Teradyne (TER) 10-K 22 Feb 24 2023 FY Annual report Financial data

Cover Page

Cover Page - USD ($) $ in Billions	12 Months Ended
	Dec. 31, 2023	Feb. 16, 2024	Jul. 02, 2023
Cover [Abstract]
Amendment Flag	false
Document Type	10-K
Document Fiscal Year Focus	2023
Entity Central Index Key	0000097210
Document Fiscal Period Focus	FY
Current Fiscal Year End Date	--12-31
Entity Well-known Seasoned Issuer	Yes
Entity Voluntary Filers	No
Document Period End Date	Dec. 31, 2023
Entity Registrant Name	TERADYNE, INC.
Entity Filer Category	Large Accelerated Filer
Entity Public Float			$ 11
Trading Symbol	TER
Document Annual 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		153,080,607
ICFR Auditor Attestation Flag	true
Auditor Name	PricewaterhouseCoopers LLP
Auditor Firm ID	238
Auditor Location	Boston, Massachusetts
Document Financial Statement Error Correction [Flag]	false

CONSOLIDATED BALANCE SHEETS

CONSOLIDATED BALANCE SHEETS - USD ($) $ in Thousands		Dec. 31, 2023		Dec. 31, 2022
Current assets:
Cash and cash equivalents		$ 757,571		$ 854,773
Marketable securities		62,154		39,612
Accounts receivable, less allowance for credit losses of $1,988 and $1,955 in 2023 and 2022, respectively		422,124		491,145
Inventories, net		309,974	[1]	325,019
Prepayments		548,970	[2]	532,962
Other current assets		37,992		14,404
Current assets held for sale		23,250		0
Total current assets		2,162,035		2,257,915
Property, plant and equipment, net		445,492	[3]	418,683
Operating lease right-of-use assets, net		73,417		73,734
Marketable securities		117,434		110,777
Deferred tax assets		175,775		142,784
Retirement plans assets		11,504		11,761
Other assets		38,580		28,925
Acquired intangible assets, net		35,404		53,478
Goodwill		415,652		403,195
Long-term assets held for sale		11,531		0
Total assets	[4]	3,486,824		3,501,252
Current liabilities:
Accounts payable		180,131		139,722
Accrued employees' compensation and withholdings		191,750		212,266
Deferred revenue and customer advances		99,804		148,285
Other accrued liabilities		114,712		112,271
Operating lease liabilities		17,522		18,594
Income taxes payable		48,653		65,010
Current debt		0		50,115
Current liabilities held for sale		7,379		0
Total current liabilities		659,951		746,263
Retirement plans liabilities		132,090		116,005
Long-term deferred revenue and customer advances		37,282		45,131
Deferred tax liabilities		183		3,267
Long-term other accrued liabilities		19,998		15,981
Long-term operating lease liabilities		65,092		64,176
Long-term incomes taxes payable		44,331		59,135
Long-term liabilities held for sale		2,000		0
Total liabilities		960,927		1,049,958
Commitments and contingencies (Note M)
SHAREHOLDERS' EQUITY
Common stock, $0.125 par value, 1,000,000 shares authorized, 152,698 and 155,759 shares issued and outstanding at December 31, 2023 and 2022, respectively		19,087		19,470
Additional paid-in capital		1,827,274		1,755,963
Accumulated other comprehensive loss		(26,978)		(49,868)
Retained earnings		706,514		725,729
Total shareholders' equity		2,525,897		2,451,294
Total liabilities, convertible common shares and shareholders' equity		$ 3,486,824		$ 3,501,252
[1] Excludes $ 18.0 million of primarily work-in-process inventories, net classified as assets held for sale. See Note E: “Assets held for sale” for additional information. Excludes $ 5.3 million of contract manufacturer and supplier prepayments, classified as assets held for sale. See Note E: “Assets held for sale” for additional information. Excludes $ 9.0 million of property, plant and equipment, net classified as assets held for sale. See Note E: “Assets held for sale” for additional information. Total assets are attributable to each segment. Semiconductor Test includes $ 34.8 million of total assets classified as assets held for sale. See Note E: “Assets held for sale” for additional information. Corporate assets consist of cash and cash equivalents, marketable securities and certain other assets.

CONSOLIDATED BALANCE SHEETS (Pa

CONSOLIDATED BALANCE SHEETS (Parenthetical) - USD ($) shares in Thousands, $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Statement of Financial Position [Abstract]
Accounts receivable, less allowance for doubtful accounts	$ 1,988	$ 1,955
Common stock, par value	$ 0.125	$ 0.125
Common stock, shares authorized	1,000,000	1,000,000
Common stock, shares issued	152,698	155,759
Common stock, shares outstanding	152,698	155,759

CONSOLIDATED STATEMENTS OF OPER

CONSOLIDATED STATEMENTS OF OPERATIONS - USD ($) shares in Thousands, $ in Thousands		12 Months Ended
		Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Revenues:
Total revenues	[1],[2]	$ 2,676,298	$ 3,155,045	$ 3,702,881
Cost of revenues:
Total cost of revenues (exclusive of acquired intangible assets amortization shown separately below)		1,139,550	1,287,894	1,496,225
Gross profit		1,536,748	1,867,151	2,206,656
Operating expenses:
Selling and administrative		577,315	558,103	547,559
Engineering and development		418,089	440,591	427,609
Acquired intangible assets amortization		18,999	19,333	21,456
Restructuring and other		21,277	17,185	9,312
Total operating expenses		1,035,680	1,035,212	1,005,936
Income from operations		501,068	831,939	1,200,720
Non-operating (income) expenses:
Interest income		(27,348)	(6,379)	(2,627)
Interest expense		3,806	3,719	17,820
Other (income) expense, net		(962)	(5,786)	24,572
Income before income taxes	[3],[4]	525,572	840,385	1,160,955
Income tax provision		76,820	124,884	146,366
Net income		$ 448,752	$ 715,501	$ 1,014,589
Net income per common share:
Basic		$ 2.91	$ 4.52	$ 6.15
Diluted		$ 2.73	$ 4.22	$ 5.53
Weighted average common shares—basic		154,310	158,434	164,960
Weighted average common shares—diluted		164,304	169,734	183,625
Product [Member]
Revenues:
Total revenues		$ 2,096,286	$ 2,591,572	$ 3,196,575
Cost of revenues:
Total cost of revenues (exclusive of acquired intangible assets amortization shown separately below)		882,892	1,042,555	1,300,106
Service [Member]
Revenues:
Total revenues		580,012	563,473	506,306
Cost of revenues:
Total cost of revenues (exclusive of acquired intangible assets amortization shown separately below)		$ 256,658	$ 245,339	$ 196,119
[1] Includes $ 5.2 m illion, $ 8.2 million and $ 13.2 million in 2023, 2022 and 2021, respectively, for leases of Teradyne’s systems recognized outside of ASC 606: “Revenue from Contracts with Customers.” Revenues attributable to a country are based on location of customer site. Included in Corporate and Eliminations are interest income, interest expense, net foreign exchange gains (losses), intercompany eliminations, pension and postretirement plan actuarial gains (losses), legal and environmental fees, contingent consideration adjustments, acquisition and divestiture related expenses, contract termination settlement charge, an expense for the modification of Teradyne's former chief executive officer's outstanding equity awards, and loss on convertible debt conversions in 2021. Included in income (loss) before taxes are charges and credits related to restructuring and other, inventory charges and loss on convertible debt conversions in 2021.

CONSOLIDATED STATEMENTS OF COMP

CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Statement of Comprehensive Income [Abstract]
Net income	$ 448,752	$ 715,501	$ 1,014,589
Other comprehensive income (loss), net of tax:
Foreign currency translation adjustment, net of tax of $0, $0, $0, respectively	17,407	(29,031)	(36,207)
Available-for-sale marketable securities:
Unrealized gains (losses) on marketable securities arising during period, net of tax of $568, $(3,388), ($578), respectively	2,423	(12,666)	(2,255)
Less: Reclassification adjustment for losses (gains) included in net income, net of tax of $12, $25, $(277), respectively	44	301	(995)
Other Comprehensive Income (Loss), Available-for-sale Securities Adjustment, Net of Tax, Total	2,467	(12,365)	(3,250)
Cash flow hedges:
Unrealized gains (losses) arising during period, net of tax of $1,537, $(708), $0, respectively	5,464	(2,517)	0
Less: Reclassification adjustment for losses included in net income, net of tax of $(686), $0, $0, respectively	(2,441)	0	0
Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), after Reclassification and Tax, Parent	3,023	(2,517)	0
Defined benefit post-retirement plan:
Amortization of prior service credit, net of tax $(2), $(2), $(2), respectively	(7)	(7)	(7)
Other comprehensive income (loss)	22,890	(43,920)	(39,464)
Comprehensive income	$ 471,642	$ 671,581	$ 975,125

CONSOLIDATED STATEMENTS OF CO_2

CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (Parenthetical) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Statement of Comprehensive Income [Abstract]
Foreign currency translation adjustments, tax	$ 0	$ 0	$ 0
Unrealized gains (losses) on marketable securities arising during period, net of tax	568	(3,388)	(578)
Reclassification adjustment for losses (gains) included in net income, net of tax	12	25	(277)
Amortization of prior service credit, net of tax	(2)	(2)	(2)
Cash flow hedges Unrealized gains (losses)	1,537	(708)	0
Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), Reclassification, Tax	$ (686)	$ 0	$ 0

CONSOLIDATED STATEMENTS OF CONV

CONSOLIDATED STATEMENTS OF CONVERTIBLE COMMON SHARES AND SHAREHOLDERS' EQUITY - USD ($) $ in Thousands	Total	Common Stock	Common Stock Convertible Common Shares	Additional Paid-in Capital	Accumulated Other Comprehensive Income (loss)	Retained Earnings
Balance at Dec. 31, 2020	$ 2,207,018	$ 20,765		$ 1,765,323	$ 33,516	$ 387,414
Balance, Shares at Dec. 31, 2020		166,123,000	3,787,000
Net issuance of common stock under stock-based plans	(112)	$ 113		(225)
Net issuance of common stock under stock-based plans (in shares)		899,000
Stock-based compensation expense	45,632			45,632
Repurchase of common stock	(600,000)	$ (597)				(599,403)
Repurchase of common stock (in shares)		(4,771,000)
Cash dividends	(66,034)					(66,034)
Settlements of convertible notes	985,640	$ 1,018		984,622
Settlement of convertible notes (in shares)		8,148,000
Exercise of convertible notes hedge call options	(987,100)	$ (1,018)		(986,082)
Exercise of convertible notes hedge call options (in shares)		(8,148,000)
Convertible common shares	2,275			2,275
Convertible common shares (in shares)			(2,275,000)
Net income	1,014,589					1,014,589
Other comprehensive income (loss)	(39,464)				(39,464)
Balance at Dec. 31, 2021	2,562,444	$ 20,281		1,811,545	(5,948)	736,566
Balance, Shares at Dec. 31, 2021		162,251,000	1,512,000
Net issuance of common stock under stock-based plans	(4,375)	$ 96		(4,471)
Net issuance of common stock under stock-based plans (in shares)		761,000
Stock-based compensation expense	48,466			48,466
Repurchase of common stock	(752,082)	$ (907)				(751,175)
Repurchase of common stock (in shares)		(7,253,000)
Cash dividends	(69,763)					(69,763)
Settlements of convertible notes	(255)	$ 187		(442)
Settlement of convertible notes (in shares)		1,495,000
Exercise of convertible notes hedge call options	0	$ (187)		187
Exercise of convertible notes hedge call options (in shares)		(1,495,000)
Convertible common shares	1,512			1,512
Convertible common shares (in shares)			(1,512,000)
Cumulative effect of change in accounting principle related to convertible debt	(6,234)			(100,834)		94,600
Net income	715,501					715,501
Other comprehensive income (loss)	(43,920)				(43,920)
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	0
Net issuance of common stock under stock-based plans	13,477	$ 106		13,371
Net issuance of common stock under stock-based plans (in shares)		848,000
Stock-based compensation expense	57,940			57,940
Repurchase of common stock	(400,529)	$ (489)				(400,040)
Repurchase of common stock (in shares)		(3,909,000)
Cash dividends	(67,927)					(67,927)
Settlements of convertible notes	0	$ 133		(133)
Settlement of convertible notes (in shares)		1,072,000
Exercise of convertible notes hedge call options	0	$ (133)		133
Exercise of convertible notes hedge call options (in shares)		(1,072,000)
Net income	448,752					448,752
Other comprehensive income (loss)	22,890				22,890
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	0

CONSOLIDATED STATEMENTS OF CO_3

CONSOLIDATED STATEMENTS OF CONVERTIBLE COMMON SHARES AND SHAREHOLDERS' EQUITY (Parenthetical) - $ / shares	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Statement of Stockholders' Equity [Abstract]
Common Stock, Dividends, Per Share, Cash Paid	$ 0.44	$ 0.44	$ 0.4

CONSOLIDATED STATEMENTS OF CASH

CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Cash flows from operating activities:
Net income	$ 448,752	$ 715,501	$ 1,014,589
Adjustments to reconcile net income from operations to net cash provided by operating activities:
Depreciation	92,118	90,763	91,073
Stock-based compensation	57,682	48,228	45,643
Provision for excess and obsolete inventory	28,358	31,452	15,475
Amortization	18,768	19,912	34,412
Retirement plans actuarial losses (gains)	2,703	(25,584)	(2,217)
Deferred taxes	(37,642)	(38,693)	(17,305)
(Gains) losses on investments	(14,915)	9,985	(6,410)
Gains on sale of asset	0	(3,410)	0
Loss on convertible debt conversion	0	0	28,828
Contingent consideration adjustment	0	0	(7,227)
Other	(955)	2,353	271
Changes in operating assets and liabilities, net of businesses acquired:
Accounts receivable	70,977	50,628	(57,778)
Inventories	5,327	(80,809)	6,495
Prepayments and other assets	(43,101)	(140,713)	(175,846)
Accounts payable and other accrued expenses	46,782	(60,507)	129,499
Deferred revenue and customer advances	(57,210)	(6,233)	9,873
Retirement plans contributions	(5,492)	(5,116)	(5,405)
Income taxes	(26,921)	(29,834)	(5,604)
Net cash provided by operating activities	585,231	577,923	1,098,366
Cash flows from investing activities:
Purchases of property, plant and equipment	(159,642)	(163,249)	(132,472)
Purchases of marketable securities	(161,906)	(287,409)	(661,781)
Proceeds from maturities of marketable securities	85,042	222,941	660,148
Proceeds from sales of marketable securities	61,401	268,058	266,466
Proceeds from insurance	460	0	0
Issuance of convertible loan	(5,000)	0	0
Proceeds from sale of asset	0	3,410	0
Purchase of investment and acquisition of business	0	0	(12,000)
Net cash (used for) provided by investing activities	(179,645)	43,751	120,361
Cash flows from financing activities:
Repurchase of common stock	(397,241)	(752,082)	(600,000)
Dividend payments	(67,878)	(69,711)	(65,977)
Payments of convertible debt principal	(50,264)	(66,759)	(342,990)
Payments related to net settlement of employee stock compensation awards	(20,788)	(33,170)	(32,303)
Issuance of common stock under stock purchase and stock option plans	34,259	28,733	32,686
Net cash used for financing activities	(501,912)	(892,989)	(1,008,584)
Effects of exchange rate changes on cash and cash equivalents	(876)	3,889	(2,065)
(Decrease) Increase in cash and cash equivalents	(97,202)	(267,426)	208,078
Cash and cash equivalents at beginning of year	854,773	1,122,199	914,121
Cash and cash equivalents at end of year	757,571	854,773	1,122,199
Cash paid for:
Interest	296	1,498	4,236
Income taxes	140,239	193,246	172,134
Non-cash investing activities:
Capital expenditures incurred but not yet paid:	$ 2,735	$ 1,826	$ 1,973

Pay vs Performance Disclosure

Pay vs Performance Disclosure - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Pay vs Performance Disclosure
Net Income (Loss)	$ 448,752	$ 715,501	$ 1,014,589

Insider Trading Arrangements

Insider Trading Arrangements	3 Months Ended
	Dec. 31, 2023
Trading Arrangements, by Individual
Rule 10b5-1 Arrangement Adopted	false
Rule 10b5-1 Arrangement Terminated	false
Rule 10b5-1 Arrangement Modified Flag	false

The Company

The Company	12 Months Ended
	Dec. 31, 2023
Organization, Consolidation and Presentation of Financial Statements [Abstract]
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 (“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	12 Months Ended
	Dec. 31, 2023
Accounting Policies [Abstract]
Accounting Policies	B. ACCOUNTING POLICIES The consolidated financial statements include the accounts of Teradyne and its wholly owned subsidiaries. All significant intercompany balances and transactions are eliminated. Certain prior years’ amounts were reclassified to conform to the current year presentation. 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 Annual Report on Form 10-K. 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. Revenue Recognition Revenue from Contracts with Customers In accordance with ASC 606, Teradyne recognizes revenues, when or as control is transferred to a customer. Teradyne’s determination of revenue is dependent upon a five-step process outlined below. • Teradyne accounts for a contract with a customer when there is written approval, the contract is committed, the rights of the parties, including payment terms, are identified, the contract has commercial substance and consideration is probable of collection. • Teradyne periodically enters into contracts with customers in which a customer may purchase a combination of goods and services, such as products with extended warranty obligations. Teradyne determines performance obligations by assessing whether the products or services are distinct from the other elements of the contract. In order to be distinct, the product or service must perform either on its own or with readily available resources and must be separate within the context of the contract. • Teradyne determines the transaction price to be the amount of consideration to which Teradyne expects to be entitled to, which is generally at contractually stated prices. • Transaction price is allocated to each individual performance obligation based on the standalone selling price of that performance obligation. Teradyne uses standalone transactions when available to value each performance obligation. If standalone transactions are not available, Teradyne will estimate the standalone selling price through market assessments or cost plus a reasonable margin analysis. Any discounts from standalone selling price are spread proportionally to each performance obligation. • In order to determine the appropriate timing for revenue recognition, Teradyne first determines if the transaction meets any of three criteria for over time recognition. If the transaction meets the criteria for over time recognition, Teradyne recognizes revenue as the good or service is delivered. Teradyne uses input variables such as hours or months utilized or costs incurred to determine the amount of revenue to recognize in a given period. Input variables are used as they best align consumption with benefit to the customer. For transactions that do not meet the criteria for over time recognition, Teradyne will recognize revenue at a point in time based on an assessment of the five criteria for transfer of control. Teradyne has concluded that revenue should be recognized when shipped or delivered based on contractual terms. Typically, acceptance of Teradyne’s products and services is a formality as Teradyne delivers similar systems, instruments and robots to standard specifications. In cases where acceptance is not deemed a formality, Teradyne will defer revenue recognition until customer acceptance. Performance Obligations Products Teradyne products consist primarily of semiconductor test systems and instruments, defense/aerospace test instrumentation and systems, storage test systems and instruments, circuit-board test and inspection systems and instruments, wireless test systems and robotics products. Teradyne’s hardware is typically recognized at a point in time upon transfer of control to the customer. Services Teradyne services consist of extended warranties, training and application support, service agreements, post contract customer support (“PCS”) and replacement parts. Each service is recognized based on relative standalone selling price. Extended warranty, training and support, service agreements and PCS are recognized over time based on the period of service. Replacement parts are recognized at a point in time upon transfer of control to the customer. Teradyne does not allow customer returns or provide refunds to customers for any products or services. Teradyne products include a standard 12 -month warranty. This warranty is not considered a distinct performance obligation because it does not obligate Teradyne to provide a separate service to the customer and it cannot be purchased separately. Cost related to warranties are included in cost of revenues when product revenues are recognized. As of December 31, 2023 and 2022, deferred revenue and customer advances consisted of the following and are included in the short and long-term deferred revenue and customer advances: 2023 2022 (in thousands) Maintenance, service and training $ 66,458 $ 78,089 Customer advances, undelivered elements and other 35,731 59,147 Extended warranty 34,897 56,180 Total deferred revenue and customer advances $ 137,086 $ 193,416 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: Amount (in thousands) Balance at December 31, 2020 $ 16,633 Accruals for warranties issued during the period 35,727 Accruals related to pre-existing warranties ( 6,846 ) Settlements made during the period ( 20,937 ) Balance at December 31, 2021 24,577 Accruals for warranties issued during the period 21,851 Accruals related to pre-existing warranties ( 5,618 ) Settlements made during the period ( 26,629 ) Balance at December 31, 2022 14,181 Accruals for warranties issued during the period 21,644 Accruals related to pre-existing warranties ( 1,576 ) Settlements made during the period ( 18,551 ) Balance at December 31, 2023 $ 15,698 When Teradyne receives revenue for extended warranties, beyond one year, it is 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: Amount (in thousands) Balance at December 31, 2020 $ 51,929 Deferral of new extended warranty revenue 43,597 Recognition of extended warranty deferred revenue ( 31,358 ) Balance at December 31, 2021 64,168 Deferral of new extended warranty revenue 33,686 Recognition of extended warranty deferred revenue ( 41,674 ) Balance at December 31, 2022 56,180 Deferral of new extended warranty revenue 14,330 Recognition of extended warranty deferred revenue ( 35,613 ) Balance at December 31, 2023 $ 34,897 Accounts Receivable and Allowance for Credit Losses Trade accounts receivable are recorded at the invoiced amount and do not bear interest. Teradyne maintains allowances for estimated losses resulting from the inability of its customers to make required payments. Estimated allowances for credit losses are reviewed periodically taking into account the customer’s recent payment history, the customer’s current financial statements and other information regarding the customer’s creditworthiness. Account balances are written off against the allowance when it is determined the receivable will not be recovered. Teradyne sells certain trade accounts receivables on a non-recourse basis to third-party financial institutions pursuant to factoring agreements. Teradyne accounts for these transactions as sales of receivables and presents cash proceeds as a cash provided by operating activities in the consolidated statements of cash flows. Total trade accounts receivable sold under the factoring agreements were $ 243.5 million and $ 93.9 million during 2023 and 2022 , respectively. Factoring fees for the sales of receivables are recorded in interest expense and are not material. Inventories Inventories are stated at the lower of cost (first-in, first-out basis) or net realizable value. On a quarterly basis, Teradyne uses consistent methodologies to evaluate all inventories for net realizable value. Teradyne records a provision for both excess and obsolete inventory when such write-downs or write-offs are identified through the quarterly review process. The inventory valuation is based upon assumptions about future demand, product mix and possible alternative uses. Investments Teradyne accounts for its investments in debt and equity securities in accordance with the provisions of ASC 320-10, “ Investments—Debt and Equity Securities .” ASC 320-10 requires that certain debt and equity securities be classified into one of three categories; trading, available-for-sale or held-to-maturity securities. On a quarterly basis, Teradyne reviews its investments to identify and evaluate those that have an indication of a potential other-than-temporary impairment. Factors considered in determining whether a loss is other-than-temporary include: • The length of time and the extent to which the market value has been less than cost; • The financial condition and near-term prospects of the issuer; and • The intent and ability to retain the investment in the issuer for a period of time sufficient to allow for any anticipated recovery in market value. Teradyne uses the market and income approach techniques to value its financial instruments and there were no changes in valuation techniques during the twelve months ended December 31, 2023 and 2022. Teradyne measures its debt and equity investments at fair value, in accordance with ASC 820-10, “ Fair Value Measurements and Disclosures. ” ASC 820-10 defines fair value as the price that would be received from the sale of an asset or paid to transfer a liability in an orderly transaction between market participants and requires that assets and liabilities carried at fair value be classified and disclosed in one of the following three categories: Level 1: Quoted prices in active markets for identical assets as of the reporting date; Level 2: Inputs other than Level 1, that are observable either directly or indirectly as of the reporting date. For example, a common approach for valuing fixed income securities is the use of matrix pricing. Matrix pricing is a mathematical technique used to value securities by relying on the securities’ relationship to other benchmark quoted prices, and is considered a Level 2 input; or Level 3: Unobservable inputs that are not supported by market data. Unobservable inputs are developed based on the best information available, which might include Teradyne’s own data. Teradyne’s debt investments are classified as Level 2, and equity investments are classified as Level 1. Acquisition-related contingent consideration is classified as Level 3. Teradyne determines the fair value of acquisition-related contingent consideration using a Monte Carlo simulation model. Assumptions utilized in the model include forecasted revenues, revenue volatility, earnings before interest and taxes, and discount rate. Financial Assets and Financial Liabilities Teradyne records changes in fair value of equity securities directly in earnings and unrealized gains and losses in other (income) expense, net, in accordance with ASU 2016-01, “ Financial Instruments—Overall (Subtopic 825-10): Recognition and Measurement of Financial Assets and Financial Liabilities .” Prepayments Prepayments consist of the following: 2023 (1) 2022 (in thousands) Contract manufacturer and supplier prepayments $ 502,257 $ 491,105 Prepaid maintenance and other services 17,592 14,545 Prepaid taxes 16,083 18,625 Other prepayments 13,038 8,687 Total prepayments $ 548,970 $ 532,962 (1) Excludes $ 5.3 million of contract manufacturer and supplier prepayments, classified as assets held for sale. See Note E: “Assets held for sale” for additional information. Retirement and Postretirement Plans Teradyne recognizes net actuarial gains and losses and the change in the fair value of the plan assets in its operating results in the year in which they occur or upon any interim remeasurement of the plans. Teradyne calculates the expected return on plan assets using the fair value of the plan assets. Actuarial gains and losses are generally measured annually as of December 31 and, accordingly, recorded during the fourth quarter of each year or upon any interim remeasurement of the plans. Teradyne reports net periodic pension cost and net periodic postretirement benefit costs in accordance with ASU 2017-07, “ Compensation—Retirement Benefits (Topic 715): Improving the Presentation of Net Periodic Pension Cost and Net Periodic Postretirement Benefit Cost .” The service cost component of net benefit costs is reported in the same line item in the consolidated statement of operations as other employee compensation costs. The non-service components of net benefit costs such as interest cost, expected return on assets, amortization of prior service cost, and actuarial gains or losses, are reported within other (income) expense, net. Goodwill, Intangible and Long-Lived Assets Teradyne accounts for goodwill and intangible assets in accordance with ASC 350-10, “ Intangibles-Goodwill and Other. ” Intangible assets are amortized over their estimated useful economic life and are carried at cost less accumulated amortization. Goodwill is assessed for impairment at least annually in the fourth quarter, as of December 31, on a reporting unit basis, or more frequently when events and circumstances occur indicating that the recorded goodwill may be impaired. In accordance with ASC 350-10, Teradyne has the option to perform a qualitative assessment to determine whether it is more likely than not that the fair value of a reporting unit is less than its carrying amount. If Teradyne determines this is the case, Teradyne is required to perform a quantitative goodwill impairment test to identify potential goodwill impairment and measure the amount of goodwill impairment loss to be recognized. If Teradyne determines that it is more likely than not that the fair value of the reporting unit is greater than its carrying amounts, a quantitative goodwill impairment test is not required. In accordance with ASC 360-10, “ Impairment or Disposal of Long-Lived Assets, ” Teradyne reviews long-lived assets for impairment whenever events or changes in business circumstances indicate that the carrying amount of the assets may not be fully recoverable or that the useful lives of these assets are no longer appropriate. Each impairment test is based on a comparison of the estimated undiscounted cash flows to the recorded value of the asset. If impairment is indicated, the asset is written down to its estimated fair value based on a discounted cash flows analysis. The cash flows estimates used to determine the impairment, if any, contain management’s best estimates using appropriate assumptions and projections at that time. Business Combination Teradyne recognizes the tangible and intangible assets acquired and liabilities assumed based on their estimated fair values at the date of acquisition. The fair value of identifiable intangible assets is based on detailed cash flows valuations that use information and assumptions provided by management. Teradyne estimates the fair value of contingent consideration at the time of the acquisition using all pertinent information known to us at the time to assess the probability of payment of contingent amounts or through the use of a Monte Carlo simulation model. Teradyne allocates any excess purchase price over the fair value of the net tangible and intangible assets acquired and liabilities assumed to goodwill. The assumptions used in the valuations for our acquisitions may differ materially from actual results depending on performance of the acquired businesses and other factors. While Teradyne believes the assumptions used were appropriate, different assumptions in the valuation of assets acquired and liabilities assumed could have a material impact on the timing and extent of impact on our statements of operations. Goodwill is assigned to reporting units as of the date of the related acquisition. Property, Plant and Equipment Property, plant and equipment are stated at cost and depreciated over the estimated useful lives of the assets. Leasehold improvements and major renewals are capitalized and included in property, plant and equipment accounts, while expenditures for maintenance and repairs and minor renewals are charged to expense. When assets are retired, the assets and related accumulated depreciation are removed from the accounts and any resulting gain or loss is reflected in the consolidated statements of operations. Teradyne provides for depreciation of its assets principally on the straight-line method with the cost of the assets being charged to expense over their useful lives as follows: Buildings 40 years Building improvements 5 to 10 years Leasehold improvements Lesser of lease term or 10 years Furniture and fixtures 10 years Test systems manufactured internally 6 years Machinery, equipment and software 3 to 5 years Test systems manufactured internally are used by Teradyne for customer evaluations and manufacturing and support of its customers. Teradyne depreciates the test systems manufactured internally over a six-year life to cost of revenues, engineering and development, and selling and administrative expenses. Teradyne often sells internally manufactured test equipment to customers. Upon the sale of an internally manufactured test system, the net book value of the system is transferred to inventory and expensed as cost of revenues. The net book value of internally manufactured test systems sold in the years ended December 31, 2023, 2022, and 2021 was $ 2.8 million, $ 6.6 million, and $ 16.6 million, respectively. Convertible Debt Teradyne adopted Accounting Standards Update (“ASU”) ASU 2020-06 – “Debt—Debt with Conversion and Other Options and Derivatives and Hedging—Contracts in Entity’s Own Equity,” on January 1, 2022 using the modified retrospective method of adoption. As a result of adoption, Teradyne recorded an increase of $ 1.4 million to current debt for unsettled shares, an increase of $ 1.8 million to deferred tax assets, an increase of $ 6.6 million to long-term debt for unamortized debt discount, and an increase to retained earnings of $ 94.6 million for the reclassification of the equity component. Mezzanine equity representing unsettled shares value was reduced to zero and additional paid-in capital was reduced by $ 100.8 million. In accordance with ASU 2020-06, Teradyne accounts for a convertible debt instrument as a single liability measured at its amortized cost, as long as no other features require bifurcation and recognition as derivatives. Unsettled shares are recorded in current debt, and there is no recognition of a debt discount, which was previously amortized to interest expense. Settled shares reduce the outstanding debt balance in an amount equal to the cash paid, but do not result in any gain or loss on extinguishment. We use the if-converted method in the diluted EPS calculation for convertible instruments. Leases Under ASC 842, a contract is or contains a lease when Teradyne has the right to control the use of an identified asset. Teradyne determines if an arrangement is a lease at inception of the contract, which is the date on which the terms of the contract are agreed to and the agreement creates enforceable rights and obligations. The commencement date of the lease is the date that the lessor makes an underlying asset available for use by Teradyne. As of December 31, 2023, Teradyne does not have material leases that have not yet commenced. Teradyne determines if the lease is an operating or finance lease at the lease commencement date based upon the terms of the lease and the nature of the asset. The lease term used to calculate the lease liability includes options to extend or terminate the lease when it is reasonably certain that the option will be exercised. The lease liability is measured at the present value of future lease payments, discounted using the discount rate for the lease at the commencement date. As Teradyne is typically unable to determine the implicit rate, Teradyne uses an incremental borrowing rate based on the lease term and economic environment at commencement date. Teradyne initially measures payments based on an index by using the applicable rate at lease commencement. Variable payments that do not depend on an index are not included in the lease liability and are recognized as they are incurred. The right-of-use (“ROU”) asset is initially measured as the amount of lease liability, adjusted for any initial lease costs, prepaid lease payments, and reduced by any lease incentives. Teradyne’s contracts often include non-lease components such as common area maintenance. Teradyne elected the practical expedient to account for the lease and non-lease components as a single lease component. For leases with a term of one year or less, Teradyne has elected not to record the lease asset or liability. The lease payments are recognized in the consolidated statement of earnings on a straight-line basis over the lease term. Teradyne includes lease costs within cost of revenues and operating expenses. See Note I: “Leases.” Engineering and Development Costs Teradyne’s products are highly technical in nature and require a large and continuing engineering and development effort. Software development costs incurred prior to the establishment of technological feasibility are charged to expense. Software development costs incurred subsequent to the establishment of technological feasibility are capitalized until the product is available for release to customers. To date, the period between achieving technological feasibility and general availability of the product has been short and software development costs eligible for capitalization have not been material. Engineering and development costs are expensed as incurred and consist primarily of salaries, contractor fees including non-recurring engineering charges related to product design, allocated facility costs, depreciation, and tooling costs. Stock Compensation Plans and Employee Stock Purchase Plan Stock-based compensation expense is based on the grant-date fair value estimated in accordance with the provisions of ASC 718-10, “ Compensation-Stock Compensation .” Teradyne elects to account for forfeitures by applying an estimated forfeiture rate and recognizes compensation costs only for those stock-based compensation awards expected to vest. Under its stock compensation plans, Teradyne has granted stock options, restricted stock units and performance-based restricted stock units, and employees are eligible to purchase Teradyne’s common stock through its Employee Stock Purchase Plan (“ESPP”). Excess tax benefits or tax deficiencies are recognized as a discrete tax benefit or discrete tax expense to the current income tax provision in Teradyne’s consolidated statements of operations, all excess tax benefits related to share-based payments are reported as cash flows from operating activities, and all cash payments made to taxing authorities on the employees’ behalf for withheld shares are presented as financing activities on the statement of cash flows. Income Taxes Deferred tax assets and liabilities are determined based on differences between financial reporting and tax basis of assets and liabilities and are measured using the enacted tax rates and laws that will be in effect when the differences are expected to reverse. The measurement of deferred tax assets is reduced by a valuation allowance if it is more likely than not that some or all of the deferred tax assets will not be realized. Teradyne performed the required assessment of positive and negative evidence regarding the realization of the net deferred tax assets in accordance with ASC 740, “Accounting for Income Taxes.” This assessment included the evaluation of scheduled reversals of deferred tax liabilities, estimates of projected future taxable income and tax-planning strategies. Although realization is not assured, based on its assessment, Teradyne concluded that it is more likely than not that such assets, net of the existing valuation allowance, will be realized. Advertising Costs Teradyne expenses all advertising costs as incurred. Advertising costs were $ 15.5 million, $ 17.3 million and $ 13.4 million in 2023, 2022 and 2021 , respectively. Translation of Non-U.S. Currencies The functional currency for all non-U.S. subsidiaries is the U.S. dollar, except for Universal Robots, MiR and Lemsys for which the local currency is its functional currency. All foreign currency denominated monetary assets and liabilities are remeasured on a monthly basis into the functional currency using exchange rates in effect at the end of the period. All foreign currency denominated non-monetary assets and liabilities are remeasured into the functional currency using historical exchange rates. Net foreign exchange gains and losses resulting from remeasurement are included in other (income) expense, net. For Universal Robots, MiR and Lemsys, assets and liabilities are translated into U.S. dollars using exchange rates in effect at the end of the period. Revenues and expense amounts are translated using an average of exchange rates in effect during the period. Translation adjustments are recorded within accumulated other comprehensive income (loss) on the balance sheet. Net foreign exchange gains and losses resulting from remeasurement are included in other (income) expense, net. For the years ended December 31, 2023, 2022 and 2021 , losses (gains) from the remeasurement of the monetary assets and liabilities denominated in foreign currencies were $ 10.9 million, $ 10.8 million, and $( 2.1 ) million, respectively. These amounts do not reflect the corresponding (gains) losses from foreign exchange contracts. See Note H: “Financial Instruments” regarding foreign exchange contracts. Net Income per Common Share Basic net income per common share is calculated by dividing net income by the weighted average number of common shares outstanding during the period. Except where the result would be anti-dilutive, diluted net income per common share is calculated by dividing net income by the sum of the weighted average number of common shares plus common stock equivalents, if applicable. With respect to its convertible debt issued in 2016, Teradyne is required to settle the principal of the convertible debt in cash; accordingly, the principal amount is excluded from the determination of diluted earnings per share. As a result, Teradyne is accounting for the conversion spread using the treasury stock method. Comprehensive Income Comprehensive income includes net income, unrealized pension and postretirement prior service costs and benefits, unrealized gains and losses on investments in debt marketable securities, unrealized gains and losses on cash flow hedge and foreign currency translation adjustment.

