnification agreements with certain of its officers and directors. With respect to acquisitions, Teradyne provides indemnifications to or assumes indemnification obligations for the current and former directors, officers and employees of the acquired companies in accordance with the acquired companies’ by-laws and charter. As a matter of practice, Teradyne has maintained directors’ and officers’ liability insurance coverage including coverage for directors and officers of acquired companies. Teradyne enters into agreements in the ordinary course of business with customers, resellers, distributors, integrators, and suppliers. Most of these agreements require Teradyne to defend and/or indemnify the other party against intellectual property infringement claims brought by a third party with respect to Teradyne’s products. From time to time, Teradyne also indemnifies customers and business partners for damages, losses and liabilities they may suffer or incur relating to personal injury, personal property damage, product liability, breach of confidentiality obligations and environmental claims relating to the use of Teradyne’s products and services or resulting from the acts or omissions of Teradyne, its employees, authorized agents or subcontractors. On occasion, Teradyne has also provided guarantees to customers regarding the delivery and performance of its products in addition to the warranty described below. As a matter of ordinary course of business, Teradyne warrants that its products will substantially perform in accordance with its standard published specifications in effect at the time of delivery. Most warranties have a one-year duration commencing from installation. A provision is recorded upon revenue recognition to cost of revenues for estimated warranty expense based upon historical experience. When Teradyne receives revenue for extended warranties beyond the standard duration, the revenue is deferred and recognized on a straight-line basis over the contract period. Related costs are expensed as incurred. As of September 29, 2024, and December 31, 2023, Teradyne had a product warranty accrual of $ 13.9 million and $ 15.7 million, respectively, included in other accrued liabilities and revenue deferrals related to extended warranties of $ 38.9 million and $ 34.9 million, respectively, included in short and long-term deferred revenue and customer advances. In addition, in the ordinary course of business, Teradyne provides minimum purchase guarantees to certain vendors to ensure continuity of supply against the market demand. Although some of these guarantees provide penalties for cancellations and/or modifications to the purchase commitments as the market demand decreases, most of the guarantees do not. Therefore, as the market demand decreases, Teradyne re-evaluates these guarantees and determines what charges, if any, should be recorded. With respect to its agreements covering product, business or entity divestitures and acquisitions, Teradyne provides certain representations, warranties and covenants to purchasers and agrees to indemnify and hold such purchasers harmless against breaches of such representations, warranties, and covenants. Many of the indemnification claims have a definite expiration date while some remain in force indefinitely. With respect to its acquisitions, Teradyne may, from time to time, assume the liability for certain events or occurrences that took place prior to the date of acquisition. As a matter of ordinary course of business, Teradyne occasionally guarantees certain indebtedness obligations of its subsidiary companies, limited to the borrowings from financial institutions, purchase commitments to certain vendors and lease commitments to landlords. Based on historical experience and information known as of September 29, 2024, and December 31, 2023 , except for product warranty, Teradyne has not recorded any liabilities for these guarantees and obligations because the amount would be immaterial.

Income Taxes

Income Taxes	9 Months Ended
	Sep. 29, 2024
Income Taxes	S. INCOME TAXES A reconciliation of the United States federal statutory corporate tax rate to Teradyne’s effective tax rate was as follows: For the Three Months For the Nine Months September 29, October 1, September 29, October 1, U.S. statutory federal tax rate 21.0 % 21.0 % 21.0 % 21.0 % Non-deductible officers' compensation 0.5 1.3 0.4 1.1 Tax credits ( 5.0 ) ( 9.3 ) ( 3.6 ) ( 5.0 ) Discrete expense (benefit) related to reserves for uncertain tax positions ( 4.9 ) 0.3 ( 2.2 ) 0.1 Foreign taxes ( 4.9 ) ( 1.5 ) ( 3.3 ) ( 1.1 ) International provisions of the U.S. Tax Cuts and Jobs Act of 2017 ( 0.8 ) ( 3.1 ) ( 1.1 ) ( 2.9 ) Other, net 1.9 2.5 0.8 0.8 Effective tax rate 7.8 % 11.2 % 12.0 % 14.0 % On a quarterly basis, Teradyne evaluates the realizability of the deferred tax assets by jurisdiction and assesses the need for a valuation allowance. As of September 29, 2024, Teradyne believes that it will ultimately realize the deferred tax assets recorded on the condensed consolidated balance sheet. However, should Teradyne believe that it is more-likely-than-not that the deferred tax assets would not be realized, the tax provision would increase in the period in which Teradyne determined that the realizability was not likely. Teradyne considers the probability of future taxable income and historical profitability, among other factors, in assessing the realizability of the deferred tax assets. As of September 29, 2024, and December 31, 2023, Teradyne had $ 7.6 million and $ 18.6 million, respectively, of reserves for uncertain tax positions. The $ 11.0 million net decrease in reserves for uncertain tax positions is related to the audit settlements. As of September 29, 2024, Teradyne estimates that it is reasonably possible that the balance of unrecognized tax benefits may decrease approximately $ 0.7 million in the next twelve months because of a lapse of statutes of limitation. The estimated decrease relates to transfer pricing and U.S. federal and state research and development credits. Teradyne recognizes interest and penalties related to income tax matters in income tax expense. As of September 29, 2024, and December 31, 2023, $ 0.2 million and $ 1.3 million, respectively, of interest and penalties were accrued for uncertain tax positions. For the nine months ended September 29, 2024, and October 1, 2023, a benefit of $ 1.0 million and expense of $ 0.2 million, respectively, were recorded for interest and penalties related to income tax items. Teradyne qualifies for a tax holiday in Singapore by fulfilling the requirements of an agreement with the Singapore Economic Development Board under which certain headcount and spending requirements must be met. The tax savings due to the tax holiday for the nine months ended September 29, 2024, were $ 10.2 million, or $ 0.06 per diluted share. The tax savings due to the tax holiday for the nine months ended October 1, 2023, were $ 1.7 million, or $ 0.01 per diluted share. In November 2020, Teradyne entered into an agreement with the Singapore Economic Development Board which extended Teradyne's Singapore tax holiday under substantially similar terms to the agreement which expired on December 31, 2020. The new tax holiday is scheduled to expire on December 31, 2025. In the nine months ended September 29, 2024 , Teradyne recognized a $ 57.5 million gain on the sale of the Device Interface Solutions business which resulted in $ 10.7 million of income tax expense that was recognized as a discrete expense during the period in which the gain occurred. On August 16, 2022, the Inflation Reduction Act of 2022 (“IRA”) was signed into law. The IRA introduced a 15 % alternative minimum tax based on the financial statement income of certain large corporations (“CAMT”), effective January 1, 2023. Teradyne currently does not expect the CAMT to have a material impact on its financial results. On December 15, 2022, the European Union ("EU") Member States formally adopted the EU’s Pillar Two Directive, which generally provides for a minimum effective tax rate of 15 %, as established by the Organization for Economic Co-operation and Development ("OECD") Pillar Two Framework. The EU’s Pillar Two Directive effective dates are January 1, 2024, and January 1, 2025, for different aspects of the directive. On July 17, 2023, the OECD published Administrative Guidance proposing certain safe harbor rules that effectively extend certain effective dates to January 1, 2027. Certain EU Member States where Teradyne has a legal presence have recently enacted the directive and administrative guidance into their local tax legislation. Additionally, countries outside the EU where Teradyne has a legal presence have enacted similar language as the EU Members States in their local tax legislation. Teradyne is closely monitoring these developments and evaluating the potential financial impact on income tax expense. As of September 29, 2024 , the effective tax rate was impacted by legislative changes that went into effect for Pillar Two in some of Teradyne's foreign jurisdictions, but it did not have a material impact on its financial statements.

Segment Information

Segment Information	9 Months Ended
	Sep. 29, 2024
Segment Reporting [Abstract]
Segment Information	T. SEGMENT INFORMATION Teradyne has four reportable segments (Semiconductor Test, System Test, Wireless Test and Robotics). Each of the reportable segments represents an individual operating segment. The Semiconductor Test segment includes operations related to the design, manufacturing and marketing of semiconductor test products and services. The System Test segment includes operations related to the design, manufacturing and marketing of products and services for storage and system level test, defense/aerospace instrumentation test, and circuit-board test. The Wireless Test segment includes operations related to the design, manufacturing and marketing of wireless test products and services. The Robotics segment includes operations related to the design, manufacturing and marketing of collaborative robotic arms, autonomous mobile robots, and advanced robotic control software. Each operating segment has a segment manager who is accountable to and maintains regular contract with Teradyne’s chief operating decision maker (Teradyne’s chief executive officer) to discuss operating activities, financial results, forecasts, and plans for the segment. Teradyne evaluates performance based on several factors, of which the primary financial measure is business segment income (loss) before income taxes. The accounting policies of the business segments are the same as those described in Note B: “Accounting Policies” in Teradyne’s Annual Report on Form 10-K for the year ended December 31, 2023. Segment information for the three and nine months ended September 29, 2024, and October 1, 2023, is as follows: Semiconductor System Robotics Wireless Segment Total Corporate Consolidated (in thousands) Three Months Ended September 29, 2024 Revenues $ 542,734 $ 73,312 $ 88,651 $ 32,601 $ 737,298 $ — $ 737,298 Income (loss) before income taxes (1)(2) 163,778 12,522 ( 24,206 ) 4,279 $ 156,373 2,611 $ 158,984 Total assets (3) 1,308,031 178,291 794,277 76,882 $ 2,357,481 1,412,247 $ 3,769,728 Three Months Ended October 1, 2023 Revenues $ 497,863 $ 83,203 $ 85,692 $ 36,974 $ 703,732 $ — $ 703,732 Income (loss) before income taxes (1)(2) 136,451 23,754 ( 21,812 ) 9,469 $ 147,862 ( 3,582 ) $ 144,280 Total assets (3) 1,382,444 178,904 684,207 92,514 $ 2,338,069 1,032,586 $ 3,370,655 Nine Months Ended September 29, 2024 Revenues $ 1,497,552 $ 209,435 $ 266,552 $ 93,457 $ 2,066,996 $ — $ 2,066,996 Income (loss) before income taxes (1)(2) 401,475 36,138 ( 56,099 ) 13,355 $ 394,869 56,420 $ 451,289 Total assets (3) 1,308,031 178,291 794,277 76,882 $ 2,357,481 1,412,247 $ 3,769,728 Nine Months Ended October 1, 2023 Revenues $ 1,387,580 $ 252,106 $ 246,541 $ 119,472 $ 2,005,699 $ — $ 2,005,699 Income (loss) before income taxes (1)(2) 361,676 67,629 ( 66,704 ) 30,841 $ 393,442 ( 7,675 ) $ 385,767 Total assets (3) 1,382,444 178,904 684,207 92,514 $ 2,338,069 1,032,586 $ 3,370,655 (1) Included in Corporate and Eliminations are interest income, interest expense, net foreign exchange gains (losses), intercompany eliminations, severance charges, pension, acquisition and divestiture related fees, and an expense for the modification of outstanding equity awards. (2) Included in income (loss) before taxes are charges related to restructuring and other, expense for the modification of outstanding equity awards, legal settlement, pension mark-to-market, and inventory charges. (3) Total assets are attributable to each segment. Corporate assets consist of cash and cash equivalents, marketable securities, and certain other assets. Included in each segment are charges and credits in the following line items in the statements of operations: For the Three Months For the Nine Months September 29, October 1, September 29, October 1, (in thousands) (in thousands) Semiconductor Test: Cost of revenues—inventory charge $ 4,041 $ 10,422 $ 11,405 $ 18,374 Restructuring and other—employee severance — 1,776 1,277 5,055 System Test: Cost of revenues—inventory charge $ — $ — $ 1,016 $ 1,412 Restructuring and other—employee severance — — — 1,124 Robotics: Cost of revenues—legal settlement $ 3,600 $ — $ 3,600 $ — Restructuring and other—employee severance 1,110 636 2,647 2,707 Cost of revenues—inventory charge 537 652 1,071 2,203 Wireless: Cost of revenues—inventory charge $ 1,204 $ — $ 2,024 $ 1,080 Corporate and Eliminations: Restructuring and other—acquisition & divestiture related expenses $ — $ — $ 2,214 $ — Selling and administrative —equity modification — — 1,469 5,889 Restructuring and other—employee severance — 1,753 — 2,877 Restructuring and other—contract termination — 1,511 — 1,511 Restructuring and other—other 2,437 — 2,437 1,100

Shareholders' Equity

Shareholders' Equity	9 Months Ended
	Sep. 29, 2024
Equity [Abstract]
Shareholders' Equity	U. SHAREHOLDERS’ EQUITY Stock Repurchase Program In January 2023, Teradyne’s Board of Directors cancelled its January 2021 repurchase program and approved a new repurchase program for up to $ 2.0 billion of common stock. As of January 1, 2023, share repurchases in excess of issuances are subject to a 1 % excise tax, which is included as part of the cost basis of the shares acquired. In 2024, Teradyne intends, based on market conditions, to repurchase its common stock in an amount necessary to offset dilution from equity compensation and our employee share purchase program. During the nine months ended September 29, 2024, Teradyne repurchased 0.5 million shares of common stock for a total cost of $ 55.1 million at an average price of $ 111.32 per share. The cumulative repurchases under the January 2023 repurchase program as of September 29, 2024, were 4.4 million shares of common stock for $ 455.6 million at an average price per share of $ 103.46 . During the nine months ended October 1, 2023 , Teradyne repurchased 3.4 million shares of common stock for a total cost of $ 349.3 million at an average price of $ 103.89 per share. The total cost of shares acquired includes commissions and related excise tax and is recorded as a reduction to retained earnings. Dividend Holders of Teradyne’s common stock are entitled to receive dividends when they are declared by Teradyne’s Board of Directors. In January 2024, May 2024, and August 2024 , Teradyne’s Board of Directors declared a quarterly cash dividend of $ 0.12 per share. Dividend payments for the three and nine months ended September 29, 2024, were $ 19.6 million and $ 57.0 million , respectively. In January 2023, May 2023, and August 2023 , Teradyne’s Board of Directors declared a quarterly cash dividend of $ 0.11 per share. Dividend payments for the three and nine months ended October 1, 2023, were $ 16.9 million and $ 51.1 million , respectively.

