National Instruments (NATI) 10-Q 1 Nov 21 2021 Q3 Quarterly report Financial data

Cover

Cover - shares	9 Months Ended
	Sep. 30, 2021	Oct. 28, 2021
Cover [Abstract]
Document Type	10-Q
Document Quarterly Report	true
Document Period End Date	Sep. 30, 2021
Document Transition Report	false
Entity File Number	000-25426
Entity Registrant Name	NATIONAL INSTRUMENTS CORP
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	74-1871327
Entity Address, Address Line One	11500 North MoPac Expressway
Entity Address, City or Town	Austin,
Entity Address, State or Province	TX
Entity Address, Postal Zip Code	78759
City Area Code	512
Local Phone Number	683-0100
Title of 12(b) Security	Common Stock, $0.01 par value
Trading Symbol	NATI
Security Exchange Name	NASDAQ
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Large Accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
Entity Shell Company	false
Entity Common Stock, Shares Outstanding (in shares)		131,881,802
Entity Central Index Key	0000935494
Current Fiscal Year End Date	--12-31
Document Fiscal Year Focus	2021
Document Fiscal Period Focus	Q3
Amendment Flag	false

Consolidated Balance Sheets

Consolidated Balance Sheets - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Assets
Cash and cash equivalents	$ 230,697	$ 260,232
Short-term investments	0	59,923
Accounts receivable, net	279,196	266,869
Inventories, net	236,733	194,012
Prepaid expenses and other current assets	89,152	68,470
Total current assets	835,778	849,506
Property and equipment, net	248,712	254,399
Goodwill	480,489	467,547
Intangible assets, net	136,938	172,719
Operating lease right-of-use assets	56,644	67,674
Other long-term assets	79,850	72,643
Total assets	1,838,411	1,884,488
Liabilities and stockholders' equity
Accounts payable and accrued expenses	63,568	51,124
Accrued compensation	87,802	87,068
Deferred revenue - current	120,762	132,151
Operating lease liabilities - current	12,360	15,801
Other taxes payable	43,673	48,129
Debt, current	0	5,000
Other current liabilities	25,162	42,578
Total current liabilities	353,327	381,851
Deferred income taxes	26,023	25,288
Income tax payable - non-current	54,195	61,623
Deferred revenue - non-current	32,278	36,335
Operating lease liabilities - non-current	29,206	35,854
Debt, non-current	100,000	92,036
Other long-term liabilities	16,910	26,630
Total liabilities	611,939	659,617
Commitments and contingencies
Stockholders' equity:
Preferred stock:  par value $0.01;  5,000,000 shares authorized; none issued and outstanding	0	0
Common stock:  par value $0.01;  360,000,000 shares authorized; 132,622,234 shares and 131,246,615 shares issued and outstanding, respectively	1,326	1,312
Additional paid-in capital	1,109,918	1,033,284
Retained earnings	132,404	211,101
Accumulated other comprehensive loss	(17,176)	(20,826)
Total stockholders’ equity	1,226,472	1,224,871
Total liabilities and stockholders’ equity	$ 1,838,411	$ 1,884,488

Consolidated Balance Sheets (Pa

Consolidated Balance Sheets (Parenthetical) - $ / shares	Sep. 30, 2021	Dec. 31, 2020
Statement of Financial Position [Abstract]
Preferred stock, par value per share (in usd per share)	$ 0.01	$ 0.01
Preferred stock, authorized (in shares)	5,000,000	5,000,000
Preferred stock, issued (in shares)	0	0
Preferred stock, outstanding (in shares)	0	0
Common stock, par value per share (in usd per share)	$ 0.01	$ 0.01
Common stock, authorized (in shares)	360,000,000	360,000,000
Common stock, issued (in shares)	132,622,234	131,246,615
Common stock, outstanding (in shares)	132,622,234	131,246,615