Recently Issued Accounting Pron

Recently Issued Accounting Pronouncements	12 Months Ended
	Dec. 31, 2023
Accounting Changes and Error Corrections [Abstract]
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 us 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, we 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 Teradyne’s 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. Teradyne is currently evaluating the impact of this new standard.

Revenue

Revenue	12 Months Ended
	Dec. 31, 2023
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 Robotics System-on-a-chip Memory System Universal Robots Mobile Industrial Robots Wireless Corporate Total (in thousands) For the Year Ended December 31, 2023 (1) Timing of Revenue Recognition Point in Time $ 1,141,882 $ 356,417 $ 268,379 $ 296,252 $ 66,986 $ 129,399 $ — $ 2,259,315 Over Time 290,739 29,598 69,818 7,540 4,405 14,883 — 416,983 Total $ 1,432,621 $ 386,015 $ 338,197 $ 303,792 $ 71,391 $ 144,282 $ — $ 2,676,298 Geographical Market Asia Pacific $ 1,214,322 $ 366,151 $ 153,387 $ 63,312 $ 10,424 $ 85,415 $ — $ 1,893,011 Americas 117,728 11,367 151,579 111,761 36,191 50,770 — 479,396 Europe, Middle East and Africa 100,571 8,497 33,231 128,719 24,776 8,097 — 303,891 Total $ 1,432,621 $ 386,015 $ 338,197 $ 303,792 $ 71,391 $ 144,282 $ — $ 2,676,298 For the Year Ended December 31, 2022 (1) Timing of Revenue Recognition Point in Time $ 1,445,238 $ 344,693 $ 402,074 $ 317,514 $ 73,812 $ 189,040 $ 251 $ 2,772,622 Over Time 261,646 29,013 67,272 8,218 3,594 12,680 — 382,423 Total $ 1,706,884 $ 373,706 $ 469,346 $ 325,732 $ 77,406 $ 201,720 $ 251 $ 3,155,045 Geographical Market Asia Pacific $ 1,514,964 $ 360,176 $ 294,350 $ 73,930 $ 15,724 $ 140,767 $ — $ 2,399,911 Americas 122,575 11,987 146,040 112,203 35,213 47,350 251 475,619 Europe, Middle East and Africa 69,345 1,543 28,956 139,599 26,469 13,603 — 279,515 Total $ 1,706,884 $ 373,706 $ 469,346 $ 325,732 $ 77,406 $ 201,720 $ 251 $ 3,155,045 For the Year Ended December 31, 2021 (1) Timing of Revenue Recognition Point in Time $ 1,989,979 $ 365,441 $ 409,383 $ 305,512 $ 60,884 $ 204,247 $ — $ 3,335,446 Over Time 256,751 30,171 58,356 5,670 3,839 12,648 — 367,435 Total $ 2,246,730 $ 395,612 $ 467,739 $ 311,182 $ 64,723 $ 216,895 $ — $ 3,702,881 Geographical Market Asia Pacific $ 2,076,647 $ 381,444 $ 306,812 $ 81,456 $ 12,919 $ 172,103 $ — $ 3,031,381 Americas 102,702 10,665 135,230 94,897 26,069 36,173 — 405,736 Europe, Middle East and Africa 67,381 3,503 25,697 134,829 25,735 8,619 — 265,764 Total $ 2,246,730 $ 395,612 $ 467,739 $ 311,182 $ 64,723 $ 216,895 $ — $ 3,702,881 (1) Includes $ 5.2 m illion, $ 8.2 million and $ 13.2 million in 2023, 2022 and 2021, respectively, for leases of Teradyne’s systems recognized outside of ASC 606: “Revenue from Contracts with Customers.” Contract Balances For the years ended December 31, 2023, 2022 and 2021 , Teradyne recognized $ 108.1 million, $ 112.4 million and $ 102.5 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 December 31, 2023 , Teradyne had $ 1,124.6 million of unsatisfied performance obligations. Teradyne expects to recognize 90 % of the remaining performance obligation in the next 12 months , 9 % in 1 - 3 year s, and 1 % thereafter .

Assets Held for Sale

Assets Held for Sale	12 Months Ended
	Dec. 31, 2023
Discontinued Operations and Disposal Groups [Abstract]
Assets Held for Sale	E. ASSETS HELD FOR SALE On November 7, 2023, Teradyne entered into a definitive agreement to sell Teradyne’s Device Interface Solutions ("DIS") business, a component of the Semiconductor Test segment, to Technoprobe S.p.A. for $ 85.0 million in cash. As a result, the related assets and liabilities met the criteria and were classified as held-for-sale in Teradyne’s consolidated balance sheet as of December 31, 2023. The transaction, which does not qualify as a strategic shift required for discontinued operations treatment, is expected to close in the first half of 2024. Assets held-for-sale comprise of the following as of December 31, 2023: December 31, 2023 (in thousands) 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

Inventories

Inventories	12 Months Ended
	Dec. 31, 2023
Inventory Disclosure [Abstract]
Inventories	F. INVENTORIES Inventories, net consisted of the following at December 31, 2023 and 2022: 2023 (1) 2022 (in thousands) Raw material $ 258,422 $ 256,065 Work-in-process 26,851 37,982 Finished goods 24,701 30,972 $ 309,974 $ 325,019 (1) Excludes $ 18.0 million of primarily work-in-process inventories, net classified as assets held for sale. See Note E: “Assets held for sale” for additional information.

Property, Plant and Equipment

Property, Plant and Equipment	12 Months Ended
	Dec. 31, 2023
Property, Plant and Equipment [Abstract]
Property, Plant and Equipment	G. PROPERTY, PLANT AND EQUIPMENT Property, plant and equipment, net consisted of the following at December 31, 2023 and 2022: 2023 (1) 2022 (in thousands) Land $ 19,487 $ 18,481 Buildings 127,705 128,991 Machinery, equipment and software 1,047,235 1,059,880 Furniture and fixtures 28,093 29,929 Leasehold improvements 66,777 64,631 Construction in progress 54,799 22,470 1,344,096 1,324,382 Less: accumulated depreciation 898,604 905,699 $ 445,492 $ 418,683 (1) Excludes $ 9.0 million of property, plant and equipment, net classified as assets held for sale. See Note E: “Assets held for sale” for additional information. Depreciation of property, plant and equipment for the years ended December 31, 2023, 2022, and 2021 was $ 92.1 million, $ 90.8 million, and $ 91.1 million, respectively. As of December 31, 2023 and 2022 , the gross book value included in machinery and equipment for internally manufactured test systems being leased by customers was $ 5.1 million and $ 5.8 million, respectively. As of December 31, 2023 and 2022 , the accumulated depreciation on these test systems was $ 4.9 million and $ 5.6 million, respectively.

Financial Instruments

Financial Instruments	12 Months Ended
	Dec. 31, 2023
Fair Value Disclosures [Abstract]
Financial Instruments	H. FINANCIAL INSTRUMENTS Cash Equivalents Teradyne considers all highly liquid investments with maturities of three months 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. Contingent consideration is classified as Level 3. 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 years ended December 31, 2023 and 2022, there were no transfers in or out of Level 1, Level 2, or Level 3 financial instruments. Realized gains recorded in 2023, 2022, and 2021 were $ 0.6 million, $ 0.8 million, and $ 3.1 million, respectively. Realized losses recorded in 2023 and 2022 were $ 0.3 million and $ 1.0 million, respectively. No realized losses were recorded in 2021. Realized gains and losses are included in other (income) expense, net. Unrealized gains on equity securities recorded during the years ended December 31, 2023, 2022 and 2021 were $ 8.9 million, $ 1.9 million and $ 5.1 million, respectively. Unrealized losses on equity securities recorded during the years ended December 31, 2023, 2022, and 2021 were $ 1.7 million, $ 11.6 million and $ 1.8 million, respectively. Unrealized gains and losses on equity securities are included in other (income) expense, net. Unrealized gains and losses on available-for-sale debt securities are included in accumulated other comprehensive income (loss) on the balance sheet. The cost of securities sold is based on average cost. The following table sets forth by fair value hierarchy Teradyne’s financial assets and liabilities that were measured at fair value on a recurring basis as of December 31, 2023 and 2022 : 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 Commercial paper — 1,667 — 1,667 Debt mutual funds 8,773 — — 8,773 U.S. government agency securities — 4,892 — 4,892 Certificates of deposit and time deposits — 21,772 — 21,772 Non-U.S. government securities — 810 — 810 Equity securities: Mutual funds 47,132 — — 47,132 Total $ 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 December 31, 2022 Quoted Prices Significant Significant Total (in thousands) Assets Cash $ 632,417 $ — $ — $ 632,417 Cash equivalents 161,767 60,589 — 222,356 Available for sale securities: Corporate debt securities — 50,856 — 50,856 U.S. Treasury securities — 39,649 — 39,649 Commercial paper — 7,159 — 7,159 Debt mutual funds 6,580 — — 6,580 U.S. government agency securities — 6,352 — 6,352 Certificates of deposit and time deposits — 1,740 — 1,740 Non-U.S. government securities — 535 — 535 Equity securities: Mutual funds 37,518 — — 37,518 Total $ 838,282 $ 166,880 $ — $ 1,005,162 Derivative assets — 86 — 86 Total $ 838,282 $ 166,966 $ — $ 1,005,248 Liabilities Derivative liabilities — 4,215 — 4,215 Total $ — $ 4,215 $ — $ 4,215 Reported as follows: (Level 1) (Level 2) (Level 3) Total (in thousands) Assets Cash and cash equivalents $ 794,184 $ 60,589 $ — $ 854,773 Marketable securities — 39,612 — 39,612 Long-term marketable securities 44,098 66,679 — 110,777 Other current assets — 86 — 86 Total $ 838,282 $ 166,966 $ — $ 1,005,248 Liabilities Other current liabilities $ — $ 4,215 $ — $ 4,215 Total $ — $ 4,215 $ — $ 4,215 The carrying amounts and fair values of Teradyne’s financial instruments at December 31, 2023 and 2022 were as follows: December 31, 2023 December 31, 2022 Carrying Value Fair Value Carrying Value Fair Value (in thousands) Assets Cash and cash equivalents $ 757,571 $ 757,571 $ 854,773 $ 854,773 Marketable securities 179,588 179,588 150,389 150,389 Derivative assets 18,746 18,746 86 86 Liabilities Derivative liabilities 2,545 2,545 4,215 4,215 Convertible debt (1) — — 50,115 139,007 (1) The carrying value represents the bifurcated debt component only, while the fair value is based on quoted market prices for the convertible note which includes the equity conversion features. The fair values of accounts receivable, net and accounts payable approximate the carrying amount due to the short-term nature of these instruments. The following tables summarize the composition of available-for-sale marketable securities at December 31, 2023 and 2022: December 31, 2023 Available-for-Sale Cost Unrealized Unrealized Fair Market 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 Market 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 December 31, 2022 Available-for-Sale Cost Unrealized Unrealized Fair Market Fair Market (in thousands) Corporate debt securities $ 57,006 $ 3 $ ( 6,153 ) $ 50,856 $ 50,667 U.S. Treasury securities 44,030 — ( 4,381 ) 39,649 39,649 Commercial paper 7,089 70 — 7,159 — Debt mutual funds 6,997 — ( 417 ) 6,580 3,095 U.S. government agency securities 6,442 — ( 90 ) 6,352 6,352 Certificates of deposit and time deposits 1,740 — — 1,740 — Non-U.S. government securities 535 — — 535 — $ 123,839 $ 73 $ ( 11,041 ) $ 112,871 $ 99,763 Reported as follows: Cost Unrealized Unrealized Fair Market Fair Market (in thousands) Marketable securities $ 39,950 $ 70 $ ( 408 ) $ 39,612 $ 30,713 Long-term marketable securities 83,889 3 ( 10,633 ) $ 73,259 69,050 $ 123,839 $ 73 $ ( 11,041 ) $ 112,871 $ 99,763 As of December 31, 2023, the fair market value of investments with unrealized losses less than one year and greater than one year totaled $ 22.3 million and $ 65.2 million, respectively. As of December 31, 2022, the fair market value of investments with unrealized losses less than one year and greater than one year totaled $ 66.3 million and $ 33.4 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 December 31, 2023 and 2022 were not other than temporary. The contractual maturities of investments in available-for-sale marketable securities held at December 31, 2023 were as follows: Cost Fair Value (in thousands) Due within one year $ 62,385 $ 62,154 Due after 1 year through 5 years 23,703 23,319 Due after 5 years through 10 years 6,049 5,735 Due after 10 years 39,159 32,475 Total $ 131,296 $ 123,683 Contractual maturities of investments in available-for-sale marketable securities held at December 31, 2023 exclude debt mutual funds with the fair market value of $ 8.8 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 December 31, 2023 and 2022, to hedge certain of its local currency balance sheet assets and liabilities, 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 December 31, December 31, 2022 (in millions) Currency Hedged (Buy/Sell) U.S. dollar/Taiwan dollar $ 42.7 $ 29.2 U.S. dollar/Danish krone 36.0 — U.S. dollar/Japanese yen 11.0 37.1 U.S. dollar/Korean won 7.2 6.4 U.S. dollar/British pound sterling 1.5 1.2 Euro/U.S. dollar 25.3 38.4 Singapore dollar/U.S. dollar 16.6 33.5 Philippine peso/U.S. dollar 10.1 2.7 Chinese yuan/U.S. dollar 1.0 2.2 Danish krone/U.S. dollar 0.7 — Total 152.1 150.7 The change in the fair value of the outstanding contracts was a loss of $ 1.8 million and $ 0.9 million, respectively, at December 31, 2023 and 2022. 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. At December 31, 2023 and 2022, 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 December 31, December 31, 2022 (in millions) Currency Hedged (Buy/Sell) U.S. dollar/Japanese yen $ 35.5 $ 61.2 U.S. dollar/Taiwan dollar — 10.9 Japanese yen/U.S. dollar — 23.4 Taiwan dollar/U.S. dollar — 5.5 Total $ 35.5 $ 101.0 The change in the fair value of the outstanding cash flow hedge contracts was a gain of $ 0.6 million at December 31, 2023 and a loss of $ 3.2 million at December 31, 2022. 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 our agreement to acquire 10 % investment in Technoprobe S.p.A we purchased a call option to buy 481.0 million Euros. The expiration date of the option is April 26, 2024 . At December 31, 2023, the fair value of the outstanding contract was $ 17.4 million and an unrealized gain of $ 7.5 million was recorded in other (income) expense, net. T he following table summarizes the fair value of derivative instruments as of December 31, 2023 and 2022: Balance Sheet Location December 31, December 31, (in thousands) Derivatives not designated as hedging instruments: Foreign exchange forward contracts Other current assets $ 733 $ 86 Foreign exchange option contracts Other current assets 17,364 — Foreign exchange forward contracts Other current liabilities ( 2,545 ) ( 990 ) Derivatives designated as hedging instruments: Foreign exchange forward contracts Other current assets 648 — Foreign exchange option contracts Other current liabilities — ( 3,225 ) Total derivatives $ 16,200 $ ( 4,129 ) The following table summarizes the effect of derivative instruments in the statements of operations recognized for the years ended December 31, 2023, 2022, and 2021: Location of (Gains) Losses December 31, December 31, December 31, (in thousands) Derivatives not designated as hedging instruments: Foreign exchange forward contracts (1) Other (income) expense, net $ ( 1,843 ) $ ( 2,482 ) $ 6,488 Foreign exchange option contracts Other (income) expense, net ( 7,464 ) — — Derivatives designated as hedging instruments: Foreign exchange forward and option contracts Revenue ( 3,127 ) ( 251 ) — Total derivatives $ ( 12,434 ) $ ( 2,733 ) $ 6,488 (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 years ended December 31, 2023, 2022 and 2021 , net losses (gains) from remeasurement of monetary assets and liabilities denominated in foreign currencies were $ 10.9 million, $ 10.8 million, and $( 2.1 ) million, respectively. See Note J: “Debt” regarding derivatives related to the convertible senior notes. Concentration of Credit Risk Financial instruments which potentially subject Teradyne to concentrations of credit risk consist principally of cash equivalents, marketable securities, forward currency contracts and accounts receivable. Teradyne’s cash equivalents consist primarily of money market funds invested in U.S. Treasuries and government agencies. Teradyne’s fixed income available-for-sale marketable securities have a minimum rating of AA by one or more of the major credit rating agencies. Teradyne places foreign currency forward contracts with high credit-quality financial institutions in order to minimize credit risk exposure. Concentrations of credit risk with respect to accounts receivable are limited due to the large number of geographically dispersed customers. Teradyne performs ongoing credit evaluations of its customers’ financial condition and from time to time may require customers to provide a letter of credit from a bank to secure accounts receivable. As of December 31, 2023, one customer of our Semiconductor Test segment, Texas Instruments Inc., accounted for 18 % of our accounts receivable balance. There were no customers who accounted for more than 10 % of our accounts receivable balance as of December 31, 2022 .

Leases

Leases	12 Months Ended
	Dec. 31, 2023
Leases, Operating [Abstract]
Leases	I. LEASES Teradyne has facility and auto leases, which are accounted for as operating leases. Teradyne’s facility leases are primarily used for administrative functions, research and development, manufacturing, and storage and distribution. Remaining lease terms range from less than one year to twelve years. For the years ended December 31, 2023, 2022 and 2021 , total lease expense was $ 42.7 million, $ 40.1 million, and $ 39.2 million respectively, and included $ 15.5 million, $ 14.1 million, and $ 12.6 million, respectively, of variable lease costs and $ 1.3 million, $ 2.0 million, and $ 1.8 million, respectively, of costs related to short-term leases, which are not recorded on the consolidated balance sheets. At December 31, 2023 , the weighted average remaining lease term and weighted average discount rate for operating leases was 6.3 years and 5.2 %, respectively. At December 31, 2022 , the weighted average remaining lease term and weighted average discount rate for operating leases was 5.9 years and 4.7 %, respectively. Supplemental cash flows information related to leases was as follows: For the Years Ended December 31, December 31, December 31, (in thousands) Cash paid for amounts included in the measurement of lease $ 26,059 $ 20,775 $ 24,593 Right-of-use assets obtained in exchange for new lease obligations 17,987 26,149 34,246 Maturities of lease liabilities as of December 31, 2023 were as follows: Operating Lease (1) (in thousands) 2024 $ 21,045 2025 18,755 2026 15,074 2027 11,733 2028 7,622 Thereafter 23,906 Total lease payments 98,135 Less imputed interest ( 15,521 ) Total lease liabilities $ 82,614 (1) Excludes $ 2.5 million of lease liabilities classified as liabilities held for sale. See Note E: “Assets held for sale” for additional information.

Debt

Debt	12 Months Ended
	Dec. 31, 2023
Debt Disclosure [Abstract]
Debt	J. 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 . Substantially all of the Notes were converted as of December 15, 2023. During 2023, twenty three debt holders elected to convert $ 50.2 million of debt principal. The conversion of the debt was settled in cash for principal amount and in shares for the excess of conversion value over principal amount. The 1.1 million shares issued to the debt holders were received from exercising the convertible notes hedge call options. 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 our shareholders equity. The Warrant Transactions, which expire between March 18, 2024 and July 10, 2024 , currently cover, subject to customary anti-dilution adjustments, approximately 14.7 million shares of common stock. As of December 31, 2023, the strike price of the warrants was approximately $ 39.40 per share. The strike price is subject to adjustment under certain circumstances. The Warrant Transactions could result 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 net cost of the Note Hedge Transactions, after being partially offset by the proceeds from the sale of the warrants, was approximately $ 33.0 million. In connection with establishing their initial hedge of these convertible note hedge and warrant transactions, the Option Counterparties have entered into various derivative transactions with respect to Teradyne’s common stock and/or purchased shares of Teradyne’s common stock or other securities, including the Notes, concurrent with, or shortly after, the pricing of the Notes. In addition, the Option Counterparties may modify their hedge positions by entering into or unwinding various derivative transactions with respect to Teradyne’s common stock or by selling Teradyne’s common stock or other securities, including the Notes, in secondary market transactions (and may do so during any observation period related to the conversion of the Notes). These activities could adversely affect the value of Teradyne’s common stock and the Notes. Originally, Teradyne allocated $ 100.8 million of the $ 460.0 million principal amount of the Notes to the equity component, which represented a discount to the debt and was amortized to interest expense using the effective interest method through December 2023. Effective January 1, 2022, Teradyne adopted ASC 2020-06 using the modified retrospective method of transition and accounts for the debt as a single liability measured at its amortized cost. As a result of the adoption, Teradyne recorded an increase of $ 1.4 million to current debt for unsettled shares, an increase of $ 1.8 million to deferred tax assets, an increase of $ 6.6 million to long-term debt for unamortized debt discount, and an increase to retained earnings of $ 94.6 million for the reclassification of the equity component. Mezzanine equity representing unsettled shares value was reduced to zero and additional paid-in capital was reduced by $ 100.8 million. The below tables represent the key components of Teradyne’s convertible senior notes: For the Years Ended December 31, December 31, (in thousands) Debt principal $ — $ 50,228 Unamortized debt issuance fees — 113 Net carrying amount of convertible debt $ — $ 50,115 For the Years Ended December 31, December 31, (in thousands) Contractual interest expense on the coupon $ 312 $ 732 Amortization of the issuance fees recognized as interest expense 113 209 Total interest expense on the convertible debt $ 425 $ 941 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 provides 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 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. 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 as of 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. As of February 22, 2024 , the Credit Agreement was undrawn and Teradyne was in compliance with all covenants under the Credit Agreement.

Accumulated Other Comprehensive

Accumulated Other Comprehensive Income (Loss)	12 Months Ended
	Dec. 31, 2023
Equity [Abstract]
Accumulated Other Comprehensive Income (Loss)	K. ACCUMULATED OTHER COMPREHENSIVE INCOME (LOSS) Changes in accumulated other comprehensive income (loss), which is presented net of tax, consist of the following: Foreign Unrealized Unrealized (Losses) Gains on Retirement Total (in thousands) Balance at December 31, 2021, net of tax of $ 0 , $ 1,055 , $ 0 , 1,128 ), respectively $ ( 10,818 ) $ 3,704 $ — $ 1,166 $ ( 5,948 ) Other comprehensive loss before reclassifications, net of tax of 0 , $( 3,388 ), $( 708 ), $ 0 , respectively ( 29,031 ) ( 12,666 ) ( 2,517 ) — ( 44,214 ) Amounts reclassified from accumulated other comprehensive 0 , $ 25 , $ 0 , $( 2 ), respectively — 301 — ( 7 ) 294 Net current period other comprehensive loss, net of tax of $ 0 , 3,363 ), $( 708 ), $( 2 ), respectively ( 29,031 ) ( 12,365 ) ( 2,517 ) ( 7 ) ( 43,920 ) 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 gain before reclassifications, net of tax of 0 , $ 568 , $ 1,537 , $ 0 , respectively 17,407 2,423 5,464 — 25,294 Amounts reclassified from accumulated other comprehensive 0 , $ 12 , $( 686 ), $( 2 ), — 44 ( 2,441 ) ( 7 ) ( 2,404 ) Net current period other comprehensive gain (loss), net of tax 0 $ 580 , $ 851 , $( 2 ), respectively 17,407 2,467 3,023 ( 7 ) 22,890 Balance at December 31, 2023, net of tax of $ 0 , $( 1,728 ), $ 143 , 1,132 ), respectively $ ( 22,442 ) $ ( 6,194 ) $ 506 $ 1,152 $ ( 26,978 ) Reclassifications out of accumulated other comprehensive income (loss) to the statements of operations for the years ended December 31, 2023, 2022, and 2021, were as follows: Details about Accumulate Other Comprehensive Income (Loss) Components For the years ended Affected Line Item December 31, December 31, December 31, (in thousands) Available-for-sale marketable securities Unrealized (losses) gains, net of tax of $( 12 ), $( 25 ), $ 277 , $ ( 44 ) $ ( 301 ) $ 995 Other (income) expense, net Cash flow hedges: Unrealized gains, net of tax of $ 686 , $ 0 , $ 0 , respectively 2,441 — — Revenue Defined benefit pension and postretirement plans: Amortization of prior service benefit, net of tax of $ 2 , $ 2 , $ 2 , 7 7 7 (a) Total reclassifications, net of tax of $ 676 , $( 23 ), $ 279 , respectively $ 2,404 $ ( 294 ) $ 1,002 Net income (a) The amortization of prior service credit is included in the computation of net periodic pension cost and postretirement benefit; see Note P: “Retirement Plans.”

Goodwill and Intangible Assets

Goodwill and Intangible Assets	12 Months Ended
	Dec. 31, 2023
Goodwill and Intangible Assets Disclosure [Abstract]
Goodwill and Intangible Assets	L. GOODWILL AND 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. Goodwill is considered to be impaired when the net book value of a reporting unit exceeds its estimated fair value. Teradyne has the option to perform a qualitative assessment to determine whether it is more likely than not that the fair value of a reporting unit is less than its carrying amount. If Teradyne determines this is the case, Teradyne is required to perform a quantitative goodwill impairment test to identify potential goodwill impairment and measure the amount of goodwill impairment loss to be recognized. If Teradyne determines that it is more likely than not that the fair value of the reporting unit is greater than its carrying amounts, the quantitative goodwill impairment test is not required. In performing the quantitative goodwill impairment test, Teradyne determines the fair value of a reporting unit using the results derived from an income approach and a market approach, weighting the fair value determined under each approach to determine an estimated fair value for a reporting unit. The income approach is estimated through the discounted cash flows (“DCF”) analysis. Determining fair value requires the exercise of significant judgment, including judgments about appropriate discount rates, perpetual growth rates, and the amount and timing of expected future cash flows. Discount rates are based on a weighted average cost of capital (“WACC”), which represents the average rate a business must pay its providers of debt and equity, plus a risk premium. The WACC used to test goodwill is derived from a group of comparable companies. The cash flows employed in the DCF analysis are derived from internal forecasts and external market forecasts. The market approach estimates the fair value of the reporting unit by utilizing the market comparable method which is based on revenue and earnings multiples from comparable companies. If the estimated fair value of a reporting unit exceeds its carrying amount, goodwill of the reporting unit is not impaired. If the carrying amount of a reporting unit exceeds its estimated fair value, then the goodwill is written down by the amount that carrying value exceeds the fair value of the reporting unit, but not below zero. In the fourth quarter of 2023, Teradyne performed the annual goodwill impairment test, completing a quantitative assessment for the Robotics reporting unit and a qualitative assessment for the Wireless Test and System Test reporting units. There was no impairment as a result of the annual test performed in the fourth quarter of 2023. Key assumptions in the goodwill valuation model are forecasted revenues, discount rate, earnings before interest and taxes, and revenue multiples from comparable companies. A change in any of these key assumptions could result in the reporting unit being impaired in a future period. In the fourth quarter of 2022, Teradyne performed the annual goodwill impairment test, completing a quantitative assessment for the Robotics reporting unit and a qualitative assessment for the Wireless Test and System Test reporting units. There was no impairment as a result of the annual test performed in the fourth quarter of 2022. Key assumptions in the goodwill valuation model are forecasted revenues, discount rate, earnings before interest and taxes, and revenue multiples from comparable companies. The changes in the carrying amount of goodwill by reportable segments for the years ended December 31, 2023 and 2022 are as follows: Robotics Wireless Semiconductor System Total (in thousands) Balance at December 31, 2021: Goodwill $ 405,971 $ 361,819 $ 262,101 $ 158,699 $ 1,188,590 Accumulated impairment losses — ( 353,843 ) ( 260,540 ) ( 148,183 ) ( 762,566 ) 405,971 7,976 1,561 10,516 426,024 Foreign currency translation adjustment ( 22,805 ) — ( 24 ) — ( 22,829 ) Balance at December 31, 2022: Goodwill 383,166 361,819 262,077 158,699 1,165,761 Accumulated impairment losses — ( 353,843 ) ( 260,540 ) ( 148,183 ) ( 762,566 ) 383,166 7,976 1,537 10,516 403,195 Foreign currency translation adjustment 12,297 — 160 — 12,457 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 ) $ 395,463 $ 7,976 $ 1,697 $ 10,516 $ 415,652 Intangible Assets Teradyne reviews long-lived assets for impairment whenever events or changes in business circumstances indicate that the carrying amount of the assets may not be fully recoverable or that the useful lives of these assets are no longer appropriate. There were no events or circumstances indicating that the carrying value of intangible and long-lived assets may not be recoverable in 2023, 2022 and 2021. Amortizable intangible assets consist of the following and are included in intangible assets, net on the balance sheets: December 31, 2023 Gross Accumulated Foreign Currency Translation Adjustment Net (in thousands) 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 December 31, 2022 Gross Accumulated Foreign Currency Translation Adjustment Net (in thousands) Developed technology $ 270,967 $ ( 234,208 ) $ ( 5,935 ) $ 30,824 Customer relationships 57,739 ( 51,186 ) 172 6,725 Tradenames and trademarks 59,387 ( 41,930 ) ( 1,528 ) 15,929 Total intangible assets $ 388,093 $ ( 327,324 ) $ ( 7,291 ) $ 53,478 (1) In 2023 and 2022 , $ 9.3 million and $ 1.6 million, respectively, of amortizable intangible assets became fully amortized and have been eliminated from the gross carrying amount and accumulated amortization. Aggregate intangible assets amortization expense for the years ended December 31, 2023, 2022, and 2021 , was $ 19.0 million, $ 19.3 million, and $ 21.5 million, respectively. Estimated intangible assets amortization expense for each of the five succeeding fiscal years is as follows: Year Amortization Expense (in thousands) 2024 $ 18,983 2025 11,402 2026 2,390 2027 1,173 2028 1,092 Thereafter 364

Commitments and Contingencies

Commitments and Contingencies	12 Months Ended
	Dec. 31, 2023
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	M. COMMITMENTS AND CONTINGENCIES Purchase Commitments As of December 31, 2023 , Teradyne had entered into non-cancelable purchase commitments for certain components and materials. The purchase commitments covered by the agreements aggregate to approximately $ 414.4 million, of which $ 379.1 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. On March 8, 2021, Industrial Automation LLC, sellers of AutoGuide, submitted a demand for arbitration against Teradyne and AutoGuide in Wilmington, Delaware alleging that Teradyne and AutoGuide breached certain provisions of the Membership Interests Purchase Agreement (the “Purchase Agreement”), dated as of October 18, 2019, among Industrial Automation LLC, Teradyne and AutoGuide. The arbitration demand sought full acceleration of the maximum earn-out amount payable under the Purchase Agreement, or $ 106.9 million, for the alleged breach of the earn-out provisions of the Purchase Agreement. On March 25, 2022, the arbitration claim was settled for $ 26.7 million. As a result, Teradyne has no remaining earn-out obligations. 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 December 31, 2023 and 2022 , Teradyne had a product warranty accrual of $ 15.7 million and $ 14.2 million, respectively, included in other accrued liabilities, and revenue deferrals related to extended warranties of $ 34.9 million and $ 56.2 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 December 31, 2023, and 2022 , except for product warranty, Teradyne has not recorded any liabilities for these guarantees and obligations because the amount would be immaterial.

Net Income Per Common Share

Net Income Per Common Share	12 Months Ended
	Dec. 31, 2023
Earnings Per Share [Abstract]
Net Income per Common Share	N. NET INCOME PER COMMON SHARE The following table sets forth the computation of basic and diluted net income per common share: 2023 2022 2021 (in thousands, except per share amounts) Net income for basic and diluted net income per share $ 448,752 $ 715,501 $ 1,014,589 Weighted average common shares-basic 154,310 158,434 164,960 Effect of dilutive potential common shares: Convertible note hedge warrant shares (1) 8,897 8,806 9,956 Incremental shares from assumed conversion of convertible notes (2) 633 1,763 7,435 Restricted stock units 423 657 1,180 Stock options 34 52 86 Employee stock purchase rights 7 22 8 Dilutive potential common shares 9,994 11,300 18,665 Weighted average common shares-diluted 164,304 169,734 183,625 Net income per common share-basic $ 2.91 $ 4.52 $ 6.15 Net income per common share-diluted $ 2.73 $ 4.22 $ 5.53 (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 the assumed conversion of the convertible notes was 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 debt, was divided by the average Teradyne stock price for the period. The computation of diluted net income per common share for 2023 excludes the effect of the potential exercise of stock options to purchase approximately 0.1 million shares and restricted stock units to purchase approximately 0.1 million shares because the effect would have been anti-dilutive. The computation of diluted net income per common share for 2022 excludes the effect of the potential exercise of stock options to purchase approximately 0.1 million shares and restricted stock units to purchase approximately 0.4 million shares because the effect would have been anti-dilutive.