Accounting Policies (Policies)

Accounting Policies (Policies)	9 Months Ended
	Sep. 29, 2024
Basis of Presentation	Basis of Presentation The consolidated interim financial statements include the accounts of Teradyne and its wholly owned subsidiaries. All significant intercompany balances and transactions have been eliminated. These interim financial statements are unaudited and reflect all normal recurring adjustments that are, in the opinion of management, necessary for the fair statement of such interim financial statements. The December 31, 2023, condensed consolidated balance sheet data was derived from audited financial statements but does not include all disclosures required by United States of America generally accepted accounting principles (“U.S. GAAP”) for complete financial statements. The accompanying financial information should be read in conjunction with the consolidated financial statements and notes thereto contained in Teradyne’s Annual Report on Form 10-K, filed with the U.S. Securities and Exchange Commission (“SEC”) on February 22, 2024, for the year ended December 31, 2023 .
Preparation of Financial Statements and Use of Estimates	Preparation of Financial Statements and Use of Estimates The preparation of consolidated financial statements requires management to make estimates and judgments that affect the reported amounts of assets, liabilities, revenues and expenses, and related disclosure of contingent liabilities. On an on-going basis, management evaluates its estimates, including those related to inventories, investments, goodwill, intangible and other long-lived assets, accounts receivable, income taxes, deferred tax assets and liabilities, pensions, warranties, contingent consideration liabilities, and loss contingencies. Management bases its estimates on historical experience and on appropriate and customary assumptions that are believed to be reasonable under the circumstances, the results of which form the basis for making judgments about the carrying values of assets and liabilities that are not readily apparent from other sources. Management is not aware of any specific event or circumstance that would require an update to its estimates or judgments or a revision of the carrying value of its assets or liabilities as of the date of issuance of this Quarterly Report on Form 10-Q. These estimates may change, as new events occur, and additional information is obtained. Actual results may differ significantly from these estimates under different assumptions or conditions.
Equity Method Investments	Equity Method Investments Teradyne accounts for investments using the equity method of accounting when it has significant influence over the financial and operating policies, but not control, of the investee. The equity method investments are initially recorded at cost and included in ‘Equity method investment’ in the consolidated balance sheet. Teradyne records its share of investee's net income or loss and other comprehensive income, and the amortization of equity method basis difference, calculated as the difference between the investment and the amount of underlying equity in net assets acquired, on a 3-month lag, which is applied consistently from period to period. Teradyne's share of investee's net income and the amortization of equity method basis difference are reported in ‘Equity in net earnings of affiliate’ in the consolidated statement of operations. Teradyne includes its share of investee's other comprehensive income and a cumulative translation adjustment in the consolidated statements of comprehensive income. Teradyne monitors on an ongoing basis its equity method investments for indicators of other-than-temporary declines in fair value below carrying value.

Revenue (Tables)

Revenue (Tables)	9 Months Ended
	Sep. 29, 2024
Revenue from Contract with Customer [Abstract]
Disaggregated Revenue by Primary Geographical Market, Major Product Line and Timing of Revenue Recognition	The following table provides information about disaggregated revenue by timing of revenue recognition, primary geographical market, and major product lines. Semiconductor Test System Test Robotics Wireless Test System Memory Universal Mobile Total (in thousands) For the Three Months Ended September 29, 2024 (1) Timing of Revenue Recognition Point in Time $ 323,507 $ 143,581 $ 55,611 $ 71,607 $ 15,065 $ 29,465 $ 638,836 Over Time 68,848 6,798 17,701 1,811 168 3,136 98,462 Total $ 392,355 $ 150,379 $ 73,312 $ 73,418 $ 15,233 $ 32,601 $ 737,298 Geographical Market Asia Pacific $ 364,476 $ 137,890 $ 29,277 $ 10,873 $ 2,960 $ 24,342 $ 569,818 Americas 17,150 1,325 39,919 32,315 8,460 5,515 104,684 Europe, Middle East and Africa 10,729 11,164 4,116 30,230 3,813 2,744 62,796 Total $ 392,355 $ 150,379 $ 73,312 $ 73,418 $ 15,233 $ 32,601 $ 737,298 For the Three Months Ended October 1, 2023 (1) Timing of Revenue Recognition Point in Time $ 330,846 $ 86,247 $ 66,418 $ 68,938 $ 14,012 $ 32,638 $ 599,099 Over Time 73,264 7,506 16,785 1,607 1,135 4,336 104,633 Total $ 404,110 $ 93,753 $ 83,203 $ 70,545 $ 15,147 $ 36,974 $ 703,732 Geographical Market Asia Pacific $ 360,375 $ 91,352 $ 40,464 $ 15,430 $ 3,180 $ 24,727 $ 535,528 Americas 24,752 1,356 35,888 26,073 7,154 10,139 105,362 Europe, Middle East and Africa 18,983 1,045 6,851 29,042 4,813 2,108 62,842 Total $ 404,110 $ 93,753 $ 83,203 $ 70,545 $ 15,147 $ 36,974 $ 703,732 For the Nine Months Ended September 29, 2024 (2) Timing of Revenue Recognition Point in Time $ 896,635 $ 367,679 $ 157,203 $ 210,222 $ 49,850 $ 82,652 $ 1,764,241 Over Time 211,612 21,626 52,232 5,542 938 10,805 302,755 Total $ 1,108,247 $ 389,305 $ 209,435 $ 215,764 $ 50,788 $ 93,457 $ 2,066,996 Geographical Market Asia Pacific $ 1,016,674 $ 357,993 $ 76,317 $ 37,254 $ 11,361 $ 70,776 $ 1,570,375 Americas 59,912 13,631 105,197 82,220 28,195 16,240 305,395 Europe, Middle East and Africa 31,661 17,681 27,921 96,290 11,232 6,441 191,226 Total $ 1,108,247 $ 389,305 $ 209,435 $ 215,764 $ 50,788 $ 93,457 $ 2,066,996 For the Nine Months Ended October 1, 2023 (2) Timing of Revenue Recognition Point in Time $ 886,201 $ 260,052 $ 200,076 $ 194,698 $ 42,748 $ 108,262 $ 1,692,038 Over Time 219,436 21,890 52,030 5,731 3,364 11,210 313,661 Total $ 1,105,638 $ 281,942 $ 252,106 $ 200,429 $ 46,112 $ 119,472 $ 2,005,699 Geographical Market Asia Pacific $ 946,696 $ 270,297 $ 121,698 $ 43,530 $ 6,973 $ 70,320 $ 1,459,514 Americas 98,511 8,586 105,031 69,346 25,051 42,476 349,001 Europe, Middle East and Africa 60,431 3,059 25,377 87,553 14,088 6,676 197,184 Total $ 1,105,638 $ 281,942 $ 252,106 $ 200,429 $ 46,112 $ 119,472 $ 2,005,699 (1) Include s $ 0.8 million and $ 1.4 million in 2024, and 2023, respectively, for leases of Teradyne’s systems recognized outside Accounting Standards Codification (“ASC”) 606 “Revenue from Contracts with Customers.” (2) Includes $ 2.5 million and $ 3.9 million in 2024 and 2023, respectively, for leases of Teradyne’s systems recognized outside Accounting Standards Codification (“ASC”) 606 “Revenue from Contracts with Customers.”
Deferred Revenue and Customer Advances	Deferred revenue and customer advances consist of the following and are included in short and long-term deferred revenue and customer advances on the balance sheet: September 29, December 31, (in thousands) Maintenance, service and training $ 57,866 $ 66,458 Customer advances, undelivered elements and other 44,116 35,731 Extended warranty 38,929 34,897 Total deferred revenue and customer advances $ 140,911 $ 137,086

Dispositions (Tables)

Dispositions (Tables)	9 Months Ended
	Sep. 29, 2024
Device Interface Solutions [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Schedule of Assets and Liabilities Related to the DIS Sale Agreement	Assets and liabilities related to the DIS sale agreement met the criteria and were classified as held for sale in Teradyne’s consolidated balance sheet as of December 31, 2023, as follows: December 31, Current assets: Inventories, net $ 17,952 Prepayments 5,298 Total current assets held for sale 23,250 Property, plant and equipment, net 8,986 Operating lease right-of-use assets, net 2,545 Total assets held for sale $ 34,781 Current liabilities: Accounts payable $ 6,356 Other accrued liabilities 552 Operating lease liabilities 471 Total current liabilities held for sale 7,379 Long-term operating lease liabilities 2,000 Total liabilities held for sale $ 9,379 Net assets held for sale $ 25,402

Equity Method Investment (Table

Equity Method Investment (Tables)	9 Months Ended
	Sep. 29, 2024
Equity Method Investments and Joint Ventures [Abstract]
Summary of Equity Method Investment	(in thousands) Balance at June 30, 2024 $ 524,060 Other comprehensive income related to investment 15,366 Equity in net earnings of affiliate ( 1,075 ) Balance at September 29, 2024 $ 538,351

Inventories (Tables)

Inventories (Tables)	9 Months Ended
	Sep. 29, 2024
Composition of Inventories, Net	Inventories, net consisted of the following at September 29, 2024, and December 31, 2023: September 29, December 31, (in thousands) Raw material $ 216,019 $ 258,422 Work-in-process 48,249 26,851 Finished goods 33,072 24,701 Total inventories, net (1) $ 297,340 $ 309,974 (1) Inventories, net at December 31, 2023, exclude $ 18.0 million of primarily work-in-process inventories, net classified as assets held for sale. See Note E: "Dispositions" for additional information.

Financial Instruments (Tables)

Financial Instruments (Tables)	9 Months Ended
	Sep. 29, 2024
Schedule of Fair Value of Financial Assets and Liabilities Measured on Recurring Basis	The following tables set forth by fair value hierarchy Teradyne’s financial assets and liabilities that were measured at fair value on a recurring basis as of September 29, 2024, and December 31, 2023. September 29, 2024 Quoted Prices Significant Significant Total (in thousands) Assets Cash $ 198,946 $ — $ — $ 198,946 Cash equivalents 308,000 3,090 — 311,090 Available-for-sale securities: U.S. Treasury securities — 41,833 — 41,833 Corporate debt securities — 37,149 — 37,149 Certificates of deposit and time deposits — 21,741 — 21,741 Debt mutual funds 8,640 — — 8,640 U.S. government agency securities — 3,931 — 3,931 Non-U.S. government securities — 801 — 801 Equity securities: Mutual funds 53,480 — — 53,480 $ 569,066 $ 108,545 $ — $ 677,611 Derivative assets — 332 — 332 Total $ 569,066 $ 108,877 $ — $ 677,943 Liabilities Derivative liabilities — 1,435 — $ 1,435 Total $ — $ 1,435 $ — $ 1,435 Reported as follows: (Level 1) (Level 2) (Level 3) Total (in thousands) Assets Cash and cash equivalents $ 506,946 $ 3,090 $ — $ 510,036 Marketable securities — 41,631 — 41,631 Long-term marketable securities 62,120 63,824 — 125,944 Other current assets — 332 — 332 Total $ 569,066 $ 108,877 $ — $ 677,943 Liabilities Other current liabilities — 1,435 — 1,435 Total $ — $ 1,435 $ — $ 1,435 December 31, 2023 Quoted Prices Significant Significant Total (in thousands) Assets Cash $ 298,156 $ — $ — $ 298,156 Cash equivalents 453,298 6,117 — 459,415 Available-for-sale securities: Corporate debt securities — 52,734 — 52,734 U.S. Treasury securities — 41,808 — 41,808 Certificates of deposit and time deposits — 21,772 — 21,772 Debt mutual funds 8,773 — — 8,773 U.S. government agency securities — 4,892 — 4,892 Commercial paper — 1,667 — 1,667 Non-U.S. government securities — 810 — 810 Equity securities: Mutual Funds 47,132 — — 47,132 $ 807,359 $ 129,800 $ — $ 937,159 Derivative assets — 18,746 — 18,746 Total $ 807,359 $ 148,546 $ — $ 955,905 Liabilities Derivative liabilities — 2,545 — 2,545 Total $ — $ 2,545 $ — $ 2,545 Reported as follows: (Level 1) (Level 2) (Level 3) Total (in thousands) Assets Cash and cash equivalents $ 751,454 $ 6,117 $ — $ 757,571 Marketable securities — 62,154 — 62,154 Long-term marketable securities 55,905 61,529 — 117,434 Other current assets — 18,746 — 18,746 Total $ 807,359 $ 148,546 $ — $ 955,905 Liabilities Other current liabilities $ — $ 2,545 $ — $ 2,545 Total $ — $ 2,545 $ — $ 2,545
Schedule of Carrying Amounts and Fair Values of Financial Instruments	The carrying amounts and fair values of Teradyne’s financial instruments at September 29, 2024, and December 31, 2023, were as follows: September 29, 2024 December 31, 2023 Carrying Value Fair Value Carrying Value Fair Value (in thousands) Assets Cash and cash equivalents $ 510,036 $ 510,036 $ 757,571 $ 757,571 Marketable securities 167,575 167,575 179,588 179,588 Derivative assets 332 332 18,746 18,746 Liabilities Derivative liabilities 1,435 1,435 2,545 2,545
Schedule of Available-for-Sale Marketable Securities	The following table summarizes the composition of available-for-sale marketable securities at September 29, 2024: September 29, 2024 Available-for-Sale Cost Unrealized Unrealized Fair Fair Market (in thousands) U.S. Treasury securities $ 45,522 $ 106 $ ( 3,795 ) $ 41,833 $ 22,985 Corporate debt securities $ 39,986 $ 323 $ ( 3,160 ) $ 37,149 $ 25,248 Certificates of deposit and time deposits 21,741 — — 21,741 — Debt mutual funds 8,846 — ( 206 ) 8,640 3,319 U.S. government agency securities 3,921 11 ( 1 ) 3,931 876 Non-U.S. government securities 801 — — 801 — $ 120,817 $ 440 $ ( 7,162 ) $ 114,095 $ 52,428 Reported as follows: Cost Unrealized Unrealized Fair Fair Market (in thousands) Marketable securities $ 41,673 20 $ ( 62 ) $ 41,631 $ 9,973 Long-term marketable securities 79,144 420 ( 7,100 ) 72,464 42,455 $ 120,817 $ 440 $ ( 7,162 ) $ 114,095 $ 52,428 The following table summarizes the composition of available-for-sale marketable securities at December 31, 2023: December 31, 2023 Available-for-Sale Cost Unrealized Unrealized Fair Fair Market (in thousands) Corporate debt securities $ 56,458 $ 201 $ ( 3,925 ) $ 52,734 $ 44,263 U.S. Treasury securities 45,725 14 ( 3,931 ) 41,808 35,080 Certificates of deposit and time deposits 21,772 — — 21,772 — Debt mutual funds 9,081 — ( 308 ) 8,773 3,303 U.S. government agency securities 4,898 — ( 6 ) 4,892 4,892 Commercial paper 1,633 34 — 1,667 — Non-U.S. government securities 810 — — 810 — $ 140,377 $ 249 $ ( 8,170 ) $ 132,456 $ 87,538 Reported as follows: Cost Unrealized Unrealized Fair Fair Market (in thousands) Marketable securities $ 62,385 $ 36 $ ( 267 ) 62,154 $ 34,844 Long-term marketable securities 77,992 213 ( 7,903 ) 70,302 52,694 $ 140,377 $ 249 $ ( 8,170 ) $ 132,456 $ 87,538
Contractual Maturities of Investments Held	The contractual maturities of investments in available-for-sale securities held at September 29, 2024, were as follows: September 29, 2024 Cost Fair Market (in thousands) Due within one year $ 41,673 $ 41,631 Due after 1 year through 5 years 25,690 25,729 Due after 5 years through 10 years 7,950 7,908 Due after 10 years 36,658 30,187 Total $ 111,971 $ 105,455
Schedule of Notional Amount of Derivatives	At September 29, 2024, and December 31, 2023, Teradyne had the following contracts to buy and sell non-U.S. currencies for U.S. dollars and other non-U.S. currencies with the following notional amounts: Net Notional Value September 29, December 31, (in millions) Currency Hedged (Buy/Sell) U.S. dollar/Taiwan dollar 29.6 42.7 U.S. dollar/Japanese yen 21.7 11.0 U.S. dollar/Korean won 8.9 7.2 U.S. dollar/British pound sterling 1.0 1.5 U.S. dollar/Danish krone — 36.0 Danish krone/U.S. dollar 25.7 0.7 Euro/U.S. dollar 24.8 25.3 Singapore dollar/U.S. dollar 23.0 16.6 Philippine peso/U.S. dollar 9.7 10.1 Chinese yuan/U.S. dollar 1.7 1.0 Total $ 146.1 $ 152.1
Schedule of Foreign Currency Cash Flow Hedges	At September 29, 2024, and December 31, 2023, Teradyne had the following cash flow hedge contracts to buy and sell non-U.S. currencies for U.S. dollars with the following notional amounts: Net Notional Value September 29, December 31, (in millions) Currency Hedged (Buy/Sell) U.S. dollar/Japanese yen $ 12.1 $ 35.5 Total $ 12.1 $ 35.5
Schedule of Derivative Instruments in Statement of Financial Position at Fair Value	The following table summarizes the fair value of derivative instruments as of September 29, 2024, and December 31, 2023: Balance Sheet Location September 29, December 31, (in thousands) Derivatives not designated as hedging instruments: Foreign exchange forward contracts Other current assets 332 733 Foreign exchange forward contracts Other current liabilities ( 1,102 ) ( 2,545 ) Foreign exchange option contracts Other current assets — 17,364 Derivatives designated as hedging instruments: Foreign exchange forward contracts Other current assets — 648 Foreign exchange forward contracts Other current liabilities ( 333 ) — Total derivatives $ ( 1,103 ) $ 16,200
Schedule of Effect of Derivative Instruments on Statement of Operations Recognized	The following table summarizes the effect of derivative instruments recognized in the statement of operations for the three and nine months ended September 29, 2024, and October 1, 2023: For the Three Months For the Nine Months Location of (Gains) Losses September 29, October 1, September 29, October 1, (in thousands) (in thousands) Derivatives not designated as hedging instruments: Foreign exchange forward contracts (1) Other (income) expense, net $ 4,829 $ ( 1,886 ) $ 686 $ ( 4,667 ) Foreign exchange option contracts Other (income) expense, net — — 9,764 — Derivatives designated as hedging instruments: Foreign exchange forward and option contracts Revenue — ( 3,960 ) ( 2,280 ) ( 2,008 ) Total Derivatives $ 4,829 $ ( 5,846 ) $ 8,170 $ ( 6,675 ) (1) The table does not reflect the corresponding gains and losses from the remeasurement of the monetary assets and liabilities denominated in foreign currencies. For the three and nine months ended September 29, 2024, net losses (gains) from remeasurement of monetary assets and liabilities denominated in foreign currencies were $ ( 2.9 ) million and $ 3.1 million, respectively. For the three and nine months ended October 1, 2023, net losses from remeasurement of monetary assets and liabilities denominated in foreign currencies were $ 5.3 million and $ 12.3 million, respectively.