Consolidated Statements Of Inco

Consolidated Statements Of Income - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Net sales:
Total net sales	$ 367,162	$ 308,124	$ 1,049,040	$ 918,834
Cost of sales:
Total cost of sales	102,715	92,263	297,367	261,925
Gross profit	264,447	215,861	751,673	656,909
Operating expenses:
Sales and marketing	117,065	109,774	345,048	330,939
Research and development	82,165	70,802	243,685	206,648
General and administrative	31,037	37,431	94,672	92,980
Total operating expenses	230,267	218,007	683,405	630,567
Gain on sale of business/assets	0	0	0	159,753
Operating income	34,180	(2,146)	68,268	186,095
Other expense	(1,820)	(2,001)	(9,851)	(2,584)
Income before income taxes	32,360	(4,147)	58,417	183,511
Provision for income taxes	5,183	475	9,438	44,588
Net income (loss)	$ 27,177	$ (4,622)	$ 48,979	$ 138,923
Basic earnings per share (in usd per share)	$ 0.20	$ (0.04)	$ 0.37	$ 1.06
Weighted average shares outstanding - basic (in shares)	133,031	131,419	132,657	131,017
Diluted earnings per share (in usd per share)	$ 0.20	$ (0.04)	$ 0.37	$ 1.06
Weighted average shares outstanding - diluted (in shares)	133,686	131,419	133,829	131,671
Dividends declared per share (in usd per share)	$ 0.27	$ 0.26	$ 0.81	$ 0.78
Product
Net sales:
Total net sales	$ 325,724	$ 269,651	$ 927,307	$ 809,890
Cost of sales:
Total cost of sales	99,072	88,370	286,485	254,236
Software maintenance
Net sales:
Total net sales	41,438	38,473	121,733	108,944
Cost of sales:
Total cost of sales	$ 3,643	$ 3,893	$ 10,882	$ 7,689

Consolidated Statements Of Comp

Consolidated Statements Of Comprehensive Income - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Statement of Comprehensive Income [Abstract]
Net income (loss)	$ 27,177	$ (4,622)	$ 48,979	$ 138,923
Other comprehensive (loss) income, before tax and net of reclassification adjustments:
Foreign currency translation adjustment	(5,675)	8,483	(10,585)	6,507
Unrealized loss on securities available-for-sale	(21)	(163)	(162)	(317)
Unrealized gain (loss) on derivative instruments	4,243	(9,530)	18,605	(10,128)
Other comprehensive income (loss), before tax	(1,453)	(1,210)	7,858	(3,938)
Tax expense (benefit) related to items of other comprehensive income	948	(2,335)	4,208	(2,268)
Other comprehensive (loss) income, net of tax	(2,401)	1,125	3,650	(1,670)
Comprehensive income (loss)	$ 24,776	$ (3,497)	$ 52,629	$ 137,253

Consolidated Statements Of Cash

Consolidated Statements Of Cash Flows - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020
Cash flow from operating activities:
Net income	$ 48,979	$ 138,923
Adjustments to reconcile net income to net cash provided by operating activities:
Disposal gain on sale of business/assets	0	(159,753)
Depreciation and amortization	73,418	61,228
Stock-based compensation	56,064	42,556
Loss from equity-method investees	5,082	2,559
Deferred income taxes	(2,030)	(932)
Changes in operating assets and liabilities	(95,477)	24,203
Net cash provided by operating activities	86,036	108,784
Cash flow from investing activities:
Acquisitions, net of cash received	(19,784)	(334,981)
Capital expenditures	(26,147)	(36,573)
Proceeds from sale of assets/business, net of cash divested	0	160,266
Capitalization of internally developed software	(1,246)	(2,806)
Additions to other intangibles	(2,317)	(1,045)
Payments to acquire equity-method investments	(15,753)	(7,502)
Purchases of short-term investments	0	(206,330)
Sales and maturities of short-term investments	59,714	351,597
Net cash used in investing activities	(5,533)	(77,374)
Cash flow from financing activities:
Proceeds from revolving line of credit	100,000	20,000
Proceeds from term loan	0	70,000
Payments on term loan	(98,750)	(875)
Debt issuance costs	(1,993)	(1,480)
Proceeds from issuance of common stock	25,438	24,971
Repurchase of common stock	(25,000)	(39,244)
Dividends paid	(107,397)	(102,396)
Net cash used in financing activities	(107,702)	(29,024)
Effect of exchange rate changes on cash	(2,336)	317
Net change in cash and cash equivalents	(29,535)	2,703
Cash and cash equivalents at beginning of period	260,232	194,616
Cash and cash equivalents at end of period	$ 230,697	$ 197,319