Restructuring and Other

Restructuring and Other	12 Months Ended
	Dec. 31, 2023
Restructuring and Related Activities [Abstract]
Restructuring and Other	O. RESTRUCTURING AND OTHER During the year ended December 31, 2023, Teradyne recorded $ 14.7 million of severance charges related to headcount reductions of 215 people primarily in Semiconductor Test and Robotics, which included charges related to a voluntary early retirement program for employees meeting certain conditions, a $ 3.1 million of acquisition and divestiture expenses related to Technoprobe transaction, a $ 1.5 million contract termination charge, and a charge of $ 1.1 million for an increase in environmental liability. During the year ended December 31, 2022, Teradyne recorded a charge of $ 14.7 million related to the arbitration claim filed against Teradyne and AutoGuide related to an earn-out dispute, which was settled on March 25, 2022 for $ 26.7 million, $ 2.9 million of severance charges primarily in Robotics, and a charge of $ 2.7 million for an increase in environmental and legal liabilities, partially offset by a $ 3.4 million gain on sale of asset. During the year ended December 31, 2021, Teradyne recorded a charge of $ 12.0 million related to the arbitration claim filed against Teradyne and AutoGuide related to an earn-out dispute, $ 1.5 million of severance charges primarily in Robotics, $ 0.5 million of acquisition related compensation and expenses, and $ 2.5 million for other expenses, offset by a $ 7.2 million gain for the decrease in the fair value of the AutoGuide contingent consideration liability.

Retirement Plans

Retirement Plans	12 Months Ended
	Dec. 31, 2023
Retirement Benefits [Abstract]
Retirement Plans	P. 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 of 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 the plans in accordance with local laws and to the extent that such contributions are tax deductible. The assets of these plans 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. In 2023, Teradyne’s projected benefit obligations increased primarily due to actuarial losses of approximately $ 6.0 million across all pension plans from increases in discount rates, and approximately $ 1.0 million of losses from foreign exchange effects for foreign plans. In 2022, Teradyne’s projected benefit obligations decreased primarily due to actuarial gains of approximately $ 59.1 million across all pension plans from increases in discount rates, and approximately $ 3.1 million gain from foreign exchange effects for foreign plans. The December 31 balances of these defined benefit pension plans assets and obligations are shown below: 2023 2022 United States Foreign United States Foreign (in thousands) Assets and Obligations Change in benefit obligation: Projected benefit obligation: Beginning of year $ 143,814 $ 29,935 $ 192,472 $ 45,774 Service cost 1,063 446 1,588 784 Interest cost 6,888 1,057 4,886 482 Actuarial loss (gain) 3,229 2,738 ( 45,932 ) ( 13,181 ) Benefits paid ( 10,807 ) ( 947 ) ( 9,200 ) ( 863 ) Liability (gain) loss due to settlement — ( 254 ) — — Non-U.S. currency movement — 1,009 — ( 3,061 ) End of year 144,187 33,984 143,814 29,935 Change in plan assets: Fair value of plan assets: Beginning of year 111,760 2,087 149,578 2,017 Actual return on plan assets 8,613 43 ( 31,835 ) 153 Company contributions 3,051 1,028 3,217 949 Benefits paid ( 10,807 ) ( 947 ) ( 9,200 ) ( 863 ) Settlements gain — ( 254 ) — — Non-U.S. currency movement — ( 28 ) — ( 169 ) End of year 112,617 1,929 111,760 2,087 Funded status $ ( 31,570 ) $ ( 32,055 ) $ ( 32,054 ) $ ( 27,848 ) The following table provides amounts recorded within the account line items of the statements of financial position as of December 31: 2023 2022 United States Foreign United States Foreign (in thousands) Retirement plans assets $ 11,504 $ — $ 11,761 $ — Accrued employees’ compensation and withholdings ( 3,110 ) ( 1,255 ) ( 3,055 ) ( 1,191 ) Retirement plans liabilities ( 39,964 ) ( 30,800 ) ( 40,760 ) ( 26,657 ) Funded status $ ( 31,570 ) $ ( 32,055 ) $ ( 32,054 ) $ ( 27,848 ) The accumulated benefit obligation for the United States defined benefit pension plans was $ 142.2 million and $ 140.6 million at December 31, 2023 and 2022 , respectively. The accumulated benefit obligation for foreign defined benefit pension plans was $ 32.6 million and $ 28.6 million at December 31, 2023 and 2022, respectively. Information for pension plans with an accumulated benefit obligation in excess of plan assets as of December 31: 2023 2022 United States Foreign United States Foreign (in millions) Projected benefit obligation $ 43.1 $ 34.0 $ 43.8 $ 29.9 Accumulated benefit obligation 42.6 32.5 42.3 28.6 Fair value of plan assets — 1.9 — 2.1 Expense For the years ended December 31, 2023, 2022, and 2021, Teradyne’s net periodic pension cost (income) was comprised of the following: 2023 2022 2021 United Foreign United Foreign United Foreign (in thousands) Components of Net Periodic Pension Cost (Income): Service cost $ 1,063 $ 446 $ 1,588 $ 784 $ 1,784 $ 941 Interest cost 6,888 1,057 4,886 482 4,427 337 Expected return on plan assets ( 5,194 ) ( 45 ) ( 2,927 ) ( 75 ) ( 3,858 ) ( 67 ) Net actuarial loss (gain) 18 2,735 ( 11,170 ) ( 13,259 ) 643 ( 2,223 ) Settlement (gain) loss ( 209 ) 5 — — ( 204 ) — Total net periodic pension cost (income) $ 2,566 $ 4,198 $ ( 7,623 ) $ ( 12,068 ) $ 2,792 $ ( 1,012 ) Weighted Average Assumptions to Determine Net Periodic Pension Cost at January 1: 2023 2022 2021 United Foreign United Foreign United Foreign Discount rate 3.5 % 3.5 % 2.5 % 1.1 % 2.2 % 0.7 % Expected return on plan assets 4.8 1.8 2.0 4.0 2.4 3.5 Salary progression rate 2.4 2.1 2.4 2.2 2.4 2.3 Weighted Average Assumptions to Determine Pension Obligations at December 31: 2023 2022 United States Foreign United States Foreign Discount rate 4.7 % 3.0 % 4.9 % 3.5 % Salary progression rate 2.5 2.4 2.5 2.1 In developing the expected return on plan assets assumption, Teradyne evaluates input from its investment manager and pension consultants, including their forecast of asset class return expectations. Teradyne believes that 4.75 % was an appropriate rate to use for fiscal year 2023 for the U.S. Qualified Pension Plan (“U.S. Plan”). Teradyne recognizes net actuarial gains and losses and the change in the fair value of the plan assets in its operating results in the year in which they occur or upon any interim remeasurement of the plans. Teradyne calculates the expected return on plan assets using the fair value of the plan assets. Actuarial gains and losses are generally measured annually as of December 31 and, accordingly, recorded during the fourth quarter of each year or upon any interim remeasurement of the plans. The discount rate utilized to determine future pension obligations for the U.S. Plan is based on FTSE Pension Index adjusted for the plan’s expected cash flows and was 4.7 % at December 31, 2023 , down from 4.9 % at December 31, 2022. Plan Assets As of December 31, 2023 , the fair value of Teradyne’s pension plans’ assets totaled $ 114.5 million, of which $ 112.6 million was related to the U.S. Plan and $ 1.9 million was related to the Taiwan defined benefit pension plan. Substantially all of Teradyne’s pension plans’ assets are held in individual trusts, which were established for the investment of assets of Teradyne’s sponsored retirement plans. The following table provides weighted average pension asset allocation by asset category at December 31, 2023 and 2022: 2023 2022 United States Foreign United States Foreign Fixed income securities 94.0 % — % 94.0 % — % Equity securities 5.0 — 5.0 — Other 1.0 100.0 1.0 100.0 100.0 % 100.0 % 100.0 % 100.0 % The assets of the U.S. Plan are overseen by the Teradyne Fiduciary Committee which is comprised of members of senior management drawn from appropriate diversified levels of the management team. The Fiduciary Committee is responsible for setting the policy that provides the framework for management of the U.S. Plan assets. In accordance with its responsibilities, the Fiduciary Committee meets on a regular basis to review the performance of the U.S. Plan assets and compliance with the investment policy. The policy sets forth an investment structure for managing U.S. Plan assets, including setting the asset allocation ranges, which are expected to provide an appropriate level of overall diversification required to maximize the long-term return on plan assets for a prudent and reasonable level of risk given prevailing market conditions, total investment return over the long term, and preservation of capital, while maintaining sufficient liquidity to pay the benefits of the U.S. Plan. The investment portfolio will not, at any time, have a direct investment in Teradyne stock. It may have indirect investment in Teradyne stock, if one of the funds selected by the investment manager invests in Teradyne stock. In developing the asset allocation ranges, third party asset allocation studies are periodically performed that consider the current and expected positions of the plan assets and funded status. Based on this study and other appropriate information, the Fiduciary Committee establishes asset allocation ranges taking into account acceptable risk targets and associated returns. The investment return objectives are to avoid excessive volatility and produce a rate of return that at least matches the Policy Index identified below. The manager’s investment performance is reviewed at least annually. Results for the total portfolio and for each major category of assets are evaluated in comparison with appropriate market indices and the Policy Index. The target asset allocation and the index for each asset category for the U.S. Plan, per the investment policy, are as follows: Asset Category: Policy Index: Target U.S. corporate fixed income Bloomberg U.S. Corporate A or Better Index, 20+ Year Index 43 % U.S. corporate fixed income Bloomberg U.S. Corporate A or Better Index, 5 - 20 Year Index 32 U.S. government fixed income Bloomberg U.S. 3 - 10 year Treasury Bond Index 14 Global equity MSCI World Index 5 High yield fixed income ICE BofA BB-B U.S. High Yield Constrained Index 5 Cash ICE BofA 3 -Month Treasury Bill Index 1 Teradyne’s U.S. Plan invests primarily in common trust funds. Units held in the common trust funds are valued at the unit price as reported by the investment manager based on the asset value of the underlying investments; underlying investments in equity securities are valued at the last reported sales price, and underlying investments in fixed-income securities are generally valued using methods based upon market transactions for comparable securities. During the years ended December 31, 2023 and December 31, 2022, there were no transfers of pension assets in or out of Level 1, Level 2, and Level 3. The fair value of pension plan assets by asset category and by level at December 31, 2023 and December 31, 2022 were as follows: December 31, 2023 United States Foreign Level 1 Level 2 Level 3 Total Level 1 Level 2 Level 3 Total (in thousands) Fixed income securities: Corporate debt securities $ — $ 89,971 $ — $ 89,971 $ — $ — $ — $ — U.S. government securities — 15,817 — 15,817 — — — — Global equity — 5,691 — 5,691 — — — — Other — — — — — 1,929 — 1,929 Cash and cash equivalents 1,138 — — 1,138 — — — — Total $ 1,138 $ 111,479 $ — $ 112,617 $ — $ 1,929 $ — $ 1,929 December 31, 2022 United States Foreign Level 1 Level 2 Level 3 Total Level 1 Level 2 Level 3 Total (in thousands) Fixed income securities: Corporate debt securities $ — $ 89,403 $ — $ 89,403 $ — $ — $ — $ — U.S. government securities — 15,631 — 15,631 — — — — Global equity — 5,579 — 5,579 — — — — Other — — — — — 2,087 — 2,087 Cash and cash equivalents 1,147 — — 1,147 — — — — Total $ 1,147 $ 110,613 $ — $ 111,760 $ — $ 2,087 $ — $ 2,087 Contributions Teradyne’s funding policy is to make contributions to the plans in accordance with local laws and to the extent that such contributions are tax deductible. During 2023 , Teradyne contributed $ 3.1 million to the U.S. supplemental executive defined benefit pension plan and $ 1.0 million to certain qualified plans for non-U.S. subsidiaries. During 2022, Teradyne contributed $ 3.2 million to the U.S. supplemental executive defined benefit pension plan and $ 0.9 million to certain qualified plans for non-U.S. subsidiaries. In 2024, contributions to the U.S. supplemental executive defined benefit pension plan and certain qualified plans from non-U.S. subsidiaries will be approximately $ 3.1 million and $ 1.4 million, respectively. Contributions to the U.S. supplemental executive defined benefit pension plan and certain non-U.S. subsidiaries qualified plans will be approximately $ 6.6 million and $ 2.3 million, respectively, in 1 to 3 years, $ 7.1 million and $ 2.5 million, respectively, in 3 to 5 years and $ 16.9 million and $ 7.9 million, respectively, thereafter. Expected Future Pension Benefit Payments Future benefit payments are expected to be paid as follows: United States Foreign (in thousands) 2024 $ 10,210 $ 1,312 2025 9,720 1,068 2026 9,863 1,191 2027 10,792 1,301 2028 10,795 1,238 2029-2032 51,857 8,832 Postretirement Benefit Plans In addition to receiving pension benefits, U.S. Teradyne employees 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 primarily to those employees. During the twelve months ended December 31, 2023, Teradyne recorded special termination benefit charges associated with a voluntary early retirement program. The December 31 balances of the postretirement assets and obligations are shown below: 2023 2022 (in thousands) Assets and Obligations Change in benefit obligation: Projected benefit obligation: Beginning of year $ 5,345 $ 7,210 Service cost 34 64 Interest cost 299 177 Actuarial loss (gain) 155 ( 1,155 ) Benefits paid ( 1,413 ) ( 950 ) Special termination benefits 2,513 — End of year 6,933 5,345 Change in plan assets: Fair value of plan assets: Beginning of year — — Company contributions 1,413 950 Benefits paid ( 1,413 ) ( 950 ) End of year — — Funded status $ ( 6,933 ) $ ( 5,345 ) The following table provides amounts recorded within the account line items of financial position as of December 31: 2023 2022 (in thousands) Accrued employees’ compensation and withholdings $ ( 1,508 ) $ ( 853 ) Retirement plans liabilities ( 5,425 ) ( 4,492 ) Funded status $ ( 6,933 ) $ ( 5,345 ) The following table provides amounts recognized in accumulated other comprehensive income (loss) as of December 31: 2023 2022 (in thousands) Prior service credit, before tax $ ( 23 ) $ ( 31 ) Deferred taxes ( 1,691 ) ( 1,689 ) Total recognized in other comprehensive income (loss), net of tax $ ( 1,714 ) $ ( 1,720 ) Expense For the years ended December 31, 2023, 2022, and 2021, Teradyne’s net periodic postretirement benefit cost (income) was comprised of the following: 2023 2022 2021 (in thousands) Components of Net Periodic Postretirement Benefit Cost (income): Service cost $ 34 $ 64 $ 64 Interest cost 299 177 170 Amortization of prior service credit ( 9 ) ( 9 ) ( 9 ) Net actuarial loss (gain) 155 ( 1,155 ) ( 433 ) Special termination benefits 2,513 — — Total net periodic postretirement benefit cost (income) 2,992 ( 923 ) ( 208 ) Changes in Plan Assets and Benefit Obligations Recognized in Other Reversal of amortization items: Prior service credit 9 9 9 Total recognized in other comprehensive income 9 9 9 Total recognized in net periodic postretirement cost (income) and other $ 3,001 $ ( 914 ) $ ( 199 ) Weighted Average Assumptions to Determine Net Periodic Postretirement Benefit Income as of January 1: 2023 2022 2021 Discount rate 5.0 % 2.6 % 2.2 % Initial health care cost trend rate 7.2 7.3 7.3 Ultimate health care cost trend rate 4.5 4.5 4.5 Year in which ultimate health care cost trend rate is reached 2032 2029 2029 Weighted Average Assumptions to Determine Postretirement Benefit Obligation as of December 31: 2023 2022 2021 Discount rate 4.7 % 5.0 % 2.6 % Initial health care trend 7.7 7.2 7.3 Ultimate health care trend 4.5 4.5 4.5 Medical cost trend rate decrease to ultimate rate in year 2033 2032 2029 Contributions Contributions to the U.S. postretirement benefit plan will be approximately $ 1.5 million in 2024, $ 1.6 million in 1 to 3 years, $ 1.2 million in 3 to 5 years and $ 2.0 million, thereafter. Expected Future Benefit Payments Future benefit payments are expected to be paid as follows: Benefit Payments (in thousands) 2024 $ 1,508 2025 924 2026 701 2027 637 2028 568 2029-2032 2,004

Stock-Based Compensation

Stock-Based Compensation	12 Months Ended
	Dec. 31, 2023
Share-Based Payment Arrangement [Abstract]
Stock-Based Compensation	Q. STOCK-BASED COMPENSATION Stock Compensation Plans 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 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) permanent disability or death or (2) retirement or termination other than for cause, after attaining both at least age sixty and at least ten years of service, 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 . During 2023, 2022 and 2021 , Teradyne granted 0.5 million, 0.4 million and 0.3 million of service-based restricted stock unit awards to employees at a weighted average grant date fair value of $ 102.45 , $ 109.42 , and $ 114.16 , respectively. During 2023, 2022 and 2021 , Teradyne granted 0.1 million of service-based restricted stock unit awards to non-employee directors at a weighted average grant date fair value of $ 90.50 , $ 105.93 , and $ 128.70 , respectively. During 2023, 2022 and 2021 , Teradyne granted 0.1 million of PBIT PRSUs with a grant date fair value of $ 102.91 , $ 110.84 and $ 113.65 , respectively. During 2023, 2022 and 2021 , Teradyne granted 0.1 million TSR PRSUs, with a grant date fair value of $ 139.04 , $ 101.06 , and $ 125.02 , respectively. The fair value was estimated using the Monte Carlo simulation model with the following assumptions: 2023 2022 2021 Risk-free interest rate 4.0 % 1.4 % 0.2 % Teradyne volatility-historical 49.7 % 47.1 % 43.9 % NYSE Composite Index volatility-historical 24.1 % 22.7 % 22.9 % Dividend yield 0.4 % 0.4 % 0.4 % Expected volatility was based on the historical volatility of Teradyne’s stock and the NYSE Composite Index for each of the 2023, 2022 and 2021 grants 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 each of the grants. Dividend yield was based upon an estimated annual dividend amount of $ 0.44 per share for 2023, $ 0.44 per share for 2022, and $ 0.40 per share for 2021, divided by Teradyne’s stock price on the grant date of $ 104.12 for the 2023 grants, $ 112.12 for the 2022 grants, and $ 113.48 for the 2021 grants. During 2023, 2022 and 2021 , Teradyne granted 0.1 million of service-based stock options to executive officers at a weighted average grant date fair value of $ 41.23 , $ 39.01 , and $ 36.60 , respectively. The fair value of stock options was estimated using the Black-Scholes option-pricing model with the following assumptions: 2023 2022 2021 Expected life (years) 4.0 4.0 5.0 Risk-free interest rate 3.8 % 1.6 % 0.4 % Volatility-historical 46.6 % 43.7 % 37.8 % Dividend yield 0.4 % 0.4 % 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 $ 0.44 per share divided by Teradyne’s stock on the grant date of $ 104.15 for the 2023 grant, and $ 112.12 for the 2022 grant, and $ 0.40 per share divided by Teradyne’s stock price on the grant date of $ 113.48 for the 2021 grants. Stock compensation plan activity for the years 2023, 2022 and 2021, is as follows: 2023 2022 2021 (in thousands) Restricted Stock Units: Non-vested at January 1 1,317 1,417 1,789 Awarded 728 660 447 Vested ( 609 ) ( 709 ) ( 749 ) Forfeited ( 58 ) ( 51 ) ( 70 ) Non-vested at December 31 1,378 1,317 1,417 Stock Options: Outstanding at January 1 188 171 216 Granted 41 42 34 Exercised ( 56 ) ( 25 ) ( 78 ) Forfeited ( 2 ) — ( 1 ) Expired — — — Outstanding at December 31 171 188 171 Vested and expected to vest at December 31 171 188 171 Exercisable at December 31 68 69 30 Total shares available for the years 2023, 2022 and 2021: 2023 2022 2021 (in thousands) Shares available: Available for grant at January 1 5,062 5,713 6,123 Options granted ( 41 ) ( 42 ) ( 34 ) Options forfeited 2 — 1 Restricted stock units awarded ( 728 ) ( 660 ) ( 447 ) Restricted stock units forfeited 58 51 70 Available for grant at December 31 4,353 5,062 5,713 Weighted average restricted stock unit award date fair value information for the years 2023, 2022 and 2021, is as follows: 2023 2022 2021 Non-vested at January 1 $ 88.71 $ 67.97 $ 47.84 Awarded 105.05 108.74 115.51 Vested 75.55 54.27 43.99 Forfeited 102.12 85.71 65.52 Non-vested at December 31 $ 101.00 $ 88.71 $ 67.97 Restricted stock unit awards aggregate intrinsic value information at December 31 for the years 2023, 2022 and 2021 is as follows: 2023 2022 2021 (in thousands) Vested $ 62,001 $ 95,408 $ 101,679 Outstanding 149,504 115,087 231,763 Expected to vest 135,238 108,666 231,246 Restricted stock units weighted average remaining contractual terms (in years) information at December 31 for the years 2023, 2022 and 2021 is as follows: 2023 2022 2021 Outstanding 1.13 0.99 0.89 Expected to vest 1.13 0.99 0.89 Weighted average stock options exercise price information for the year ended December 31, 2023 is as follows: 2023 Outstanding at January 1 $ 76.52 Options granted 104.15 Options exercised 39.71 Options forfeited 112.57 Options cancelled 113.03 Outstanding at December 31 94.85 Exercisable at December 31 81.53 The total cash received from employees as a result of employee stock options exercised during the years ended December 31, 2023, 2022 and 2021 , was $ 2.2 million, $ 0.9 million, and $ 3.1 million, respectively. In connection with these exercises, the tax benefit realized by Teradyne for the years ended December 31, 2023, 2022 and 2021 , was $ 0.2 million, $ 0.1 million, and $ 0.4 million, respectively. Stock option aggregate intrinsic value information for the years ended December 31, 2023, 2022 and 2021 is as follows: 2023 2022 2021 (in thousands) Exercised $ 3,901 $ 2,030 $ 6,345 Outstanding 2,647 3,963 17,356 Expected to vest 696 1,583 13,500 Vested and exercisable 1,950 2,380 3,856 Stock options weighted average remaining contractual terms (in years) information at December 31, for the years 2023, 2022 and 2021 is as follows: 2023 2022 2021 Outstanding 4.4 4.2 4.4 Expected to vest 5.1 4.8 4.8 Vested and exercisable 3.4 3.1 2.5 As of December 31, 2023 , total unrecognized expense related to non-vested restricted stock unit awards and stock options was $ 73.7 million and is expected to be recognized over a weighted average period of 2.5 years. Employee Stock Purchase Plan Under the ESPP, eligible employees may purchase shares of common stock through regular payroll deductions of up to 10 % of their compensation, to a maximum of shares with a fair market value of $ 25,000 per calendar year, not to exceed 6,000 shares. Under the plan, the price paid for the common stock is equal to 85 % of the stock price on the last business day of the six-month purchase period. In July 2023, 0.2 million shares of common stock were issued to employees who participated in the plan during the first half of 2023 at the price of $ 94.64 per share. In January 2024, Teradyne issued 0.2 million shares of common stock to employees who participated in the plan during the second half of 2023 at the price of $ 92.25 per share. In July 2022, 0.2 million shares of common stock were issued to employees who participated in the plan during the first half of 2022 at the price of $ 76.12 per share. In January 2023, Teradyne issued 0.2 million shares of common stock to employees who participated in the plan during the second half of 2022 at the price of $ 74.25 per share. In July 2021, 0.1 million shares of common stock were issued to employees who participated in the plan during the first half of 2021 at the price of $ 113.87 per share. In January 2022, Teradyne issued 0.1 million shares of common stock to employees who participated in the plan during the second half of 2021 at the price of $ 139.00 per share. As of December 31, 2023 , there were 3.5 million shares available for grant under the ESPP. The following table provides the effect to income from operations for recording stock-based compensation for the years ended December 31, 2023, 2022, and 2021: 2023 2022 2021 (in thousands) Cost of revenues $ 4,208 $ 4,050 $ 4,196 Engineering and development 10,659 9,992 9,783 Selling and administrative 42,815 34,186 31,664 Stock-based compensation 57,682 48,228 45,643 Income tax benefit ( 10,397 ) ( 11,493 ) ( 14,389 ) Total stock-based compensation expense after income taxes $ 47,285 $ 36,735 $ 31,254

Savings Plan

Savings Plan	12 Months Ended
	Dec. 31, 2023
Defined Contribution Plan [Abstract]
Savings Plan	R. SAVINGS PLAN Teradyne sponsors a defined contribution employee retirement savings plan (“Savings Plan”) covering substantially all U.S. employees. Under the Savings Plan, employees may contribute up to 20 % of their compensation (subject to Internal Revenue Service limitations). The Savings Plan provides for a discretionary employer match that is determined each year. In 2023, 2022 and 2021 , Teradyne matched 100 % of eligible employee contributions up to 4 % of their compensation for employees not accruing benefits in the U.S. Qualified Pension Plan. There was no match for employees still actively accruing benefits in the U.S. Qualified Pension Plan. Teradyne’s contributions vest 25 % per year for the first four years of employment, and contributions for those employees with four years of service vest immediately. In addition, Teradyne sponsors an unfunded U.S. Supplemental Savings Plan to provide savings benefits in excess of those allowed by the Employee Retirement Income Security Act of 1974 and the Internal Revenue Code. The provisions of this plan are the same as the Savings Plan. The liability for the U.S. Supplemental Savings Plan at December 31, 2023 and 2022 , was $ 55.9 million and $ 44.1 million, respectively, and is included in retirement plan liabilities. Teradyne contributes to defined contributions savings plans for its foreign employees. Under Teradyne’s savings plans, amounts charged to the statements of operations for the years ended December 31, 2023, 2022, and 2021 were $ 30.5 million, $ 30.1 million, and $ 26.9 million, respectively.

Income Taxes

Income Taxes	12 Months Ended
	Dec. 31, 2023
Income Tax Disclosure [Abstract]
Income Taxes	S. INCOME TAXES The components of income before income taxes and the provision (benefit) for income taxes as shown in the consolidated statements of operations were as follows: 2023 2022 2021 (in thousands) Income before income taxes: U.S. $ 307,997 $ 385,968 $ 403,451 Non-U.S. 217,575 454,417 757,504 $ 525,572 $ 840,385 $ 1,160,955 Provision (benefit) for income taxes: Current: U.S. Federal $ 58,063 $ 86,692 $ 58,218 Non-U.S. 54,037 74,204 105,153 State 2,362 2,681 300 114,462 163,577 163,671 Deferred: U.S. Federal ( 27,459 ) ( 36,739 ) ( 15,106 ) Non-U.S. ( 8,584 ) 1,232 ( 4,300 ) State ( 1,599 ) ( 3,186 ) 2,101 ( 37,642 ) ( 38,693 ) ( 17,305 ) Total provision for income taxes: $ 76,820 $ 124,884 $ 146,366 Income tax expense for 2023, 2022 and 2021 totaled $ 76.8 million, $ 124.9 million, and $ 146.4 million, respectively. The effective tax rate for 2023, 2022 and 2021 was 14.6 %, 14.9 % and 12.6 %, respectively. At December 31, 2023 , Teradyne’s remaining tax liability resulting from the U.S. one-time transition tax on the mandatory deemed repatriation of foreign earnings amounts to $ 59.1 million. Teradyne will pay approximately $ 14.8 million related to the transition tax in 2024, and $ 44.3 million in 1 to 3 years. Teradyne has made an accounting policy election to account for global intangible low-taxed income (“GILTI”) as a component of tax expense in the period in which Teradyne is subject to the rules and therefore did not provide any deferred tax impacts of GILTI in its consolidated financial statements. On July 27, 2015, in Altera Corp. (“Altera”) v. Commissioner, the U.S. Tax Court issued an opinion invalidating the regulations relating to the treatment of stock-based compensation expense in an intercompany cost-sharing arrangement. A final decision was issued by the Tax Court in December 2015. The IRS appealed the decision in June 2016. On July 24, 2018, the U.S. Court of Appeals for the Ninth Circuit (“Ninth Circuit”) issued a decision that was subsequently withdrawn and a reconstituted panel conferred on the appeal. On June 7, 2019, the Ninth Circuit upheld the cost-sharing regulations. On November 12, 2019, the Ninth Circuit denied Altera’s petition for rehearing of its case. Altera’s application for certiorari to the Supreme Court was declined on June 22, 2020. In the fourth quarter of 2021, Teradyne recognized approximately $ 2.5 million of tax benefit related to the inclusion of stock-based compensation in its intercompany cost-sharing arrangement. The decrease in the effective tax rate from 2022 to 2023 is primarily attributable to increases in benefit from tax credits and the U.S. foreign derived intangible income deduction. These decreases in expense were partially offset by a shift in the geographic distribution of income, which increased the income subject to taxation in higher tax rate jurisdictions relative to lower tax rate jurisdictions and a reduction in benefit from equity compensation. The increase in the effective tax rate from 2021 to 2022 is primarily attributable to a shift in the geographic distribution of income, which increased the income subject to taxation in higher tax rate jurisdictions relative to lower tax rate jurisdictions, increases in expense from U.S. global low-taxed income and increases in expense from non-deductible officer compensation. These increases in expense were partially offset by increases in benefits from the U.S. foreign derived intangible income deduction and tax credits. A reconciliation of the effective tax rate for the years 2023, 2022 and 2021 is as follows: 2023 2022 2021 U.S. statutory federal tax rate 21.0 % 21.0 % 21.0 % Foreign taxes 2.5 ( 1.9 ) ( 4.5 ) Non-deductible officers’ compensation 1.1 1.3 0.8 U.S. global intangible low-taxed income 0.8 1.2 0.6 State income taxes, net of federal tax benefit 0.1 ( 0.1 ) 0.2 U.S. research and development credit ( 4.2 ) ( 1.8 ) ( 1.4 ) U.S. foreign derived intangible income ( 3.9 ) ( 3.1 ) ( 2.3 ) Foreign tax credits ( 3.3 ) ( 1.0 ) ( 0.5 ) Equity compensation ( 0.4 ) ( 1.1 ) ( 1.0 ) Other, net 0.9 0.4 ( 0.3 ) 14.6 % 14.9 % 12.6 % 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 attributable to the Singapore tax holiday for the years ended December 31, 2023, 2022 and 2021 were $ 1.4 million or $ 0.01 per diluted share, $ 16.0 million or $ 0.09 per diluted share, and $ 33.3 million or $ 0.18 per diluted share, respectively. In November 2020, Teradyne entered into an agreement with the Singapore Economic Development Board which extended our 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 . Teradyne does not anticipate entering into a similar tax holiday agreement with the Singapore Economic Development Board when the current agreement expires. Significant components of Teradyne’s deferred tax assets (liabilities) as of December 31, 2023 and 2022 were as follows: 2023 2022 (in thousands) Deferred tax assets: Tax credits $ 112,571 $ 105,503 Research and development 82,571 47,760 Accruals 25,644 30,747 Pension liabilities 24,997 21,335 Lease liabilities 21,167 18,679 Inventory valuations 19,289 22,554 Deferred revenue 13,807 14,909 Equity compensation 7,179 6,578 Vacation accrual 6,096 5,856 Net operating loss carryforwards 5,737 1,857 Investment impairment 3,292 3,292 Intangible assets 2,323 350 Marketable securities 128 2,283 Other 953 2,520 Gross deferred tax assets 325,754 284,223 Less: valuation allowance ( 109,251 ) ( 103,807 ) Total deferred tax assets $ 216,503 $ 180,416 Deferred tax liabilities: Right of use assets $ ( 19,016 ) $ ( 16,607 ) Depreciation ( 16,681 ) ( 19,078 ) Contingent consideration ( 5,214 ) ( 5,214 ) Total deferred tax liabilities $ ( 40,911 ) $ ( 40,899 ) Net deferred assets $ 175,592 $ 139,517 As of December 31, 2023 and 2022, Teradyne evaluated the likelihood that it would realize deferred income taxes to offset future taxable income and concluded that it is more likely than not that the majority of its deferred tax assets will be realized through consideration of both the positive and negative evidence. At December 31, 2023 and 2022 , Teradyne maintained a valuation allowance for certain deferred tax assets of $ 109.3 million and $ 103.8 million, respectively, primarily related to state net operating losses and state tax credit carryforwards, due to the uncertainty regarding their realization. Adjustments could be required in the future if Teradyne estimates that the amount of deferred tax assets to be realized is more or less than the net amount recorded. At December 31, 2023, Teradyne had tax effected operating loss carryforwards that expire in the following years: State Foreign (in thousands) 2024 $ 6 $ — 2025 4 — 2026 — — 2027 — — 2028 23 83 2029-2033 121 500 2034-2038 31 — Beyond 2038 — — Non-expiring 30 4,939 Total $ 215 $ 5,522 Teradyne has approximately $ 147.1 million of tax credit carryforwards including federal business tax credits of approximately $ 3.4 million which expire in 2028 through 2033, and state tax credits of $ 143.8 million, of which $ 76.5 million do not expire and the remainder expires in the years 2023 through 2043 . Teradyne’s gross unrecognized tax benefits for the years ended December 31, 2023, 2022 and 2021 were as follows: 2023 2022 2021 (in thousands) Beginning balance as of January 1 $ 15,608 $ 14,465 $ 17,903 Additions: Tax positions for current year — 1,398 1,417 Tax positions for prior years 3,024 13 30 Reductions: Tax positions for prior years ( 26 ) ( 56 ) ( 1,639 ) Expiration of statutes — ( 212 ) ( 3,246 ) Ending balance as of December 31 $ 18,606 $ 15,608 $ 14,465 Current year additions primarily relate to foreign transfer pricing and prior year reductions relate to state research credits. Of the $ 18.6 million of unrecognized tax benefits as of December 31, 2023 , $ 12.9 million would impact the consolidated income tax rate if ultimately recognized. The remaining $ 5.7 million would impact deferred taxes if recognized. As of December 31, 2023 , Teradyne estimates that it is reasonably possible that the balance of unrecognized tax benefits may decrease approximately $ 2.8 million in the next twelve months as a result of the resolution of an audit and a lapse of statutes of limitation. The estimated decrease relates to transfer pricing and state research credits. Teradyne records all interest and penalties related to income taxes as a component of income tax expense. Accrued interest and penalties related to income tax items at December 31, 2023 and 2022 amounted to $ 1.3 million and $ 0.4 million, respectively. For the years ended December 31, 2023, 2022 and 2021 , expense of $ 0.9 million, expense of $ 0.1 million, and benefit of $ 0.9 million, respectively, was recorded for interest and penalties related to income tax items. Teradyne is subject to U.S. federal income tax, as well as income tax in multiple state, local and foreign jurisdictions. As of December 31, 2023, all material state and local income tax matters have been concluded through 2018, all material federal income tax matters have been concluded through 2017 and all material foreign income tax matters have been concluded through 2015. However, in some jurisdictions, including the United States, operating losses and tax credits may be subject to adjustment until such time as they are utilized and the year of utilization is closed to adjustment. As of December 31, 2023, Teradyne is not permanently reinvested with respect to the unremitted earnings of non-U.S. subsidiaries to the extent that those earnings exceed local statutory and operational requirements. Remittance of those earnings is not expected to result in material income tax. 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 future periods. Based upon preliminary calculations for calendar year 2024, Teradyne anticipates it will meet the safe harbors in most jurisdictions, and any remaining tax under the rules should be immaterial.