Debt (Tables)

Debt (Tables)	9 Months Ended
	Sep. 29, 2024
Schedule of Interest Expense on Teradyne's Senior Notes	The interest expense on Teradyne's senior notes for three and nine months ended October 1, 2023, was as follows: For the Three Months For the Nine Months September 29, October 1, September 29, October 1, (in thousands) (in thousands) Contractual interest expense on the coupon $ — $ 74 $ — $ 312 Amortization of debt issuance fees recognized as interest expense — — — 113 Total interest expense on the convertible debt $ — $ 74 $ — $ 425

Prepayments (Tables)

Prepayments (Tables)	9 Months Ended
	Sep. 29, 2024
Prepayments [Abstract]
Schedule of Prepayments and other assets	Prepayments consist of the following: September 29, December 31, (in thousands) Contract manufacturer and supplier prepayments $ 439,647 $ 502,257 Prepaid taxes 20,734 16,083 Prepaid maintenance and other services 19,040 17,592 Other prepayments 10,127 13,038 Total prepayments (1) $ 489,548 $ 548,970 (1) Exclude s $ 5.3 million at December 31, 2023 , of contract manufacturer and supplier prepayments, classified as assets held for sale. See Note E: “Dispositions” for additional information.

Product Warranty (Tables)

Product Warranty (Tables)	9 Months Ended
	Sep. 29, 2024
Other Accrued Liabilities	Related costs are charged to the warranty accrual as incurred. The balance below is included in other accrued liabilities. For the Three Months For the Nine Months September 29, October 1, September 29, October 1, (in thousands) (in thousands) Balance at beginning of period $ 15,244 $ 12,543 $ 15,698 $ 14,181 Accruals for warranties issued during the period 2,149 8,859 8,331 16,237 Accruals related to pre-existing warranties ( 545 ) ( 795 ) ( 1,513 ) ( 1,552 ) Settlements made during the period ( 2,990 ) ( 5,892 ) ( 8,658 ) ( 14,151 ) Balance at end of period $ 13,858 $ 14,715 $ 13,858 $ 14,715
Extended Product Warranty of Short and Long-Term Deferred Revenue and Customer Advances	Related costs are expensed as incurred. The balance below is included in short and long-term deferred revenue and customer advances. For the Three Months For the Nine Months September 29, October 1, September 29, October 1, (in thousands) (in thousands) Balance at beginning of period $ 33,512 $ 44,422 $ 34,897 $ 56,180 Deferral of new extended warranty revenue 9,714 2,734 22,316 11,615 Recognition of extended warranty deferred revenue ( 4,297 ) ( 8,313 ) ( 18,284 ) ( 28,952 ) Balance at end of period $ 38,929 $ 38,843 $ 38,929 $ 38,843

Stock-Based Compensation (Table

Stock-Based Compensation (Tables)	9 Months Ended
	Sep. 29, 2024
Schedule of Estimated Fair Value of TSR Performance-Based Restricted Stock Unit Awards Assumptions	The grant date fair value was estimated using the Monte Carlo simulation model with the following assumptions: For the Nine Months September 29, October 1, Risk-free interest rate 3.9 % 4.0 % Teradyne volatility-historical 42.4 % 49.7 % NYSE Composite Index volatility-historical 15.6 % 24.1 % Dividend yield 0.5 % 0.4 %
Fair Value of Stock Options Using Assumptions	The fair value of stock options was estimated using the Black-Scholes option-pricing model with the following assumptions: For the Nine Months September 29, October 1, Expected life (years) 4.0 4.0 Risk-free interest rate 4.0 % 3.8 % Volatility-historical 46.3 % 46.6 % Dividend yield 0.5 % 0.4 %

Accumulated Other Comprehensi_2

Accumulated Other Comprehensive Income (Loss) (Tables)	9 Months Ended
	Sep. 29, 2024
Changes in Accumulated Other Comprehensive Income (Loss)	Changes in accumulated other comprehensive income (loss), which are presented net of tax, consist of the following: Foreign Unrealized Unrealized (Losses) Gains on Cash Flow Hedges Retirement Total (in thousands) Nine Months Ended September 29, 2024 Balance at December 31, 2023, net of tax of $ 0 , $( 1,728 ), $ 142 , $( 1,132 ), respectively $ ( 22,442 ) $ ( 6,194 ) $ 506 $ 1,152 $ ( 26,978 ) Other comprehensive (loss) gain before reclassifications, net of tax of $ 0 , $ 205 , $ 285 , $ 0 , respectively 22,751 885 1,014 — 24,650 Amounts reclassified from accumulated other comprehensive income (loss), net of tax of $ 0 , $ 24 , $( 500 ), $( 1 ), respectively — 86 ( 1,780 ) ( 6 ) ( 1,700 ) Net current period other comprehensive (loss) gain, net of tax of $ 0 , $ 229 , $( 215 ), $( 1 ), respectively 22,751 971 ( 766 ) ( 6 ) 22,950 Balance at September 29, 2024, net of tax of $ 0 , $( 1,499 ), $( 73 ), $( 1,133 ), respectively $ 309 $ ( 5,223 ) $ ( 260 ) $ 1,146 $ ( 4,028 ) Nine Months Ended October 1, 2023 Balance at December 31, 2022, net of tax of $ 0 , $( 2,308 ), $( 708 ), $( 1,130 ), respectively $ ( 39,849 ) $ ( 8,661 ) $ ( 2,517 ) $ 1,159 $ ( 49,868 ) Other comprehensive (loss) gain before reclassifications, net of tax of $ 0 , $( 408 ), $ 1,816 , $ 0 , respectively ( 2,073 ) ( 903 ) 6,456 — 3,480 Amounts reclassified from accumulated other comprehensive income (loss), net of tax of $ 0 , $ 9 , $( 441 ), $( 1 ), respectively — 33 ( 1,567 ) ( 6 ) ( 1,540 ) Net current period other comprehensive (loss) gain, net of tax of $ 0 , $( 399 ), $ 1,375 , $( 1 ), respectively ( 2,073 ) ( 870 ) 4,889 ( 6 ) 1,940 Balance at October 1, 2023, net of tax of $ 0 , $( 2,707 ), $ 667 , $( 1,131 ), respectively $ ( 41,922 ) $ ( 9,531 ) $ 2,372 $ 1,153 $ ( 47,928 )
Reclassifications Out of Accumulated Other Comprehensive Income (Loss) to Statements of Operations	Reclassifications out of accumulated other comprehensive income (loss) to the statement of operations for the three and nine months ended September 29, 2024, and October 1, 2023, were as follows: Details about Accumulated Other Comprehensive Income (Loss) Components For the Three Months For the Nine Months Affected Line Item September 29, October 1, September 29, October 1, (in thousands) (in thousands) Available-for-sale marketable securities: Unrealized (losses) gains, net of tax of $ 2 , $ 0 , $( 24 ), $( 9 ), respectively $ 7 $ — $ ( 86 ) $ ( 33 ) Other (income) expense, net Cash flow hedges: Unrealized (losses) gains, net of tax of $ 0 , $ 869 , $ 500 , $ 441 , respectively — 3,091 1,780 1,567 Revenue Defined benefit pension and postretirement plans: Amortization of prior service credit, net of tax of $ 0 , $ 0 , $ 1 , $ 1 , respectively 2 2 6 6 (a) Total reclassifications, net of tax of $ 2 , $ 869 , $ 477 , $ 433 respectively $ 9 $ 3,093 $ 1,700 $ 1,540 Net income (a) The amortization of prior service credit is included in the computation of net periodic postretirement benefit cost. See Note Q: “Retirement Plans.”

Goodwill and Acquired Intangi_2

Goodwill and Acquired Intangible Assets (Tables)	9 Months Ended
	Sep. 29, 2024
Changes in Carrying Amount of Goodwill by Segment	The changes in the carrying amount of goodwill by reportable segments for the nine months ended September 29, 2024, were as follows: Robotics Wireless Semiconductor System Total (in thousands) Balance at December 31, 2023 Goodwill $ 395,463 $ 361,819 $ 262,237 $ 158,699 $ 1,178,218 Accumulated impairment losses — ( 353,843 ) ( 260,540 ) ( 148,183 ) ( 762,566 ) Total Goodwill 395,463 7,976 1,697 10,516 415,652 Foreign currency translation adjustment 3,765 — ( 5 ) — 3,760 Balance at September 29, 2024 Goodwill $ 399,229 $ 361,819 $ 262,232 $ 158,699 1,181,978 Accumulated impairment losses — ( 353,843 ) ( 260,540 ) ( 148,183 ) ( 762,566 ) Total Goodwill $ 399,229 $ 7,976 $ 1,692 $ 10,516 $ 419,412
Schedule of Amortizable Intangible Assets	Amortizable intangible assets consist of the following and are included in intangible assets, net on the balance sheet: Gross Accumulated Foreign Net (in thousands) Balance at September 29, 2024 Developed technology $ 267,706 $ ( 252,406 ) $ ( 5,337 ) $ 9,963 Customer relationships 52,109 ( 49,134 ) 210 3,185 Tradenames and trademarks 59,007 ( 49,618 ) ( 1,249 ) 8,140 Total intangible assets $ 378,822 $ ( 351,158 ) $ ( 6,376 ) $ 21,288 Balance at December 31, 2023 Developed technology $ 267,706 $ ( 243,191 ) $ ( 5,343 ) $ 19,172 Customer relationships 52,109 ( 47,850 ) 232 4,491 Tradenames and trademarks 59,007 ( 46,021 ) ( 1,245 ) 11,741 Total intangible assets $ 378,822 $ ( 337,062 ) $ ( 6,356 ) $ 35,404
Schedule of Estimated Intangible Assets Amortization Expense	Estimated intangible asset amortization expense for each of the five succeeding fiscal years and thereafter is as follows: Year Amortization (in thousands) 2024 $ 4,775 2025 11,454 2026 2,402 2027 1,185 2028 1,104 Thereafter 368

Net Income Per Common Share (Ta

Net Income Per Common Share (Tables)	9 Months Ended
	Sep. 29, 2024
Computation of Basic and Diluted Net Income (Loss) Per Common Share	The following table sets forth the computation of basic and diluted net income per common share: For the Three Months For the Nine Months September 29, October 1, September 29, October 1, (in thousands, except per share amounts) (in thousands, except per share amounts) Net income for basic and diluted net income per share $ 145,649 $ 128,116 $ 396,119 $ 331,698 Weighted average common shares-basic 163,002 153,762 157,951 154,809 Effect of dilutive potential common shares: Restricted stock units 768 455 637 410 Convertible note hedge warrant shares (1) 460 9,168 4,751 9,009 Stock options 13 26 13 39 Employee stock purchase plan 10 10 5 8 Incremental shares from assumed conversion of convertible notes (2) — 629 — 762 Dilutive potential common shares 1,251 10,288 5,406 10,228 Weighted average common shares-diluted 164,253 164,050 163,357 165,037 Net income per common share-basic $ 0.89 $ 0.83 $ 2.51 $ 2.14 Net income per common share-diluted $ 0.89 $ 0.78 $ 2.42 $ 2.01 (1) Convertible notes hedge warrant shares were calculated using the difference between the average Teradyne stock price for the period and the warrant price, multiplied by the number of warrant shares. The result of this calculation, representing the total intrinsic value of the warrant, was divided by the average Teradyne stock price for the period. (2) Incremental shares from assumed conversion of the convertible notes were calculated using the difference between the average Teradyne stock price for the period and the conversion price, multiplied by the number of convertible notes shares. The result of this calculation, representing the total intrinsic value of the convertible notes, was divided by the average Teradyne stock price for the period.