Consolidated Statements Of Stoc

Consolidated Statements Of Stockholders' Equity - USD ($) $ in Thousands		Total	Common Stock	Additional-Paid in Capital	Retained Earnings	Accumulated Other Comprehensive Income/(Loss)
Beginning Balance (in shares) at Dec. 31, 2019			130,504,535
Beginning Balance at Dec. 31, 2019		$ 1,176,350	$ 1,305	$ 953,578	$ 242,537	$ (21,070)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income (loss)		138,923			138,923
Other comprehensive income (loss), net of tax		(1,670)				(1,670)
Issuance of common stock under employee plans (in shares)			1,855,806
Issuance of common stock under employee plans		24,971	$ 18	24,953
Stock-based compensation		42,264		42,264
Repurchase of common stock (in shares)			(1,114,701)
Repurchase of common stock		(39,244)	$ (11)	(8,139)	(31,094)
Dividends paid	[1]	(102,396)			(102,396)
Ending Balance (in shares) at Sep. 30, 2020			131,245,640
Ending Balance at Sep. 30, 2020		1,239,198	$ 1,312	1,012,656	247,970	(22,740)
Beginning Balance (in shares) at Jun. 30, 2020			131,436,108
Beginning Balance at Jun. 30, 2020		1,269,639	$ 1,314	993,058	299,132	(23,865)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income (loss)		(4,622)			(4,622)
Other comprehensive income (loss), net of tax		1,125				1,125
Issuance of common stock under employee plans (in shares)			256,034
Issuance of common stock under employee plans		7,717	$ 2	7,715
Stock-based compensation		15,142		15,142
Repurchase of common stock (in shares)			(446,502)
Repurchase of common stock		(15,563)	$ (4)	(3,259)	(12,300)
Dividends paid	[1]	(34,240)			(34,240)
Ending Balance (in shares) at Sep. 30, 2020			131,245,640
Ending Balance at Sep. 30, 2020		$ 1,239,198	$ 1,312	1,012,656	247,970	(22,740)
Beginning Balance (in shares) at Dec. 31, 2020		131,246,615	131,246,615
Beginning Balance at Dec. 31, 2020		$ 1,224,871	$ 1,312	1,033,284	211,101	(20,826)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income (loss)		48,979			48,979
Other comprehensive income (loss), net of tax		3,650				3,650
Issuance of common stock under employee plans (in shares)			1,974,685
Issuance of common stock under employee plans		25,438	$ 20	25,418
Stock-based compensation		55,931		55,931
Repurchase of common stock (in shares)			(599,066)
Repurchase of common stock		(25,000)	$ (6)	(4,715)	(20,279)
Dividends paid	[2]	$ (107,397)			(107,397)
Ending Balance (in shares) at Sep. 30, 2021		132,622,234	132,622,234
Ending Balance at Sep. 30, 2021		$ 1,226,472	$ 1,326	1,109,918	132,404	(17,176)
Beginning Balance (in shares) at Jun. 30, 2021			132,980,932
Beginning Balance at Jun. 30, 2021		1,235,652	$ 1,330	1,087,622	161,475	(14,775)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income (loss)		27,177			27,177
Other comprehensive income (loss), net of tax		(2,401)				(2,401)
Issuance of common stock under employee plans (in shares)			240,368
Issuance of common stock under employee plans		8,199	$ 2	8,197
Stock-based compensation		18,814		18,814
Repurchase of common stock (in shares)			(599,066)
Repurchase of common stock		(25,000)	$ (6)	(4,715)	(20,279)
Dividends paid	[2]	$ (35,969)			(35,969)
Ending Balance (in shares) at Sep. 30, 2021		132,622,234	132,622,234
Ending Balance at Sep. 30, 2021		$ 1,226,472	$ 1,326	$ 1,109,918	$ 132,404	$ (17,176)
[1]	Cash dividends declared per share of common stock were $0.26 for the three months ended September 30, 2020, and $0.78 for the nine months ended September 30, 2020.
[2]	Cash dividends declared per share of common stock were $0.27 for the three months ended September 30, 2021, and $0.81 for the nine months ended September 30, 2021.