Operating Segment, Geographic a

Operating Segment, Geographic and Significant Customer Information	12 Months Ended
	Dec. 31, 2023
Segment Reporting [Abstract]
Operating Segment, Geographic and Significant Customer Information	T. OPERATING SEGMENT, GEOGRAPHIC AND SIGNIFICANT CUSTOMER 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.” Segment information for the years ended December 31, 2023, 2022 and 2021 is as follows: Semiconductor System Robotics Wireless Segment Corporate Consolidated (in thousands) 2023 Revenues $ 1,818,636 $ 338,197 $ 375,183 $ 144,282 $ 2,676,298 $ — $ 2,676,298 Income (loss) before taxes (1)(2) 453,320 94,073 ( 54,251 ) 30,568 523,710 1,862 525,572 Total assets (3) 1,329,522 182,084 737,323 68,291 2,317,220 1,169,604 3,486,824 Property additions 113,415 3,643 40,739 1,845 159,642 — 159,642 Depreciation and amortization expense 77,745 3,801 25,527 4,043 111,116 ( 230 ) 110,886 2022 Revenues $ 2,080,590 $ 469,346 $ 403,138 $ 201,720 $ 3,154,794 $ 251 $ 3,155,045 Income (loss) before taxes (1)(2) 634,488 166,879 ( 16,244 ) 66,820 851,943 ( 11,558 ) 840,385 Total assets (3) 1,382,623 165,925 665,638 94,298 2,308,484 1,192,768 3,501,252 Property additions 126,898 7,275 25,712 3,364 163,249 — 163,249 Depreciation and amortization expense 76,532 3,235 25,339 4,991 110,097 578 110,675 2021 Revenues $ 2,642,342 $ 467,739 $ 375,905 $ 216,895 $ 3,702,881 $ — $ 3,702,881 Income (loss) before taxes (1)(2) 976,988 163,064 ( 8,167 ) 83,543 1,215,428 ( 54,473 ) 1,160,955 Total assets (3) 1,245,596 170,954 701,196 107,513 2,225,259 1,584,166 3,809,425 Property additions 115,618 3,905 9,821 3,128 132,472 — 132,472 Depreciation and amortization expense 75,982 3,156 27,336 6,055 112,529 12,956 125,485 (1) Included in Corporate and Eliminations are interest income, interest expense, net foreign exchange gains (losses), intercompany eliminations, pension and postretirement plan actuarial gains (losses), legal and environmental fees, contingent consideration adjustments, acquisition and divestiture related expenses, contract termination settlement charge, an expense for the modification of Teradyne's former chief executive officer's outstanding equity awards, and loss on convertible debt conversions in 2021. (2) Included in income (loss) before taxes are charges and credits related to restructuring and other, inventory charges and loss on convertible debt conversions in 2021. (3) Total assets are attributable to each segment. Semiconductor Test includes $ 34.8 million of total assets classified as assets held for sale. See Note E: “Assets held for sale” for additional information. 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 Years Ended December 31, 2023 2022 2021 (in thousands) Semiconductor Test: Cost of revenues—inventory charge $ 22,482 $ 21,456 $ 6,661 Restructuring and other—employee severance 5,666 — — System Test: Cost of revenues—inventory charge $ 1,855 $ 1,730 $ 641 Restructuring and other—employee severance 1,541 $ — $ — Robotics: Cost of revenues—inventory charge $ 2,275 $ 3,668 $ 6,403 Restructuring and other—employee severance 3,707 2,115 1,210 Restructuring and other—acquisition & divestiture related expenses — — 1,000 Wireless: Cost of revenues—inventory charge $ 1,746 $ 4,598 $ 1,770 Corporate and Eliminations: Selling and administrative—equity modification charge $ 5,889 $ — $ — Restructuring and other—employee severance 3,599 — — Restructuring and other—acquisition & divestiture related expenses 3,562 — ( 513 ) Restructuring and other—contract termination 1,511 — — Restructuring and other—environmental and legal liabilities 1,100 2,700 1,971 Other (income) expense, net—gain on foreign exchange option ( 7,464 ) — — Restructuring and other—legal settlement charge — 14,700 12,000 Restructuring and other—gain on sale of asset — ( 3,410 ) — Other (income) expense, net—loss on convertible debt conversion — — 28,828 Restructuring and other—AutoGuide contingent consideration adjustment — — ( 7,227 ) Information as to Teradyne’s revenues by country is as follows: 2023 2022 2021 (in thousands) Revenues from customers (1): United States $ 433,661 $ 469,948 $ 392,626 Korea 394,690 544,816 502,167 Taiwan 384,842 626,424 1,117,874 China 314,899 491,798 631,963 Japan 281,742 162,920 166,231 Europe 273,784 268,384 259,954 Philippines 189,419 124,107 166,838 Singapore 116,969 99,503 121,582 Thailand 91,818 137,356 138,812 Malaysia 89,197 142,203 136,774 Rest of the World 105,277 87,586 68,060 $ 2,676,298 $ 3,155,045 $ 3,702,881 (1) Revenues attributable to a country are based on location of customer site. In 2023, revenues from Texas Instruments Inc., a customer of our Semiconductor Test segment, accounted for 10 % of our consolidated revenues. In 2021, revenues from Taiwan Semiconductor Manufacturing Company Ltd., a customer of Teradyne’s Semiconductor Test segment, accounted for 12 %, of Teradyne’s consolidated revenues. Teradyne estimates consolidated revenues driven by Qualcomm, a customer of our Semiconductor Test, System Test, and Wireless Test segments, combining direct and indirect sales, accounted for approximately 11 % of its consolidated revenues in 2022. Teradyne estimates consolidated revenues driven by one OEM customer, of our Semiconductor Test and Wireless Test segments, combining direct sales to that customer with sales to the customer’s OSATs (which include Taiwan Semiconductor Manufacturing Company Ltd.), accounted for 19 % in 2021. Long-lived assets by geographic area: United Foreign (1) Total (in thousands) December 31, 2023 (2) $ 322,445 $ 207,995 $ 530,440 December 31, 2022 $ 328,341 $ 164,076 $ 492,417 (1) As of December 31, 2023 and December 31, 2022, long-lived assets attributable to Denmark were $ 78.1 million and $ 42.5 million, respectively. (2) Includes $ 11.5 million of long-lived assets classified as assets held for sale. See Note E: “Assets held for sale” for additional information.

Stock Repurchase Program

Stock Repurchase Program	12 Months Ended
	Dec. 31, 2023
Disclosure of Repurchase Agreements [Abstract]
Stock Repurchase Program	U. STOCK REPURCHASE PROGRAM In January 2023, Teradyne’s Board of Directors cancelled the January 2021 repurchase program and approved a new repurchase program for up to $ 2.0 billion of common stock. In 2023, Teradyne repurchased 3.9 million shares of common stock for a total cost of $ 400.5 million at an average price of $ 102.47 per share. In 2022, Teradyne repurchased 7.3 million shares of common stock for $ 752.1 million at an average price of $ 103.69 per share. The cumulative repurchases under the January 2021 repurchase program as of December 31, 2022 were 12.0 million shares of common stock for $ 1,352.1 million at an average price per share of $ 112.44 . The total cost of shares acquired includes commissions and, starting in 2023, related excise tax, and is recorded as a reduction to retained earnings.

Subsequent Events

Subsequent Events	12 Months Ended
	Dec. 31, 2023
Subsequent Events [Abstract]
Subsequent Events	V. SUBSEQUENT EVENTS In January 2024, Teradyne’s Board of Directors declared a 9 % increase in the quarterly cash dividend to $ 0.12 per share to be paid on March 15, 2024 to shareholders of record as of February 16, 2024 . While Teradyne declared a quarterly cash dividend and authorized a share repurchase program, it may reduce or eliminate the cash dividend or share repurchase program in the future. Future cash dividends and stock repurchases are subject to the discretion of Teradyne’s Board of Directors which will consider, among other things, Teradyne’s earnings, capital requirements and financial condition.

Valuation and Qualifying Accoun

Valuation and Qualifying Accounts	12 Months Ended
	Dec. 31, 2023
SEC Schedule, 12-09, Valuation and Qualifying Accounts [Abstract]
Valuation and Qualifying Accounts	TERADYNE, INC. SCHEDULE II—VALUATION AND QUALIFYING ACCOUNTS Column A Column B Column C Column D Column E Column F Description Balance at Additions Other Deductions Balance at (in thousands) Valuation reserve deducted in the balance sheet Accounts receivable: 2023 Allowance for credit losses $ 1,955 $ 301 $ 23 $ 291 $ 1,988 2022 Allowance for credit losses $ 2,012 $ 500 $ ( 6 ) $ 551 $ 1,955 2021 Allowance for credit losses $ 2,034 $ 500 $ ( 27 ) $ 495 $ 2,012 Column A Column B Column C Column D Column E Column F Description Balance at Additions Other Deductions Balance at (in thousands) Valuation reserve deducted in the balance sheet Deferred taxes: 2023 Valuation allowance $ 103,807 $ 5,759 $ 59 $ 374 $ 109,251 2022 Valuation allowance $ 97,170 $ 7,652 $ 21 $ 1,036 $ 103,807 2021 Valuation allowance $ 84,962 $ 13,502 $ — $ 1,294 $ 97,170

Accounting Policies (Policies)

Accounting Policies (Policies)	12 Months Ended
	Dec. 31, 2023
Accounting Policies [Abstract]
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 Annual Report on Form 10-K. 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.
Revenue Recognition	Revenue Recognition Revenue from Contracts with Customers In accordance with ASC 606, Teradyne recognizes revenues, when or as control is transferred to a customer. Teradyne’s determination of revenue is dependent upon a five-step process outlined below. • Teradyne accounts for a contract with a customer when there is written approval, the contract is committed, the rights of the parties, including payment terms, are identified, the contract has commercial substance and consideration is probable of collection. • Teradyne periodically enters into contracts with customers in which a customer may purchase a combination of goods and services, such as products with extended warranty obligations. Teradyne determines performance obligations by assessing whether the products or services are distinct from the other elements of the contract. In order to be distinct, the product or service must perform either on its own or with readily available resources and must be separate within the context of the contract. • Teradyne determines the transaction price to be the amount of consideration to which Teradyne expects to be entitled to, which is generally at contractually stated prices. • Transaction price is allocated to each individual performance obligation based on the standalone selling price of that performance obligation. Teradyne uses standalone transactions when available to value each performance obligation. If standalone transactions are not available, Teradyne will estimate the standalone selling price through market assessments or cost plus a reasonable margin analysis. Any discounts from standalone selling price are spread proportionally to each performance obligation. • In order to determine the appropriate timing for revenue recognition, Teradyne first determines if the transaction meets any of three criteria for over time recognition. If the transaction meets the criteria for over time recognition, Teradyne recognizes revenue as the good or service is delivered. Teradyne uses input variables such as hours or months utilized or costs incurred to determine the amount of revenue to recognize in a given period. Input variables are used as they best align consumption with benefit to the customer. For transactions that do not meet the criteria for over time recognition, Teradyne will recognize revenue at a point in time based on an assessment of the five criteria for transfer of control. Teradyne has concluded that revenue should be recognized when shipped or delivered based on contractual terms. Typically, acceptance of Teradyne’s products and services is a formality as Teradyne delivers similar systems, instruments and robots to standard specifications. In cases where acceptance is not deemed a formality, Teradyne will defer revenue recognition until customer acceptance. Performance Obligations Products Teradyne products consist primarily of semiconductor test systems and instruments, defense/aerospace test instrumentation and systems, storage test systems and instruments, circuit-board test and inspection systems and instruments, wireless test systems and robotics products. Teradyne’s hardware is typically recognized at a point in time upon transfer of control to the customer. Services Teradyne services consist of extended warranties, training and application support, service agreements, post contract customer support (“PCS”) and replacement parts. Each service is recognized based on relative standalone selling price. Extended warranty, training and support, service agreements and PCS are recognized over time based on the period of service. Replacement parts are recognized at a point in time upon transfer of control to the customer. Teradyne does not allow customer returns or provide refunds to customers for any products or services. Teradyne products include a standard 12 -month warranty. This warranty is not considered a distinct performance obligation because it does not obligate Teradyne to provide a separate service to the customer and it cannot be purchased separately. Cost related to warranties are included in cost of revenues when product revenues are recognized. As of December 31, 2023 and 2022, deferred revenue and customer advances consisted of the following and are included in the short and long-term deferred revenue and customer advances: 2023 2022 (in thousands) Maintenance, service and training $ 66,458 $ 78,089 Customer advances, undelivered elements and other 35,731 59,147 Extended warranty 34,897 56,180 Total deferred revenue and customer advances $ 137,086 $ 193,416
Product Warranty	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: Amount (in thousands) Balance at December 31, 2020 $ 16,633 Accruals for warranties issued during the period 35,727 Accruals related to pre-existing warranties ( 6,846 ) Settlements made during the period ( 20,937 ) Balance at December 31, 2021 24,577 Accruals for warranties issued during the period 21,851 Accruals related to pre-existing warranties ( 5,618 ) Settlements made during the period ( 26,629 ) Balance at December 31, 2022 14,181 Accruals for warranties issued during the period 21,644 Accruals related to pre-existing warranties ( 1,576 ) Settlements made during the period ( 18,551 ) Balance at December 31, 2023 $ 15,698 When Teradyne receives revenue for extended warranties, beyond one year, it is 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: Amount (in thousands) Balance at December 31, 2020 $ 51,929 Deferral of new extended warranty revenue 43,597 Recognition of extended warranty deferred revenue ( 31,358 ) Balance at December 31, 2021 64,168 Deferral of new extended warranty revenue 33,686 Recognition of extended warranty deferred revenue ( 41,674 ) Balance at December 31, 2022 56,180 Deferral of new extended warranty revenue 14,330 Recognition of extended warranty deferred revenue ( 35,613 ) Balance at December 31, 2023 $ 34,897
Accounts Receivable and Allowance for Credit Losses	Accounts Receivable and Allowance for Credit Losses Trade accounts receivable are recorded at the invoiced amount and do not bear interest. Teradyne maintains allowances for estimated losses resulting from the inability of its customers to make required payments. Estimated allowances for credit losses are reviewed periodically taking into account the customer’s recent payment history, the customer’s current financial statements and other information regarding the customer’s creditworthiness. Account balances are written off against the allowance when it is determined the receivable will not be recovered. Teradyne sells certain trade accounts receivables on a non-recourse basis to third-party financial institutions pursuant to factoring agreements. Teradyne accounts for these transactions as sales of receivables and presents cash proceeds as a cash provided by operating activities in the consolidated statements of cash flows. Total trade accounts receivable sold under the factoring agreements were $ 243.5 million and $ 93.9 million during 2023 and 2022 , respectively. Factoring fees for the sales of receivables are recorded in interest expense and are not material.
Inventories	Inventories Inventories are stated at the lower of cost (first-in, first-out basis) or net realizable value. On a quarterly basis, Teradyne uses consistent methodologies to evaluate all inventories for net realizable value. Teradyne records a provision for both excess and obsolete inventory when such write-downs or write-offs are identified through the quarterly review process. The inventory valuation is based upon assumptions about future demand, product mix and possible alternative uses.
Investments	Investments Teradyne accounts for its investments in debt and equity securities in accordance with the provisions of ASC 320-10, “ Investments—Debt and Equity Securities .” ASC 320-10 requires that certain debt and equity securities be classified into one of three categories; trading, available-for-sale or held-to-maturity securities. On a quarterly basis, Teradyne reviews its investments to identify and evaluate those that have an indication of a potential other-than-temporary impairment. Factors considered in determining whether a loss is other-than-temporary include: • The length of time and the extent to which the market value has been less than cost; • The financial condition and near-term prospects of the issuer; and • The intent and ability to retain the investment in the issuer for a period of time sufficient to allow for any anticipated recovery in market value. Teradyne uses the market and income approach techniques to value its financial instruments and there were no changes in valuation techniques during the twelve months ended December 31, 2023 and 2022. Teradyne measures its debt and equity investments at fair value, in accordance with ASC 820-10, “ Fair Value Measurements and Disclosures. ” ASC 820-10 defines fair value as the price that would be received from the sale of an asset or paid to transfer a liability in an orderly transaction between market participants and requires that assets and liabilities carried at fair value be classified and disclosed in one of the following three categories: Level 1: Quoted prices in active markets for identical assets as of the reporting date; Level 2: Inputs other than Level 1, that are observable either directly or indirectly as of the reporting date. For example, a common approach for valuing fixed income securities is the use of matrix pricing. Matrix pricing is a mathematical technique used to value securities by relying on the securities’ relationship to other benchmark quoted prices, and is considered a Level 2 input; or Level 3: Unobservable inputs that are not supported by market data. Unobservable inputs are developed based on the best information available, which might include Teradyne’s own data. Teradyne’s debt investments are classified as Level 2, and equity investments are classified as Level 1. Acquisition-related contingent consideration is classified as Level 3. Teradyne determines the fair value of acquisition-related contingent consideration using a Monte Carlo simulation model. Assumptions utilized in the model include forecasted revenues, revenue volatility, earnings before interest and taxes, and discount rate.
Financial Assets and Financial Liabilities	Financial Assets and Financial Liabilities Teradyne records changes in fair value of equity securities directly in earnings and unrealized gains and losses in other (income) expense, net, in accordance with ASU 2016-01, “ Financial Instruments—Overall (Subtopic 825-10): Recognition and Measurement of Financial Assets and Financial Liabilities .”
Prepayments	Prepayments Prepayments consist of the following: 2023 (1) 2022 (in thousands) Contract manufacturer and supplier prepayments $ 502,257 $ 491,105 Prepaid maintenance and other services 17,592 14,545 Prepaid taxes 16,083 18,625 Other prepayments 13,038 8,687 Total prepayments $ 548,970 $ 532,962 (1) Excludes $ 5.3 million of contract manufacturer and supplier prepayments, classified as assets held for sale. See Note E: “Assets held for sale” for additional information.
Retirement and Postretirement Plans	Retirement and Postretirement Plans Teradyne recognizes net actuarial gains and losses and the change in the fair value of the plan assets in its operating results in the year in which they occur or upon any interim remeasurement of the plans. Teradyne calculates the expected return on plan assets using the fair value of the plan assets. Actuarial gains and losses are generally measured annually as of December 31 and, accordingly, recorded during the fourth quarter of each year or upon any interim remeasurement of the plans. Teradyne reports net periodic pension cost and net periodic postretirement benefit costs in accordance with ASU 2017-07, “ Compensation—Retirement Benefits (Topic 715): Improving the Presentation of Net Periodic Pension Cost and Net Periodic Postretirement Benefit Cost .” The service cost component of net benefit costs is reported in the same line item in the consolidated statement of operations as other employee compensation costs. The non-service components of net benefit costs such as interest cost, expected return on assets, amortization of prior service cost, and actuarial gains or losses, are reported within other (income) expense, net.
Goodwill, Intangible and Long-Lived Assets	Goodwill, Intangible and Long-Lived Assets Teradyne accounts for goodwill and intangible assets in accordance with ASC 350-10, “ Intangibles-Goodwill and Other. ” Intangible assets are amortized over their estimated useful economic life and are carried at cost less accumulated amortization. Goodwill is assessed for impairment at least annually in the fourth quarter, as of December 31, on a reporting unit basis, or more frequently when events and circumstances occur indicating that the recorded goodwill may be impaired. In accordance with ASC 350-10, Teradyne has the option to perform a qualitative assessment to determine whether it is more likely than not that the fair value of a reporting unit is less than its carrying amount. If Teradyne determines this is the case, Teradyne is required to perform a quantitative goodwill impairment test to identify potential goodwill impairment and measure the amount of goodwill impairment loss to be recognized. If Teradyne determines that it is more likely than not that the fair value of the reporting unit is greater than its carrying amounts, a quantitative goodwill impairment test is not required. In accordance with ASC 360-10, “ Impairment or Disposal of Long-Lived Assets, ” Teradyne reviews long-lived assets for impairment whenever events or changes in business circumstances indicate that the carrying amount of the assets may not be fully recoverable or that the useful lives of these assets are no longer appropriate. Each impairment test is based on a comparison of the estimated undiscounted cash flows to the recorded value of the asset. If impairment is indicated, the asset is written down to its estimated fair value based on a discounted cash flows analysis. The cash flows estimates used to determine the impairment, if any, contain management’s best estimates using appropriate assumptions and projections at that time.
Business Combination	Business Combination Teradyne recognizes the tangible and intangible assets acquired and liabilities assumed based on their estimated fair values at the date of acquisition. The fair value of identifiable intangible assets is based on detailed cash flows valuations that use information and assumptions provided by management. Teradyne estimates the fair value of contingent consideration at the time of the acquisition using all pertinent information known to us at the time to assess the probability of payment of contingent amounts or through the use of a Monte Carlo simulation model. Teradyne allocates any excess purchase price over the fair value of the net tangible and intangible assets acquired and liabilities assumed to goodwill. The assumptions used in the valuations for our acquisitions may differ materially from actual results depending on performance of the acquired businesses and other factors. While Teradyne believes the assumptions used were appropriate, different assumptions in the valuation of assets acquired and liabilities assumed could have a material impact on the timing and extent of impact on our statements of operations. Goodwill is assigned to reporting units as of the date of the related acquisition.
Property, Plant and Equipment	Property, Plant and Equipment Property, plant and equipment are stated at cost and depreciated over the estimated useful lives of the assets. Leasehold improvements and major renewals are capitalized and included in property, plant and equipment accounts, while expenditures for maintenance and repairs and minor renewals are charged to expense. When assets are retired, the assets and related accumulated depreciation are removed from the accounts and any resulting gain or loss is reflected in the consolidated statements of operations. Teradyne provides for depreciation of its assets principally on the straight-line method with the cost of the assets being charged to expense over their useful lives as follows: Buildings 40 years Building improvements 5 to 10 years Leasehold improvements Lesser of lease term or 10 years Furniture and fixtures 10 years Test systems manufactured internally 6 years Machinery, equipment and software 3 to 5 years Test systems manufactured internally are used by Teradyne for customer evaluations and manufacturing and support of its customers. Teradyne depreciates the test systems manufactured internally over a six-year life to cost of revenues, engineering and development, and selling and administrative expenses. Teradyne often sells internally manufactured test equipment to customers. Upon the sale of an internally manufactured test system, the net book value of the system is transferred to inventory and expensed as cost of revenues. The net book value of internally manufactured test systems sold in the years ended December 31, 2023, 2022, and 2021 was $ 2.8 million, $ 6.6 million, and $ 16.6 million, respectively.
Convertible Debt	Convertible Debt Teradyne adopted Accounting Standards Update (“ASU”) ASU 2020-06 – “Debt—Debt with Conversion and Other Options and Derivatives and Hedging—Contracts in Entity’s Own Equity,” on January 1, 2022 using the modified retrospective method of adoption. As a result of adoption, Teradyne recorded an increase of $ 1.4 million to current debt for unsettled shares, an increase of $ 1.8 million to deferred tax assets, an increase of $ 6.6 million to long-term debt for unamortized debt discount, and an increase to retained earnings of $ 94.6 million for the reclassification of the equity component. Mezzanine equity representing unsettled shares value was reduced to zero and additional paid-in capital was reduced by $ 100.8 million. In accordance with ASU 2020-06, Teradyne accounts for a convertible debt instrument as a single liability measured at its amortized cost, as long as no other features require bifurcation and recognition as derivatives. Unsettled shares are recorded in current debt, and there is no recognition of a debt discount, which was previously amortized to interest expense. Settled shares reduce the outstanding debt balance in an amount equal to the cash paid, but do not result in any gain or loss on extinguishment. We use the if-converted method in the diluted EPS calculation for convertible instruments.
Leases	Leases Under ASC 842, a contract is or contains a lease when Teradyne has the right to control the use of an identified asset. Teradyne determines if an arrangement is a lease at inception of the contract, which is the date on which the terms of the contract are agreed to and the agreement creates enforceable rights and obligations. The commencement date of the lease is the date that the lessor makes an underlying asset available for use by Teradyne. As of December 31, 2023, Teradyne does not have material leases that have not yet commenced. Teradyne determines if the lease is an operating or finance lease at the lease commencement date based upon the terms of the lease and the nature of the asset. The lease term used to calculate the lease liability includes options to extend or terminate the lease when it is reasonably certain that the option will be exercised. The lease liability is measured at the present value of future lease payments, discounted using the discount rate for the lease at the commencement date. As Teradyne is typically unable to determine the implicit rate, Teradyne uses an incremental borrowing rate based on the lease term and economic environment at commencement date. Teradyne initially measures payments based on an index by using the applicable rate at lease commencement. Variable payments that do not depend on an index are not included in the lease liability and are recognized as they are incurred. The right-of-use (“ROU”) asset is initially measured as the amount of lease liability, adjusted for any initial lease costs, prepaid lease payments, and reduced by any lease incentives. Teradyne’s contracts often include non-lease components such as common area maintenance. Teradyne elected the practical expedient to account for the lease and non-lease components as a single lease component. For leases with a term of one year or less, Teradyne has elected not to record the lease asset or liability. The lease payments are recognized in the consolidated statement of earnings on a straight-line basis over the lease term. Teradyne includes lease costs within cost of revenues and operating expenses. See Note I: “Leases.”
Engineering and Development Costs	Engineering and Development Costs Teradyne’s products are highly technical in nature and require a large and continuing engineering and development effort. Software development costs incurred prior to the establishment of technological feasibility are charged to expense. Software development costs incurred subsequent to the establishment of technological feasibility are capitalized until the product is available for release to customers. To date, the period between achieving technological feasibility and general availability of the product has been short and software development costs eligible for capitalization have not been material. Engineering and development costs are expensed as incurred and consist primarily of salaries, contractor fees including non-recurring engineering charges related to product design, allocated facility costs, depreciation, and tooling costs.
Stock Compensation Plans and Employee Stock Purchase Plan	Stock Compensation Plans and Employee Stock Purchase Plan Stock-based compensation expense is based on the grant-date fair value estimated in accordance with the provisions of ASC 718-10, “ Compensation-Stock Compensation .” Teradyne elects to account for forfeitures by applying an estimated forfeiture rate and recognizes compensation costs only for those stock-based compensation awards expected to vest. Under its stock compensation plans, Teradyne has granted stock options, restricted stock units and performance-based restricted stock units, and employees are eligible to purchase Teradyne’s common stock through its Employee Stock Purchase Plan (“ESPP”). Excess tax benefits or tax deficiencies are recognized as a discrete tax benefit or discrete tax expense to the current income tax provision in Teradyne’s consolidated statements of operations, all excess tax benefits related to share-based payments are reported as cash flows from operating activities, and all cash payments made to taxing authorities on the employees’ behalf for withheld shares are presented as financing activities on the statement of cash flows.
Income Taxes	Income Taxes Deferred tax assets and liabilities are determined based on differences between financial reporting and tax basis of assets and liabilities and are measured using the enacted tax rates and laws that will be in effect when the differences are expected to reverse. The measurement of deferred tax assets is reduced by a valuation allowance if it is more likely than not that some or all of the deferred tax assets will not be realized. Teradyne performed the required assessment of positive and negative evidence regarding the realization of the net deferred tax assets in accordance with ASC 740, “Accounting for Income Taxes.” This assessment included the evaluation of scheduled reversals of deferred tax liabilities, estimates of projected future taxable income and tax-planning strategies. Although realization is not assured, based on its assessment, Teradyne concluded that it is more likely than not that such assets, net of the existing valuation allowance, will be realized.
Advertising Costs	Advertising Costs Teradyne expenses all advertising costs as incurred. Advertising costs were $ 15.5 million, $ 17.3 million and $ 13.4 million in 2023, 2022 and 2021 , respectively.
Translation of Non-U.S. Currencies	Translation of Non-U.S. Currencies The functional currency for all non-U.S. subsidiaries is the U.S. dollar, except for Universal Robots, MiR and Lemsys for which the local currency is its functional currency. All foreign currency denominated monetary assets and liabilities are remeasured on a monthly basis into the functional currency using exchange rates in effect at the end of the period. All foreign currency denominated non-monetary assets and liabilities are remeasured into the functional currency using historical exchange rates. Net foreign exchange gains and losses resulting from remeasurement are included in other (income) expense, net. For Universal Robots, MiR and Lemsys, assets and liabilities are translated into U.S. dollars using exchange rates in effect at the end of the period. Revenues and expense amounts are translated using an average of exchange rates in effect during the period. Translation adjustments are recorded within accumulated other comprehensive income (loss) on the balance sheet. Net foreign exchange gains and losses resulting from remeasurement are included in other (income) expense, net. For the years ended December 31, 2023, 2022 and 2021 , losses (gains) from the remeasurement of the monetary assets and liabilities denominated in foreign currencies were $ 10.9 million, $ 10.8 million, and $( 2.1 ) million, respectively. These amounts do not reflect the corresponding (gains) losses from foreign exchange contracts. See Note H: “Financial Instruments” regarding foreign exchange contracts.
Net Income per Common Share	Net Income per Common Share Basic net income per common share is calculated by dividing net income by the weighted average number of common shares outstanding during the period. Except where the result would be anti-dilutive, diluted net income per common share is calculated by dividing net income by the sum of the weighted average number of common shares plus common stock equivalents, if applicable. With respect to its convertible debt issued in 2016, Teradyne is required to settle the principal of the convertible debt in cash; accordingly, the principal amount is excluded from the determination of diluted earnings per share. As a result, Teradyne is accounting for the conversion spread using the treasury stock method.
Comprehensive Income	Comprehensive Income Comprehensive income includes net income, unrealized pension and postretirement prior service costs and benefits, unrealized gains and losses on investments in debt marketable securities, unrealized gains and losses on cash flow hedge and foreign currency translation adjustment.

Accounting Policies (Tables)

Accounting Policies (Tables)	12 Months Ended
	Dec. 31, 2023
Accounting Policies [Abstract]
Deferred Revenue and Customer Advances	As of December 31, 2023 and 2022, deferred revenue and customer advances consisted of the following and are included in the short and long-term deferred revenue and customer advances: 2023 2022 (in thousands) Maintenance, service and training $ 66,458 $ 78,089 Customer advances, undelivered elements and other 35,731 59,147 Extended warranty 34,897 56,180 Total deferred revenue and customer advances $ 137,086 $ 193,416
Other Accrued Liabilities	Amount (in thousands) Balance at December 31, 2020 $ 16,633 Accruals for warranties issued during the period 35,727 Accruals related to pre-existing warranties ( 6,846 ) Settlements made during the period ( 20,937 ) Balance at December 31, 2021 24,577 Accruals for warranties issued during the period 21,851 Accruals related to pre-existing warranties ( 5,618 ) Settlements made during the period ( 26,629 ) Balance at December 31, 2022 14,181 Accruals for warranties issued during the period 21,644 Accruals related to pre-existing warranties ( 1,576 ) Settlements made during the period ( 18,551 ) Balance at December 31, 2023 $ 15,698
Extended Product Warranty of Short and Long-Term Deferred Revenue and Customer Advances	Amount (in thousands) Balance at December 31, 2020 $ 51,929 Deferral of new extended warranty revenue 43,597 Recognition of extended warranty deferred revenue ( 31,358 ) Balance at December 31, 2021 64,168 Deferral of new extended warranty revenue 33,686 Recognition of extended warranty deferred revenue ( 41,674 ) Balance at December 31, 2022 56,180 Deferral of new extended warranty revenue 14,330 Recognition of extended warranty deferred revenue ( 35,613 ) Balance at December 31, 2023 $ 34,897
Summary of Deferred Costs, Capitalized, Prepaid, and Other Assets Disclosure	Prepayments consist of the following: 2023 (1) 2022 (in thousands) Contract manufacturer and supplier prepayments $ 502,257 $ 491,105 Prepaid maintenance and other services 17,592 14,545 Prepaid taxes 16,083 18,625 Other prepayments 13,038 8,687 Total prepayments $ 548,970 $ 532,962 (1) Excludes $ 5.3 million of contract manufacturer and supplier prepayments, classified as assets held for sale. See Note E: “Assets held for sale” for additional information.
Useful Lives of Assets	Teradyne provides for depreciation of its assets principally on the straight-line method with the cost of the assets being charged to expense over their useful lives as follows: Buildings 40 years Building improvements 5 to 10 years Leasehold improvements Lesser of lease term or 10 years Furniture and fixtures 10 years Test systems manufactured internally 6 years Machinery, equipment and software 3 to 5 years

Revenue (Tables)

Revenue (Tables)	12 Months Ended
	Dec. 31, 2023
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 Robotics System-on-a-chip Memory System Universal Robots Mobile Industrial Robots Wireless Corporate Total (in thousands) For the Year Ended December 31, 2023 (1) Timing of Revenue Recognition Point in Time $ 1,141,882 $ 356,417 $ 268,379 $ 296,252 $ 66,986 $ 129,399 $ — $ 2,259,315 Over Time 290,739 29,598 69,818 7,540 4,405 14,883 — 416,983 Total $ 1,432,621 $ 386,015 $ 338,197 $ 303,792 $ 71,391 $ 144,282 $ — $ 2,676,298 Geographical Market Asia Pacific $ 1,214,322 $ 366,151 $ 153,387 $ 63,312 $ 10,424 $ 85,415 $ — $ 1,893,011 Americas 117,728 11,367 151,579 111,761 36,191 50,770 — 479,396 Europe, Middle East and Africa 100,571 8,497 33,231 128,719 24,776 8,097 — 303,891 Total $ 1,432,621 $ 386,015 $ 338,197 $ 303,792 $ 71,391 $ 144,282 $ — $ 2,676,298 For the Year Ended December 31, 2022 (1) Timing of Revenue Recognition Point in Time $ 1,445,238 $ 344,693 $ 402,074 $ 317,514 $ 73,812 $ 189,040 $ 251 $ 2,772,622 Over Time 261,646 29,013 67,272 8,218 3,594 12,680 — 382,423 Total $ 1,706,884 $ 373,706 $ 469,346 $ 325,732 $ 77,406 $ 201,720 $ 251 $ 3,155,045 Geographical Market Asia Pacific $ 1,514,964 $ 360,176 $ 294,350 $ 73,930 $ 15,724 $ 140,767 $ — $ 2,399,911 Americas 122,575 11,987 146,040 112,203 35,213 47,350 251 475,619 Europe, Middle East and Africa 69,345 1,543 28,956 139,599 26,469 13,603 — 279,515 Total $ 1,706,884 $ 373,706 $ 469,346 $ 325,732 $ 77,406 $ 201,720 $ 251 $ 3,155,045 For the Year Ended December 31, 2021 (1) Timing of Revenue Recognition Point in Time $ 1,989,979 $ 365,441 $ 409,383 $ 305,512 $ 60,884 $ 204,247 $ — $ 3,335,446 Over Time 256,751 30,171 58,356 5,670 3,839 12,648 — 367,435 Total $ 2,246,730 $ 395,612 $ 467,739 $ 311,182 $ 64,723 $ 216,895 $ — $ 3,702,881 Geographical Market Asia Pacific $ 2,076,647 $ 381,444 $ 306,812 $ 81,456 $ 12,919 $ 172,103 $ — $ 3,031,381 Americas 102,702 10,665 135,230 94,897 26,069 36,173 — 405,736 Europe, Middle East and Africa 67,381 3,503 25,697 134,829 25,735 8,619 — 265,764 Total $ 2,246,730 $ 395,612 $ 467,739 $ 311,182 $ 64,723 $ 216,895 $ — $ 3,702,881 (1) Includes $ 5.2 m illion, $ 8.2 million and $ 13.2 million in 2023, 2022 and 2021, respectively, for leases of Teradyne’s systems recognized outside of ASC 606: “Revenue from Contracts with Customers.”