Retirement Plans (Tables)

Retirement Plans (Tables)	9 Months Ended
	Sep. 29, 2024
Defined Benefit Pension Plans
Net Periodic Pension and Postretirement Benefit Costs	For the three and nine months ended September 29, 2024, and October 1, 2023, Teradyne’s net periodic pension cost was comprised of the following: For the Three Months Ended September 29, 2024 October 1, 2023 United Foreign United Foreign (in thousands) Service cost $ 216 $ 119 $ 272 $ 107 Interest cost 1,590 256 1,713 253 Expected return on plan assets ( 1,204 ) ( 23 ) ( 1,286 ) ( 11 ) Net actuarial loss (gain) ( 2,262 ) — — 66 Settlement expense 394 — — 5 Total net periodic pension cost $ ( 1,266 ) $ 352 $ 699 $ 420 For the Nine Months Ended September 29, 2024 October 1, 2023 United Foreign United Foreign (in thousands) Service cost $ 665 $ 360 $ 815 $ 320 Interest cost 4,883 766 5,138 762 Expected return on plan assets ( 3,737 ) ( 58 ) ( 3,856 ) ( 28 ) Net actuarial loss (gain) ( 2,151 ) ( 242 ) 24 66 Settlement expense 394 ( 24 ) — 5 Total net periodic pension cost $ 54 $ 802 $ 2,121 $ 1,125
Postretirement Benefit Plans
Net Periodic Pension and Postretirement Benefit Costs	For the three and nine months ended September 29, 2024, and October 1, 2023, Teradyne’s net periodic postretirement benefit cost was comprised of the following: For the Three Months For the Nine Months September 29, October 1, September 29, October 1, (in thousands) (in thousands) Service cost $ 9 $ 9 $ 28 $ 26 Interest cost 72 60 217 181 Amortization of prior service credit ( 2 ) ( 2 ) ( 7 ) ( 7 ) Special termination benefits — 1,423 462 1,792 Net actuarial loss (gain) — — ( 94 ) 30 Total net periodic postretirement benefit cost $ 79 $ 1,490 $ 606 $ 2,022

Income Taxes (Tables)

Income Taxes (Tables)	9 Months Ended
	Sep. 29, 2024
Reconciliation of Effective Tax Rate	A reconciliation of the United States federal statutory corporate tax rate to Teradyne’s effective tax rate was as follows: For the Three Months For the Nine Months September 29, October 1, September 29, October 1, U.S. statutory federal tax rate 21.0 % 21.0 % 21.0 % 21.0 % Non-deductible officers' compensation 0.5 1.3 0.4 1.1 Tax credits ( 5.0 ) ( 9.3 ) ( 3.6 ) ( 5.0 ) Discrete expense (benefit) related to reserves for uncertain tax positions ( 4.9 ) 0.3 ( 2.2 ) 0.1 Foreign taxes ( 4.9 ) ( 1.5 ) ( 3.3 ) ( 1.1 ) International provisions of the U.S. Tax Cuts and Jobs Act of 2017 ( 0.8 ) ( 3.1 ) ( 1.1 ) ( 2.9 ) Other, net 1.9 2.5 0.8 0.8 Effective tax rate 7.8 % 11.2 % 12.0 % 14.0 %

Segment Information (Tables)

Segment Information (Tables)	9 Months Ended
	Sep. 29, 2024
Segment Information	Segment information for the three and nine months ended September 29, 2024, and October 1, 2023, is as follows: Semiconductor System Robotics Wireless Segment Total Corporate Consolidated (in thousands) Three Months Ended September 29, 2024 Revenues $ 542,734 $ 73,312 $ 88,651 $ 32,601 $ 737,298 $ — $ 737,298 Income (loss) before income taxes (1)(2) 163,778 12,522 ( 24,206 ) 4,279 $ 156,373 2,611 $ 158,984 Total assets (3) 1,308,031 178,291 794,277 76,882 $ 2,357,481 1,412,247 $ 3,769,728 Three Months Ended October 1, 2023 Revenues $ 497,863 $ 83,203 $ 85,692 $ 36,974 $ 703,732 $ — $ 703,732 Income (loss) before income taxes (1)(2) 136,451 23,754 ( 21,812 ) 9,469 $ 147,862 ( 3,582 ) $ 144,280 Total assets (3) 1,382,444 178,904 684,207 92,514 $ 2,338,069 1,032,586 $ 3,370,655 Nine Months Ended September 29, 2024 Revenues $ 1,497,552 $ 209,435 $ 266,552 $ 93,457 $ 2,066,996 $ — $ 2,066,996 Income (loss) before income taxes (1)(2) 401,475 36,138 ( 56,099 ) 13,355 $ 394,869 56,420 $ 451,289 Total assets (3) 1,308,031 178,291 794,277 76,882 $ 2,357,481 1,412,247 $ 3,769,728 Nine Months Ended October 1, 2023 Revenues $ 1,387,580 $ 252,106 $ 246,541 $ 119,472 $ 2,005,699 $ — $ 2,005,699 Income (loss) before income taxes (1)(2) 361,676 67,629 ( 66,704 ) 30,841 $ 393,442 ( 7,675 ) $ 385,767 Total assets (3) 1,382,444 178,904 684,207 92,514 $ 2,338,069 1,032,586 $ 3,370,655 (1) Included in Corporate and Eliminations are interest income, interest expense, net foreign exchange gains (losses), intercompany eliminations, severance charges, pension, acquisition and divestiture related fees, and an expense for the modification of outstanding equity awards. (2) Included in income (loss) before taxes are charges related to restructuring and other, expense for the modification of outstanding equity awards, legal settlement, pension mark-to-market, and inventory charges. (3) Total assets are attributable to each segment. Corporate assets consist of cash and cash equivalents, marketable securities, and certain other assets.
Schedule of Segment Reporting Information by Segment Charges	Included in each segment are charges and credits in the following line items in the statements of operations: For the Three Months For the Nine Months September 29, October 1, September 29, October 1, (in thousands) (in thousands) Semiconductor Test: Cost of revenues—inventory charge $ 4,041 $ 10,422 $ 11,405 $ 18,374 Restructuring and other—employee severance — 1,776 1,277 5,055 System Test: Cost of revenues—inventory charge $ — $ — $ 1,016 $ 1,412 Restructuring and other—employee severance — — — 1,124 Robotics: Cost of revenues—legal settlement $ 3,600 $ — $ 3,600 $ — Restructuring and other—employee severance 1,110 636 2,647 2,707 Cost of revenues—inventory charge 537 652 1,071 2,203 Wireless: Cost of revenues—inventory charge $ 1,204 $ — $ 2,024 $ 1,080 Corporate and Eliminations: Restructuring and other—acquisition & divestiture related expenses $ — $ — $ 2,214 $ — Selling and administrative —equity modification — — 1,469 5,889 Restructuring and other—employee severance — 1,753 — 2,877 Restructuring and other—contract termination — 1,511 — 1,511 Restructuring and other—other 2,437 — 2,437 1,100

Revenue - Additional Informatio

Revenue - Additional Information (Detail) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 29, 2024	Oct. 01, 2023	Sep. 29, 2024	Oct. 01, 2023
Trade Accounts Receivable	$ 36.1	$ 94.1	$ 116.8	$ 191.2
Deferred Revenue And Customer Advances	13.4	$ 21.9	60.2	$ 91.3
Revenue, Remaining Performance Obligation, Amount	$ 1,045.4		$ 1,045.4
Short-term Contract with Customer [Member]
Revenue, Remaining Performance Obligation, Percentage	93%		93%
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction Period			12 months
Long-term Contract with Customer [Member] | Maximum [Member]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction Period			3 years
Long-term Contract with Customer [Member] | Minimum [Member]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction Period			1 year

Disaggregated Revenue by Primar

Disaggregated Revenue by Primary Geographical Market, Major Product Line and Timing of Revenue Recognition (Detail) - USD ($) $ in Thousands	3 Months Ended				9 Months Ended
	Sep. 29, 2024	[1]	Oct. 01, 2023		Sep. 29, 2024	[2]	Oct. 01, 2023
Disaggregation of Revenue [Line Items]
Total	$ 737,298		$ 703,732	[1]	$ 2,066,996		$ 2,005,699	[2]
System Test
Disaggregation of Revenue [Line Items]
Total	73,312		83,203	[1]	209,435		252,106	[2]
Wireless Test
Disaggregation of Revenue [Line Items]
Total	32,601		36,974	[1]	93,457		119,472	[2]
Point in Time
Disaggregation of Revenue [Line Items]
Total	638,836		599,099	[1]	1,764,241		1,692,038	[2]
Point in Time | System Test
Disaggregation of Revenue [Line Items]
Total	55,611		66,418	[1]	157,203		200,076	[2]
Point in Time | Wireless Test
Disaggregation of Revenue [Line Items]
Total	29,465		32,638	[1]	82,652		108,262	[2]
Over Time
Disaggregation of Revenue [Line Items]
Total	98,462		104,633	[1]	302,755		313,661	[2]
Over Time | System Test
Disaggregation of Revenue [Line Items]
Total	17,701		16,785	[1]	52,232		52,030	[2]
Over Time | Wireless Test
Disaggregation of Revenue [Line Items]
Total	3,136		4,336	[1]	10,805		11,210	[2]
Asia Pacific
Disaggregation of Revenue [Line Items]
Total	569,818		535,528	[1]	1,570,375		1,459,514	[2]
Asia Pacific | System Test
Disaggregation of Revenue [Line Items]
Total	29,277		40,464	[1]	76,317		121,698	[2]
Asia Pacific | Wireless Test
Disaggregation of Revenue [Line Items]
Total	24,342		24,727	[1]	70,776		70,320	[2]
Americas
Disaggregation of Revenue [Line Items]
Total	104,684		105,362	[2]	305,395		349,001	[1]
Americas | System Test
Disaggregation of Revenue [Line Items]
Total	39,919		35,888	[2]	105,197		105,031	[1]
Americas | Wireless Test
Disaggregation of Revenue [Line Items]
Total	5,515		10,139	[2]	16,240		42,476	[1]
Europe, Middle East and Africa
Disaggregation of Revenue [Line Items]
Total	62,796		62,842	[1]	191,226		197,184	[2]
Europe, Middle East and Africa | System Test
Disaggregation of Revenue [Line Items]
Total	4,116		6,851	[1]	27,921		25,377	[2]
Europe, Middle East and Africa | Wireless Test
Disaggregation of Revenue [Line Items]
Total	2,744		2,108	[1]	6,441		6,676	[2]
SOC | Semiconductor Test
Disaggregation of Revenue [Line Items]
Total	392,355		404,110	[1]	1,108,247		1,105,638	[2]
SOC | Point in Time | Semiconductor Test
Disaggregation of Revenue [Line Items]
Total	323,507		330,846	[1]	896,635		886,201	[2]
SOC | Over Time | Semiconductor Test
Disaggregation of Revenue [Line Items]
Total	68,848		73,264	[1]	211,612		219,436	[2]
SOC | Asia Pacific | Semiconductor Test
Disaggregation of Revenue [Line Items]
Total	364,476		360,375	[1]	1,016,674		946,696	[2]
SOC | Americas | Semiconductor Test
Disaggregation of Revenue [Line Items]
Total	17,150		24,752	[2]	59,912		98,511	[1]
SOC | Europe, Middle East and Africa | Semiconductor Test
Disaggregation of Revenue [Line Items]
Total	10,729		18,983	[1]	31,661		60,431	[2]
Memory | Semiconductor Test
Disaggregation of Revenue [Line Items]
Total	150,379		93,753	[1]	389,305		281,942	[2]
Memory | Point in Time | Semiconductor Test
Disaggregation of Revenue [Line Items]
Total	143,581		86,247	[1]	367,679		260,052	[2]
Memory | Over Time | Semiconductor Test
Disaggregation of Revenue [Line Items]
Total	6,798		7,506	[1]	21,626		21,890	[2]
Memory | Asia Pacific | Semiconductor Test
Disaggregation of Revenue [Line Items]
Total	137,890		91,352	[1]	357,993		270,297	[2]
Memory | Americas | Semiconductor Test
Disaggregation of Revenue [Line Items]
Total	1,325		1,356	[2]	13,631		8,586	[1]
Memory | Europe, Middle East and Africa | Semiconductor Test
Disaggregation of Revenue [Line Items]
Total	11,164		1,045	[1]	17,681		3,059	[2]
Universal Robots (UR) | Robotics
Disaggregation of Revenue [Line Items]
Total	73,418		70,545	[1]	215,764		200,429	[2]
Universal Robots (UR) | Point in Time | Robotics
Disaggregation of Revenue [Line Items]
Total	71,607		68,938	[1]	210,222		194,698	[2]
Universal Robots (UR) | Over Time | Robotics
Disaggregation of Revenue [Line Items]
Total	1,811		1,607	[1]	5,542		5,731	[2]
Universal Robots (UR) | Asia Pacific | Robotics
Disaggregation of Revenue [Line Items]
Total	10,873		15,430	[1]	37,254		43,530	[2]
Universal Robots (UR) | Americas | Robotics
Disaggregation of Revenue [Line Items]
Total	32,315		26,073	[2]	82,220		69,346	[1]
Universal Robots (UR) | Europe, Middle East and Africa | Robotics
Disaggregation of Revenue [Line Items]
Total	30,230		29,042	[1]	96,290		87,553	[2]
MiR | Robotics
Disaggregation of Revenue [Line Items]
Total	15,233		15,147	[1]	50,788		46,112	[2]
MiR | Point in Time | Robotics
Disaggregation of Revenue [Line Items]
Total	15,065		14,012	[1]	49,850		42,748	[2]
MiR | Over Time | Robotics
Disaggregation of Revenue [Line Items]
Total	168		1,135	[1]	938		3,364	[2]
MiR | Asia Pacific | Robotics
Disaggregation of Revenue [Line Items]
Total	2,960		3,180	[1]	11,361		6,973	[2]
MiR | Americas | Robotics
Disaggregation of Revenue [Line Items]
Total	8,460		7,154	[2]	28,195		25,051	[1]
MiR | Europe, Middle East and Africa | Robotics
Disaggregation of Revenue [Line Items]
Total	$ 3,813		$ 4,813	[1]	$ 11,232		$ 14,088	[2]
[1] Include s $ 0.8 million and $ 1.4 million in 2024, and 2023, respectively, for leases of Teradyne’s systems recognized outside Accounting Standards Codification (“ASC”) 606 “Revenue from Contracts with Customers.” Includes $ 2.5 million and $ 3.9 million in 2024 and 2023, respectively, for leases of Teradyne’s systems recognized outside Accounting Standards Codification (“ASC”) 606 “Revenue from Contracts with Customers.”