Consolidated Statements Of St_2

Consolidated Statements Of Stockholders' Equity (Parenthetical) - $ / shares	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Statement of Stockholders' Equity [Abstract]
Dividends declared per share (in usd per share)	$ 0.27	$ 0.26	$ 0.81	$ 0.78

Basis of presentation

Basis of presentation	9 Months Ended
	Sep. 30, 2021
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Basis of presentation	Basis of presentation The accompanying unaudited consolidated financial statements should be read in conjunction with the consolidated financial statements and notes thereto for the fiscal year ended December 31, 2020, included in our Annual Report on Form 10-K filed with the Securities and Exchange Commission ("SEC") on February 23, 2021 (the "Form 10-K"). In our opinion, the accompanying consolidated financial statements reflect all adjustments (consisting only of normal recurring items) considered necessary to present fairly our financial position at September 30, 2021 and December 31, 2020, the results of our operations and comprehensive income for three and nine months ended September 30, 2021 and 2020, our cash flows for the nine months ended September 30, 2021 and 2020 and our statement of stockholders' equity for the three and nine months ended September 30, 2021 and 2020. Our operating results for the three and nine months ended September 30, 2021 are not necessarily indicative of the results that may be expected for the year ending December 31, 2021. These financial statements have been prepared in accordance with accounting principles generally accepted in the United States. Reclassifications Certain reclassifications have been made to prior period amounts to conform to the current period presentation. Recently Adopted Accounting Pronouncements Clarification of Equity Method Transition In January 2020, the Financial Accounting Standards Board ("FASB") issued Accounting Standards Update ("ASU") 2020-01, “Investments-Equity Securities (Topic 321), Investments-Equity Method and Joint Ventures (Topic 323), and Derivatives and Hedging (Topic 815): Clarifying the Interactions between Topic 321, Topic 323, and Topic 815,” which clarifies the interaction of the accounting for equity investments under Topic 321 and investments accounted for under the equity method of accounting in Topic 323 and the accounting for certain forward contracts and purchased options accounted for under Topic 815. The standard is effective for public companies for fiscal years, and interim periods within those fiscal years, beginning after December 15, 2020. We adopted ASU 2020-01 on January 1, 2021, and the new standard did not have a material impact on our consolidated financial statements and related disclosures. Recently Issued Accounting Pronouncements Although there are several other accounting pronouncements recently issued by the FASB, we do not expect the adoption of any of these accounting pronouncements had or will have a material impact on our consolidated financial statements. Summary of Significant Accounting Policies There were no changes in our significant accounting policies during the three and nine months ended September 30, 2021 compared to the significant accounting policies described in our Form 10-K. Divestitures AWR On January 15, 2020, we completed the sale of our AWR Corporation subsidiary ("AWR") for approximately $161 million. We recognized a gain of approximately $160 million on the sale. The gain is included within "Gain on sale of business/assets" in the consolidated statements of income, which also included approximately $1 million of transaction costs. The divestiture of AWR resulted in the derecognition of the following assets and liabilities: (In thousands) Cash $ 1,027 Accounts receivable, net 7,233 Prepaid and other current assets 283 Goodwill 7,221 Other non-current assets 556 Total Assets 16,320 Deferred revenue 15,296 Other current liabilities 940 Cumulative translation adjustment (660) Total liabilities and stockholders' equity 15,576 Total assets divested, net (including cash) $ 744 Other (Expense) Income Other expense, net consisted of the following amounts: Three Months Ended September 30, Nine Months Ended September 30, (In thousands) (Unaudited) (Unaudited) 2021 2020 2021 2020 Interest income $ 56 $ 414 $ 330 $ 3,724 Interest expense (657) (973) (2,584) (1,115) Gain (loss) from equity-method investments 278 (627) (5,082) (2,559) Net foreign exchange loss (1,226) (676) (2,681) (2,019) Other (271) (139) 166 (615) Other expense, net $ (1,820) $ (2,001) $ (9,851) $ (2,584) Earnings Per Share Basic earnings per share (“EPS”) is computed by dividing net income by the weighted average number of common shares outstanding during each period. Diluted EPS is computed by dividing net income by the weighted average number of common shares and common share equivalents outstanding (if dilutive) during each period. The number of common share equivalents, which includes restricted stock units ("RSUs"), is computed using the treasury stock method. The reconciliation of the denominators used to calculate basic EPS and diluted EPS for the three and nine months ended September 30, 2021 and 2020 are as follows (in thousands): Three Months Ended September 30, Nine Months Ended September 30, (Unaudited) (Unaudited) 2021 2020 2021 2020 Weighted average shares outstanding-basic 133,031 131,419 132,657 131,017 Plus: Common share equivalents RSUs 655 — 1,172 654 Weighted average shares outstanding-diluted 133,686 131,419 133,829 131,671 Shares issuable upon vesting of RSU awards of 143,000 shares and 3,490,700 shares for the three months ended September 30, 2021 and 2020, respectively, and 123,000 shares and 276,000 shares for the nine months ended September 30, 2021 and 2020, respectively, were excluded in the computations of diluted EPS because the effect of including the stock awards would have been anti-dilutive. Other Current Liabilities Other current liabilities on our consolidated balance sheet includes the following amounts: As of September 30, 2021 As of December 31, (In thousands) (unaudited) 2020 Income taxes payable - current $ 2,590 $ 13,720 Hedge payable - current 6,058 13,031 Other 16,514 15,827 Total $ 25,162 $ 42,578