Assets Held for Sale (Tables)

Assets Held for Sale (Tables)	12 Months Ended
	Dec. 31, 2023
Discontinued Operations and Disposal Groups [Abstract]
Schedule of Assets Held-for-sale	Assets held-for-sale comprise of the following as of December 31, 2023: December 31, 2023 (in thousands) 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

Inventories (Tables)

Inventories (Tables)	12 Months Ended
	Dec. 31, 2023
Inventory Disclosure [Abstract]
Composition of Inventories, Net	Inventories, net consisted of the following at December 31, 2023 and 2022: 2023 (1) 2022 (in thousands) Raw material $ 258,422 $ 256,065 Work-in-process 26,851 37,982 Finished goods 24,701 30,972 $ 309,974 $ 325,019 (1) Excludes $ 18.0 million of primarily work-in-process inventories, net classified as assets held for sale. See Note E: “Assets held for sale” for additional information.

Property, Plant and Equipment (

Property, Plant and Equipment (Tables)	12 Months Ended
	Dec. 31, 2023
Property, Plant and Equipment [Abstract]
Property Plant and Equipment, Net	Property, plant and equipment, net consisted of the following at December 31, 2023 and 2022: 2023 (1) 2022 (in thousands) Land $ 19,487 $ 18,481 Buildings 127,705 128,991 Machinery, equipment and software 1,047,235 1,059,880 Furniture and fixtures 28,093 29,929 Leasehold improvements 66,777 64,631 Construction in progress 54,799 22,470 1,344,096 1,324,382 Less: accumulated depreciation 898,604 905,699 $ 445,492 $ 418,683 (1) Excludes $ 9.0 million of property, plant and equipment, net classified as assets held for sale. See Note E: “Assets held for sale” for additional information.

Financial Instruments (Tables)

Financial Instruments (Tables)	12 Months Ended
	Dec. 31, 2023
Fair Value Disclosures [Abstract]
Schedule of Fair Value of Financial Assets and Liabilities Measured on Recurring Basis	The following table sets forth by fair value hierarchy Teradyne’s financial assets and liabilities that were measured at fair value on a recurring basis as of December 31, 2023 and 2022 : 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 Commercial paper — 1,667 — 1,667 Debt mutual funds 8,773 — — 8,773 U.S. government agency securities — 4,892 — 4,892 Certificates of deposit and time deposits — 21,772 — 21,772 Non-U.S. government securities — 810 — 810 Equity securities: Mutual funds 47,132 — — 47,132 Total $ 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 December 31, 2022 Quoted Prices Significant Significant Total (in thousands) Assets Cash $ 632,417 $ — $ — $ 632,417 Cash equivalents 161,767 60,589 — 222,356 Available for sale securities: Corporate debt securities — 50,856 — 50,856 U.S. Treasury securities — 39,649 — 39,649 Commercial paper — 7,159 — 7,159 Debt mutual funds 6,580 — — 6,580 U.S. government agency securities — 6,352 — 6,352 Certificates of deposit and time deposits — 1,740 — 1,740 Non-U.S. government securities — 535 — 535 Equity securities: Mutual funds 37,518 — — 37,518 Total $ 838,282 $ 166,880 $ — $ 1,005,162 Derivative assets — 86 — 86 Total $ 838,282 $ 166,966 $ — $ 1,005,248 Liabilities Derivative liabilities — 4,215 — 4,215 Total $ — $ 4,215 $ — $ 4,215 Reported as follows: (Level 1) (Level 2) (Level 3) Total (in thousands) Assets Cash and cash equivalents $ 794,184 $ 60,589 $ — $ 854,773 Marketable securities — 39,612 — 39,612 Long-term marketable securities 44,098 66,679 — 110,777 Other current assets — 86 — 86 Total $ 838,282 $ 166,966 $ — $ 1,005,248 Liabilities Other current liabilities $ — $ 4,215 $ — $ 4,215 Total $ — $ 4,215 $ — $ 4,215
Schedule of Carrying Amounts and Fair Values of Financial Instruments	The carrying amounts and fair values of Teradyne’s financial instruments at December 31, 2023 and 2022 were as follows: December 31, 2023 December 31, 2022 Carrying Value Fair Value Carrying Value Fair Value (in thousands) Assets Cash and cash equivalents $ 757,571 $ 757,571 $ 854,773 $ 854,773 Marketable securities 179,588 179,588 150,389 150,389 Derivative assets 18,746 18,746 86 86 Liabilities Derivative liabilities 2,545 2,545 4,215 4,215 Convertible debt (1) — — 50,115 139,007 (1) The carrying value represents the bifurcated debt component only, while the fair value is based on quoted market prices for the convertible note which includes the equity conversion features.
Schedule of Available-for-Sale Marketable Securities	The following tables summarize the composition of available-for-sale marketable securities at December 31, 2023 and 2022: December 31, 2023 Available-for-Sale Cost Unrealized Unrealized Fair Market 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 Market 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 December 31, 2022 Available-for-Sale Cost Unrealized Unrealized Fair Market Fair Market (in thousands) Corporate debt securities $ 57,006 $ 3 $ ( 6,153 ) $ 50,856 $ 50,667 U.S. Treasury securities 44,030 — ( 4,381 ) 39,649 39,649 Commercial paper 7,089 70 — 7,159 — Debt mutual funds 6,997 — ( 417 ) 6,580 3,095 U.S. government agency securities 6,442 — ( 90 ) 6,352 6,352 Certificates of deposit and time deposits 1,740 — — 1,740 — Non-U.S. government securities 535 — — 535 — $ 123,839 $ 73 $ ( 11,041 ) $ 112,871 $ 99,763 Reported as follows: Cost Unrealized Unrealized Fair Market Fair Market (in thousands) Marketable securities $ 39,950 $ 70 $ ( 408 ) $ 39,612 $ 30,713 Long-term marketable securities 83,889 3 ( 10,633 ) $ 73,259 69,050 $ 123,839 $ 73 $ ( 11,041 ) $ 112,871 $ 99,763
Contractual Maturities of Investments Held	The contractual maturities of investments in available-for-sale marketable securities held at December 31, 2023 were as follows: Cost Fair Value (in thousands) Due within one year $ 62,385 $ 62,154 Due after 1 year through 5 years 23,703 23,319 Due after 5 years through 10 years 6,049 5,735 Due after 10 years 39,159 32,475 Total $ 131,296 $ 123,683
Schedule of Notional Amount of Derivatives	At December 31, 2023 and 2022, to hedge certain of its local currency balance sheet assets and liabilities, 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 December 31, December 31, 2022 (in millions) Currency Hedged (Buy/Sell) U.S. dollar/Taiwan dollar $ 42.7 $ 29.2 U.S. dollar/Danish krone 36.0 — U.S. dollar/Japanese yen 11.0 37.1 U.S. dollar/Korean won 7.2 6.4 U.S. dollar/British pound sterling 1.5 1.2 Euro/U.S. dollar 25.3 38.4 Singapore dollar/U.S. dollar 16.6 33.5 Philippine peso/U.S. dollar 10.1 2.7 Chinese yuan/U.S. dollar 1.0 2.2 Danish krone/U.S. dollar 0.7 — Total 152.1 150.7
Schedule of Foreign Currency Cash Flow Hedges	At December 31, 2023 and 2022, 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 December 31, December 31, 2022 (in millions) Currency Hedged (Buy/Sell) U.S. dollar/Japanese yen $ 35.5 $ 61.2 U.S. dollar/Taiwan dollar — 10.9 Japanese yen/U.S. dollar — 23.4 Taiwan dollar/U.S. dollar — 5.5 Total $ 35.5 $ 101.0
Schedule of Derivative Instruments in Statement of Financial Position at Fair Value	he following table summarizes the fair value of derivative instruments as of December 31, 2023 and 2022: Balance Sheet Location December 31, December 31, (in thousands) Derivatives not designated as hedging instruments: Foreign exchange forward contracts Other current assets $ 733 $ 86 Foreign exchange option contracts Other current assets 17,364 — Foreign exchange forward contracts Other current liabilities ( 2,545 ) ( 990 ) Derivatives designated as hedging instruments: Foreign exchange forward contracts Other current assets 648 — Foreign exchange option contracts Other current liabilities — ( 3,225 ) Total derivatives $ 16,200 $ ( 4,129 )
Schedule of Effect of Derivative Instruments on Statement of Operations Recognized	The following table summarizes the effect of derivative instruments in the statements of operations recognized for the years ended December 31, 2023, 2022, and 2021: Location of (Gains) Losses December 31, December 31, December 31, (in thousands) Derivatives not designated as hedging instruments: Foreign exchange forward contracts (1) Other (income) expense, net $ ( 1,843 ) $ ( 2,482 ) $ 6,488 Foreign exchange option contracts Other (income) expense, net ( 7,464 ) — — Derivatives designated as hedging instruments: Foreign exchange forward and option contracts Revenue ( 3,127 ) ( 251 ) — Total derivatives $ ( 12,434 ) $ ( 2,733 ) $ 6,488 (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 years ended December 31, 2023, 2022 and 2021 , net losses (gains) from remeasurement of monetary assets and liabilities denominated in foreign currencies were $ 10.9 million, $ 10.8 million, and $( 2.1 ) million, respectively.

Leases (Tables)

Leases (Tables)	12 Months Ended
	Dec. 31, 2023
Leases, Operating [Abstract]
Supplemental cash flow information related to leases	Supplemental cash flows information related to leases was as follows: For the Years Ended December 31, December 31, December 31, (in thousands) Cash paid for amounts included in the measurement of lease $ 26,059 $ 20,775 $ 24,593 Right-of-use assets obtained in exchange for new lease obligations 17,987 26,149 34,246
Schedule of operating lease, maturity	Maturities of lease liabilities as of December 31, 2023 were as follows: Operating Lease (1) (in thousands) 2024 $ 21,045 2025 18,755 2026 15,074 2027 11,733 2028 7,622 Thereafter 23,906 Total lease payments 98,135 Less imputed interest ( 15,521 ) Total lease liabilities $ 82,614 (1) Excludes $ 2.5 million of lease liabilities classified as liabilities held for sale. See Note E: “Assets held for sale” for additional information.

Debt (Tables)

Debt (Tables)	12 Months Ended
	Dec. 31, 2023
Debt Disclosure [Abstract]
Components of Convertible Senior Notes	The below tables represent the key components of Teradyne’s convertible senior notes: For the Years Ended December 31, December 31, (in thousands) Debt principal $ — $ 50,228 Unamortized debt issuance fees — 113 Net carrying amount of convertible debt $ — $ 50,115 For the Years Ended December 31, December 31, (in thousands) Contractual interest expense on the coupon $ 312 $ 732 Amortization of the issuance fees recognized as interest expense 113 209 Total interest expense on the convertible debt $ 425 $ 941

Accumulated Other Comprehensi_2

Accumulated Other Comprehensive Income (Loss) (Tables)	12 Months Ended
	Dec. 31, 2023
Equity [Abstract]
Changes in Accumulated Other Comprehensive Income (Loss)	Changes in accumulated other comprehensive income (loss), which is presented net of tax, consist of the following: Foreign Unrealized Unrealized (Losses) Gains on Retirement Total (in thousands) Balance at December 31, 2021, net of tax of $ 0 , $ 1,055 , $ 0 , 1,128 ), respectively $ ( 10,818 ) $ 3,704 $ — $ 1,166 $ ( 5,948 ) Other comprehensive loss before reclassifications, net of tax of 0 , $( 3,388 ), $( 708 ), $ 0 , respectively ( 29,031 ) ( 12,666 ) ( 2,517 ) — ( 44,214 ) Amounts reclassified from accumulated other comprehensive 0 , $ 25 , $ 0 , $( 2 ), respectively — 301 — ( 7 ) 294 Net current period other comprehensive loss, net of tax of $ 0 , 3,363 ), $( 708 ), $( 2 ), respectively ( 29,031 ) ( 12,365 ) ( 2,517 ) ( 7 ) ( 43,920 ) 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 gain before reclassifications, net of tax of 0 , $ 568 , $ 1,537 , $ 0 , respectively 17,407 2,423 5,464 — 25,294 Amounts reclassified from accumulated other comprehensive 0 , $ 12 , $( 686 ), $( 2 ), — 44 ( 2,441 ) ( 7 ) ( 2,404 ) Net current period other comprehensive gain (loss), net of tax 0 $ 580 , $ 851 , $( 2 ), respectively 17,407 2,467 3,023 ( 7 ) 22,890 Balance at December 31, 2023, net of tax of $ 0 , $( 1,728 ), $ 143 , 1,132 ), respectively $ ( 22,442 ) $ ( 6,194 ) $ 506 $ 1,152 $ ( 26,978 )
Reclassifications Out of Accumulated Other Comprehensive Income (Loss) to Statements of Operations	Reclassifications out of accumulated other comprehensive income (loss) to the statements of operations for the years ended December 31, 2023, 2022, and 2021, were as follows: Details about Accumulate Other Comprehensive Income (Loss) Components For the years ended Affected Line Item December 31, December 31, December 31, (in thousands) Available-for-sale marketable securities Unrealized (losses) gains, net of tax of $( 12 ), $( 25 ), $ 277 , $ ( 44 ) $ ( 301 ) $ 995 Other (income) expense, net Cash flow hedges: Unrealized gains, net of tax of $ 686 , $ 0 , $ 0 , respectively 2,441 — — Revenue Defined benefit pension and postretirement plans: Amortization of prior service benefit, net of tax of $ 2 , $ 2 , $ 2 , 7 7 7 (a) Total reclassifications, net of tax of $ 676 , $( 23 ), $ 279 , respectively $ 2,404 $ ( 294 ) $ 1,002 Net income (a) The amortization of prior service credit is included in the computation of net periodic pension cost and postretirement benefit; see Note P: “Retirement Plans.”

Goodwill and Intangible Assets

Goodwill and Intangible Assets (Tables)	12 Months Ended
	Dec. 31, 2023
Goodwill and Intangible Assets Disclosure [Abstract]
Changes in Carrying Amount of Goodwill by Segment	The changes in the carrying amount of goodwill by reportable segments for the years ended December 31, 2023 and 2022 are as follows: Robotics Wireless Semiconductor System Total (in thousands) Balance at December 31, 2021: Goodwill $ 405,971 $ 361,819 $ 262,101 $ 158,699 $ 1,188,590 Accumulated impairment losses — ( 353,843 ) ( 260,540 ) ( 148,183 ) ( 762,566 ) 405,971 7,976 1,561 10,516 426,024 Foreign currency translation adjustment ( 22,805 ) — ( 24 ) — ( 22,829 ) Balance at December 31, 2022: Goodwill 383,166 361,819 262,077 158,699 1,165,761 Accumulated impairment losses — ( 353,843 ) ( 260,540 ) ( 148,183 ) ( 762,566 ) 383,166 7,976 1,537 10,516 403,195 Foreign currency translation adjustment 12,297 — 160 — 12,457 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 ) $ 395,463 $ 7,976 $ 1,697 $ 10,516 $ 415,652
Schedule of Amortizable Intangible Assets	Amortizable intangible assets consist of the following and are included in intangible assets, net on the balance sheets: December 31, 2023 Gross Accumulated Foreign Currency Translation Adjustment Net (in thousands) 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 December 31, 2022 Gross Accumulated Foreign Currency Translation Adjustment Net (in thousands) Developed technology $ 270,967 $ ( 234,208 ) $ ( 5,935 ) $ 30,824 Customer relationships 57,739 ( 51,186 ) 172 6,725 Tradenames and trademarks 59,387 ( 41,930 ) ( 1,528 ) 15,929 Total intangible assets $ 388,093 $ ( 327,324 ) $ ( 7,291 ) $ 53,478 (1) In 2023 and 2022 , $ 9.3 million and $ 1.6 million, respectively, of amortizable intangible assets became fully amortized and have been eliminated from the gross carrying amount and accumulated amortization.
Schedule of Estimated Intangible Assets Amortization Expense	Estimated intangible assets amortization expense for each of the five succeeding fiscal years is as follows: Year Amortization Expense (in thousands) 2024 $ 18,983 2025 11,402 2026 2,390 2027 1,173 2028 1,092 Thereafter 364

Net Income Per Common Share (Ta

Net Income Per Common Share (Tables)	12 Months Ended
	Dec. 31, 2023
Earnings Per Share [Abstract]
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: 2023 2022 2021 (in thousands, except per share amounts) Net income for basic and diluted net income per share $ 448,752 $ 715,501 $ 1,014,589 Weighted average common shares-basic 154,310 158,434 164,960 Effect of dilutive potential common shares: Convertible note hedge warrant shares (1) 8,897 8,806 9,956 Incremental shares from assumed conversion of convertible notes (2) 633 1,763 7,435 Restricted stock units 423 657 1,180 Stock options 34 52 86 Employee stock purchase rights 7 22 8 Dilutive potential common shares 9,994 11,300 18,665 Weighted average common shares-diluted 164,304 169,734 183,625 Net income per common share-basic $ 2.91 $ 4.52 $ 6.15 Net income per common share-diluted $ 2.73 $ 4.22 $ 5.53 (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 the assumed conversion of the convertible notes was 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 debt, was divided by the average Teradyne stock price for the period.

Retirement Plans (Tables)

Retirement Plans (Tables)	12 Months Ended
	Dec. 31, 2023
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Pension and Postretirement Benefit Plan Assets and Obligations	The December 31 balances of these defined benefit pension plans assets and obligations are shown below: 2023 2022 United States Foreign United States Foreign (in thousands) Assets and Obligations Change in benefit obligation: Projected benefit obligation: Beginning of year $ 143,814 $ 29,935 $ 192,472 $ 45,774 Service cost 1,063 446 1,588 784 Interest cost 6,888 1,057 4,886 482 Actuarial loss (gain) 3,229 2,738 ( 45,932 ) ( 13,181 ) Benefits paid ( 10,807 ) ( 947 ) ( 9,200 ) ( 863 ) Liability (gain) loss due to settlement — ( 254 ) — — Non-U.S. currency movement — 1,009 — ( 3,061 ) End of year 144,187 33,984 143,814 29,935 Change in plan assets: Fair value of plan assets: Beginning of year 111,760 2,087 149,578 2,017 Actual return on plan assets 8,613 43 ( 31,835 ) 153 Company contributions 3,051 1,028 3,217 949 Benefits paid ( 10,807 ) ( 947 ) ( 9,200 ) ( 863 ) Settlements gain — ( 254 ) — — Non-U.S. currency movement — ( 28 ) — ( 169 ) End of year 112,617 1,929 111,760 2,087 Funded status $ ( 31,570 ) $ ( 32,055 ) $ ( 32,054 ) $ ( 27,848 )
Amounts Recorded within Statement of Financial Position	The following table provides amounts recorded within the account line items of the statements of financial position as of December 31: 2023 2022 United States Foreign United States Foreign (in thousands) Retirement plans assets $ 11,504 $ — $ 11,761 $ — Accrued employees’ compensation and withholdings ( 3,110 ) ( 1,255 ) ( 3,055 ) ( 1,191 ) Retirement plans liabilities ( 39,964 ) ( 30,800 ) ( 40,760 ) ( 26,657 ) Funded status $ ( 31,570 ) $ ( 32,055 ) $ ( 32,054 ) $ ( 27,848 )
Pension Plans with Accumulated Benefit Obligation and Projected Benefit Obligation in Excess of Plan Assets	Information for pension plans with an accumulated benefit obligation in excess of plan assets as of December 31: 2023 2022 United States Foreign United States Foreign (in millions) Projected benefit obligation $ 43.1 $ 34.0 $ 43.8 $ 29.9 Accumulated benefit obligation 42.6 32.5 42.3 28.6 Fair value of plan assets — 1.9 — 2.1
Net Periodic Pension and Postretirement Benefit Cost (Income)	For the years ended December 31, 2023, 2022, and 2021, Teradyne’s net periodic pension cost (income) was comprised of the following: 2023 2022 2021 United Foreign United Foreign United Foreign (in thousands) Components of Net Periodic Pension Cost (Income): Service cost $ 1,063 $ 446 $ 1,588 $ 784 $ 1,784 $ 941 Interest cost 6,888 1,057 4,886 482 4,427 337 Expected return on plan assets ( 5,194 ) ( 45 ) ( 2,927 ) ( 75 ) ( 3,858 ) ( 67 ) Net actuarial loss (gain) 18 2,735 ( 11,170 ) ( 13,259 ) 643 ( 2,223 ) Settlement (gain) loss ( 209 ) 5 — — ( 204 ) — Total net periodic pension cost (income) $ 2,566 $ 4,198 $ ( 7,623 ) $ ( 12,068 ) $ 2,792 $ ( 1,012 )
Weighted Average Assumptions to Determine Net Periodic Cost and Benefit Obligation	Weighted Average Assumptions to Determine Net Periodic Pension Cost at January 1: 2023 2022 2021 United Foreign United Foreign United Foreign Discount rate 3.5 % 3.5 % 2.5 % 1.1 % 2.2 % 0.7 % Expected return on plan assets 4.8 1.8 2.0 4.0 2.4 3.5 Salary progression rate 2.4 2.1 2.4 2.2 2.4 2.3 Weighted Average Assumptions to Determine Pension Obligations at December 31: 2023 2022 United States Foreign United States Foreign Discount rate 4.7 % 3.0 % 4.9 % 3.5 % Salary progression rate 2.5 2.4 2.5 2.1
Weighted Average Pension Asset Allocations by Category	The following table provides weighted average pension asset allocation by asset category at December 31, 2023 and 2022: 2023 2022 United States Foreign United States Foreign Fixed income securities 94.0 % — % 94.0 % — % Equity securities 5.0 — 5.0 — Other 1.0 100.0 1.0 100.0 100.0 % 100.0 % 100.0 % 100.0 %
Target Asset Allocation and Index for Each Asset Category	The target asset allocation and the index for each asset category for the U.S. Plan, per the investment policy, are as follows: Asset Category: Policy Index: Target U.S. corporate fixed income Bloomberg U.S. Corporate A or Better Index, 20+ Year Index 43 % U.S. corporate fixed income Bloomberg U.S. Corporate A or Better Index, 5 - 20 Year Index 32 U.S. government fixed income Bloomberg U.S. 3 - 10 year Treasury Bond Index 14 Global equity MSCI World Index 5 High yield fixed income ICE BofA BB-B U.S. High Yield Constrained Index 5 Cash ICE BofA 3 -Month Treasury Bill Index 1
Changes in Fair Value of Pension Assets	The fair value of pension plan assets by asset category and by level at December 31, 2023 and December 31, 2022 were as follows: December 31, 2023 United States Foreign Level 1 Level 2 Level 3 Total Level 1 Level 2 Level 3 Total (in thousands) Fixed income securities: Corporate debt securities $ — $ 89,971 $ — $ 89,971 $ — $ — $ — $ — U.S. government securities — 15,817 — 15,817 — — — — Global equity — 5,691 — 5,691 — — — — Other — — — — — 1,929 — 1,929 Cash and cash equivalents 1,138 — — 1,138 — — — — Total $ 1,138 $ 111,479 $ — $ 112,617 $ — $ 1,929 $ — $ 1,929 December 31, 2022 United States Foreign Level 1 Level 2 Level 3 Total Level 1 Level 2 Level 3 Total (in thousands) Fixed income securities: Corporate debt securities $ — $ 89,403 $ — $ 89,403 $ — $ — $ — $ — U.S. government securities — 15,631 — 15,631 — — — — Global equity — 5,579 — 5,579 — — — — Other — — — — — 2,087 — 2,087 Cash and cash equivalents 1,147 — — 1,147 — — — — Total $ 1,147 $ 110,613 $ — $ 111,760 $ — $ 2,087 $ — $ 2,087
Expected Future Benefit Payments	Future benefit payments are expected to be paid as follows: United States Foreign (in thousands) 2024 $ 10,210 $ 1,312 2025 9,720 1,068 2026 9,863 1,191 2027 10,792 1,301 2028 10,795 1,238 2029-2032 51,857 8,832
Postretirement Benefit Plans
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Pension and Postretirement Benefit Plan Assets and Obligations	The December 31 balances of the postretirement assets and obligations are shown below: 2023 2022 (in thousands) Assets and Obligations Change in benefit obligation: Projected benefit obligation: Beginning of year $ 5,345 $ 7,210 Service cost 34 64 Interest cost 299 177 Actuarial loss (gain) 155 ( 1,155 ) Benefits paid ( 1,413 ) ( 950 ) Special termination benefits 2,513 — End of year 6,933 5,345 Change in plan assets: Fair value of plan assets: Beginning of year — — Company contributions 1,413 950 Benefits paid ( 1,413 ) ( 950 ) End of year — — Funded status $ ( 6,933 ) $ ( 5,345 )
Amounts Recorded within Statement of Financial Position	The following table provides amounts recorded within the account line items of financial position as of December 31: 2023 2022 (in thousands) Accrued employees’ compensation and withholdings $ ( 1,508 ) $ ( 853 ) Retirement plans liabilities ( 5,425 ) ( 4,492 ) Funded status $ ( 6,933 ) $ ( 5,345 )
Amounts Recognized in Accumulated Other Comprehensive Income (loss)	The following table provides amounts recognized in accumulated other comprehensive income (loss) as of December 31: 2023 2022 (in thousands) Prior service credit, before tax $ ( 23 ) $ ( 31 ) Deferred taxes ( 1,691 ) ( 1,689 ) Total recognized in other comprehensive income (loss), net of tax $ ( 1,714 ) $ ( 1,720 )
Net Periodic Pension and Postretirement Benefit Cost (Income)	For the years ended December 31, 2023, 2022, and 2021, Teradyne’s net periodic postretirement benefit cost (income) was comprised of the following: 2023 2022 2021 (in thousands) Components of Net Periodic Postretirement Benefit Cost (income): Service cost $ 34 $ 64 $ 64 Interest cost 299 177 170 Amortization of prior service credit ( 9 ) ( 9 ) ( 9 ) Net actuarial loss (gain) 155 ( 1,155 ) ( 433 ) Special termination benefits 2,513 — — Total net periodic postretirement benefit cost (income) 2,992 ( 923 ) ( 208 ) Changes in Plan Assets and Benefit Obligations Recognized in Other Reversal of amortization items: Prior service credit 9 9 9 Total recognized in other comprehensive income 9 9 9 Total recognized in net periodic postretirement cost (income) and other $ 3,001 $ ( 914 ) $ ( 199 )
Weighted Average Assumptions to Determine Net Periodic Cost and Benefit Obligation	Weighted Average Assumptions to Determine Net Periodic Postretirement Benefit Income as of January 1: 2023 2022 2021 Discount rate 5.0 % 2.6 % 2.2 % Initial health care cost trend rate 7.2 7.3 7.3 Ultimate health care cost trend rate 4.5 4.5 4.5 Year in which ultimate health care cost trend rate is reached 2032 2029 2029 Weighted Average Assumptions to Determine Postretirement Benefit Obligation as of December 31: 2023 2022 2021 Discount rate 4.7 % 5.0 % 2.6 % Initial health care trend 7.7 7.2 7.3 Ultimate health care trend 4.5 4.5 4.5 Medical cost trend rate decrease to ultimate rate in year 2033 2032 2029
Expected Future Benefit Payments	Future benefit payments are expected to be paid as follows: Benefit Payments (in thousands) 2024 $ 1,508 2025 924 2026 701 2027 637 2028 568 2029-2032 2,004

Stock-Based Compensation (Table

Stock-Based Compensation (Tables)	12 Months Ended
	Dec. 31, 2023
Share-Based Payment Arrangement [Abstract]
Schedule of Estimated Fair Value of TSR Performance-Based Restricted Stock Unit Awards Assumptions	The fair value was estimated using the Monte Carlo simulation model with the following assumptions: 2023 2022 2021 Risk-free interest rate 4.0 % 1.4 % 0.2 % Teradyne volatility-historical 49.7 % 47.1 % 43.9 % NYSE Composite Index volatility-historical 24.1 % 22.7 % 22.9 % Dividend yield 0.4 % 0.4 % 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: 2023 2022 2021 Expected life (years) 4.0 4.0 5.0 Risk-free interest rate 3.8 % 1.6 % 0.4 % Volatility-historical 46.6 % 43.7 % 37.8 % Dividend yield 0.4 % 0.4 % 0.4 %
Stock Compensation Plan Activity	Stock compensation plan activity for the years 2023, 2022 and 2021, is as follows: 2023 2022 2021 (in thousands) Restricted Stock Units: Non-vested at January 1 1,317 1,417 1,789 Awarded 728 660 447 Vested ( 609 ) ( 709 ) ( 749 ) Forfeited ( 58 ) ( 51 ) ( 70 ) Non-vested at December 31 1,378 1,317 1,417 Stock Options: Outstanding at January 1 188 171 216 Granted 41 42 34 Exercised ( 56 ) ( 25 ) ( 78 ) Forfeited ( 2 ) — ( 1 ) Expired — — — Outstanding at December 31 171 188 171 Vested and expected to vest at December 31 171 188 171 Exercisable at December 31 68 69 30
Share Based Compensation Total Shares Available	Total shares available for the years 2023, 2022 and 2021: 2023 2022 2021 (in thousands) Shares available: Available for grant at January 1 5,062 5,713 6,123 Options granted ( 41 ) ( 42 ) ( 34 ) Options forfeited 2 — 1 Restricted stock units awarded ( 728 ) ( 660 ) ( 447 ) Restricted stock units forfeited 58 51 70 Available for grant at December 31 4,353 5,062 5,713
Weighted-Average Restricted Stock Unit Award Date Fair Value	Weighted average restricted stock unit award date fair value information for the years 2023, 2022 and 2021, is as follows: 2023 2022 2021 Non-vested at January 1 $ 88.71 $ 67.97 $ 47.84 Awarded 105.05 108.74 115.51 Vested 75.55 54.27 43.99 Forfeited 102.12 85.71 65.52 Non-vested at December 31 $ 101.00 $ 88.71 $ 67.97
Restricted Stock Unit Awards Aggregate Intrinsic Value	Restricted stock unit awards aggregate intrinsic value information at December 31 for the years 2023, 2022 and 2021 is as follows: 2023 2022 2021 (in thousands) Vested $ 62,001 $ 95,408 $ 101,679 Outstanding 149,504 115,087 231,763 Expected to vest 135,238 108,666 231,246
Restricted Stock Units Weighted Average Remaining Contractual Terms	Restricted stock units weighted average remaining contractual terms (in years) information at December 31 for the years 2023, 2022 and 2021 is as follows: 2023 2022 2021 Outstanding 1.13 0.99 0.89 Expected to vest 1.13 0.99 0.89
Weighted Average Stock Options Exercise Price	Weighted average stock options exercise price information for the year ended December 31, 2023 is as follows: 2023 Outstanding at January 1 $ 76.52 Options granted 104.15 Options exercised 39.71 Options forfeited 112.57 Options cancelled 113.03 Outstanding at December 31 94.85 Exercisable at December 31 81.53
Stock Option Aggregate Intrinsic Value Information	Stock option aggregate intrinsic value information for the years ended December 31, 2023, 2022 and 2021 is as follows: 2023 2022 2021 (in thousands) Exercised $ 3,901 $ 2,030 $ 6,345 Outstanding 2,647 3,963 17,356 Expected to vest 696 1,583 13,500 Vested and exercisable 1,950 2,380 3,856
Stock Options Weighted Average Remaining Contractual Terms	Stock options weighted average remaining contractual terms (in years) information at December 31, for the years 2023, 2022 and 2021 is as follows: 2023 2022 2021 Outstanding 4.4 4.2 4.4 Expected to vest 5.1 4.8 4.8 Vested and exercisable 3.4 3.1 2.5
Effect to Income (Loss) from Operations for Recording Stock-Based Compensation	The following table provides the effect to income from operations for recording stock-based compensation for the years ended December 31, 2023, 2022, and 2021: 2023 2022 2021 (in thousands) Cost of revenues $ 4,208 $ 4,050 $ 4,196 Engineering and development 10,659 9,992 9,783 Selling and administrative 42,815 34,186 31,664 Stock-based compensation 57,682 48,228 45,643 Income tax benefit ( 10,397 ) ( 11,493 ) ( 14,389 ) Total stock-based compensation expense after income taxes $ 47,285 $ 36,735 $ 31,254