Disaggregated Revenue by Prim_2

Disaggregated Revenue by Primary Geographical Market, Major Product Line and Timing of Revenue Recognition (Parenthetical) (Detail) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 29, 2024	Oct. 01, 2023	Sep. 29, 2024	Oct. 01, 2023
Accounting Policies [Abstract]
Revenue on leases	$ 0.8	$ 1.4	$ 2.5	$ 3.9

Deferred Revenue and Customer A

Deferred Revenue and Customer Advances (Detail) - USD ($) $ in Thousands	Sep. 29, 2024	Jun. 30, 2024	Dec. 31, 2023	Oct. 01, 2023	Jul. 02, 2023	Dec. 31, 2022
Deferred Revenue Arrangement [Line Items]
Maintenance, service and training	$ 57,866		$ 66,458
Customer advances, undelivered elements and other	44,116		35,731
Extended warranty	38,929	$ 33,512	34,897	$ 38,843	$ 44,422	$ 56,180
Total deferred revenue and customer advances	$ 140,911		$ 137,086

Dispositions - Additional Infor

Dispositions - Additional Information (Detail) - USD ($) $ in Thousands		3 Months Ended		9 Months Ended
	May 27, 2024	Sep. 29, 2024	Oct. 01, 2023	Sep. 29, 2024	Oct. 01, 2023
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Pre-tax gain on sale of business		$ 0	$ 0	$ 57,486	$ 0
Device Interface Solutions
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Proceeds from sale of business	$ 85,000
Pre-tax gain on sale of business				$ 57,500

Schedule of Assets and Liabilit

Schedule of Assets and Liabilities Related to the DIS Sale Agreement (Detail) - USD ($) $ in Thousands	Sep. 29, 2024	Dec. 31, 2023
Current assets:
Prepayments		$ 5,300
Total current assets held for sale	$ 0	23,250
Total assets held for sale	0	11,531
Current liabilities:
Total current liabilities held for sale	0	7,379
Total liabilities held for sale	$ 0	2,000
Device Interface Solutions
Current assets:
Inventories, net		17,952
Prepayments		5,298
Total current assets held for sale		23,250
Property, plant and equipment, net		8,986
Operating lease right-of-use assets, net		2,545
Total assets held for sale		34,781
Current liabilities:
Accounts payable		6,356
Other accrued liabilities		552
Operating lease liabilities		471
Total current liabilities held for sale		7,379
Long-term operating lease liabilities		2,000
Total liabilities held for sale		9,379
Net assets held for sale		$ 25,402

Equity Method Investments - Add

Equity Method Investments - Additional Information (Detail) - USD ($)		9 Months Ended
	May 27, 2024	Sep. 29, 2024	Sep. 30, 2024	Jun. 30, 2024	Dec. 31, 2023
Equity Method Investments and Joint Ventures [Abstract]
Payment to purchase issued and outstanding shares by Technoprobe	$ 524,100,000
Equity method investment		$ 538,351,000		$ 524,060,000	$ 0
Percentage of issued and outstanding shares acquired	10%
Fair value of publicly-traded investment in Technoprobe		471,800,000
Equity method investment, other-than-temporary impairment		$ 0
Aggregate cost			$ 204,700,000

Equity Method Investment - Summ

Equity Method Investment - Summary of Equity Method Investment (Detail) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
	Sep. 29, 2024	Sep. 29, 2024
Equity Method Investments and Joint Ventures [Abstract]
Balance at June 30, 2024	$ 524,060	$ 0
Other comprehensive income related to investment	15,366
Equity in net earnings of affiliate	(1,075)	(1,075)
Balance at September 29, 2024	$ 538,351	$ 538,351

Composition of Inventories, Net

Composition of Inventories, Net (Detail) - USD ($) $ in Thousands		Sep. 29, 2024	Dec. 31, 2023
Inventory Disclosure [Abstract]
Raw material		$ 216,019	$ 258,422
Work-in-process		48,249	26,851
Finished goods		33,072	24,701
Total inventories, net	[1]	$ 297,340	$ 309,974
[1] Inventories, net at December 31, 2023, exclude $ 18.0 million of primarily work-in-process inventories, net classified as assets held for sale. See Note E: "Dispositions" for additional information.

Composition of Inventories, N_2

Composition of Inventories, Net (Parenthetical) (Detail) $ in Millions	Dec. 31, 2023 USD ($)
Inventory Disclosure [Abstract]
Inventory work in process held for sale	$ 18

Inventories - Additional Inform

Inventories - Additional Information (Detail) - USD ($) $ in Millions	Sep. 29, 2024	Dec. 31, 2023
Inventory [Line Items]
Inventory reserves	$ 140.5	$ 136

Financial Instruments - Additio

Financial Instruments - Additional Information (Detail) € in Millions			3 Months Ended		9 Months Ended		12 Months Ended
	Apr. 12, 2024 EUR (€)	Nov. 07, 2023 EUR (€)	Sep. 29, 2024 USD ($)	Oct. 01, 2023 USD ($)	Sep. 29, 2024 USD ($)	Oct. 01, 2023 USD ($)	Dec. 31, 2023 USD ($)
Financial Instruments and Fair Value [Line Items]
Available-for-sale securities, realized gain			$ 800,000	$ 100,000	$ 2,100,000	$ 600,000
Available-for-sale securities, realized loss			0	0	300,000	300,000
Fair market value of investments with unrealized losses greater than one year			44,100,000		44,100,000		$ 65,200,000
Fair market value of investments with unrealized losses less than one year			8,300,000		8,300,000		22,300,000
Unrealized loss on contracts, net			(2,900,000)	5,300,000	3,100,000	12,300,000
Equity securities unrealized gain			2,200,000	0	5,400,000	4,600,000
Equity securities unrealized loss			0	1,700,000	0	1,700,000
Other comprehensive income (Loss), cash flow hedge, gain (loss), before reclassification, after tax			(260,000)	$ 2,590,000	1,014,000	$ 6,456,000
Call Option
Financial Instruments and Fair Value [Line Items]
Realized loss on contracts, net					(9,800,000)
Expiration date of the option		Apr. 26, 2024
Fair value of outstanding contracts							17,400,000
Technoprobe S.p.A
Financial Instruments and Fair Value [Line Items]
Percentage of investment acquired		10%
Technoprobe S.p.A | Call Option
Financial Instruments and Fair Value [Line Items]
Notional Amount | €		€ 481
Cash Flow Hedging [Member]
Financial Instruments and Fair Value [Line Items]
Other comprehensive income (Loss), cash flow hedge, gain (loss), before reclassification, after tax					(300,000)		600,000
Debt Mutual Funds
Financial Instruments and Fair Value [Line Items]
Available for sale securities with out contractual maturity date			$ 8,600,000		8,600,000
Forward
Financial Instruments and Fair Value [Line Items]
Notional Amount | €	€ 481
Expiration date of the option	May 23, 2024
Foreign Exchange Contracts
Financial Instruments and Fair Value [Line Items]
Unrealized loss on contracts, net					$ (800,000)		$ (1,800,000)

Schedule of Fair Value of Finan

Schedule of Fair Value of Financial Assets and Liabilities Measured on Recurring Basis (Detail) - USD ($) $ in Thousands	Sep. 29, 2024	Dec. 31, 2023
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Available for sale securities	$ 114,095	$ 132,456
U.S. Treasury Securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Available for sale securities	41,833	41,808
Corporate Debt Securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Available for sale securities	37,149	52,734
Certificates of Deposit and Time Deposits
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Available for sale securities	21,741	21,772
Debt Mutual Funds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Available for sale securities	8,640	8,773
U.S. Government Agency Securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Available for sale securities	3,931	4,892
Commercial Paper
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Available for sale securities		1,667
Non-U.S. Government Securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Available for sale securities	801	810
Fair Value, Measurements, Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Total	677,611	937,159
Derivative assets	332	18,746
Total	677,943	955,905
Derivative liabilities	1,435	2,545
Total	1,435	2,545
Fair Value, Measurements, Recurring | Cash
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Cash and cash equivalents	198,946	298,156
Fair Value, Measurements, Recurring | Cash Equivalents
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Cash and cash equivalents	311,090	459,415
Fair Value, Measurements, Recurring | U.S. Treasury Securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Available for sale securities	41,833	41,808
Fair Value, Measurements, Recurring | Corporate Debt Securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Available for sale securities	37,149	52,734
Fair Value, Measurements, Recurring | Certificates of Deposit and Time Deposits
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Available for sale securities	21,741	21,772
Fair Value, Measurements, Recurring | Debt Mutual Funds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Available for sale securities	8,640	8,773
Fair Value, Measurements, Recurring | U.S. Government Agency Securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Available for sale securities	3,931	4,892
Fair Value, Measurements, Recurring | Commercial Paper
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Available for sale securities		1,667
Fair Value, Measurements, Recurring | Non-U.S. Government Securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Available for sale securities	801	810
Fair Value, Measurements, Recurring | Mutual Funds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Available for sale equity securities	53,480	47,132
Quoted Prices in Active Markets for Identical Instruments (Level 1) | Fair Value, Measurements, Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Total	569,066	807,359
Derivative assets	0	0
Total	569,066	807,359
Derivative liabilities	0	0
Total	0	0
Quoted Prices in Active Markets for Identical Instruments (Level 1) | Fair Value, Measurements, Recurring | Cash
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Cash and cash equivalents	198,946	298,156
Quoted Prices in Active Markets for Identical Instruments (Level 1) | Fair Value, Measurements, Recurring | Cash Equivalents
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Cash and cash equivalents	308,000	453,298
Quoted Prices in Active Markets for Identical Instruments (Level 1) | Fair Value, Measurements, Recurring | U.S. Treasury Securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Available for sale securities		0
Quoted Prices in Active Markets for Identical Instruments (Level 1) | Fair Value, Measurements, Recurring | Corporate Debt Securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Available for sale securities		0
Quoted Prices in Active Markets for Identical Instruments (Level 1) | Fair Value, Measurements, Recurring | Certificates of Deposit and Time Deposits
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Available for sale securities		0
Quoted Prices in Active Markets for Identical Instruments (Level 1) | Fair Value, Measurements, Recurring | Debt Mutual Funds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Available for sale securities	8,640	8,773
Quoted Prices in Active Markets for Identical Instruments (Level 1) | Fair Value, Measurements, Recurring | U.S. Government Agency Securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Available for sale securities		0
Quoted Prices in Active Markets for Identical Instruments (Level 1) | Fair Value, Measurements, Recurring | Commercial Paper
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Available for sale securities		0
Quoted Prices in Active Markets for Identical Instruments (Level 1) | Fair Value, Measurements, Recurring | Non-U.S. Government Securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Available for sale securities		0
Quoted Prices in Active Markets for Identical Instruments (Level 1) | Fair Value, Measurements, Recurring | Mutual Funds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Available for sale equity securities	53,480	47,132
Significant Other Observable Inputs (Level 2) | Fair Value, Measurements, Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Total	108,545	129,800
Derivative assets	332	18,746
Total	108,877	148,546
Derivative liabilities	1,435	2,545
Total	1,435	2,545
Significant Other Observable Inputs (Level 2) | Fair Value, Measurements, Recurring | Cash
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Cash and cash equivalents	0	0
Significant Other Observable Inputs (Level 2) | Fair Value, Measurements, Recurring | Cash Equivalents
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Cash and cash equivalents	3,090	6,117
Significant Other Observable Inputs (Level 2) | Fair Value, Measurements, Recurring | U.S. Treasury Securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Available for sale securities	41,833	41,808
Significant Other Observable Inputs (Level 2) | Fair Value, Measurements, Recurring | Corporate Debt Securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Available for sale securities	37,149	52,734
Significant Other Observable Inputs (Level 2) | Fair Value, Measurements, Recurring | Certificates of Deposit and Time Deposits
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Available for sale securities	21,741	21,772
Significant Other Observable Inputs (Level 2) | Fair Value, Measurements, Recurring | Debt Mutual Funds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Available for sale securities		0
Significant Other Observable Inputs (Level 2) | Fair Value, Measurements, Recurring | U.S. Government Agency Securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Available for sale securities	3,931	4,892
Significant Other Observable Inputs (Level 2) | Fair Value, Measurements, Recurring | Commercial Paper
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Available for sale securities		1,667
Significant Other Observable Inputs (Level 2) | Fair Value, Measurements, Recurring | Non-U.S. Government Securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Available for sale securities	801	810
Significant Other Observable Inputs (Level 2) | Fair Value, Measurements, Recurring | Mutual Funds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Available for sale equity securities		0
Significant Unobservable Inputs (Level 3) | Fair Value, Measurements, Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Total		0
Derivative assets	0	0
Total	0	0
Derivative liabilities	0	0
Total	0	0
Significant Unobservable Inputs (Level 3) | Fair Value, Measurements, Recurring | Cash
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Cash and cash equivalents	0	0
Significant Unobservable Inputs (Level 3) | Fair Value, Measurements, Recurring | Cash Equivalents
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Cash and cash equivalents	0	0
Significant Unobservable Inputs (Level 3) | Fair Value, Measurements, Recurring | U.S. Treasury Securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Available for sale securities		0
Significant Unobservable Inputs (Level 3) | Fair Value, Measurements, Recurring | Corporate Debt Securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Available for sale securities		0
Significant Unobservable Inputs (Level 3) | Fair Value, Measurements, Recurring | Certificates of Deposit and Time Deposits
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Available for sale securities		0
Significant Unobservable Inputs (Level 3) | Fair Value, Measurements, Recurring | Debt Mutual Funds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Available for sale securities		0
Significant Unobservable Inputs (Level 3) | Fair Value, Measurements, Recurring | U.S. Government Agency Securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Available for sale securities		0
Significant Unobservable Inputs (Level 3) | Fair Value, Measurements, Recurring | Commercial Paper
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Available for sale securities		0
Significant Unobservable Inputs (Level 3) | Fair Value, Measurements, Recurring | Non-U.S. Government Securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Available for sale securities		0
Significant Unobservable Inputs (Level 3) | Fair Value, Measurements, Recurring | Mutual Funds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Available for sale equity securities		$ 0

Schedule of Reported Financial

Schedule of Reported Financial Assets and Liabilities (Detail) - Fair Value, Measurements, Recurring - USD ($) $ in Thousands	Sep. 29, 2024	Dec. 31, 2023
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Assets	$ 677,943	$ 955,905
Liabilities	1,435	2,545
Other Current Liabilities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Liabilities	1,435	2,545
Other Current Assets
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Assets	332	18,746
Cash and Cash Equivalents
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Assets	510,036	757,571
Marketable securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Assets	41,631	62,154
Long-term marketable securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Assets	125,944	117,434
Quoted Prices in Active Markets for Identical Instruments (Level 1)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Assets	569,066	807,359
Liabilities	0	0
Quoted Prices in Active Markets for Identical Instruments (Level 1) | Other Current Liabilities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Liabilities	0	0
Quoted Prices in Active Markets for Identical Instruments (Level 1) | Other Current Assets
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Assets	0	0
Quoted Prices in Active Markets for Identical Instruments (Level 1) | Cash and Cash Equivalents
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Assets	506,946	751,454
Quoted Prices in Active Markets for Identical Instruments (Level 1) | Marketable securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Assets	0	0
Quoted Prices in Active Markets for Identical Instruments (Level 1) | Long-term marketable securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Assets	62,120	55,905
Significant Other Observable Inputs (Level 2)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Assets	108,877	148,546
Liabilities	1,435	2,545
Significant Other Observable Inputs (Level 2) | Other Current Liabilities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Liabilities	1,435	2,545
Significant Other Observable Inputs (Level 2) | Other Current Assets
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Assets	332	18,746
Significant Other Observable Inputs (Level 2) | Cash and Cash Equivalents
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Assets	3,090	6,117
Significant Other Observable Inputs (Level 2) | Marketable securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Assets	41,631	62,154
Significant Other Observable Inputs (Level 2) | Long-term marketable securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Assets	63,824	61,529
Significant Unobservable Inputs (Level 3)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Assets	0	0
Liabilities	0	0
Significant Unobservable Inputs (Level 3) | Other Current Liabilities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Liabilities	0	0
Significant Unobservable Inputs (Level 3) | Other Current Assets
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Assets	0	0
Significant Unobservable Inputs (Level 3) | Cash and Cash Equivalents
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Assets	0	0
Significant Unobservable Inputs (Level 3) | Marketable securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Assets	0	0
Significant Unobservable Inputs (Level 3) | Long-term marketable securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Assets	$ 0	$ 0