Income Taxes (Tables)

Income Taxes (Tables)	12 Months Ended
	Dec. 31, 2023
Income Tax Disclosure [Abstract]
Schedule of Income (Loss) Before Income Taxes and Provision (Benefit) for Income Taxes from Operations	The components of income before income taxes and the provision (benefit) for income taxes as shown in the consolidated statements of operations were as follows: 2023 2022 2021 (in thousands) Income before income taxes: U.S. $ 307,997 $ 385,968 $ 403,451 Non-U.S. 217,575 454,417 757,504 $ 525,572 $ 840,385 $ 1,160,955 Provision (benefit) for income taxes: Current: U.S. Federal $ 58,063 $ 86,692 $ 58,218 Non-U.S. 54,037 74,204 105,153 State 2,362 2,681 300 114,462 163,577 163,671 Deferred: U.S. Federal ( 27,459 ) ( 36,739 ) ( 15,106 ) Non-U.S. ( 8,584 ) 1,232 ( 4,300 ) State ( 1,599 ) ( 3,186 ) 2,101 ( 37,642 ) ( 38,693 ) ( 17,305 ) Total provision for income taxes: $ 76,820 $ 124,884 $ 146,366
Reconciliation of Effective Tax Rate	A reconciliation of the effective tax rate for the years 2023, 2022 and 2021 is as follows: 2023 2022 2021 U.S. statutory federal tax rate 21.0 % 21.0 % 21.0 % Foreign taxes 2.5 ( 1.9 ) ( 4.5 ) Non-deductible officers’ compensation 1.1 1.3 0.8 U.S. global intangible low-taxed income 0.8 1.2 0.6 State income taxes, net of federal tax benefit 0.1 ( 0.1 ) 0.2 U.S. research and development credit ( 4.2 ) ( 1.8 ) ( 1.4 ) U.S. foreign derived intangible income ( 3.9 ) ( 3.1 ) ( 2.3 ) Foreign tax credits ( 3.3 ) ( 1.0 ) ( 0.5 ) Equity compensation ( 0.4 ) ( 1.1 ) ( 1.0 ) Other, net 0.9 0.4 ( 0.3 ) 14.6 % 14.9 % 12.6 %
Deferred Tax Assets (Liabilities)	Significant components of Teradyne’s deferred tax assets (liabilities) as of December 31, 2023 and 2022 were as follows: 2023 2022 (in thousands) Deferred tax assets: Tax credits $ 112,571 $ 105,503 Research and development 82,571 47,760 Accruals 25,644 30,747 Pension liabilities 24,997 21,335 Lease liabilities 21,167 18,679 Inventory valuations 19,289 22,554 Deferred revenue 13,807 14,909 Equity compensation 7,179 6,578 Vacation accrual 6,096 5,856 Net operating loss carryforwards 5,737 1,857 Investment impairment 3,292 3,292 Intangible assets 2,323 350 Marketable securities 128 2,283 Other 953 2,520 Gross deferred tax assets 325,754 284,223 Less: valuation allowance ( 109,251 ) ( 103,807 ) Total deferred tax assets $ 216,503 $ 180,416 Deferred tax liabilities: Right of use assets $ ( 19,016 ) $ ( 16,607 ) Depreciation ( 16,681 ) ( 19,078 ) Contingent consideration ( 5,214 ) ( 5,214 ) Total deferred tax liabilities $ ( 40,911 ) $ ( 40,899 ) Net deferred assets $ 175,592 $ 139,517
Operating Loss Carryforwards	At December 31, 2023, Teradyne had tax effected operating loss carryforwards that expire in the following years: State Foreign (in thousands) 2024 $ 6 $ — 2025 4 — 2026 — — 2027 — — 2028 23 83 2029-2033 121 500 2034-2038 31 — Beyond 2038 — — Non-expiring 30 4,939 Total $ 215 $ 5,522
Unrecognized Tax Benefits	Teradyne’s gross unrecognized tax benefits for the years ended December 31, 2023, 2022 and 2021 were as follows: 2023 2022 2021 (in thousands) Beginning balance as of January 1 $ 15,608 $ 14,465 $ 17,903 Additions: Tax positions for current year — 1,398 1,417 Tax positions for prior years 3,024 13 30 Reductions: Tax positions for prior years ( 26 ) ( 56 ) ( 1,639 ) Expiration of statutes — ( 212 ) ( 3,246 ) Ending balance as of December 31 $ 18,606 $ 15,608 $ 14,465

Operating Segment, Geographic_2

Operating Segment, Geographic and Significant Customer Information (Tables)	12 Months Ended
	Dec. 31, 2023
Segment Reporting [Abstract]
Segment Information	Segment information for the years ended December 31, 2023, 2022 and 2021 is as follows: Semiconductor System Robotics Wireless Segment Corporate Consolidated (in thousands) 2023 Revenues $ 1,818,636 $ 338,197 $ 375,183 $ 144,282 $ 2,676,298 $ — $ 2,676,298 Income (loss) before taxes (1)(2) 453,320 94,073 ( 54,251 ) 30,568 523,710 1,862 525,572 Total assets (3) 1,329,522 182,084 737,323 68,291 2,317,220 1,169,604 3,486,824 Property additions 113,415 3,643 40,739 1,845 159,642 — 159,642 Depreciation and amortization expense 77,745 3,801 25,527 4,043 111,116 ( 230 ) 110,886 2022 Revenues $ 2,080,590 $ 469,346 $ 403,138 $ 201,720 $ 3,154,794 $ 251 $ 3,155,045 Income (loss) before taxes (1)(2) 634,488 166,879 ( 16,244 ) 66,820 851,943 ( 11,558 ) 840,385 Total assets (3) 1,382,623 165,925 665,638 94,298 2,308,484 1,192,768 3,501,252 Property additions 126,898 7,275 25,712 3,364 163,249 — 163,249 Depreciation and amortization expense 76,532 3,235 25,339 4,991 110,097 578 110,675 2021 Revenues $ 2,642,342 $ 467,739 $ 375,905 $ 216,895 $ 3,702,881 $ — $ 3,702,881 Income (loss) before taxes (1)(2) 976,988 163,064 ( 8,167 ) 83,543 1,215,428 ( 54,473 ) 1,160,955 Total assets (3) 1,245,596 170,954 701,196 107,513 2,225,259 1,584,166 3,809,425 Property additions 115,618 3,905 9,821 3,128 132,472 — 132,472 Depreciation and amortization expense 75,982 3,156 27,336 6,055 112,529 12,956 125,485 (1) Included in Corporate and Eliminations are interest income, interest expense, net foreign exchange gains (losses), intercompany eliminations, pension and postretirement plan actuarial gains (losses), legal and environmental fees, contingent consideration adjustments, acquisition and divestiture related expenses, contract termination settlement charge, an expense for the modification of Teradyne's former chief executive officer's outstanding equity awards, and loss on convertible debt conversions in 2021. (2) Included in income (loss) before taxes are charges and credits related to restructuring and other, inventory charges and loss on convertible debt conversions in 2021. (3) Total assets are attributable to each segment. Semiconductor Test includes $ 34.8 million of total assets classified as assets held for sale. See Note E: “Assets held for sale” for additional information. 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 Years Ended December 31, 2023 2022 2021 (in thousands) Semiconductor Test: Cost of revenues—inventory charge $ 22,482 $ 21,456 $ 6,661 Restructuring and other—employee severance 5,666 — — System Test: Cost of revenues—inventory charge $ 1,855 $ 1,730 $ 641 Restructuring and other—employee severance 1,541 $ — $ — Robotics: Cost of revenues—inventory charge $ 2,275 $ 3,668 $ 6,403 Restructuring and other—employee severance 3,707 2,115 1,210 Restructuring and other—acquisition & divestiture related expenses — — 1,000 Wireless: Cost of revenues—inventory charge $ 1,746 $ 4,598 $ 1,770 Corporate and Eliminations: Selling and administrative—equity modification charge $ 5,889 $ — $ — Restructuring and other—employee severance 3,599 — — Restructuring and other—acquisition & divestiture related expenses 3,562 — ( 513 ) Restructuring and other—contract termination 1,511 — — Restructuring and other—environmental and legal liabilities 1,100 2,700 1,971 Other (income) expense, net—gain on foreign exchange option ( 7,464 ) — — Restructuring and other—legal settlement charge — 14,700 12,000 Restructuring and other—gain on sale of asset — ( 3,410 ) — Other (income) expense, net—loss on convertible debt conversion — — 28,828 Restructuring and other—AutoGuide contingent consideration adjustment — — ( 7,227 )
Revenues by Country	Information as to Teradyne’s revenues by country is as follows: 2023 2022 2021 (in thousands) Revenues from customers (1): United States $ 433,661 $ 469,948 $ 392,626 Korea 394,690 544,816 502,167 Taiwan 384,842 626,424 1,117,874 China 314,899 491,798 631,963 Japan 281,742 162,920 166,231 Europe 273,784 268,384 259,954 Philippines 189,419 124,107 166,838 Singapore 116,969 99,503 121,582 Thailand 91,818 137,356 138,812 Malaysia 89,197 142,203 136,774 Rest of the World 105,277 87,586 68,060 $ 2,676,298 $ 3,155,045 $ 3,702,881 (1) Revenues attributable to a country are based on location of customer site.
Long-Lived Assets by Geographic Area	Long-lived assets by geographic area: United Foreign (1) Total (in thousands) December 31, 2023 (2) $ 322,445 $ 207,995 $ 530,440 December 31, 2022 $ 328,341 $ 164,076 $ 492,417 (1) As of December 31, 2023 and December 31, 2022, long-lived assets attributable to Denmark were $ 78.1 million and $ 42.5 million, respectively. (2) Includes $ 11.5 million of long-lived assets classified as assets held for sale. See Note E: “Assets held for sale” for additional information.

Accounting Policies - Additiona

Accounting Policies - Additional Information (Detail) - USD ($) $ in Thousands		12 Months Ended
	Jan. 01, 2022	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Summary Of Significant Accounting Policies [Line Items]
Retained earnings		$ 706,514	$ 725,729
Standard warranty period		12 months
Depreciation over life to cost of revenues and selling and administrative expenses, years		6 years
Net book value of internally manufactured test systems sold		$ 2,800	6,600	$ 16,600
Advertising costs		15,500	17,300	13,400
Losses (gains) on foreign currency transactions		10,900	10,800	$ (2,100)
Trade Accounts Receivable		243,500	93,900
Retained earnings	$ 1,800
Additional paid-in capital		$ 1,827,274	$ 1,755,963
Teradyne [Member]
Summary Of Significant Accounting Policies [Line Items]
Retained earnings	94,600
Current debt	1,400
Debt	6,600
Mezzanine equity	100,800
Additional paid-in capital	100,800
Teradyne [Member] | Accounting Standards Update 2020-06 [Member] | Revision of Prior Period, Accounting Standards Update, Adjustment [Member]
Summary Of Significant Accounting Policies [Line Items]
Mezzanine equity	$ 0

Deferred Revenue and Customer A

Deferred Revenue and Customer Advances (Detail) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Deferred Revenue Disclosure [Abstract]
Maintenance, service and training	$ 66,458	$ 78,089
Customer advances, undelivered elements and other	35,731	59,147
Extended warranty	34,897	56,180	$ 64,168	$ 51,929
Total deferred revenue and customer advances	$ 137,086	$ 193,416

Warranty Accrual Included in Ot

Warranty Accrual Included in Other Accrued Liabilities (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Product Warranties Disclosures [Abstract]
Balance at beginning of period	$ 14,181	$ 24,577	$ 16,633
Accruals for warranties issued during the period	21,644	21,851	35,727
Accruals related to pre-existing warranties	(1,576)	(5,618)	(6,846)
Settlements made during the period	(18,551)	(26,629)	(20,937)
Balance at end of period	$ 15,698	$ 14,181	$ 24,577

Extended Product Warranty of Sh

Extended Product Warranty of Short and Long-Term Deferred Revenue and Customer Advances (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Product Warranties Disclosures [Abstract]
Balance at beginning of period	$ 56,180	$ 64,168	$ 51,929
Deferral of new extended warranty revenue	14,330	33,686	43,597
Recognition of extended warranty deferred revenue	(35,613)	(41,674)	(31,358)
Balance at end of period	$ 34,897	$ 56,180	$ 64,168

Schedule of Prepayments and Oth

Schedule of Prepayments and Other Current Assets (Detail) - USD ($) $ in Thousands	Dec. 31, 2023	[1]	Dec. 31, 2022
Prepayments [Abstract]
Contract manufacturer and supplier prepayments	$ 502,257		$ 491,105
Prepaid maintenance and other services	17,592		14,545
Prepaid taxes	16,083		18,625
Other prepayments	13,038		8,687
Total prepayments	$ 548,970		$ 532,962
[1] Excludes $ 5.3 million of contract manufacturer and supplier prepayments, classified as assets held for sale. See Note E: “Assets held for sale” for additional information.

Schedule of Prepayments and O_2

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

Useful Lives of Assets (Detail)

Useful Lives of Assets (Detail)	Dec. 31, 2023
Buildings
Property, Plant and Equipment [Line Items]
Useful lives, maximum years	40 years
Building Improvements | Minimum
Property, Plant and Equipment [Line Items]
Useful lives, maximum years	5 years
Building Improvements | Maximum
Property, Plant and Equipment [Line Items]
Useful lives, maximum years	10 years
Leasehold Improvements | Maximum
Property, Plant and Equipment [Line Items]
Useful lives, maximum years	10 years
Furniture and Fixtures
Property, Plant and Equipment [Line Items]
Useful lives, maximum years	10 years
Test Systems Manufactured Internally
Property, Plant and Equipment [Line Items]
Useful lives, maximum years	6 years
Machinery Equipment And Software | Minimum
Property, Plant and Equipment [Line Items]
Useful lives, maximum years	3 years
Machinery Equipment And Software | Maximum
Property, Plant and Equipment [Line Items]
Useful lives, maximum years	5 years

Revenue - Additional Informatio

Revenue - Additional Information (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Disaggregation of Revenue [Line Items]
Deferred Revenue And Customer Advances	$ 108.1	$ 112.4	$ 102.5
Revenue, Remaining Performance Obligation, Amount	$ 1,124.6
Short-term Contract with Customer [Member]
Disaggregation of Revenue [Line Items]
Revenue, Remaining Performance Obligation, Percentage	90%
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction Period	12 months
Long-term Contract with Customer [Member]
Disaggregation of Revenue [Line Items]
Revenue, Remaining Performance Obligation, Percentage	9%
Long-term Contract with Customer [Member] | Maximum [Member]
Disaggregation of Revenue [Line Items]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction Period	3 years
Long-term Contract with Customer [Member] | Minimum [Member]
Disaggregation of Revenue [Line Items]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction Period	1 year
Long Term Contract With Customer Thereafter [Member]
Disaggregation of Revenue [Line Items]
Revenue, Remaining Performance Obligation, Percentage	1%
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction Period

Disaggregated Revenue by Primar

Disaggregated Revenue by Primary Geographical Market, Major Product Line and Timing of Revenue Recognition (Detail) - USD ($) $ in Thousands		12 Months Ended
		Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Disaggregation of Revenue [Line Items]
Total	[1],[2]	$ 2,676,298	$ 3,155,045	$ 3,702,881
System Test
Disaggregation of Revenue [Line Items]
Total	[1]	338,197	469,346	467,739
Wireless Test
Disaggregation of Revenue [Line Items]
Total	[1]	144,282	201,720	216,895
Corporate and Eliminations
Disaggregation of Revenue [Line Items]
Total	[1]		251
Point in Time
Disaggregation of Revenue [Line Items]
Total	[1]	2,259,315	2,772,622	3,335,446
Point in Time | System Test
Disaggregation of Revenue [Line Items]
Total	[1]	268,379	402,074	409,383
Point in Time | Wireless Test
Disaggregation of Revenue [Line Items]
Total	[1]	129,399	189,040	204,247
Point in Time | Corporate and Eliminations
Disaggregation of Revenue [Line Items]
Total	[1]		251
Over Time
Disaggregation of Revenue [Line Items]
Total	[1]	416,983	382,423	367,435
Over Time | System Test
Disaggregation of Revenue [Line Items]
Total	[1]	69,818	67,272	58,356
Over Time | Wireless Test
Disaggregation of Revenue [Line Items]
Total	[1]	14,883	12,680	12,648
Americas
Disaggregation of Revenue [Line Items]
Total	[1]	479,396	475,619	405,736
Americas | System Test
Disaggregation of Revenue [Line Items]
Total	[1]	151,579	146,040	135,230
Americas | Wireless Test
Disaggregation of Revenue [Line Items]
Total	[1]	50,770	47,350	36,173
Americas | Corporate and Eliminations
Disaggregation of Revenue [Line Items]
Total	[1]		251
Europe, Middle East and Africa
Disaggregation of Revenue [Line Items]
Total	[1]	303,891	279,515	265,764
Europe, Middle East and Africa | System Test
Disaggregation of Revenue [Line Items]
Total	[1]	33,231	28,956	25,697
Europe, Middle East and Africa | Wireless Test
Disaggregation of Revenue [Line Items]
Total	[1]	8,097	13,603	8,619
Asia Pacific
Disaggregation of Revenue [Line Items]
Total	[1]	1,893,011	2,399,911	3,031,381
Asia Pacific | System Test
Disaggregation of Revenue [Line Items]
Total	[1]	153,387	294,350	306,812
Asia Pacific | Wireless Test
Disaggregation of Revenue [Line Items]
Total	[1]	85,415	140,767	172,103
SOC | Semiconductor Test
Disaggregation of Revenue [Line Items]
Total	[1]	1,432,621	1,706,884	2,246,730
SOC | Point in Time | Semiconductor Test
Disaggregation of Revenue [Line Items]
Total	[1]	1,141,882	1,445,238	1,989,979
SOC | Over Time | Semiconductor Test
Disaggregation of Revenue [Line Items]
Total	[1]	290,739	261,646	256,751
SOC | Americas | Semiconductor Test
Disaggregation of Revenue [Line Items]
Total	[1]	117,728	122,575	102,702
SOC | Europe, Middle East and Africa | Semiconductor Test
Disaggregation of Revenue [Line Items]
Total	[1]	100,571	69,345	67,381
SOC | Asia Pacific | Semiconductor Test
Disaggregation of Revenue [Line Items]
Total	[1]	1,214,322	1,514,964	2,076,647
Memory | Semiconductor Test
Disaggregation of Revenue [Line Items]
Total	[1]	386,015	373,706	395,612
Memory | Point in Time | Semiconductor Test
Disaggregation of Revenue [Line Items]
Total	[1]	356,417	344,693	365,441
Memory | Over Time | Semiconductor Test
Disaggregation of Revenue [Line Items]
Total	[1]	29,598	29,013	30,171
Memory | Americas | Semiconductor Test
Disaggregation of Revenue [Line Items]
Total	[1]	11,367	11,987	10,665
Memory | Europe, Middle East and Africa | Semiconductor Test
Disaggregation of Revenue [Line Items]
Total	[1]	8,497	1,543	3,503
Memory | Asia Pacific | Semiconductor Test
Disaggregation of Revenue [Line Items]
Total	[1]	366,151	360,176	381,444
Universal Robots (UR) | Robotics
Disaggregation of Revenue [Line Items]
Total	[1]	303,792	325,732	311,182
Universal Robots (UR) | Point in Time | Robotics
Disaggregation of Revenue [Line Items]
Total	[1]	296,252	317,514	305,512
Universal Robots (UR) | Over Time | Robotics
Disaggregation of Revenue [Line Items]
Total	[1]	7,540	8,218	5,670
Universal Robots (UR) | Americas | Robotics
Disaggregation of Revenue [Line Items]
Total	[1]	111,761	112,203	94,897
Universal Robots (UR) | Europe, Middle East and Africa | Robotics
Disaggregation of Revenue [Line Items]
Total	[1]	128,719	139,599	134,829
Universal Robots (UR) | Asia Pacific | Robotics
Disaggregation of Revenue [Line Items]
Total	[1]	63,312	73,930	81,456
MiR | Robotics
Disaggregation of Revenue [Line Items]
Total	[1]	71,391	77,406	64,723
MiR | Point in Time | Robotics
Disaggregation of Revenue [Line Items]
Total	[1]	66,986	73,812	60,884
MiR | Over Time | Robotics
Disaggregation of Revenue [Line Items]
Total	[1]	4,405	3,594	3,839
MiR | Americas | Robotics
Disaggregation of Revenue [Line Items]
Total	[1]	36,191	35,213	26,069
MiR | Europe, Middle East and Africa | Robotics
Disaggregation of Revenue [Line Items]
Total	[1]	24,776	26,469	25,735
MiR | Asia Pacific | Robotics
Disaggregation of Revenue [Line Items]
Total	[1]	$ 10,424	$ 15,724	$ 12,919
[1] Includes $ 5.2 m illion, $ 8.2 million and $ 13.2 million in 2023, 2022 and 2021, respectively, for leases of Teradyne’s systems recognized outside of ASC 606: “Revenue from Contracts with Customers.” Revenues attributable to a country are based on location of customer site.

Disaggregated Revenue by Prim_2

Disaggregated Revenue by Primary Geographical Market, Major Product Line and Timing of Revenue Recognition (Parenthetical) (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Accounting Policies [Abstract]
Revenue on leases	$ 5.2	$ 8.2	$ 13.2

Assets Held for Sale - Addition

Assets Held for Sale - Additional Information (Detail) $ in Millions	Nov. 07, 2023 USD ($)
Device Interface Solutions
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Proceeds from sale of business	$ 85

Schedule of Assets Held-for-sal

Schedule of Assets Held-for-sale (Detail) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Current assets:
Prepayments	$ 5,300
Total current assets held for sale	23,250	$ 0
Total assets held for sale	11,531	0
Current liabilities:
Total current liabilities held for sale	7,379	0
Total liabilities held for sale	2,000	$ 0
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

Composition of Inventories, Net

Composition of Inventories, Net (Detail) - USD ($) $ in Thousands	Dec. 31, 2023	[1]	Dec. 31, 2022
Inventory Disclosure [Abstract]
Raw materials	$ 258,422		$ 256,065
Work-in-process	26,851		37,982
Finished goods	24,701		30,972
Inventories, net	$ 309,974		$ 325,019
[1] Excludes $ 18.0 million of primarily work-in-process inventories, net classified as assets held for sale. See Note E: “Assets held for sale” 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

Property Plant and Equipment, N

Property Plant and Equipment, Net (Detail) - USD ($) $ in Thousands	Dec. 31, 2023	[1]	Dec. 31, 2022
Property, Plant and Equipment [Abstract]
Land	$ 19,487		$ 18,481
Buildings	127,705		128,991
Machinery, equipment and software	1,047,235		1,059,880
Furniture and fixtures	28,093		29,929
Leasehold improvements	66,777		64,631
Construction in progress	54,799		22,470
Property, Plant and Equipment, Gross, Total	1,344,096		1,324,382
Less: accumulated depreciation	898,604		905,699
Property, plant and equipment, net	$ 445,492		$ 418,683
[1] Excludes $ 9.0 million of property, plant and equipment, net classified as assets held for sale. See Note E: “Assets held for sale” for additional information.

Property Plant and Equipment,_2

Property Plant and Equipment, Net (Parenthetical) (Detail) $ in Millions	Dec. 31, 2023 USD ($)
Property, Plant and Equipment [Abstract]
Property, plant and equipment, net classified as assets held for sale	$ 9

Property, Plant and Equipment -

Property, Plant and Equipment - Additional Information (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023		Dec. 31, 2022	Dec. 31, 2021
Property, Plant and Equipment [Line Items]
Depreciation of property, plant and equipment	$ 92,118		$ 90,763	$ 91,073
Machinery and equipment	1,047,235	[1]	1,059,880
Accumulated depreciation	898,604	[1]	905,699
Test Systems Leased By Customers
Property, Plant and Equipment [Line Items]
Machinery and equipment	5,100		5,800
Accumulated depreciation	$ 4,900		$ 5,600
[1] Excludes $ 9.0 million of property, plant and equipment, net classified as assets held for sale. See Note E: “Assets held for sale” for additional information.

Financial Instruments - Additio

Financial Instruments - Additional Information (Detail) $ in Thousands, € in Millions		1 Months Ended	12 Months Ended
	Nov. 07, 2023 EUR (€)	Mar. 31, 2022 USD ($)	Dec. 31, 2023 USD ($)	Dec. 31, 2022 USD ($)	Dec. 31, 2021 USD ($)
Financial Instruments and Fair Value [Line Items]
Available-for-sale securities, realized gain			$ 600	$ 800	$ 3,100
Available-for-sale securities, realized loss			300	1,000	0
Fair market value of investments with unrealized losses greater than one year			65,200	33,400
Fair market value of investments with unrealized losses less than one year			22,300	66,300
Unrealized Gain (loss) on contracts			10,900	10,800	(2,100)
Equity securities unrealized gain			8,900	1,900	5,100
Equity securities unrealized loss			1,700	11,600	1,800
Other comprehensive income (Loss), cash flow hedge, gain (loss), before reclassification, after tax			5,464	(2,517)	$ 0
Technoprobe S.p.A
Financial Instruments and Fair Value [Line Items]
Percentage of investment acquired	10%
Call Option
Financial Instruments and Fair Value [Line Items]
Unrealized Gain (loss) on contracts			7,500
Fair value of outstanding contracts			17,400
Expiration date of the option	Apr. 26, 2024
Call Option | Technoprobe S.p.A
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			$ 600	$ (3,200)
Accounts Receivable | Customer 2 | Minimum
Financial Instruments and Fair Value [Line Items]
Concentration risk, percentage			18%	10%
Debt Mutual Funds
Financial Instruments and Fair Value [Line Items]
Available for sale securities with out contractual maturity date			$ 8,800
Auto Guide Llc [Member] | Dispute In Respect Of Contingent Consideration [Member]
Financial Instruments and Fair Value [Line Items]
Litigation Settlement, Amount settled between parties		$ 26,700
Foreign Exchange Contracts
Financial Instruments and Fair Value [Line Items]
Unrealized Gain (loss) on contracts			$ 1,800	$ 900

Schedule of Fair Value of Finan

Schedule of Fair Value of Financial Assets and Liabilities Measured on Recurring Basis (Detail) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Available for sale securities	$ 132,456	$ 112,871
U.S. Treasury Securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Available for sale securities	41,808	39,649
Commercial Paper
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Available for sale securities	1,667	7,159
Corporate Debt Securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Available for sale securities	52,734	50,856
Certificates of Deposit and Time Deposits
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Available for sale securities	21,772	1,740
U.S. Government Agency Securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Available for sale securities	4,892	6,352
Debt Mutual Funds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Available for sale securities	8,773	6,580
Non-U.S. Government Securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Available for sale securities	810	535
Fair Value, Measurements, Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Total	937,159	1,005,162
Derivative assets	18,746	86
Total	955,905	1,005,248
Derivative liabilities	2,545	4,215
Total	2,545	4,215
Fair Value, Measurements, Recurring | Cash
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Cash and cash equivalents	298,156	632,417
Fair Value, Measurements, Recurring | Cash Equivalents
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Cash and cash equivalents	459,415	222,356
Fair Value, Measurements, Recurring | U.S. Treasury Securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Available for sale securities	41,808	39,649
Fair Value, Measurements, Recurring | Commercial Paper
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Available for sale securities	1,667	7,159
Fair Value, Measurements, Recurring | Corporate Debt Securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Available for sale securities	52,734	50,856
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	21,772	1,740
Fair Value, Measurements, Recurring | U.S. Government Agency Securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Available for sale securities	4,892	6,352
Fair Value, Measurements, Recurring | Debt Mutual Funds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Available for sale securities	8,773	6,580
Fair Value, Measurements, Recurring | Non-U.S. Government Securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Available for sale securities	810	535
Fair Value, Measurements, Recurring | Mutual Funds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Available for sale equity securities	47,132	37,518
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	807,359	838,282
Derivative assets	0	0
Total	807,359	838,282
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	298,156	632,417
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	453,298	161,767
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	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	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	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	0
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	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	8,773	6,580
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	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	47,132	37,518
Significant Other Observable Inputs (Level 2) | Fair Value, Measurements, Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Total	129,800	166,880
Derivative assets	18,746	86
Total	148,546	166,966
Derivative liabilities	2,545	4,215
Total	2,545	4,215
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	6,117	60,589
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	41,808	39,649
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	7,159
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	52,734	50,856
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	21,772	1,740
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	4,892	6,352
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	0
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	810	535
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	0
Significant Unobservable Inputs (Level 3) | Fair Value, Measurements, Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Total	0	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	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	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	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	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	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	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	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	$ 0

Schedule of Reported Financial

Schedule of Reported Financial Assets and Liabilities (Detail) - Fair Value, Measurements, Recurring - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Assets	$ 955,905	$ 1,005,248
Liabilities	2,545	4,215
Other Current Liabilities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Liabilities	2,545	4,215
Cash and Cash Equivalents
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Assets	757,571	854,773
Marketable securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Assets	62,154	39,612
Long-term marketable securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Assets	117,434	110,777
Other Current Assets
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Assets	18,746	86
Quoted Prices in Active Markets for Identical Instruments (Level 1)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Assets	807,359	838,282
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) | Cash and Cash Equivalents
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Assets	751,454	794,184
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	55,905	44,098
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
Significant Other Observable Inputs (Level 2)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Assets	148,546	166,966
Liabilities	2,545	4,215
Significant Other Observable Inputs (Level 2) | Other Current Liabilities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Liabilities	2,545	4,215
Significant Other Observable Inputs (Level 2) | Cash and Cash Equivalents
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Assets	6,117	60,589
Significant Other Observable Inputs (Level 2) | Marketable securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Assets	62,154	39,612
Significant Other Observable Inputs (Level 2) | Long-term marketable securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Assets	61,529	66,679
Significant Other Observable Inputs (Level 2) | Other Current Assets
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Assets	18,746	86
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) | 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
Significant Unobservable Inputs (Level 3) | Other Current Assets
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		Dec. 31, 2023	Dec. 31, 2022
Fair Value, Balance Sheet Grouping, Financial Statement Captions
Marketable securities		$ 132,456	$ 112,871
Carrying Value
Fair Value, Balance Sheet Grouping, Financial Statement Captions
Cash and cash equivalents		757,571	854,773
Marketable securities		179,588	150,389
Derivative assets		18,746	86
Derivative liabilities		2,545	4,215
Convertible debt	[1]	$ 0	$ 50,115
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		$ 757,571	$ 854,773
Marketable securities		179,588	150,389
Derivative assets		18,746	86
Derivative liabilities		2,545	4,215
Convertible debt	[1]	$ 0	$ 139,007
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
[1] The carrying value represents the bifurcated debt component only, while the fair value is based on quoted market prices for the convertible note which includes the equity conversion features.