Schedule of Carrying Amounts an

Schedule of Carrying Amounts and Fair Values of Financial Instruments (Detail) - USD ($) $ in Thousands	Sep. 29, 2024	Dec. 31, 2023
Fair Value, Balance Sheet Grouping, Financial Statement Captions
Available-for-sale marketable securities, Fair Market Value	$ 114,095	$ 132,456
Carrying Value
Fair Value, Balance Sheet Grouping, Financial Statement Captions
Cash and cash equivalents	510,036	757,571
Available-for-sale marketable securities, Fair Market Value	167,575	179,588
Derivative assets	332	18,746
Derivative liabilities	$ 1,435	$ 2,545
Derivative Liability, Statement of Financial Position [Extensible Enumeration]	Deferred Tax and Other Liabilities, Noncurrent	Deferred Tax and Other Liabilities, Noncurrent
Derivative Asset, Statement of Financial Position [Extensible Enumeration]	Other Assets, Noncurrent	Other Assets, Noncurrent
Fair Value
Fair Value, Balance Sheet Grouping, Financial Statement Captions
Cash and cash equivalents	$ 510,036	$ 757,571
Available-for-sale marketable securities, Fair Market Value	167,575	179,588
Derivative assets	332	18,746
Derivative liabilities	$ 1,435	$ 2,545
Derivative Liability, Statement of Financial Position [Extensible Enumeration]	Deferred Tax and Other Liabilities, Noncurrent	Deferred Tax and Other Liabilities, Noncurrent
Derivative Asset, Statement of Financial Position [Extensible Enumeration]	Other Assets, Noncurrent	Other Assets, Noncurrent

Schedule of Available for Sale

Schedule of Available for Sale Marketable Securities (Detail) - USD ($) $ in Thousands	Sep. 29, 2024	Dec. 31, 2023
Schedule of Available-for-sale Securities
Available-for-sale marketable securities, Cost	$ 120,817	$ 140,377
Available-for-sale marketable securities, Unrealized Gain	440	249
Available-for-sale marketable securities, Unrealized (Loss)	(7,162)	(8,170)
Available-for-sale marketable securities, Fair Market Value	114,095	132,456
Available-for-sale marketable securities, Fair Market Value of Investments with Unrealized Losses	52,428	87,538
U.S. Treasury Securities
Schedule of Available-for-sale Securities
Available-for-sale marketable securities, Cost	45,522	45,725
Available-for-sale marketable securities, Unrealized Gain	106	14
Available-for-sale marketable securities, Unrealized (Loss)	(3,795)	(3,931)
Available-for-sale marketable securities, Fair Market Value	41,833	41,808
Available-for-sale marketable securities, Fair Market Value of Investments with Unrealized Losses	22,985	35,080
Corporate Debt Securities
Schedule of Available-for-sale Securities
Available-for-sale marketable securities, Cost	39,986	56,458
Available-for-sale marketable securities, Unrealized Gain	323	201
Available-for-sale marketable securities, Unrealized (Loss)	(3,160)	(3,925)
Available-for-sale marketable securities, Fair Market Value	37,149	52,734
Available-for-sale marketable securities, Fair Market Value of Investments with Unrealized Losses	25,248	44,263
Certificates of Deposit and Time Deposits
Schedule of Available-for-sale Securities
Available-for-sale marketable securities, Cost	21,741	21,772
Available-for-sale marketable securities, Unrealized Gain		0
Available-for-sale marketable securities, Unrealized (Loss)		0
Available-for-sale marketable securities, Fair Market Value	21,741	21,772
Available-for-sale marketable securities, Fair Market Value of Investments with Unrealized Losses		0
Debt Mutual Funds
Schedule of Available-for-sale Securities
Available-for-sale marketable securities, Cost	8,846	9,081
Available-for-sale marketable securities, Unrealized Gain		0
Available-for-sale marketable securities, Unrealized (Loss)	(206)	(308)
Available-for-sale marketable securities, Fair Market Value	8,640	8,773
Available-for-sale marketable securities, Fair Market Value of Investments with Unrealized Losses	3,319	3,303
U.S. Government Agency Securities
Schedule of Available-for-sale Securities
Available-for-sale marketable securities, Cost	3,921	4,898
Available-for-sale marketable securities, Unrealized Gain	11	0
Available-for-sale marketable securities, Unrealized (Loss)	(1)	(6)
Available-for-sale marketable securities, Fair Market Value	3,931	4,892
Available-for-sale marketable securities, Fair Market Value of Investments with Unrealized Losses	876	4,892
Commercial Paper
Schedule of Available-for-sale Securities
Available-for-sale marketable securities, Cost		1,633
Available-for-sale marketable securities, Unrealized Gain		34
Available-for-sale marketable securities, Unrealized (Loss)		0
Available-for-sale marketable securities, Fair Market Value		1,667
Available-for-sale marketable securities, Fair Market Value of Investments with Unrealized Losses		0
Non-U.S. Government Securities
Schedule of Available-for-sale Securities
Available-for-sale marketable securities, Cost	801	810
Available-for-sale marketable securities, Unrealized Gain		0
Available-for-sale marketable securities, Unrealized (Loss)		0
Available-for-sale marketable securities, Fair Market Value	801	810
Available-for-sale marketable securities, Fair Market Value of Investments with Unrealized Losses		$ 0

Schedule of Reported Available

Schedule of Reported Available for Sale Marketable Securities (Detail) - USD ($) $ in Thousands	Sep. 29, 2024	Dec. 31, 2023
Schedule of Available-for-sale Securities
Available-for-sale marketable securities, Cost	$ 120,817	$ 140,377
Available-for-sale marketable securities, Unrealized Gain	440	249
Available-for-sale marketable securities, Unrealized (Loss)	(7,162)	(8,170)
Available-for-sale marketable securities, Fair Market Value	114,095	132,456
Available-for-sale marketable securities, Fair Market Value of Investments with Unrealized Losses	52,428	87,538
Marketable securities
Schedule of Available-for-sale Securities
Available-for-sale marketable securities, Cost	41,673	62,385
Available-for-sale marketable securities, Unrealized Gain	20	36
Available-for-sale marketable securities, Unrealized (Loss)	(62)	(267)
Available-for-sale marketable securities, Fair Market Value	41,631	62,154
Available-for-sale marketable securities, Fair Market Value of Investments with Unrealized Losses	9,973	34,844
Long-term marketable securities
Schedule of Available-for-sale Securities
Available-for-sale marketable securities, Cost	79,144	77,992
Available-for-sale marketable securities, Unrealized Gain	420	213
Available-for-sale marketable securities, Unrealized (Loss)	(7,100)	(7,903)
Available-for-sale marketable securities, Fair Market Value	72,464	70,302
Available-for-sale marketable securities, Fair Market Value of Investments with Unrealized Losses	$ 42,455	$ 52,694

Contractual Maturities of Inves

Contractual Maturities of Investments in Debt Securities Held (Detail) $ in Thousands	Sep. 29, 2024 USD ($)
Schedule of Available-for-sale Securities
Due within one year, cost	$ 41,673
Due after 1 year through 5 years, cost	25,690
Due after 5 years through 10 years, cost	7,950
Due after 10 years, cost	36,658
Total, cost	111,971
Due within one year, fair market value	41,631
Due after 1 year through 5 years, fair market value	25,729
Due after 5 years through 10 years, fair market value	7,908
Due after 10 years, fair maket value	30,187
Total, fair market value	$ 105,455

Schedule of Notional Amount of

Schedule of Notional Amount of Derivatives (Detail) - USD ($) $ in Millions	Sep. 29, 2024	Dec. 31, 2023
Intercompany Foreign Currency Balance [Line Items]
Derivative Liability, Notional amounts	$ 146.1
Derivative Asset, Notional amounts		$ 152.1
U.S. dollar/Taiwan dollar
Intercompany Foreign Currency Balance [Line Items]
Derivative Liability, Notional amounts	29.6	42.7
U.S. dollar/Japanese yen
Intercompany Foreign Currency Balance [Line Items]
Derivative Liability, Notional amounts	21.7	11
U.S. dollar/Korean won
Intercompany Foreign Currency Balance [Line Items]
Derivative Liability, Notional amounts	8.9	7.2
U.S. dollar/British pound sterling
Intercompany Foreign Currency Balance [Line Items]
Derivative Liability, Notional amounts	1	1.5
Danish krone/U.S. dollar
Intercompany Foreign Currency Balance [Line Items]
Derivative Liability, Notional amounts	0	36
Derivative Asset, Notional amounts	25.7	0.7
Euro/U.S. dollar
Intercompany Foreign Currency Balance [Line Items]
Derivative Asset, Notional amounts	24.8	25.3
Singapore dollar/U.S. dollar
Intercompany Foreign Currency Balance [Line Items]
Derivative Asset, Notional amounts	23	16.6
Philippine peso/U.S. dollar
Intercompany Foreign Currency Balance [Line Items]
Derivative Asset, Notional amounts	9.7	10.1
Chinese yuan/U.S. dollar
Intercompany Foreign Currency Balance [Line Items]
Derivative Asset, Notional amounts	$ 1.7	$ 1

Schedule Of Foreign Currency Ca

Schedule Of Foreign Currency Cash Flow Hedges (Detail) - Foreign Exchange Forward [Member] - Cash Flow Hedging [Member] - USD ($) $ in Millions	Sep. 29, 2024	Dec. 31, 2023
Derivative, Notional Amount	$ 12.1	$ 35.5
Long [Member] | U.S. dollar/Japanese yen
Derivative, Notional Amount	$ 12.1	$ 35.5

Schedule of Derivative Instrume

Schedule of Derivative Instruments in Statement of Financial Position at Fair Value (Detail) - USD ($) $ in Thousands	Sep. 29, 2024	Dec. 31, 2023
Derivatives, Fair Value [Line Items]
Derivative assets (liabilities), net	$ (1,103)	$ 16,200
Not Designated as Hedging Instrument | Foreign Exchange Forward [Member] | Other Current Assets
Derivatives, Fair Value [Line Items]
Derivative assets	332	733
Not Designated as Hedging Instrument | Foreign Exchange Forward [Member] | Other Current Liabilities
Derivatives, Fair Value [Line Items]
Derivative liabilities	(1,102)	(2,545)
Not Designated as Hedging Instrument | Foreign Exchange Option [Member] | Other Current Assets
Derivatives, Fair Value [Line Items]
Derivative assets	0	17,364
Designated as Hedging Instrument [Member] | Foreign Exchange Forward [Member] | Other Current Assets
Derivatives, Fair Value [Line Items]
Derivative assets	0	648
Designated as Hedging Instrument [Member] | Foreign Exchange Forward [Member] | Other Current Liabilities
Derivatives, Fair Value [Line Items]
Derivative liabilities	$ (333)	$ 0

Schedule of Effect of Derivativ

Schedule of Effect of Derivative Instruments in Statement of Operations Recognized (Detail) - USD ($) $ in Thousands		3 Months Ended		9 Months Ended
		Sep. 29, 2024	Oct. 01, 2023	Sep. 29, 2024	Oct. 01, 2023
Foreign Exchange Option [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gain (Loss) on Foreign Currency Derivatives Recorded in Earnings, Net		$ 4,829	$ (5,846)	$ 8,170	$ (6,675)
Other (income) expense, net | Not Designated as Hedging Instrument [Member] | Foreign Exchange Forward [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Losses (Gains) on derivatives recognized in statements of operations	[1]	4,829	(1,886)	686	(4,667)
Other (income) expense, net | Not Designated as Hedging Instrument [Member] | Foreign Exchange Option [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gain (Loss) on Foreign Currency Derivatives Recorded in Earnings, Net		0	0	9,764	0
Sales [Member] | Designated as Hedging Instrument [Member] | Foreign Exchange Forward and Option Contracts [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gain (Loss) on Foreign Currency Derivatives Recorded in Earnings, Net		$ 0	$ (3,960)	$ (2,280)	$ (2,008)
[1] The table does not reflect the corresponding gains and losses from the remeasurement of the monetary assets and liabilities denominated in foreign currencies. For the three and nine months ended September 29, 2024, net losses (gains) from remeasurement of monetary assets and liabilities denominated in foreign currencies were $ ( 2.9 ) million and $ 3.1 million, respectively. For the three and nine months ended October 1, 2023, net losses from remeasurement of monetary assets and liabilities denominated in foreign currencies were $ 5.3 million and $ 12.3 million, respectively.

Schedule of Effect of Derivat_2

Schedule of Effect of Derivative Instruments in Statement of Operations Recognized (Parenthetical) (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 29, 2024	Oct. 01, 2023	Sep. 29, 2024	Oct. 01, 2023
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Unrealized Gain (loss) on contracts	$ (2.9)	$ 5.3	$ 3.1	$ 12.3

Debt - Additional Information (

Debt - Additional Information (Detail) - USD ($) $ / shares in Units, shares in Millions		3 Months Ended	9 Months Ended
	Dec. 12, 2016	Sep. 29, 2024	Sep. 29, 2024	Oct. 01, 2023	May 27, 2024	May 16, 2024	Dec. 31, 2023	Oct. 05, 2022	May 01, 2020
Debt Instrument
Repurchase of common stock			$ 55,053,000	$ 346,492,000
Stock issued during period, value		$ 1,200,000	10,000,000
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	$ 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%
Percentage of issued and outstanding shares acquired					10%
Retained Earnings (Accumulated Deficit)		$ 990,039,000	$ 990,039,000				$ 706,514,000
Warrant [Member]
Debt Instrument
Warrant expired		1.3	14.7
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%
Debt instrument, net proceeds after issuance costs	$ 450,800,000
Payment for net cost of convertible note hedges net of warrant proceeds	33,000,000
Repurchase of common stock	$ 50,100,000
Repurchase of stock, shares	2
Debt instrument, frequency of periodic payment	payable semiannually in arrears on June 15 and December 15 of each year
1.25% Convertible Senior Unsecured Notes
Debt Instrument
Senior notes maturity date	Dec. 15, 2023
Shares that would be issued upon conversion			1.3
Strike price per share of warrant			$ 39.35
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			0.75%
Revolving Credit Facility | Base Rate | Minimum | Truist Bank [Member]
Debt Instrument
Debt instrument, basis spread on variable rate			0%
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%
Credit Agreement
Debt Instrument
Borrowed amount		$ 0	$ 0			$ 185,000,000
Percentage of issued and outstanding shares acquired						10%

Interest Expense on Teradyne's

Interest Expense on Teradyne's Senior Notes (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 29, 2024	Oct. 01, 2023	Sep. 29, 2024	Oct. 01, 2023
Debt Instrument
Contractual interest expense on the coupon	$ 0	$ 74	$ 0	$ 312
Amortization of debt issuance fees recognized as interest expense	0	0	0	113
Total interest expense on the convertible debt	$ 0	$ 74	$ 0	$ 425

Schedule of Prepayments and Oth

Schedule of Prepayments and Other Current Assets (Detail) - USD ($) $ in Thousands		Sep. 29, 2024	Dec. 31, 2023
Prepaid And Other Current Assets [Line Items]
Contract manufacturer and supplier prepayments		$ 439,647	$ 502,257
Prepaid maintenance and other services		19,040	17,592
Prepaid taxes		20,734	16,083
Other prepayments		10,127	13,038
Total prepayments	[1]	$ 489,548	$ 548,970
[1] Exclude s $ 5.3 million at December 31, 2023 , of contract manufacturer and supplier prepayments, classified as assets held for sale. See Note E: “Dispositions” for additional information.

Prepayments - Schedule of Prepa

Prepayments - Schedule of Prepayments and Other Current Assets (Parenthetical) (Details) $ in Millions	Dec. 31, 2023 USD ($)
Prepayments [Abstract]
Contract manufacturer and supplier prepayments, classified as assets held for sale	$ 5.3

Warranty Accrual Included in Ot

Warranty Accrual Included in Other Accrued Liabilities (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 29, 2024	Oct. 01, 2023	Sep. 29, 2024	Oct. 01, 2023
Product Warranty Liability [Line Items]
Balance at beginning of period	$ 15,244	$ 12,543	$ 15,698	$ 14,181
Accruals for warranties issued during the period	2,149	8,859	8,331	16,237
Accruals related to pre-existing warranties	(545)	(795)	(1,513)	(1,552)
Settlements made during the period	(2,990)	(5,892)	(8,658)	(14,151)
Balance at end of period	$ 13,858	$ 14,715	$ 13,858	$ 14,715

Extended Product Warranty of Sh

Extended Product Warranty of Short and Long-Term Deferred Revenue and Customer Advances (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 29, 2024	Oct. 01, 2023	Sep. 29, 2024	Oct. 01, 2023
Product Warranty Liability [Line Items]
Balance at beginning of period	$ 33,512	$ 44,422	$ 34,897	$ 56,180
Deferral of new extended warranty revenue	9,714	2,734	22,316	11,615
Recognition of extended warranty deferred revenue	(4,297)	(8,313)	(18,284)	(28,952)
Balance at end of period	$ 38,929	$ 38,843	$ 38,929	$ 38,843

Stock-Based Compensation - Addi

Stock-Based Compensation - Additional Information (Detail) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	9 Months Ended
	Sep. 29, 2024	Oct. 01, 2023
Share-based Compensation Arrangement by Share-based Payment Award
Total shareholder return performance measurement period	3 years
Stock price	$ 95.14	$ 104.15
Description of retirement policy	On January 22, 2024, the Board enacted the Executive Retirement Policy for Restricted Stock Unit and Option Vesting (the "Retirement Policy"). Under the Retirement Policy, an executive officer that is over the age of 65 and has 10 or more years of service as of the effective date of his or her retirement will be eligible for continued vesting of his or her unvested time-based restricted stock units and stock options granted prior to his or her retirement date.
Retirement Agreement [Member]
Share-based Compensation Arrangement by Share-based Payment Award
Allocated share-based compensation expense		$ 5.9
Employee Stock Option [Member]
Share-based Compensation Arrangement by Share-based Payment Award
Percentage of common stock price paid	100%
Employee Stock Option [Member] | Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award
Period of stock granted to employees and executive officers vest in equal installments	7 years
Employee Stock Option [Member] | Measurement Input, Expected Dividend Payment [Member]
Share-based Compensation Arrangement by Share-based Payment Award
Estimated annual dividend amount per share	$ 0.48	$ 0.44
Restricted Stock Units | Employees
Share-based Compensation Arrangement by Share-based Payment Award
Period of stock granted to employees and executive officers vest in equal installments	4 years
Percentage of awards vesting on the first anniversary of grant date	100%
Restricted Stock Units | Director
Share-based Compensation Arrangement by Share-based Payment Award
Period of stock granted to employees and executive officers vest in equal installments	1 year
TSR Performance-Based Restricted Stock Units
Share-based Compensation Arrangement by Share-based Payment Award
Total shareholder return performance measurement period	3 years
Minimum years of service for retirement to be eligible for PRSUs	10 years
Restricted stock unit awards granted	0.1	0.1
Weighted average grant date fair value of restricted stock units granted	$ 102.51	$ 139.04
Stock price		104.12
Weighted average grant date stock price	95.83
TSR Performance-Based Restricted Stock Units | Measurement Input, Expected Dividend Payment [Member]
Share-based Compensation Arrangement by Share-based Payment Award
Estimated annual dividend amount per share	$ 0.48	$ 0.44
TSR Performance-Based Restricted Stock Units | Share-based Compensation Award, Tranche One
Share-based Compensation Arrangement by Share-based Payment Award
Percentage of vesting of target shares upon performance achieved	0%
TSR Performance-Based Restricted Stock Units | Share-based Compensation Award, Tranche Two
Share-based Compensation Arrangement by Share-based Payment Award
Percentage of vesting of target shares upon performance achieved	200%
Employee Stock Purchase Plan | Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award
Period of stock granted to employees and executive officers vest in equal installments	4 years
PBIT Performance-Based Restricted Stock Units
Share-based Compensation Arrangement by Share-based Payment Award
Restricted stock unit awards granted	0.1	0.1
Weighted average grant date fair value of restricted stock units granted	$ 94.51	$ 102.91
Service-Based Restricted Stock Units | Employees
Share-based Compensation Arrangement by Share-based Payment Award
Restricted stock unit awards granted	0.6	0.5
Weighted average grant date fair value of restricted stock units granted	$ 95.98	$ 102.66
Service-Based Restricted Stock Units | Executive Officer
Share-based Compensation Arrangement by Share-based Payment Award
Restricted stock unit awards granted	0.1	0.1
Service-Based Restricted Stock Units | Non Employee Directors
Share-based Compensation Arrangement by Share-based Payment Award
Restricted stock unit awards granted	0.1	0.1
Weighted average grant date fair value of restricted stock units granted	$ 120.38	$ 90.5
Service Based Stock Options | Executive Officer
Share-based Compensation Arrangement by Share-based Payment Award
Weighted average grant date fair value of restricted stock units granted	$ 37.5	$ 41.23

Schedule of Estimated Fair Valu

Schedule of Estimated Fair Value of TSR Performance-Based Restricted Stock Unit Awards Assumptions (Detail) - TSR Performance-Based Restricted Stock Units	9 Months Ended
	Sep. 29, 2024	Oct. 01, 2023
Share-based Compensation Arrangement by Share-based Payment Award
Risk-free interest rate	3.90%	4%
Expected historical volatility	42.40%	49.70%
Dividend yield	0.50%	0.40%
New York Stock Exchange Composite Index
Share-based Compensation Arrangement by Share-based Payment Award
Expected historical volatility	15.60%	24.10%

Schedule of Estimated Fair Va_2

Schedule of Estimated Fair Value of Stock Options Grant Using Black Scholes Option Pricing Model (Detail) - Employee Stock Option [Member]	9 Months Ended
	Sep. 29, 2024	Oct. 01, 2023
Share-based Compensation Arrangement by Share-based Payment Award
Expected life (years)	4 years	4 years
Risk-free interest rate	4%	3.80%
Volatility-historical	46.30%	46.60%
Dividend yield	0.50%	0.40%

Changes in Accumulated Other Co

Changes in Accumulated Other Comprehensive Income (loss) (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 29, 2024	Oct. 01, 2023	Sep. 29, 2024	Oct. 01, 2023
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance	$ 2,730,812	$ 2,434,883	$ 2,525,897	$ 2,451,294
Other comprehensive income (loss)	40,076	(17,456)	22,950	1,940
Balance	2,902,542	2,441,300	2,902,542	2,441,300
Foreign Currency Translation Reclassification Adjustments
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance			(22,442)	(39,849)
Other comprehensive (loss) gain before reclassifications, net of tax			22,751	(2,073)
Amounts reclassified from accumulated other comprehensive income (loss), net of tax			0	0
Other comprehensive income (loss)			22,751	(2,073)
Balance	309	(41,922)	309	(41,922)
Unrealized (Losses) Gains on Marketable Securities
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance			(6,194)	(8,661)
Other comprehensive (loss) gain before reclassifications, net of tax			885	(903)
Amounts reclassified from accumulated other comprehensive income (loss), net of tax			86	33
Other comprehensive income (loss)			971	(870)
Balance	(5,223)	(9,531)	(5,223)	(9,531)
Unrealized (Losses) Gains on Cash Flow Hedges
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance			506	(2,517)
Other comprehensive (loss) gain before reclassifications, net of tax			1,014	6,456
Amounts reclassified from accumulated other comprehensive income (loss), net of tax			(1,780)	(1,567)
Other comprehensive income (loss)			(766)	4,889
Balance	(260)	2,372	(260)	2,372
Retirement Plans Prior Service Credit
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance			1,152	1,159
Other comprehensive (loss) gain before reclassifications, net of tax			0	0
Amounts reclassified from accumulated other comprehensive income (loss), net of tax	(2)	(2)	(6)	(6)
Other comprehensive income (loss)			(6)	(6)
Balance	1,146	1,153	1,146	1,153
Accumulated Other Comprehensive Income (Loss)
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance	(44,104)	(30,472)	(26,978)	(49,868)
Other comprehensive (loss) gain before reclassifications, net of tax			24,650	3,480
Amounts reclassified from accumulated other comprehensive income (loss), net of tax	(9)	(3,093)	(1,700)	(1,540)
Other comprehensive income (loss)	40,076	(17,456)	22,950	1,940
Balance	$ (4,028)	$ (47,928)	$ (4,028)	$ (47,928)

Changes in Accumulated Other _2

Changes in Accumulated Other Comprehensive Income (Loss) (Parenthetical) (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 29, 2024	Oct. 01, 2023	Sep. 29, 2024	Oct. 01, 2023	Dec. 31, 2023	Dec. 31, 2022
Accumulated Other Comprehensive Income (Loss) [Line Items]
Amounts reclassified from accumulated other comprehensive income (loss), tax	$ (2)	$ (869)	$ (477)	$ (433)
Foreign currency translation adjustments, tax	0	0	0	0	$ 0	$ 0
Unrealized (losses) gains on marketable securities, tax	(1,499)	(2,707)	(1,499)	(2,707)	(1,728)	(2,308)
Unrealized (Losses) Gains on Cash Flow Hedges	(73)	667	(73)	667	142	(708)
Retirement plans prior service benefit, tax	(1,133)	(1,131)	(1,133)	(1,131)	$ (1,132)	$ (1,130)
Foreign Currency Translation Reclassification Adjustments
Accumulated Other Comprehensive Income (Loss) [Line Items]
Other comprehensive income (loss) before reclassifications, tax			0	0
Amounts reclassified from accumulated other comprehensive income (loss), tax			0	0
Other comprehensive income (loss), tax			0	0
Unrealized (Losses) Gains on Marketable Securities
Accumulated Other Comprehensive Income (Loss) [Line Items]
Other comprehensive income (loss) before reclassifications, tax			205	(408)
Amounts reclassified from accumulated other comprehensive income (loss), tax	(2)	0	24	9
Other comprehensive income (loss), tax			229	(399)
Unrealized (Losses) Gains on Cash Flow Hedges
Accumulated Other Comprehensive Income (Loss) [Line Items]
Other comprehensive income (loss) before reclassifications, tax			285	1,816
Amounts reclassified from accumulated other comprehensive income (loss), tax			(500)	(441)
Other comprehensive income (loss), tax			(215)	1,375
Retirement Plans Prior Service Credit
Accumulated Other Comprehensive Income (Loss) [Line Items]
Other comprehensive income (loss) before reclassifications, tax			0	0
Amounts reclassified from accumulated other comprehensive income (loss), tax	$ 0	$ 0	(1)	(1)
Other comprehensive income (loss), tax			$ (1)	$ (1)

Reclassifications Out of Accumu

Reclassifications Out of Accumulated Other Comprehensive Income (Loss) to Statements of Operations (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 29, 2024	Oct. 01, 2023	Sep. 29, 2024	Oct. 01, 2023
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Interest income (expense)	$ 7	$ 0	$ (86)	$ (33)
Unrealized (losses) gains, net	0	3,091	1,780	1,567
Accumulated Net Investment Gain (Loss) Attributable to Parent [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Interest income (expense)	7	0	(86)	(33)
Reclassifications, net of tax			(86)	(33)
Amortization of Prior Service Credit
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Reclassifications, net of tax	2	2	6	6
Accumulated Other Comprehensive Income (Loss)
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Reclassifications, net of tax	$ 9	$ 3,093	$ 1,700	$ 1,540

Reclassifications Out of Accu_2

Reclassifications Out of Accumulated Other Comprehensive Income (Loss) to Statements of Operations (Parenthetical) (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 29, 2024	Oct. 01, 2023	Sep. 29, 2024	Oct. 01, 2023
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), Reclassification, Tax	$ 0	$ 869	$ 500	$ 441
Reclassifications, tax	2	869	477	433
Unrealized (Losses) Gains on Marketable Securities
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Reclassifications, tax	2	0	(24)	(9)
Amortization of Prior Service Credit
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Reclassifications, tax	$ 0	$ 0	$ 1	$ 1

Goodwill and Acquired Intangi_3

Goodwill and Acquired Intangible Assets - Additional Information (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 29, 2024	Oct. 01, 2023	Sep. 29, 2024	Oct. 01, 2023
Goodwill and Intangible Assets Disclosure [Line Items]
Acquired intangible assets amortization	$ 4,748	$ 4,720	$ 14,108	$ 14,348

Changes in Carrying Amount of G

Changes in Carrying Amount of Goodwill by Segment (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Sep. 29, 2024
Goodwill [Line Items]
Goodwill	$ 1,178,218	$ 1,181,978
Accumulated impairment losses	(762,566)	(762,566)
Foreign currency translation adjustment	3,760
Total Goodwill	415,652	419,412
Robotics
Goodwill [Line Items]
Goodwill	395,463	399,229
Accumulated impairment losses	0	0
Foreign currency translation adjustment	3,765
Total Goodwill	395,463	399,229
Wireless Test
Goodwill [Line Items]
Goodwill	361,819	361,819
Accumulated impairment losses	(353,843)	(353,843)
Foreign currency translation adjustment	0
Total Goodwill	7,976	7,976
Semiconductor Test
Goodwill [Line Items]
Goodwill	262,237	262,232
Accumulated impairment losses	(260,540)	(260,540)
Foreign currency translation adjustment	(5)
Total Goodwill	1,697	1,692
System Test
Goodwill [Line Items]
Goodwill	158,699	158,699
Accumulated impairment losses	(148,183)	(148,183)
Foreign currency translation adjustment	0
Total Goodwill	$ 10,516	$ 10,516

Schedule of Amortizable Intangi

Schedule of Amortizable Intangible Assets (Detail) - USD ($) $ in Thousands	9 Months Ended	12 Months Ended
	Sep. 29, 2024	Dec. 31, 2023
Finite-Lived Intangible Assets
Gross Carrying Amount	$ 378,822	$ 378,822
Accumulated Amortization	(351,158)	(337,062)
Foreign Currency Translation Adjustment	(6,376)	(6,356)
Net Carrying Amount	21,288	35,404
Developed technology
Finite-Lived Intangible Assets
Gross Carrying Amount	267,706	267,706
Accumulated Amortization	(252,406)	(243,191)
Foreign Currency Translation Adjustment	(5,337)	(5,343)
Net Carrying Amount	9,963	19,172
Customer Relationships
Finite-Lived Intangible Assets
Gross Carrying Amount	52,109	52,109
Accumulated Amortization	(49,134)	(47,850)
Foreign Currency Translation Adjustment	210	232
Net Carrying Amount	3,185	4,491
Trademarks and tradenames
Finite-Lived Intangible Assets
Gross Carrying Amount	59,007	59,007
Accumulated Amortization	(49,618)	(46,021)
Foreign Currency Translation Adjustment	(1,249)	(1,245)
Net Carrying Amount	$ 8,140	$ 11,741