Schedule of Available for Sale

Schedule of Available for Sale Marketable Securities (Detail) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Schedule of Available-for-sale Securities
Available-for-sale marketable securities, Cost	$ 140,377	$ 123,839
Available-for-sale marketable securities, Unrealized Gain	249	73
Available-for-sale marketable securities, Unrealized (Loss)	(8,170)	(11,041)
Available-for-sale marketable securities, Fair Market Value	132,456	112,871
Available-for-sale marketable securities, Fair Market Value of Investments with Unrealized Losses	87,538	99,763
U.S. Treasury Securities
Schedule of Available-for-sale Securities
Available-for-sale marketable securities, Cost	45,725	44,030
Available-for-sale marketable securities, Unrealized Gain	14	0
Available-for-sale marketable securities, Unrealized (Loss)	(3,931)	(4,381)
Available-for-sale marketable securities, Fair Market Value	41,808	39,649
Available-for-sale marketable securities, Fair Market Value of Investments with Unrealized Losses	35,080	39,649
Commercial Paper
Schedule of Available-for-sale Securities
Available-for-sale marketable securities, Cost	1,633	7,089
Available-for-sale marketable securities, Unrealized Gain	34	70
Available-for-sale marketable securities, Unrealized (Loss)	0	0
Available-for-sale marketable securities, Fair Market Value	1,667	7,159
Available-for-sale marketable securities, Fair Market Value of Investments with Unrealized Losses	0	0
Corporate Debt Securities
Schedule of Available-for-sale Securities
Available-for-sale marketable securities, Cost	56,458	57,006
Available-for-sale marketable securities, Unrealized Gain	201	3
Available-for-sale marketable securities, Unrealized (Loss)	(3,925)	(6,153)
Available-for-sale marketable securities, Fair Market Value	52,734	50,856
Available-for-sale marketable securities, Fair Market Value of Investments with Unrealized Losses	44,263	50,667
Debt Mutual Funds
Schedule of Available-for-sale Securities
Available-for-sale marketable securities, Cost	9,081	6,997
Available-for-sale marketable securities, Unrealized Gain	0	0
Available-for-sale marketable securities, Unrealized (Loss)	(308)	(417)
Available-for-sale marketable securities, Fair Market Value	8,773	6,580
Available-for-sale marketable securities, Fair Market Value of Investments with Unrealized Losses	3,303	3,095
U.S. Government Agency Securities
Schedule of Available-for-sale Securities
Available-for-sale marketable securities, Cost	4,898	6,442
Available-for-sale marketable securities, Unrealized Gain	0	0
Available-for-sale marketable securities, Unrealized (Loss)	(6)	(90)
Available-for-sale marketable securities, Fair Market Value	4,892	6,352
Available-for-sale marketable securities, Fair Market Value of Investments with Unrealized Losses	4,892	6,352
Certificates of Deposit and Time Deposits
Schedule of Available-for-sale Securities
Available-for-sale marketable securities, Cost	21,772	1,740
Available-for-sale marketable securities, Unrealized Gain	0	0
Available-for-sale marketable securities, Unrealized (Loss)	0	0
Available-for-sale marketable securities, Fair Market Value	21,772	1,740
Available-for-sale marketable securities, Fair Market Value of Investments with Unrealized Losses	0	0
Non-U.S. Government Securities
Schedule of Available-for-sale Securities
Available-for-sale marketable securities, Cost	810	535
Available-for-sale marketable securities, Unrealized Gain	0	0
Available-for-sale marketable securities, Unrealized (Loss)	0	0
Available-for-sale marketable securities, Fair Market Value	810	535
Available-for-sale marketable securities, Fair Market Value of Investments with Unrealized Losses	$ 0	$ 0

Schedule Of Foreign Currency Ca

Schedule Of Foreign Currency Cash Flow Hedges (Detail) - Foreign Exchange Forward [Member] - Cash Flow Hedging [Member] - USD ($) $ in Millions	Dec. 31, 2023	Dec. 31, 2022
Derivative, Notional Amount	$ 35.5	$ 101
Short [Member] | U.S. dollar/Japanese yen
Derivative, Notional Amount	0	23.4
Short [Member] | U.S. dollar/Taiwan dollar
Derivative, Notional Amount	0	5.5
Long [Member] | U.S. dollar/Japanese yen
Derivative, Notional Amount	35.5	61.2
Long [Member] | U.S. dollar/Taiwan dollar
Derivative, Notional Amount	$ 0	$ 10.9

Schedule of Reported Available

Schedule of Reported Available for Sale Marketable Securities (Detail) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Schedule of Available-for-sale Securities
Available-for-sale marketable securities, Cost	$ 140,377	$ 123,839
Available-for-sale marketable securities, Unrealized Gain	249	73
Available-for-sale marketable securities, Unrealized (Loss)	(8,170)	(11,041)
Available-for-sale marketable securities, Fair Market Value	132,456	112,871
Available-for-sale marketable securities, Fair Market Value of Investments with Unrealized Losses	87,538	99,763
Marketable securities
Schedule of Available-for-sale Securities
Available-for-sale marketable securities, Cost	62,385	39,950
Available-for-sale marketable securities, Unrealized Gain	36	70
Available-for-sale marketable securities, Unrealized (Loss)	(267)	(408)
Available-for-sale marketable securities, Fair Market Value	62,154	39,612
Available-for-sale marketable securities, Fair Market Value of Investments with Unrealized Losses	34,844	30,713
Long-term marketable securities
Schedule of Available-for-sale Securities
Available-for-sale marketable securities, Cost	77,992	83,889
Available-for-sale marketable securities, Unrealized Gain	213	3
Available-for-sale marketable securities, Unrealized (Loss)	(7,903)	(10,633)
Available-for-sale marketable securities, Fair Market Value	70,302	73,259
Available-for-sale marketable securities, Fair Market Value of Investments with Unrealized Losses	$ 52,694	$ 69,050

Contractual Maturities of Inves

Contractual Maturities of Investments in Debt Securities Held (Detail) $ in Thousands	Dec. 31, 2023 USD ($)
Schedule of Available-for-sale Securities
Due within one year, cost	$ 62,385
Due after 1 year through 5 years, cost	23,703
Due after 5 years through 10 years, cost	6,049
Due after 10 years, cost	39,159
Total, cost	131,296
Due within one year, fair market value	62,154
Due after 1 year through 5 years, fair market value	23,319
Due after 5 years through 10 years, fair market value	5,735
Due after 10 years, fair maket value	32,475
Total, fair market value	$ 123,683

Schedule of Notional Amount of

Schedule of Notional Amount of Derivatives (Detail) - USD ($) $ in Millions	Dec. 31, 2023	Dec. 31, 2022
Intercompany Foreign Currency Balance [Line Items]
Derivative Liability, Notional amounts	$ 152.1
Derivative Asset, Notional amounts		$ 150.7
U.S. dollar/Taiwan dollar
Intercompany Foreign Currency Balance [Line Items]
Derivative Liability, Notional amounts	42.7	29.2
U.S. dollar/Japanese yen
Intercompany Foreign Currency Balance [Line Items]
Derivative Liability, Notional amounts	11	37.1
U.S. dollar/Korean won
Intercompany Foreign Currency Balance [Line Items]
Derivative Liability, Notional amounts	7.2	6.4
U.S. dollar/British pound sterling
Intercompany Foreign Currency Balance [Line Items]
Derivative Liability, Notional amounts	1.5	1.2
Euro/U.S. dollar
Intercompany Foreign Currency Balance [Line Items]
Derivative Asset, Notional amounts	25.3	38.4
Singapore dollar/U.S. dollar
Intercompany Foreign Currency Balance [Line Items]
Derivative Asset, Notional amounts	16.6	33.5
Philippine peso/U.S. dollar
Intercompany Foreign Currency Balance [Line Items]
Derivative Asset, Notional amounts	10.1	2.7
Chinese yuan/U.S. dollar
Intercompany Foreign Currency Balance [Line Items]
Derivative Asset, Notional amounts	1	2.2
Danish krone/U.S. dollar
Intercompany Foreign Currency Balance [Line Items]
Derivative Liability, Notional amounts	36	0
Derivative Asset, Notional amounts	$ 0.7	$ 0

Schedule of Derivative Instrume

Schedule of Derivative Instruments in Statement of Financial Position at Fair Value (Detail) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Derivatives, Fair Value [Line Items]
Derivative assets (liabilities), net	$ 16,200	$ (4,129)
Not Designated as Hedging Instrument | Foreign currency forward contracts | Other Current Assets
Derivatives, Fair Value [Line Items]
Derivative assets	733	86
Not Designated as Hedging Instrument | Foreign currency forward contracts | Other Current Liabilities
Derivatives, Fair Value [Line Items]
Derivative liabilities	(2,545)	(990)
Not Designated as Hedging Instrument | Foreign Exchange Option [Member] | Other Current Assets
Derivatives, Fair Value [Line Items]
Derivative assets	17,364	0
Designated as Hedging Instrument [Member] | Foreign currency forward contracts | Other Current Assets
Derivatives, Fair Value [Line Items]
Derivative assets	648	0
Designated as Hedging Instrument [Member] | Foreign Exchange Option [Member] | Other Current Liabilities
Derivatives, Fair Value [Line Items]
Derivative liabilities	$ 0	$ (3,225)

Schedule of Effect of Derivativ

Schedule of Effect of Derivative Instruments in Statement of Operations Recognized (Detail) - USD ($) $ in Thousands		12 Months Ended
		Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Derivative Instruments, Gain (Loss) [Line Items]
Gain (Loss) on Foreign Currency Derivatives Recorded in Earnings, Net		$ (12,434)	$ (2,733)	$ 6,488
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]	(1,843)	(2,482)	6,488
Other (income) expense, net | Not Designated as Hedging Instrument [Member] | Foreign Exchange Option [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Losses (Gains) on derivatives recognized in statements of operations		(7,464)	0	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		$ (3,127)	$ (251)	$ 0
[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 years ended December 31, 2023, 2022 and 2021 , net losses (gains) from remeasurement of monetary assets and liabilities denominated in foreign currencies were $ 10.9 million, $ 10.8 million, and $( 2.1 ) million, respectively.

Schedule of Effect of Derivat_2

Schedule of Effect of Derivative Instruments in Statement of Operations Recognized (Parenthetical) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Unrealized Gain (loss) on contracts	$ 10.9	$ 10.8	$ (2.1)

Leases - Additional Information

Leases - Additional Information (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Leases, Operating [Abstract]
Total lease expense	$ 42.7	$ 40.1	$ 39.2
Variable lease costs	15.5	14.1	12.6
Short-term leases	$ 1.3	$ 2	$ 1.8
Operating Lease, Weighted Average Remaining Lease Term	6 years 3 months 18 days	5 years 10 months 24 days
Operating Lease, Weighted Average Discount Rate, Percent	5.20%	4.70%

Supplemental Cash Flow Informat

Supplemental Cash Flow Information Related to Leases (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Leases, Operating [Abstract]
Cash paid for amounts included in the measurement of lease liabilities included in operating cash flows:	$ 26,059	$ 20,775	$ 24,593
Right-of-use assets obtained in exchange for new lease obligations	$ 17,987	$ 26,149	$ 34,246

Schedule of Operating Lease, Ma

Schedule of Operating Lease, Maturity (Detail) $ in Thousands	Dec. 31, 2023 USD ($)	[1]
Lessee, Operating Lease, Liability, to be Paid, Fiscal Year Maturity [Abstract]
2024	$ 21,045
2025	18,755
2026	15,074
2027	11,733
2028	7,622
Thereafter	23,906
Total lease payments	98,135
Less imputed interest	(15,521)
Total lease liabilities	$ 82,614
[1] Excludes $ 2.5 million of lease liabilities classified as liabilities held for sale. See Note E: “Assets held for sale” for additional information.

Schedule of Operating Lease, _2

Schedule of Operating Lease, Maturity (Parenthetical) (Detail) $ in Millions	Dec. 31, 2023 USD ($)
Leases, Operating [Abstract]
Lease liabilities classified as liabilities held for sale	$ 2.5

Debt - Additional Information (

Debt - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Thousands, shares in Millions		12 Months Ended
	Dec. 12, 2016	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021	Oct. 05, 2022	Jan. 01, 2022	May 01, 2020
Debt Instrument
Repurchase of common stock		$ 397,241	$ 752,082	$ 600,000
Line of Credit Facility, Maximum Borrowing Capacity					$ 750,000		$ 400,000
Line of Credit Facility, Capacity Available for Specific Purpose Other than for Trade Purchases		$ 200,000
Line of Credit Facility, Interest Rate Description		The interest rate applicable to loans under the Credit Facility are, at Teradyne’s option, equal to either a base rate plus a margin ranging from 0.00% to 0.75% per annum or SOFR plus a margin ranging from 1.10% to 1.85% per annum, based on the consolidated leverage ratio of Teradyne. In addition, Teradyne will pay a commitment fee on the unused portion of the commitments under the Credit Facility ranging from 0.15% to 0.25% per annum, based on the then applicable consolidated leverage ratio.
Term of revolving credit facility							3 years
Available Incremental Amount Under The Credit Facility Not To Exceed Percentage Of Consolidated EBIDTA		15%
Convertible common shares		$ 50,200
Current debt, Conversion		0	50,115
Deferred Tax Assets, Other		953	2,520
Retained Earnings (Accumulated Deficit)		706,514	$ 725,729
Convertible Common Shares [Member]
Debt Instrument
Stock Issued During Period, Value, Stock Options Exercised		$ 1,100
Collateral Pledged [Member]
Debt Instrument
Line of Credit Facility, Interest Rate Description		65
1.25% Convertible Senior Unsecured Notes
Debt Instrument
Aggregate principal amount	$ 460,000	$ 460,000
Debt instrument, interest rate, stated percentage	1.25%
Debt instrument, net proceeds after issuance costs	$ 450,800
Payment for net cost of convertible note hedges net of warrant proceeds	33,000	$ 33,000
Repurchase of common stock	$ 50,100
Repurchase of stock, shares	2
Senior notes maturity date	Dec. 15, 2023
Debt instrument, frequency of periodic payment	payable semiannually in arrears on June 15 and December 15 of each year
Shares that would be issued upon conversion		14.7
Strike price per share of warrant		$ 39.4
Debt instrument, convertible, carrying amount of equity component		$ 100,800
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%
Teradyne [Member]
Debt Instrument
Mezzanine equity						$ 100,800
Current debt, Conversion						1,400
Debt						6,600
Retained Earnings (Accumulated Deficit)						94,600
Teradyne [Member] | Accounting Standards Update 2020-06 [Member]
Debt Instrument
Deferred Tax Assets, Other						1,800
Teradyne [Member] | Accounting Standards Update 2020-06 [Member] | Revision of Prior Period, Accounting Standards Update, Adjustment [Member]
Debt Instrument
Mezzanine equity						$ 0

Components of Convertible Senio

Components of Convertible Senior Notes (Detail) - Convertible Senior Notes [Member] - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Debt Instrument
Debt principal	$ 0	$ 50,228
Unamortized debt issuance fees	0	113
Net carrying amount of convertible debt	$ 0	$ 50,115

Interest Expense on Convertible

Interest Expense on Convertible Senior Notes (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Debt Disclosure [Abstract]
Contractual interest expense on the coupon	$ 312	$ 732
Amortization of the discount component and debt issue fees recognized as interest expense	113	209
Total interest expense on the convertible debt	$ 425	$ 941

Changes in Accumulated Other Co

Changes in Accumulated Other Comprehensive Income (loss) (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance	$ 2,451,294	$ 2,562,444	$ 2,207,018
Other comprehensive income (loss)	22,890	(43,920)	(39,464)
Balance	2,525,897	2,451,294	2,562,444
Foreign Currency Translation Reclassification Adjustments
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance	(39,849)	(10,818)
Other comprehensive (loss) gain before reclassifications, net of tax	17,407	(29,031)
Amounts reclassified from accumulated other comprehensive income (loss), net of tax	0	0
Other comprehensive income (loss)	17,407	(29,031)
Balance	(22,442)	(39,849)	(10,818)
Unrealized Gains (Losses) on Marketable Securities
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance	(8,661)	3,704
Other comprehensive (loss) gain before reclassifications, net of tax	2,423	(12,666)
Amounts reclassified from accumulated other comprehensive income (loss), net of tax	44	301
Other comprehensive income (loss)	2,467	(12,365)
Balance	(6,194)	(8,661)	3,704
Unrealized (Losses) Gains on Cash Flow Hedges
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance	(2,517)	0
Other comprehensive (loss) gain before reclassifications, net of tax	5,464	(2,517)
Amounts reclassified from accumulated other comprehensive income (loss), net of tax	(2,441)	0
Other comprehensive income (loss)	3,023	(2,517)
Balance	506	(2,517)	0
Amortization of Prior Service Credit
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance	1,159	1,166
Other comprehensive (loss) gain before reclassifications, net of tax	0	0
Amounts reclassified from accumulated other comprehensive income (loss), net of tax	(7)	(7)	(7)
Other comprehensive income (loss)	(7)	(7)
Balance	1,152	1,159	1,166
Accumulated Other Comprehensive Income (Loss)
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance	(49,868)	(5,948)	33,516
Other comprehensive (loss) gain before reclassifications, net of tax	25,294	(44,214)
Amounts reclassified from accumulated other comprehensive income (loss), net of tax	(2,404)	294	(1,002)
Other comprehensive income (loss)	22,890	(43,920)	(39,464)
Balance	$ (26,978)	$ (49,868)	$ (5,948)

Changes in Accumulated Other _2

Changes in Accumulated Other Comprehensive Income (Loss) (Parenthetical) (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Accumulated Other Comprehensive Income (Loss) [Line Items]
Amounts reclassified from accumulated other comprehensive income (loss), tax	$ (676)	$ 23	$ (279)
Foreign currency translation adjustments, tax	0	0	0
Unrealized (losses) gains on marketable securities, tax	(1,728)	(2,308)	1,055
Unrealized Losses on Cash Flow Hedges	143	(708)	0
Retirement plans prior service benefit, tax	(1,132)	(1,130)	(1,128)
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	568	(3,388)
Amounts reclassified from accumulated other comprehensive income (loss), tax	12	25	(277)
Other comprehensive income (loss), tax	580	(3,363)
Unrealized (Losses) Gains on Cash Flow Hedges
Accumulated Other Comprehensive Income (Loss) [Line Items]
Other comprehensive income (loss) before reclassifications, tax	1,537	(708)
Amounts reclassified from accumulated other comprehensive income (loss), tax	(686)	0
Other comprehensive income (loss), tax	851	(708)
Amortization of 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	(2)	(2)	$ (2)
Other comprehensive income (loss), tax	$ (2)	$ (2)

Reclassifications Out of Accumu

Reclassifications Out of Accumulated Other Comprehensive Income (Loss) to Statements of Operations (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Interest income (expense)	$ (44)	$ (301)	$ 995
Unrealized gains, net of tax	2,441	0	0
AOCI, Accumulated Gain (Loss), Debt Securities, Available-for-Sale, Parent [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Interest income (expense)	(44)	(301)	995
Reclassifications, net of tax	(44)	(301)
Amortization of Prior Service Credit
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Reclassifications, net of tax	7	7	7
Accumulated Other Comprehensive Income (Loss)
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Reclassifications, net of tax	$ 2,404	$ (294)	$ 1,002

Reclassifications Out of Accu_2

Reclassifications Out of Accumulated Other Comprehensive Income (Loss) to Statements of Operations (Parenthetical) (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Reclassifications, tax	$ 676	$ (23)	$ 279
Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), Reclassification, Tax	686	0	0
Unrealized (Losses) Gains on Marketable Securities
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Reclassifications, tax	(12)	(25)	277
Amortization of Prior Service Credit
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Reclassifications, tax	$ 2	$ 2	$ 2

Goodwill and Intangible Asset_2

Goodwill and Intangible Assets - Additional Information (Detail) - USD ($) $ in Thousands	3 Months Ended		12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Goodwill and Intangible Assets Disclosure [Abstract]
Goodwill, Impairment Loss	$ 0	$ 0
Acquired intangible assets amortization			$ 18,999	$ 19,333	$ 21,456

Changes in Carrying Amount of G

Changes in Carrying Amount of Goodwill by Segment (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2023
Goodwill [Line Items]
Goodwill	$ 1,165,761	$ 1,188,590	$ 1,178,218
Accumulated impairment losses	(762,566)	(762,566)	(762,566)
Foreign currency translation adjustment	12,457	(22,829)
Total Goodwill	403,195	426,024	415,652
Robotics
Goodwill [Line Items]
Goodwill	383,166	405,971	395,463
Foreign currency translation adjustment	12,297	(22,805)
Total Goodwill	383,166	405,971	395,463
Wireless Test
Goodwill [Line Items]
Goodwill	361,819	361,819	361,819
Accumulated impairment losses	(353,843)	(353,843)	(353,843)
Total Goodwill	7,976	7,976	7,976
Semiconductor Test
Goodwill [Line Items]
Goodwill	262,077	262,101	262,237
Accumulated impairment losses	(260,540)	(260,540)	(260,540)
Foreign currency translation adjustment	160	(24)
Total Goodwill	1,537	1,561	1,697
System Test
Goodwill [Line Items]
Goodwill	158,699	158,699	158,699
Accumulated impairment losses	(148,183)	(148,183)	(148,183)
Total Goodwill	$ 10,516	$ 10,516	$ 10,516

Schedule of Amortizable Intangi

Schedule of Amortizable Intangible Assets (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Finite-Lived Intangible Assets
Gross Carrying Amount	$ 378,822	$ 388,093
Accumulated Amortization	(337,062)	(327,324)
Foreign Currency Translation Adjustment	(6,356)	(7,291)
Net Carrying Amount	35,404	53,478
Developed technology
Finite-Lived Intangible Assets
Gross Carrying Amount	267,706	270,967
Accumulated Amortization	(243,191)	(234,208)
Foreign Currency Translation Adjustment	(5,343)	(5,935)
Net Carrying Amount	19,172	30,824
Customer Relationships
Finite-Lived Intangible Assets
Gross Carrying Amount	52,109	57,739
Accumulated Amortization	(47,850)	(51,186)
Foreign Currency Translation Adjustment	232	172
Net Carrying Amount	4,491	6,725
Trademarks and tradenames
Finite-Lived Intangible Assets
Gross Carrying Amount	59,007	59,387
Accumulated Amortization	(46,021)	(41,930)
Foreign Currency Translation Adjustment	(1,245)	(1,528)
Net Carrying Amount	$ 11,741	$ 15,929

Schedule of Amortizable Intan_2

Schedule of Amortizable Intangible Assets (Parenthetical) (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Goodwill and Intangible Assets Disclosure [Abstract]
Impairment of intangible assets	$ 9.3	$ 1.6
Impairment, Intangible Asset, Finite-Lived, Statement of Income or Comprehensive Income [Extensible Enumeration]	Intangible Assets, Net (Excluding Goodwill)	Intangible Assets, Net (Excluding Goodwill)

Schedule of Estimated Intangibl

Schedule of Estimated Intangible Asset Amortization Expense (Detail) $ in Thousands	Dec. 31, 2023 USD ($)
Goodwill and Intangible Assets Disclosure [Abstract]
2024	$ 18,983
2025	11,402
2026	2,390
2027	1,173
2028	1,092
Thereafter	$ 364

Commitments and Contingencies -

Commitments and Contingencies - Additional Information (Detail) - USD ($) $ in Millions		1 Months Ended	12 Months Ended
	Mar. 08, 2021	Mar. 31, 2022	Dec. 31, 2023	Dec. 31, 2022
Purchase Commitment, Excluding Long-term Commitment
Aggregate purchase commitments			$ 414.4
Purchase commitments less than one year			379.1
Product warranty accrual			15.7	$ 14.2
Revenue deferrals related to extended warranties			$ 34.9	$ 56.2
Auto Guide Llc [Member] | Dispute In Respect Of Contingent Consideration [Member]
Purchase Commitment, Excluding Long-term Commitment
Legal claims, damage sought by party	$ 106.9
Litigation Settlement, Amount settled between parties		$ 26.7

Computation of Basic and Dilute

Computation of Basic and Diluted Net Income Per Common Share (Detail) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands		12 Months Ended
		Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Net Income Loss Per Common Share
Net income		$ 448,752	$ 715,501	$ 1,014,589
Weighted average common shares-basic		154,310	158,434	164,960
Convertible note hedge warrant shares	[1]	8,897	8,806	9,956
Incremental shares from assumed conversion of convertible notes	[2]	633	1,763	7,435
Employee stock purchase rights		7	22	8
Dilutive potential common shares		9,994	11,300	18,665
Weighted average common shares-diluted		164,304	169,734	183,625
Net income per common share-basic		$ 2.91	$ 4.52	$ 6.15
Net income per common share-diluted		$ 2.73	$ 4.22	$ 5.53
Restricted Stock Units
Net Income Loss Per Common Share
Incremental shares attributable to share based payment arrangements		423	657	1,180
Employee Stock Option
Net Income Loss Per Common Share
Incremental shares attributable to share based payment arrangements		34	52	86
[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 the assumed conversion of the convertible notes was 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 debt, was divided by the average Teradyne stock price for the period.

Net Income Per Common Share - A

Net Income Per Common Share - Additional Information (Detail) - shares shares in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Employee Stock Option [Member]
Net Income Loss Per Common Share
Exercise of stock options	0.1	0.1
Restricted Stock Units (RSUs) [Member]
Net Income Loss Per Common Share
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount	0.1	0.4

Restructuring and Other - Addit

Restructuring and Other - Additional Information (Detail) - USD ($) $ in Thousands		12 Months Ended
	Mar. 25, 2022	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Restructuring Cost and Reserve
Increase Decrease in environmental and legal liabilities			$ 2,700
Severance benefit and charges		$ 14,700	2,900
Contingent consideration adjustment		0	0	$ (7,227)
Contract termination charge		1,500
Increase in environmental liability others		1,100
Gains on sale of asset		0	3,410	0
Settled Litigation [Member]
Restructuring Cost and Reserve
Legal settlement charges			14,700
Litigation Settlement, Amount settled between parties				12,000
Gains on sale of asset			$ 3,400
Semiconductor Test
Restructuring Cost and Reserve
Restructuring and other- other				2,500
Acquisition related costs				500
Mobile Industrial Robots (MiR)
Restructuring Cost and Reserve
Contingent consideration adjustment				7,200
Technoprobe
Restructuring Cost and Reserve
Acquisition and divestiture expenses		$ 3,100
TER Corporate And Eliminations | Universal Robots (UR)
Restructuring Cost and Reserve
Contingent consideration adjustment				$ 1,500
TER Corporate And Eliminations | TER Dispute In Respect Of Contingent Consideration [Member]
Restructuring Cost and Reserve
Litigation Settlement, Amount settled between parties	$ 26,700

Retirement Plans - Additional I

Retirement Plans - Additional Information (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Defined Benefit Plan Disclosure
Fair value of pension plans assets totaled	$ 114,500
UNITED STATES
Defined Benefit Plan Disclosure
Acturial gains (losses) on benefit obligations	(3,229)	$ 45,932
Accumulated benefit obligation for defined benefit pension plans	$ 142,200	$ 140,600
Percentage of expected return on plan assets assumption	4.80%	2%	2.40%
Discount rate utilized to determine future pension obligations	4.70%	4.90%
Fair value of pension plans assets totaled	$ 112,617	$ 111,760	$ 149,578
Contribution to defined benefit pension plans	3,051	3,217
Foreign Pension Plans, Defined Benefit
Defined Benefit Plan Disclosure
Acturial gains (losses) on benefit obligations	(2,738)	13,181
Accumulated benefit obligation for defined benefit pension plans	$ 32,600	$ 28,600
Percentage of expected return on plan assets assumption	1.80%	4%	3.50%
Discount rate utilized to determine future pension obligations	3%	3.50%
Fair value of pension plans assets totaled	$ 1,929	$ 2,087	$ 2,017
Contribution to defined benefit pension plans	$ 1,028	$ 949
United States Plans
Defined Benefit Plan Disclosure
Percentage of expected return on plan assets assumption	4.75%
Discount rate utilized to determine future pension obligations	4.70%	4.90%
Fair value of pension plans assets totaled	$ 112,600
U.S. Supplemental Executive Defined Benefit Pension Plan
Defined Benefit Plan Disclosure
Contribution to defined benefit pension plans	3,100	$ 3,200
Contribution to defined benefit pension plans in 2018	7,100	3,100
Contribution to defined benefit pension plans in One to Three Years	6,600
Contribution to defined benefit pension plans thereafter	16,900
Non-United States Subsidiaries
Defined Benefit Plan Disclosure
Contribution to defined benefit pension plans	1,000	900
Contribution to defined benefit pension plans in 2018	2,500	1,400
Contribution to defined benefit pension plans in One to Three Years	2,300
Contribution to defined benefit pension plans thereafter	7,900
Taiwan Defined Benefit Pension Plan
Defined Benefit Plan Disclosure
Fair value of pension plans assets totaled	1,900
German Plan [Member]
Defined Benefit Plan Disclosure
Defined Benefit Plan, decrease in benefit obligation	1,000	3,100
Acturial gains (losses) on benefit obligations	6,000	$ 59,100
U.S. Postretirement Benefit Plan [Member]
Defined Benefit Plan Disclosure
Contribution to defined benefit pension plans in 2018	1,200
Contribution to defined benefit pension plans in One to Three Years	1,600
Contribution to defined benefit pension plans thereafter	2,000
Contribution to defined benefit pension plans	$ 1,500

Schedule of Defined Benefit Pen

Schedule of Defined Benefit Pension and Postretirement Benefit Plan Assets and Obligation (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Defined Benefit Plan Disclosure
Ending Balance	$ 114,500
UNITED STATES
Defined Benefit Plan Disclosure
Projected benefit obligation, Beginning of year	143,814	$ 192,472
Service cost	1,063	1,588	$ 1,784
Interest cost	6,888	4,886	4,427
Actuarial loss (gain)	3,229	(45,932)
Benefits paid	(10,807)	(9,200)
Liability (gain) loss due to settlement	0	0
Non-U.S. currency movement	0	0
Projected benefit obligation, End of year	144,187	143,814	192,472
Beginning Balance	111,760	149,578
Actual return on plan assets	8,613	(31,835)
Company contributions	3,051	3,217
Benefits paid	(10,807)	(9,200)
Settlements gain	0	0
Non-U.S. currency movement	0	0
Ending Balance	112,617	111,760	149,578
Funded status	(31,570)	(32,054)
Foreign Pension Plans, Defined Benefit
Defined Benefit Plan Disclosure
Projected benefit obligation, Beginning of year	29,935	45,774
Service cost	446	784	941
Interest cost	1,057	482	337
Actuarial loss (gain)	2,738	(13,181)
Benefits paid	(947)	(863)
Liability (gain) loss due to settlement	(254)	0
Non-U.S. currency movement	1,009	(3,061)
Projected benefit obligation, End of year	33,984	29,935	45,774
Beginning Balance	2,087	2,017
Actual return on plan assets	43	153
Company contributions	1,028	949
Benefits paid	(947)	(863)
Settlements gain	(254)	0
Non-U.S. currency movement	(28)	(169)
Ending Balance	1,929	2,087	2,017
Funded status	(32,055)	(27,848)
Postretirement Benefit Plans
Defined Benefit Plan Disclosure
Projected benefit obligation, Beginning of year	5,345	7,210
Service cost	34	64	64
Interest cost	299	177	170
Actuarial loss (gain)	155	(1,155)
Benefits paid	(1,413)	(950)
Special termination benefits	2,513	0
Projected benefit obligation, End of year	6,933	5,345	7,210
Beginning Balance	0	0
Company contributions	1,413	950
Benefits paid	(1,413)	(950)
Ending Balance	0	0	$ 0
Funded status	$ (6,933)	$ (5,345)

Schedule of Amounts Recorded wi

Schedule of Amounts Recorded within Statements of Financial Position (Detail) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Defined Benefit Plan Disclosure [Line Items]
Retirement plans assets	$ 11,504	$ 11,761
UNITED STATES
Defined Benefit Plan Disclosure [Line Items]
Retirement plans assets	11,504	11,761
Accrued employees' compensation and withholdings	(3,110)	(3,055)
Retirement plans liabilities	(39,964)	(40,760)
Funded status	(31,570)	(32,054)
Foreign Pension Plans, Defined Benefit
Defined Benefit Plan Disclosure [Line Items]
Accrued employees' compensation and withholdings	(1,255)	(1,191)
Retirement plans liabilities	(30,800)	(26,657)
Funded status	(32,055)	(27,848)
Postretirement Benefit Plans
Defined Benefit Plan Disclosure [Line Items]
Accrued employees' compensation and withholdings	(1,508)	(853)
Retirement plans liabilities	(5,425)	(4,492)
Funded status	$ (6,933)	$ (5,345)

Schedule of Amounts Recognized

Schedule of Amounts Recognized in Accumulated Other Comprehensive Income (loss) (Detail) - Postretirement Benefit Plans - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Defined Benefit Plan Disclosure
Prior service cost, before tax	$ (23)	$ (31)
Deferred taxes	(1,691)	(1,689)
Total recognized in other comprehensive income (loss), net of tax	$ (1,714)	$ (1,720)

Schedule of Pension Plans with

Schedule of Pension Plans with Accumulated Benefit Obligation and Projected Benefit Obligation in Excess of Plan Assets (Detail) - USD ($) $ in Millions	Dec. 31, 2023	Dec. 31, 2022
UNITED STATES
Defined Benefit Plan Disclosure
Projected benefit obligation	$ 43.1	$ 43.8
Accumulated benefit obligation	42.6	42.3
Foreign Pension Plans, Defined Benefit
Defined Benefit Plan Disclosure
Projected benefit obligation	34	29.9
Accumulated benefit obligation	32.5	28.6
Fair value of plan assets	$ 1.9	$ 2.1

Schedule of Net Periodic Pensio

Schedule of Net Periodic Pension and Postretirement Cost (Income) (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Defined Benefit Plan Disclosure
Net actuarial loss (gain)	$ 2,703	$ (25,584)	$ (2,217)
Defined Benefit Plan, Net Periodic Benefit Cost (Credit) Excluding Service Cost, Statement of Income or Comprehensive Income [Extensible Enumeration]	Amortization of Intangible Assets
UNITED STATES
Defined Benefit Plan Disclosure
Service cost	$ 1,063	1,588	1,784
Interest cost	6,888	4,886	4,427
Expected return on plan assets	(5,194)	(2,927)	(3,858)
Net actuarial loss (gain)	18	(11,170)	643
Settlement (gain) loss	(209)		(204)
Total net periodic pension cost (income)	2,566	(7,623)	2,792
Foreign Pension Plans, Defined Benefit
Defined Benefit Plan Disclosure
Service cost	446	784	941
Interest cost	1,057	482	337
Expected return on plan assets	(45)	(75)	(67)
Net actuarial loss (gain)	2,735	(13,259)	(2,223)
Settlement (gain) loss	5
Total net periodic pension cost (income)	4,198	(12,068)	(1,012)
Postretirement Benefit Plans
Defined Benefit Plan Disclosure
Service cost	34	64	64
Interest cost	299	177	170
Amortization of prior service cost	(9)	(9)	(9)
Net actuarial loss (gain)	155	(1,155)	(433)
Special termination benefits	2,513	0
Total net periodic pension cost (income)	2,992	(923)	(208)
Prior service cost	9	9	9
Total recognized in other comprehensive income	9	9	9
Total recognized in net periodic pension cost (income) and other comprehensive income	$ 3,001	$ (914)	$ (199)

Schedule of Weighted Average -

Schedule of Weighted Average - Assumptions to Determine Net Periodic Pension Cost (Detail)	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
UNITED STATES
Defined Benefit Plan Disclosure
Discount rate	3.50%	2.50%	2.20%
Expected return on plan assets	4.80%	2%	2.40%
Salary progression rate	2.40%	2.40%	2.40%
Foreign Pension Plans, Defined Benefit
Defined Benefit Plan Disclosure
Discount rate	3.50%	1.10%	0.70%
Expected return on plan assets	1.80%	4%	3.50%
Salary progression rate	2.10%	2.20%	2.30%
Postretirement Benefit Plans
Defined Benefit Plan Disclosure
Discount rate	5%	2.60%	2.20%
Initial health care cost trend rate	7.20%	7.30%	7.30%
Ultimate health care cost trend rate	4.50%	4.50%	4.50%
Year in which ultimate health care cost trend rate is reached	2032	2029	2029

Schedule of Weighted Average As

Schedule of Weighted Average Assumptions to Determine Pension Obligations (Detail)	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Postretirement Benefit Plans
Defined Benefit Plan Disclosure
Discount rate	4.70%	5%	2.60%
Initial health care trend	7.70%	7.20%	7.30%
Ultimate health care trend	4.50%	4.50%	4.50%
Medical cost trend rate decrease to ultimate rate in year	2033	2032	2029
UNITED STATES
Defined Benefit Plan Disclosure
Discount rate	4.70%	4.90%
Salary progression rate	2.50%	2.50%
Foreign Pension Plans, Defined Benefit
Defined Benefit Plan Disclosure
Discount rate	3%	3.50%
Salary progression rate	2.40%	2.10%

Schedule of Weighted Average Pe

Schedule of Weighted Average Pension Assets Allocations by Category (Detail)	Dec. 31, 2023	Dec. 31, 2022
UNITED STATES
Defined Benefit Plan Disclosure
Total	100%	100%
UNITED STATES | Fixed income securities
Defined Benefit Plan Disclosure
Total	94%	94%
UNITED STATES | Equity securities
Defined Benefit Plan Disclosure
Total	5%	5%
UNITED STATES | Other than Securities Investment
Defined Benefit Plan Disclosure
Total	1%	1%
Foreign Pension Plans, Defined Benefit
Defined Benefit Plan Disclosure
Total	100%	100%
Foreign Pension Plans, Defined Benefit | Other than Securities Investment
Defined Benefit Plan Disclosure
Total	100%	100%