Schedule of Estimated Intangibl

Schedule of Estimated Intangible Asset Amortization Expense (Detail) $ in Thousands	Sep. 29, 2024 USD ($)
Finite-Lived Intangible Assets
2024	$ 4,775
2025	11,454
2026	2,402
2027	1,185
2028	1,104
Thereafter	$ 368

Net Income Per Common Share - A

Net Income Per Common Share - Additional Information (Detail) - shares shares in Millions	3 Months Ended		9 Months Ended
	Sep. 29, 2024	Oct. 01, 2023	Sep. 29, 2024	Oct. 01, 2023
Employee Stock Option [Member]
Net Income Loss Per Common Share
Exercise of stock options	0.1	0.1	0.5	0.4

Computation of Basic and Dilute

Computation of Basic and Diluted Net Income Per Common Share (Detail) - USD ($) $ / shares in Units, $ in Thousands		3 Months Ended		9 Months Ended
		Sep. 29, 2024	Oct. 01, 2023	Sep. 29, 2024	Oct. 01, 2023
Net Income Loss Per Common Share
Net Income (Loss)		$ 145,649	$ 128,116	$ 396,119	$ 331,698
Weighted average common shares-basic		163,002,000	153,762,000	157,951,000	154,809,000
Convertible note hedge warrant shares	[1]	460,000	9,168,000	4,751,000	9,009,000
Incremental shares from assumed conversion of convertible notes	[2]	0	629,000	0	762,000
Incremental Common Shares Attributable to Dilutive Effect of Equity Unit Purchase Agreements		10,000	10,000	5	8
Weighted Average Number of Shares Outstanding, Diluted, Adjustment, Total		1,251,000	10,288,000	5,406,000	10,228,000
Weighted average common shares-diluted		164,253,000	164,050,000	163,357,000	165,037,000
Earnings Per Share, Basic		$ 0.89	$ 0.83	$ 2.51	$ 2.14
Earnings Per Share, Diluted		$ 0.89	$ 0.78	$ 2.42	$ 2.01
Restricted Stock Units
Net Income Loss Per Common Share
Incremental shares attributable to share based payment arrangements		768,000	455,000	637	410
Employee Stock Option [Member]
Net Income Loss Per Common Share
Incremental shares attributable to share based payment arrangements		13,000	26,000	13	39
[1] Convertible notes hedge warrant shares were calculated using the difference between the average Teradyne stock price for the period and the warrant price, multiplied by the number of warrant shares. The result of this calculation, representing the total intrinsic value of the warrant, was divided by the average Teradyne stock price for the period. Incremental shares from assumed conversion of the convertible notes were calculated using the difference between the average Teradyne stock price for the period and the conversion price, multiplied by the number of convertible notes shares. The result of this calculation, representing the total intrinsic value of the convertible notes, was divided by the average Teradyne stock price for the period.

Restructuring and Other - Addit

Restructuring and Other - Additional Information (Detail) $ in Millions	3 Months Ended		6 Months Ended	9 Months Ended
	Sep. 29, 2024 USD ($)	Oct. 01, 2023 USD ($) HeadCount	Jul. 02, 2023 HeadCount	Sep. 29, 2024 USD ($) HeadCount	Oct. 01, 2023 USD ($)
Restructuring Cost and Reserve
Severance benefit and charges	$ 0.3	$ 4.7		$ 5.3	$ 11.8
Number of severance charges related to headcount reductions | HeadCount		94	197	87
Contract termination charge		$ 1.5			1.5
Increase in environmental liability others					$ 1.1
Technoprobe [Member]
Restructuring Cost and Reserve
Acquisition and divestiture expenses				$ 2.2

Retirement Plans - Additional I

Retirement Plans - Additional Information (Detail) $ in Millions	3 Months Ended	9 Months Ended
	Sep. 29, 2024 USD ($) RetireeParticipants	Sep. 29, 2024 USD ($) RetireeParticipants	Oct. 01, 2023 USD ($)
U.S. Supplemental Executive Defined Benefit Pension Plan
Defined Benefit Plan Disclosure
Contribution to defined benefit pension plans		$ 2.3	$ 2.3
Non-United States Subsidiaries
Defined Benefit Plan Disclosure
Contribution to defined benefit pension plans in 2018	$ 0.8	$ 0.8	$ 0.8
Group Annuity Contract | U.S. Qualified Pension Plan
Defined Benefit Plan Disclosure
Retiree participants transferred to accrued pension obligation | RetireeParticipants	132	132
Reduction in pension benefit obligation and pension assets	$ 23.4
Settlement expense	$ 0.4	$ 0.4

Schedule of Net Periodic Pensio

Schedule of Net Periodic Pension and Postretirement (income) Cost (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 29, 2024	Oct. 01, 2023	Sep. 29, 2024	Oct. 01, 2023
Defined Benefit Plan Disclosure
Net actuarial loss (gain)			$ (2,512)	$ 0
United States
Defined Benefit Plan Disclosure
Service cost	$ 216	$ 272	665	815
Interest cost	1,590	1,713	4,883	5,138
Expected return on plan assets	(1,204)	(1,286)	(3,737)	(3,856)
Net actuarial loss (gain)	(2,262)	0	(2,151)	24
Settlement expense	394	0	394	0
Total net periodic pension cost	(1,266)	699	54	2,121
Foreign Pension Plans, Defined Benefit
Defined Benefit Plan Disclosure
Service cost	119	107	360	320
Interest cost	256	253	766	762
Expected return on plan assets	(23)	(11)	(58)	(28)
Net actuarial loss (gain)	0	66	(242)	66
Settlement expense	0	5	(24)	5
Total net periodic pension cost	352	420	802	1,125
Postretirement Benefit Plans
Defined Benefit Plan Disclosure
Service cost	9	9	28	26
Interest cost	72	60	217	181
Net actuarial loss (gain)	0	0	(94)	30
Amortization of prior service credit	(2)	(2)	(7)	(7)
Special termination benefits	0	1,423	462	1,792
Total net periodic pension cost	$ 79	$ 1,490	$ 606	$ 2,022

Commitments and Contingencies -

Commitments and Contingencies - Additional Information (Detail) - USD ($) $ in Millions	9 Months Ended	12 Months Ended
	Sep. 29, 2024	Dec. 31, 2023
Purchase Commitment, Excluding Long-term Commitment
Aggregate purchase commitments	$ 458.1
Purchase commitments less than one year	445.9
Product warranty accrual	13.9	$ 15.7
Revenue deferrals related to extended warranties	$ 38.9	$ 34.9

Income Taxes - Additional Infor

Income Taxes - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Thousands			3 Months Ended		9 Months Ended
	Dec. 15, 2022	Aug. 16, 2022	Sep. 29, 2024	Oct. 01, 2023	Sep. 29, 2024	Oct. 01, 2023	Dec. 31, 2023
Income Taxes [Line Items]
Decrease in Unrecognised Tax Benefit due to lapse in Statute of limitation					$ 700
Accrued interest and penalties			$ 200		200		$ 1,300
Interest and penalties related to income tax, expense (benefit)					(1,000)	$ 200
Uncertain tax positions			7,600		7,600		$ 18,600
Net increase in uncertain tax positions					(11,000)
Percentage of alternative minimum tax		15%
Minimum effective tax rate	15%
Gain on sale of a business			0	$ 0	57,486	0
Income tax expense			$ 12,260	$ 16,164	54,095	$ 54,069
Device Interface Solutions
Income Taxes [Line Items]
Gain on sale of a business					57,500
Income tax expense					$ 10,700
SINGAPORE
Income Taxes [Line Items]
Tax savings due to the tax holiday, per share					$ 0.06	$ 0.01
Income Tax Holiday, Aggregate Dollar Amount					$ 10,200	$ 1,700

Schedule of Reconciliation of E

Schedule of Reconciliation of Effective Tax Rate (Detail)	3 Months Ended		9 Months Ended
	Sep. 29, 2024	Oct. 01, 2023	Sep. 29, 2024	Oct. 01, 2023
Income Tax Disclosure [Line Items]
U.S. statutory federal tax rate	21%	21%	21%	21%
Non-deductible officers' compensation	0.50%	1.30%	0.40%	1.10%
Tax credits	(5.00%)	(9.30%)	(3.60%)	(5.00%)
Discrete expense (benefit) related to reserves for uncertain tax positions	(4.90%)	0.30%	(2.20%)	0.10%
Foreign taxes	(4.90%)	(1.50%)	(3.30%)	(1.10%)
International provisions of the U.S. Tax Cuts and Jobs Act of 2017	(0.80%)	(3.10%)	(1.10%)	(2.90%)
Other, net	1.90%	2.50%	0.80%	0.80%
Effective tax rate	7.80%	11.20%	12%	14%

Segment Information - Additiona

Segment Information - Additional Information (Detail)	9 Months Ended
	Sep. 29, 2024 Segment
Segment Reporting Information [Line Items]
Operating segments	4

Schedule of Segment Information

Schedule of Segment Information (Detail) - USD ($) $ in Thousands		3 Months Ended				9 Months Ended
		Sep. 29, 2024		Oct. 01, 2023		Sep. 29, 2024		Oct. 01, 2023		Dec. 31, 2023
Segment Reporting Information [Line Items]
Revenues		$ 737,298	[1]	$ 703,732	[1]	$ 2,066,996	[2]	$ 2,005,699	[2]
Income (loss) before income taxes	[3],[4]	158,984		144,280		451,289		385,767
Total assets		3,769,728	[5]	3,370,655	[5]	3,769,728	[5]	3,370,655	[5]	$ 3,486,824
System Test
Segment Reporting Information [Line Items]
Revenues		73,312	[1]	83,203	[1]	209,435	[2]	252,106	[2]
Wireless Test
Segment Reporting Information [Line Items]
Revenues		32,601	[1]	36,974	[1]	93,457	[2]	119,472	[2]
Operating Segments
Segment Reporting Information [Line Items]
Revenues		737,298		703,732		2,066,996		2,005,699
Income (loss) before income taxes	[3],[4]	156,373		147,862		394,869		393,442
Total assets	[5]	2,357,481		2,338,069		2,357,481		2,338,069
Operating Segments | Semiconductor Test
Segment Reporting Information [Line Items]
Revenues		542,734		497,863		1,497,552		1,387,580
Income (loss) before income taxes	[3],[4]	163,778		136,451		401,475		361,676
Total assets	[5]	1,308,031		1,382,444		1,308,031		1,382,444
Operating Segments | System Test
Segment Reporting Information [Line Items]
Revenues		73,312		83,203		209,435		252,106
Income (loss) before income taxes	[3],[4]	12,522		23,754		36,138		67,629
Total assets	[5]	178,291		178,904		178,291		178,904
Operating Segments | Robotics
Segment Reporting Information [Line Items]
Revenues		88,651		85,692		266,552		246,541
Income (loss) before income taxes	[3],[4]	(24,206)		(21,812)		(56,099)		(66,704)
Total assets	[5]	794,277		684,207		794,277		684,207
Operating Segments | Wireless Test
Segment Reporting Information [Line Items]
Revenues		32,601		36,974		93,457		119,472
Income (loss) before income taxes	[3],[4]	4,279		9,469		13,355		30,841
Total assets	[5]	76,882		92,514		76,882		92,514
Corporate And Eliminations
Segment Reporting Information [Line Items]
Revenues		0		0		0		0
Income (loss) before income taxes	[3],[4]	2,611		(3,582)		56,420		(7,675)
Total assets	[5]	$ 1,412,247		$ 1,032,586		$ 1,412,247		$ 1,032,586
[1] Include s $ 0.8 million and $ 1.4 million in 2024, and 2023, respectively, for leases of Teradyne’s systems recognized outside Accounting Standards Codification (“ASC”) 606 “Revenue from Contracts with Customers.” Includes $ 2.5 million and $ 3.9 million in 2024 and 2023, respectively, for leases of Teradyne’s systems recognized outside Accounting Standards Codification (“ASC”) 606 “Revenue from Contracts with Customers.” Included in Corporate and Eliminations are interest income, interest expense, net foreign exchange gains (losses), intercompany eliminations, severance charges, pension, acquisition and divestiture related fees, and an expense for the modification of outstanding equity awards. Included in income (loss) before taxes are charges related to restructuring and other, expense for the modification of outstanding equity awards, legal settlement, pension mark-to-market, and inventory charges. Total assets are attributable to each segment. Corporate assets consist of cash and cash equivalents, marketable securities, and certain other assets.

Schedule of Segment Reporting I

Schedule of Segment Reporting Information by Segment Charges (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 29, 2024	Oct. 01, 2023	Sep. 29, 2024	Oct. 01, 2023
Segment Reporting Information [Line Items]
Restructuring and other—employee severance	$ 4,578	$ 6,856	$ 11,018	$ 15,251
Semiconductor Test
Segment Reporting Information [Line Items]
Cost of revenues—inventory charge	4,041	10,422	11,405	18,374
Restructuring and other—employee severance	0	1,776	1,277	5,055
System Test
Segment Reporting Information [Line Items]
Cost of revenues—inventory charge	0	0	1,016	1,412
Restructuring and other—employee severance	0	0	0	1,124
Robotics
Segment Reporting Information [Line Items]
Cost of revenues-legal settlement	3,600	0	3,600	0
Cost of revenues—inventory charge	537	652	1,071	2,203
Restructuring and other—employee severance	1,110	636	2,647	2,707
Wireless
Segment Reporting Information [Line Items]
Cost of revenues—inventory charge	1,204	0	2,024	1,080
Corporate And Eliminations
Segment Reporting Information [Line Items]
Restructuring and other-acquisition & divestiture related expenses	0	0	2,214	0
Selling and administrative-equity modification	0	0	1,469	5,889
Restructuring and other—employee severance	0	1,753	0	2,877
Restructuring and other-contract termination	0	1,511	0	1,511
Restructuring and other—other	$ 2,437	$ 0	$ 2,437	$ 1,100

Shareholders' Equity - Addition

Shareholders' Equity - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Thousands, shares in Millions		3 Months Ended		9 Months Ended
	Jan. 01, 2023	Sep. 29, 2024	Oct. 01, 2023	Sep. 29, 2024	Oct. 01, 2023	Aug. 31, 2024	May 31, 2024	Jan. 31, 2024	Aug. 31, 2023	May 31, 2023	Jan. 31, 2023
Common stock average price				$ 111.32	$ 103.89
Dividends Payable, Amount Per Share						$ 0.12	$ 0.12	$ 0.12	$ 0.11	$ 0.11	$ 0.11
Dividend payment				$ 56,936	$ 51,081
Percentage of excise tax on share repurchases in excess of issuances	1%
Cumulative repurchases, shares		0.5	3.4	0.5	3.4
Cumulative repurchases, value		$ 55,100	$ 349,300	$ 55,100	$ 349,300						$ 2,000,000
Common Stock
Dividend payment		$ 19,600	$ 16,900	$ 57,000	$ 51,100
2023 Repurchase Program [Member]
Common stock average price				$ 103.46
Cumulative repurchases, shares		4.4		4.4
Cumulative repurchases, value		$ 455,600		$ 455,600