Schedule of Target Assets Alloc

Schedule of Target Assets Allocation (Detail)	Dec. 31, 2023
Bloomberg U.S. Corporate A or Better Index, 20+ Year Index | U.S. corporate fixed income
Defined Benefit Plan Disclosure
Target assets allocation percentage	43%
Bloomberg U.S. Corporate A or Better Index, 5- 20 Year Index | U.S. corporate fixed income
Defined Benefit Plan Disclosure
Target assets allocation percentage	32%
Bloomberg U.S. 3 - 10 Year Treasury Bond Index | U.S. government fixed income
Defined Benefit Plan Disclosure
Target assets allocation percentage	14%
MSCI World Index | Global equity
Defined Benefit Plan Disclosure
Target assets allocation percentage	5%
ICE BofA BB-B U.S. High Yield Constrained Index | High yield fixed income
Defined Benefit Plan Disclosure
Target assets allocation percentage	5%
ICE BofA 3-Month Treasury Bill Index | Cash
Defined Benefit Plan Disclosure
Target assets allocation percentage	1%

Schedule of Target Assets All_2

Schedule of Target Assets Allocation (Parenthetical) (Detail)	12 Months Ended
	Dec. 31, 2023
Bloomberg U.S. Corporate A or Better Index, 20+ Year Index | U.S. corporate fixed income
Defined Benefit Plan Disclosure [Line Items]
Policy index period description	20+ Year
Bloomberg U.S. Corporate A or Better Index, 5- 20 Year Index | U.S. corporate fixed income | Minimum
Defined Benefit Plan Disclosure [Line Items]
Policy index duration period	5 years
Bloomberg U.S. Corporate A or Better Index, 5- 20 Year Index | U.S. corporate fixed income | Maximum
Defined Benefit Plan Disclosure [Line Items]
Policy index duration period	20 years
Bloomberg U.S. 3 - 10 Year Treasury Bond Index | U.S. government fixed income | Minimum
Defined Benefit Plan Disclosure [Line Items]
Policy index duration period	3 years
Bloomberg U.S. 3 - 10 Year Treasury Bond Index | U.S. government fixed income | Maximum
Defined Benefit Plan Disclosure [Line Items]
Policy index duration period	10 years
ICE BofA 3-Month Treasury Bill Index | Cash
Defined Benefit Plan Disclosure [Line Items]
Policy index duration period	3 months

Schedule of Fair Value of Pensi

Schedule of Fair Value of Pensions Plan Assets by Asset Category (Detail) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Defined Benefit Plan Disclosure
Total	$ 114,500
UNITED STATES
Defined Benefit Plan Disclosure
Total	112,617	$ 111,760	$ 149,578
UNITED STATES | Quoted Prices in Active Markets for Identical Instruments (Level 1)
Defined Benefit Plan Disclosure
Total	1,138	1,147
UNITED STATES | Significant Other Observable Inputs (Level 2)
Defined Benefit Plan Disclosure
Total	111,479	110,613
UNITED STATES | Corporate Debt Securities
Defined Benefit Plan Disclosure
Total	89,971	89,403
UNITED STATES | Corporate Debt Securities | Significant Other Observable Inputs (Level 2)
Defined Benefit Plan Disclosure
Total	89,971	89,403
UNITED STATES | US Government Debt Securities
Defined Benefit Plan Disclosure
Total	15,817	15,631
UNITED STATES | US Government Debt Securities | Significant Other Observable Inputs (Level 2)
Defined Benefit Plan Disclosure
Total	15,817	15,631
UNITED STATES | Global equity Securities
Defined Benefit Plan Disclosure
Total	5,691	5,579
UNITED STATES | Global equity Securities | Significant Other Observable Inputs (Level 2)
Defined Benefit Plan Disclosure
Total	5,691	5,579
UNITED STATES | Cash and Cash Equivalents
Defined Benefit Plan Disclosure
Total	1,138	1,147
UNITED STATES | Cash and Cash Equivalents | Quoted Prices in Active Markets for Identical Instruments (Level 1)
Defined Benefit Plan Disclosure
Total	1,138	1,147
Foreign Pension Plans, Defined Benefit
Defined Benefit Plan Disclosure
Total	1,929	2,087	$ 2,017
Foreign Pension Plans, Defined Benefit | Significant Other Observable Inputs (Level 2)
Defined Benefit Plan Disclosure
Total	1,929	2,087
Foreign Pension Plans, Defined Benefit | Other
Defined Benefit Plan Disclosure
Total	1,929	2,087
Foreign Pension Plans, Defined Benefit | Other | Significant Other Observable Inputs (Level 2)
Defined Benefit Plan Disclosure
Total	$ 1,929	$ 2,087

Schedule of Expected Future Ben

Schedule of Expected Future Benefit Payments (Detail) $ in Thousands	Dec. 31, 2023 USD ($)
UNITED STATES
Defined Benefit Plan Disclosure
2024	$ 10,210
2025	9,720
2026	9,863
2027	10,792
2028	10,795
2029-2032	51,857
Foreign Pension Plans, Defined Benefit
Defined Benefit Plan Disclosure
2024	1,312
2025	1,068
2026	1,191
2027	1,301
2028	1,238
2029-2032	8,832
Postretirement Benefit Plans
Defined Benefit Plan Disclosure
2024	1,508
2025	568
2026	701
2027	637
2028	924
2029-2032	$ 2,004

Stock-Based Compensation - Addi

Stock-Based Compensation - Additional Information (Detail) - USD ($)	1 Months Ended						12 Months Ended
	Jul. 31, 2023	Jan. 31, 2023	Jul. 31, 2022	Jan. 31, 2022	Jul. 31, 2021	Jan. 31, 2021	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Share-based Compensation Arrangement by Share-based Payment Award
Allocated share-based compensation expense.							$ 57,682,000	$ 48,228,000	$ 45,643,000
Total shareholder return performance measurement period							3 years
Restricted stock unit awards granted							728,000	660,000	447,000
Weighted average grant date fair value of restricted stock units granted							$ 105.05	$ 108.74	$ 115.51
Stock price							$ 104.15	$ 112.12	$ 113.48
Tax benefit from compensation expense							$ 10,397,000	$ 11,493,000	$ 14,389,000
Total unrecognized expense related to non-vested restricted stock unit awards and stock options							$ 73,700,000
Unrecognized expense related to non-vested restricted stock unit awards and stock options expected to be recognized over weighted average period, in years							2 years 6 months
Maximum percent of shares allowed to purchase							10%
Fair market value							$ 25,000
Maximum number of shares allowed to purchase							6,000
Percentage of common stock price paid							85%
Common stock issued to employees	200,000	200,000	200,000	200,000	100,000	100,000
Value of common stock issued to employees per share	$ 94.64		$ 76.12		$ 113.87		$ 92.25	$ 74.25	$ 139
Number of shares available for grant							4,353,000	5,062,000	5,713,000	6,123,000
Retirement Agreement [Member]
Share-based Compensation Arrangement by Share-based Payment Award
Allocated share-based compensation expense.							$ 5,900,000
Employee Stock Option [Member]
Share-based Compensation Arrangement by Share-based Payment Award
Cash received from employees, employee stock options exercises							2,200,000	$ 900,000	$ 3,100,000
Tax benefit from compensation expense							$ 200,000	$ 100,000	$ 400,000
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							$ 0.44		$ 0.4
Restricted Stock Units
Share-based Compensation Arrangement by Share-based Payment Award
Restricted stock unit awards granted							728,000	660,000	447,000
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							100,000	100,000	100,000
Weighted average grant date fair value of restricted stock units granted							$ 139.04	$ 101.06	$ 125.02
Stock price							104.12	112.12	113.48
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							$ 0.44	$ 0.44	$ 0.4
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
Share-based Compensation Arrangement by Share-based Payment Award
Number of shares available for grant							3,500,000
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							100,000	100,000	100,000
Weighted average grant date fair value of restricted stock units granted							$ 102.91	$ 110.84	$ 113.65
Service-Based Restricted Stock Units | Employees
Share-based Compensation Arrangement by Share-based Payment Award
Restricted stock unit awards granted							500,000	400,000	300,000
Weighted average grant date fair value of restricted stock units granted							$ 102.45	$ 109.42	$ 114.16
Service-Based Restricted Stock Units | Non Employees
Share-based Compensation Arrangement by Share-based Payment Award
Weighted average grant date fair value of restricted stock units granted							$ 90.5	$ 105.93	$ 128.7
Service-Based Restricted Stock Units | Executive Officer
Share-based Compensation Arrangement by Share-based Payment Award
Restricted stock unit awards granted							100,000	100,000	100,000
TERService Based Stock Options | Non Employee Directors
Share-based Compensation Arrangement by Share-based Payment Award
Restricted stock unit awards granted							100,000	100,000	100,000
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							$ 41.23	$ 39.01	$ 36.6

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	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Share-based Compensation Arrangement by Share-based Payment Award
Risk-free interest rate	4%	1.40%	0.20%
Expected historical volatility	49.70%	47.10%	43.90%
Dividend yield	0.40%	0.40%	0.40%
New York Stock Exchange Composite Index
Share-based Compensation Arrangement by Share-based Payment Award
Expected historical volatility	24.10%	22.70%	22.90%

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]	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Share-based Compensation Arrangement by Share-based Payment Award
Expected life (years)	4 years	4 years	5 years
Risk-free interest rate	3.80%	1.60%	0.40%
Volatility-historical	46.60%	43.70%	37.80%
Dividend yield	0.40%	0.40%	0.40%

Schedule of Stock Compensation

Schedule of Stock Compensation Plan Activity (Detail) - shares shares in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Share-based Compensation Arrangement by Share-based Payment Award
Awarded	728	660	447
Forfeited	(58)	(51)	(70)
Outstanding at January 1	188	171	216
Granted	41	42	34
Exercised	(56)	(25)	(78)
Forfeited	(2)		(1)
Outstanding at December 31	171	188	171
Vested and expected to vest at December 31	171	188	171
Exercisable at December 31	68	69	30
Restricted Stock Units
Share-based Compensation Arrangement by Share-based Payment Award
Non-vested at January 1	1,317	1,417	1,789
Awarded	728	660	447
Vested	(609)	(709)	(749)
Forfeited	(58)	(51)	(70)
Non-vested at December 31	1,378	1,317	1,417

Schedule of Share Based Compens

Schedule of Share Based Compensation Total Shares Available (Detail) - shares shares in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Share-Based Payment Arrangement [Abstract]
Available for grant at January 1	5,062	5,713	6,123
Options granted	(41)	(42)	(34)
Options forfeited	2		1
Restricted stock units awarded	(728)	(660)	(447)
Restricted stock units forfeited	58	51	70
Available for grant at December 31	4,353	5,062	5,713

Schedule of Weighted-Average Re

Schedule of Weighted-Average Restricted Stock Unit Award Fair Value (Detail) - $ / shares	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Share-Based Payment Arrangement [Abstract]
Non-vested at January 1	$ 88.71	$ 67.97	$ 47.84
Awarded	105.05	108.74	115.51
Vested	75.55	54.27	43.99
Forfeited	102.12	85.71	65.52
Non-vested at December 31	$ 101	$ 88.71	$ 67.97

Schedule of Restricted Stock Un

Schedule of Restricted Stock Unit Awards Aggregate Intrinsic Value (Detail) - Restricted Stock Units - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Share-based Compensation Arrangement by Share-based Payment Award
Vested	$ 62,001	$ 95,408	$ 101,679
Outstanding	149,504	115,087	231,763
Expected to vest	$ 135,238	$ 108,666	$ 231,246

Schedule of Restricted Stock _2

Schedule of Restricted Stock Units Weighted Average Remaining Contractual Terms (Detail) - Restricted Stock Units	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Share-based Compensation Arrangement by Share-based Payment Award
Outstanding	1 year 1 month 17 days	11 months 26 days	10 months 20 days
Expected to vest	1 year 1 month 17 days	11 months 26 days	10 months 20 days

Schedule of Weighted Average St

Schedule of Weighted Average Stock Options Exercise Price (Detail)	12 Months Ended
	Dec. 31, 2023 $ / shares
Share-Based Payment Arrangement [Abstract]
Outstanding at January 1	$ 76.52
Options granted	104.15
Options exercised	39.71
Options forfeited	112.57
Options cancelled	113.03
Outstanding at December 31	94.85
Exercisable at December 31	$ 81.53

Schedule of Stock Option Aggreg

Schedule of Stock Option Aggregated Intrinsic Value Information (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Share-Based Payment Arrangement [Abstract]
Exercised	$ 3,901	$ 2,030	$ 6,345
Outstanding	2,647	3,963	17,356
Expected to vest	696	1,583	13,500
Vested and exercisable	$ 1,950	$ 2,380	$ 3,856

Schedule of Stock Options Weigh

Schedule of Stock Options Weighted Average Remaining Contractual Terms (Detail)	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Share-Based Payment Arrangement [Abstract]
Outstanding	4 years 4 months 24 days	4 years 2 months 12 days	4 years 4 months 24 days
Expected to vest	5 years 1 month 6 days	4 years 9 months 18 days	4 years 9 months 18 days
Vested and exercisable	3 years 4 months 24 days	3 years 1 month 6 days	2 years 6 months

Stock Based Compensation (Detai

Stock Based Compensation (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Stock-based compensation	$ 57,682	$ 48,228	$ 45,643
Income tax benefit	(10,397)	(11,493)	(14,389)
Total stock-based compensation expense after income taxes	47,285	36,735	31,254
Cost Of Revenues
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Stock-based compensation	4,208	4,050	4,196
Engineering And Development
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Stock-based compensation	10,659	9,992	9,783
Selling and Administrative
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Stock-based compensation	$ 42,815	$ 34,186	$ 31,664

Savings Plan - Additional Infor

Savings Plan - Additional Information (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Savings Plan [Line Items]
Savings plan maximum percentage of employees contribution allowable	20%
Percentage of employer contributions vested per year	25%
Maximum employment period considered for vesting of employers' contribution, in years	4 years
Liability, Retirement and Postemployment Benefits	$ 55.9	$ 44.1
U.S. Qualified Pension Plan
Savings Plan [Line Items]
Maximum percentage of matching contributions made by the employer	100%	100%	100%
Percentage of employer match on employee contribution	4%	4%	4%
Savings Plan
Savings Plan [Line Items]
Amounts charged to statements of operations	$ 30.5	$ 30.1	$ 26.9

Schedule of Income (Loss) Befor

Schedule of Income (Loss) Before Income Taxes (Detail) - USD ($) $ in Thousands		12 Months Ended
		Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Income Tax Disclosure [Abstract]
U.S.		$ 307,997	$ 385,968	$ 403,451
Non-U.S.		217,575	454,417	757,504
Income before income taxes	[1],[2]	$ 525,572	$ 840,385	$ 1,160,955
[1] Included in Corporate and Eliminations are interest income, interest expense, net foreign exchange gains (losses), intercompany eliminations, pension and postretirement plan actuarial gains (losses), legal and environmental fees, contingent consideration adjustments, acquisition and divestiture related expenses, contract termination settlement charge, an expense for the modification of Teradyne's former chief executive officer's outstanding equity awards, and loss on convertible debt conversions in 2021. Included in income (loss) before taxes are charges and credits related to restructuring and other, inventory charges and loss on convertible debt conversions in 2021.

Schedule of Provision (Benefit)

Schedule of Provision (Benefit) for Income Taxes from Operations (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Income Tax Disclosure [Abstract]
Current, U.S. Federal	$ 58,063	$ 86,692	$ 58,218
Current, Non-U.S.	54,037	74,204	105,153
Current, State	2,362	2,681	300
Current, Total	114,462	163,577	163,671
Deferred, U.S. Federal	(27,459)	(36,739)	(15,106)
Deferred, Non-U.S.	(8,584)	1,232	(4,300)
Deferred, State	(1,599)	(3,186)	2,101
Deferred, Total	(37,642)	(38,693)	(17,305)
Total provision for income taxes	$ 76,820	$ 124,884	$ 146,366

Income Taxes - Additional Infor

Income Taxes - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Thousands			3 Months Ended	12 Months Ended
	Dec. 15, 2022	Aug. 16, 2022	Dec. 31, 2021	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2017	Dec. 31, 2020
Income Taxes [Line Items]
Total (benefit) provision for income taxes				$ 76,820	$ 124,884	$ 146,366
Effective tax rate				14.60%	14.90%	12.60%
Tax savings due to the tax holiday				$ 1,400	$ 16,000	$ 33,300
Tax savings due to the tax holiday, per share				$ 0.01	$ 0.09	$ 0.18
Tax holiday expiration date				December 31, 2025
Valuation allowance includes net deferred tax assets				$ 109,251	$ 103,807
Tax credit carryforwards, approximately							$ 147,100
Tax credits carryforwards				112,571	105,503
Reduction in unrecognized tax benefits			$ 14,465	18,606	15,608	$ 14,465		$ 17,903
Unrecognized tax benefits, if recognized would impact effective tax rate				12,900
Unrecognized tax benefits, if recognized would impact deferred taxes				5,700
Decrease in unrecognised tax benefit due to lapse in statute of limitation				0	212	3,246
Reasonably possible decrease of unrecognized tax benefit				2,800
Accrued interest and penalties				1,300	400
Interest and penalties related to income tax, expense (benefit)				900	$ 100	$ 900
Expected future payments related transition tax in 2024				14,800
Expense related to remeasurement of deferred tax assets and liabilities				59,100
Expected future payments related transition tax in one to three years				44,300
Percentage of alternative minimum tax		15%
Minimum effective tax rate	15%
InterCompany Cost Sharing Arrangement [Member]
Income Taxes [Line Items]
Total (benefit) provision for income taxes			$ (2,500)
United States
Income Taxes [Line Items]
Tax credits carryforwards, business							$ 3,400
Tax credit carryforward, expiration date							2028
State and Local Jurisdiction
Income Taxes [Line Items]
Tax credits carryforwards							$ 143,800
Reduction in unrecognized tax benefits				$ 18,600
State and Local Jurisdiction | Earliest Tax Year
Income Taxes [Line Items]
Tax credit carryforward, expiration date							2023
State and Local Jurisdiction | Latest Tax Year
Income Taxes [Line Items]
Tax credit carryforward, expiration date							2043
State and Local Jurisdiction | Do Not Expire
Income Taxes [Line Items]
Tax credits carryforwards							$ 76,500

Schedule of Reconciliation of E

Schedule of Reconciliation of Effective Tax Rate (Detail)	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Income Tax Disclosure [Abstract]
U.S. statutory federal tax rate	21%	21%	21%
Foreign taxes	2.50%	(1.90%)	(4.50%)
Non-deductible officers' compensation	1.10%	1.30%	0.80%
U.S. global intangible low-taxed income	0.80%	1.20%	0.60%
State income taxes, net of federal tax benefit	0.10%	(0.10%)	0.20%
U.S. research and development credit	(4.20%)	(1.80%)	(1.40%)
U.S. foreign derived intangible income	(3.90%)	(3.10%)	(2.30%)
Foreign tax credits	(3.30%)	(1.00%)	(0.50%)
Equity compensation	(0.40%)	(1.10%)	(1.00%)
Other, net	0.90%	0.40%	(0.30%)
Effective tax rate, Total	14.60%	14.90%	12.60%

Schedule of Components of Defer

Schedule of Components of Deferred Tax Assets Liabilities (Detail) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Income Tax Disclosure [Abstract]
Tax credits	$ 112,571	$ 105,503
Research and development	82,571	47,760
Accruals	25,644	30,747
Pension liabilities	24,997	21,335
Lease liabilities	21,167	18,679
Inventory valuations	19,289	22,554
Deferred revenue	13,807	14,909
Equity compensation	7,179	6,578
Vacation accrual	6,096	5,856
Net operating loss carryforwards	5,737	1,857
Investment impairment	3,292	3,292
Intangible assets	2,323	350
Marketable securities	128	2,283
Other	953	2,520
Gross deferred tax assets	325,754	284,223
Less: valuation allowance	(109,251)	(103,807)
Total deferred tax assets	216,503	180,416
Right of use assets	(19,016)	(16,607)
Depreciation	(16,681)	(19,078)
Contingent consideration	(5,214)	(5,214)
Total deferred tax liabilities	(40,911)	(40,899)
Net deferred assets	$ 175,592	$ 139,517

Summary of Operating Loss Carry

Summary of Operating Loss Carryforwards (Detail) $ in Thousands	Dec. 31, 2023 USD ($)
Operating Loss Carryforwards [Line Items]
U.S. Federal Operating Loss Carryforwards	$ 215
Foreign Operating Loss Carryforwards	5,522
2024
Operating Loss Carryforwards [Line Items]
U.S. Federal Operating Loss Carryforwards	6
2025
Operating Loss Carryforwards [Line Items]
U.S. Federal Operating Loss Carryforwards	4
2026
Operating Loss Carryforwards [Line Items]
U.S. Federal Operating Loss Carryforwards	0
2027
Operating Loss Carryforwards [Line Items]
U.S. Federal Operating Loss Carryforwards	0
2028
Operating Loss Carryforwards [Line Items]
U.S. Federal Operating Loss Carryforwards	23
Foreign Operating Loss Carryforwards	83
2029-2033
Operating Loss Carryforwards [Line Items]
U.S. Federal Operating Loss Carryforwards	121
Foreign Operating Loss Carryforwards	500
2034-2038
Operating Loss Carryforwards [Line Items]
U.S. Federal Operating Loss Carryforwards	31
Beyond 2038
Operating Loss Carryforwards [Line Items]
U.S. Federal Operating Loss Carryforwards	0
Non-Expiring
Operating Loss Carryforwards [Line Items]
U.S. Federal Operating Loss Carryforwards	30
Foreign Operating Loss Carryforwards	$ 4,939

Schedule of Unrecognized Tax Be

Schedule of Unrecognized Tax Benefits (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Income Tax Disclosure [Line Items]
Beginning balance, as of January 1	$ 15,608	$ 14,465	$ 17,903
Tax positions for current year, Additions	0	1,398	1,417
Tax positions for prior years, Additions	3,024	13	30
Tax positions for prior years, Reductions	(26)	(56)	(1,639)
Expiration of statutes, Reductions	0	(212)	(3,246)
Ending balance as of December 31	$ 18,606	$ 15,608	$ 14,465

Operating Segment, Geographic_3

Operating Segment, Geographic and Significant Customer Information - Additional Information (Detail) - Segment	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Segment Reporting Information [Line Items]
Operating segments	4
Qualcomm | Consolidated Revenue | Customer Concentration Risk
Segment Reporting Information [Line Items]
Concentration risk, percentage		11%
Semiconductor Test | Consolidated Revenue | Customer Concentration Risk
Segment Reporting Information [Line Items]
Concentration risk, percentage			19%
Semiconductor Test | Customer 1 | Consolidated Revenue | Revenue from Rights Concentration Risk
Segment Reporting Information [Line Items]
Concentration risk, percentage	10%		12%

Schedule of Segment Information

Schedule of Segment Information (Detail) - USD ($) $ in Thousands		12 Months Ended
		Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Segment Reporting Information [Line Items]
Revenues	[1],[2]	$ 2,676,298	$ 3,155,045	$ 3,702,881
Income (loss) before taxes	[3],[4]	525,572	840,385	1,160,955
Total assets	[5]	3,486,824	3,501,252	3,809,425
Property additions		159,642	163,249	132,472
Depreciation and amortization expense		110,886	110,675	125,485
System Test
Segment Reporting Information [Line Items]
Revenues	[1]	338,197	469,346	467,739
Wireless Test
Segment Reporting Information [Line Items]
Revenues	[1]	144,282	201,720	216,895
Operating Segments
Segment Reporting Information [Line Items]
Revenues		2,676,298	3,154,794	3,702,881
Income (loss) before taxes	[3],[4]	523,710	851,943	1,215,428
Total assets	[5]	2,317,220	2,308,484	2,225,259
Property additions		159,642	163,249	132,472
Depreciation and amortization expense		111,116	110,097	112,529
Operating Segments | Semiconductor Test
Segment Reporting Information [Line Items]
Revenues		1,818,636	2,080,590	2,642,342
Income (loss) before taxes	[3],[4]	453,320	634,488	976,988
Total assets	[5]	1,329,522	1,382,623	1,245,596
Property additions		113,415	126,898	115,618
Depreciation and amortization expense		77,745	76,532	75,982
Operating Segments | System Test
Segment Reporting Information [Line Items]
Revenues		338,197	469,346	467,739
Income (loss) before taxes	[3],[4]	94,073	166,879	163,064
Total assets	[5]	182,084	165,925	170,954
Property additions		3,643	7,275	3,905
Depreciation and amortization expense		3,801	3,235	3,156
Operating Segments | Robotics
Segment Reporting Information [Line Items]
Revenues		375,183	403,138	375,905
Income (loss) before taxes	[3],[4]	(54,251)	(16,244)	(8,167)
Total assets	[5]	737,323	665,638	701,196
Property additions		40,739	25,712	9,821
Depreciation and amortization expense		25,527	25,339	27,336
Operating Segments | Wireless Test
Segment Reporting Information [Line Items]
Revenues		144,282	201,720	216,895
Income (loss) before taxes	[3],[4]	30,568	66,820	83,543
Total assets	[5]	68,291	94,298	107,513
Property additions		1,845	3,364	3,128
Depreciation and amortization expense		4,043	4,991	6,055
Corporate and Eliminations
Segment Reporting Information [Line Items]
Revenues			(251)
Income (loss) before taxes	[3],[4]	(1,862)	11,558	54,473
Total assets	[5]	(1,169,604)	(1,192,768)	(1,584,166)
Depreciation and amortization expense		$ (230)	$ (578)	$ (12,956)
[1] Includes $ 5.2 m illion, $ 8.2 million and $ 13.2 million in 2023, 2022 and 2021, respectively, for leases of Teradyne’s systems recognized outside of ASC 606: “Revenue from Contracts with Customers.” Revenues attributable to a country are based on location of customer site. Included in Corporate and Eliminations are interest income, interest expense, net foreign exchange gains (losses), intercompany eliminations, pension and postretirement plan actuarial gains (losses), legal and environmental fees, contingent consideration adjustments, acquisition and divestiture related expenses, contract termination settlement charge, an expense for the modification of Teradyne's former chief executive officer's outstanding equity awards, and loss on convertible debt conversions in 2021. Included in income (loss) before taxes are charges and credits related to restructuring and other, inventory charges and loss on convertible debt conversions in 2021. Total assets are attributable to each segment. Semiconductor Test includes $ 34.8 million of total assets classified as assets held for sale. See Note E: “Assets held for sale” for additional information. Corporate assets consist of cash and cash equivalents, marketable securities and certain other assets.

Schedule of Segment Informati_2

Schedule of Segment Information (Parenthetical) (Detail) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Segment Reporting Information [Line Items]
Assets held for sale	$ 11,531	$ 0
Semiconductor Test | Operating Segments
Segment Reporting Information [Line Items]
Assets held for sale	$ 34,800	$ 34,800	$ 34,800

Schedule of Segment Reporting I

Schedule of Segment Reporting Information by Segment Charges (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Segment Reporting Information [Line Items]
Restructuring and other—employee severance	$ 21,277	$ 17,185	$ 9,312
Other (income) expense, net - gain on foreign exchange option	(10,900)	(10,800)	2,100
Restructuring and other—gain on sale of asset	0	3,410	0
Other (income) expense, net—loss on convertible debt conversion	962	5,786	(24,572)
Restructuring and other - AutoGuide contingent consideration adjustment	0	0	(7,227)
Mobile Industrial Robots (MiR)
Segment Reporting Information [Line Items]
Restructuring and other - AutoGuide contingent consideration adjustment			7,200
Semiconductor Test
Segment Reporting Information [Line Items]
Cost of revenues—inventory charge	22,482	21,456	6,661
Restructuring and other—employee severance	5,666	0	0
Restructuring and other - acquisition & divestiture related expenses			500
Restructuring and other—environmental and legal liabilities			2,500
System Test
Segment Reporting Information [Line Items]
Cost of revenues—inventory charge	1,855	1,730	641
Restructuring and other—employee severance	1,541	0	0
Robotics
Segment Reporting Information [Line Items]
Cost of revenues—inventory charge	2,275	3,668	6,403
Restructuring and other—employee severance	3,707	2,115	1,210
Restructuring and other - acquisition & divestiture related expenses	0	0	1,000
Wireless Test
Segment Reporting Information [Line Items]
Cost of revenues—inventory charge	1,746	4,598	1,770
Corporate And Eliminations
Segment Reporting Information [Line Items]
Selling and administrative—equity modification charge	5,889	0	0
Restructuring and other—employee severance	3,599	0	0
Restructuring and other - acquisition & divestiture related expenses	3,562	0	(513)
Restructuring and other-contract termination	1,511	0	0
Restructuring and other—environmental and legal liabilities	1,100	2,700	1,971
Other (income) expense, net - gain on foreign exchange option	(7,464)	0	0
Restructuring and other—legal settlement charge	0	14,700	12,000
Restructuring and other—gain on sale of asset	0	(3,410)	0
Other (income) expense, net—loss on convertible debt conversion	0	0	28,828
Restructuring and other - AutoGuide contingent consideration adjustment	$ 0	$ 0	$ (7,227)

Schedule of Revenues by Country

Schedule of Revenues by Country (Detail) - USD ($) $ in Thousands		12 Months Ended
		Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenues	[1],[2]	$ 2,676,298	$ 3,155,045	$ 3,702,881
UNITED STATES
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenues	[2]	433,661	469,948	392,626
KOREA
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenues	[2]	394,690	544,816	502,167
TAIWAN
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenues	[2]	384,842	626,424	1,117,874
CHINA
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenues	[2]	314,899	491,798	631,963
JAPAN
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenues	[2]	281,742	162,920	166,231
Europe
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenues	[2]	273,784	268,384	259,954
PHILIPPINES
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenues	[2]	189,419	124,107	166,838
SINGAPORE
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenues	[2]	116,969	99,503	121,582
THAILAND
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenues	[2]	91,818	137,356	138,812
MALAYSIA
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenues	[2]	89,197	142,203	136,774
Rest Of The World
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenues	[2]	$ 105,277	$ 87,586	$ 68,060
[1] Includes $ 5.2 m illion, $ 8.2 million and $ 13.2 million in 2023, 2022 and 2021, respectively, for leases of Teradyne’s systems recognized outside of ASC 606: “Revenue from Contracts with Customers.” Revenues attributable to a country are based on location of customer site.

Schedule of Long-Lived Assets b

Schedule of Long-Lived Assets by Geographic Area (Detail) - USD ($) $ in Thousands		Dec. 31, 2023	[1]	Dec. 31, 2022
Revenues from External Customers and Long-Lived Assets [Line Items]
Long-lived assets		$ 530,440		$ 492,417
UNITED STATES
Revenues from External Customers and Long-Lived Assets [Line Items]
Long-lived assets		322,445		328,341
Foreign
Revenues from External Customers and Long-Lived Assets [Line Items]
Long-lived assets	[2]	$ 207,995		$ 164,076
[1] Includes $ 11.5 million of long-lived assets classified as assets held for sale. See Note E: “Assets held for sale” for additional information. As of December 31, 2023 and December 31, 2022, long-lived assets attributable to Denmark were $ 78.1 million and $ 42.5 million, respectively.

Schedule of Long-Lived Assets_2

Schedule of Long-Lived Assets by Geographic Area (Parenthetical) (Detail) - USD ($) $ in Thousands		Dec. 31, 2023		Dec. 31, 2022
Revenues from External Customers and Long-Lived Assets [Line Items]
Long-lived assets		$ 530,440	[1]	$ 492,417
Assets held for sale		11,531		0
UNITED STATES
Revenues from External Customers and Long-Lived Assets [Line Items]
Long-lived assets		322,445	[1]	328,341
Assets held for sale		11,500
DENMARK
Revenues from External Customers and Long-Lived Assets [Line Items]
Long-lived assets		78,100		42,500
Foreign
Revenues from External Customers and Long-Lived Assets [Line Items]
Long-lived assets	[2]	207,995	[1]	$ 164,076
Assets held for sale		$ 11,500
[1] Includes $ 11.5 million of long-lived assets classified as assets held for sale. See Note E: “Assets held for sale” for additional information. As of December 31, 2023 and December 31, 2022, long-lived assets attributable to Denmark were $ 78.1 million and $ 42.5 million, respectively.

Stock Repurchase Program - Addi

Stock Repurchase Program - Additional Information (Detail) - USD ($) $ / shares in Units, shares in Millions, $ in Millions		12 Months Ended
	Jan. 01, 2022	Dec. 31, 2023	Dec. 31, 2022	Jan. 31, 2023
Disclosure of Repurchase Agreements [Abstract]
Cumulative repurchases, shares	7.3	3.9	12
Cumulative repurchases, value	$ 752.1	$ 400.5	$ 1,352.1	$ 2,000
Common stock average price	$ 103.69	$ 102.47	$ 112.44

Subsequent Events - Additional

Subsequent Events - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Thousands	1 Months Ended	12 Months Ended
	Jan. 31, 2024	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Subsequent Event [Line Items]
Share-Based Payment Arrangement, Expense		$ 57,682	$ 48,228	$ 45,643
Subsequent Event
Subsequent Event [Line Items]
Cash Dividends payable, amount per share increase percentage	9%
Cash Dividends payable, amount per share	$ 0.12
Cash Dividends payable, date to be paid	Mar. 15, 2024
Cash Dividends payable, record date	Feb. 16, 2024

Valuation and Qualifying Acco_2

Valuation and Qualifying Accounts (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Allowance for Credit Losses
Valuation and Qualifying Accounts Disclosure [Line Items]
Balance at Beginning of Period	$ 1,955	$ 2,012	$ 2,034
Additions Charged to Cost and Expenses	301	500	500
Other	23	(6)	(27)
Deductions	291	551	495
Balance at End of Period	1,988	1,955	2,012
Valuation Allowance of Deferred Tax Assets
Valuation and Qualifying Accounts Disclosure [Line Items]
Balance at Beginning of Period	103,807	97,170	84,962
Additions Charged to Cost and Expenses	5,759	7,652	13,502
Other	59	21	0
Deductions	374	1,036	1,294
Balance at End of Period	$ 109,251	$ 103,807	$ 97,170