Revenue

Revenue	9 Months Ended
	Sep. 30, 2021
Revenue from Contract with Customer [Abstract]
Revenue	Revenue Revenue Recognition Revenue is recognized upon transfer of control of the promised products or services to customers in an amount that reflects the consideration we expect to receive in exchange for those products or services. We enter into contracts that can include various combinations of our products or services, which are generally capable of being distinct and accounted for as separate performance obligations. Revenue is recognized net of allowances for returns and any taxes collected from customers, which are subsequently remitted to governmental authorities. Disaggregation of Revenues We disaggregate revenue from contracts with customers based on the timing of transfer of goods or services to customers (point-in-time or over time) and geographic region based on the billing location of the customer. We sell our products in the following three geographic regions: the Americas; Europe, Middle East and Africa region ("EMEA"); and Asia-Pacific region ("APAC"). Total net sales based on the disaggregation criteria described above are as follows: Three Months Ended September 30, (In thousands) (Unaudited) 2021 2020 Net sales: Point-in-Time (1) Over Time Total Point-in-Time (1) Over Time Total Americas $ 125,069 $ 23,835 $ 148,904 $ 107,808 $ 19,241 $ 127,049 EMEA 72,430 22,433 94,863 57,988 20,551 78,539 APAC 112,931 10,464 123,395 92,050 10,486 102,536 Total net sales (1) $ 310,430 $ 56,732 $ 367,162 $ 257,846 $ 50,278 $ 308,124 (1) Net sales contains hedging gains and losses, which do not represent revenues recognized from customers. Nine Months Ended September 30, (In thousands) (Unaudited) 2021 2020 Net sales: Point-in-Time (1) Over Time Total Point-in-Time (1) Over Time Total Americas $ 341,870 $ 68,436 $ 410,306 $ 316,220 $ 57,554 $ 373,774 EMEA 204,786 64,769 269,555 181,330 58,594 239,924 APAC 337,455 31,724 369,179 274,341 30,795 305,136 Total net sales (1) $ 884,111 $ 164,929 $ 1,049,040 $ 771,891 $ 146,943 $ 918,834 (1) Net sales contains hedging gains and losses, which do not represent revenues recognized from customers. Information about Contract Balances Amounts collected in advance of services being provided are accounted for as deferred revenue. Nearly all of our deferred revenue balance is related to extended hardware and software maintenance contracts. Payment terms and conditions vary by contract type, although payment is typically due within 30 to 90 days of contract inception. In instances where the timing of revenue recognition differs from the timing of invoicing, we have determined our contracts generally do not include a significant financing component. The primary purpose of our invoicing terms is to provide customers with simplified and predictable ways of purchasing our products and services, not to receive financing from our customers, such as invoicing at the beginning of a subscription term with a portion of the revenue recognized ratably over the contract period, or to provide customers with financing, such as multi-year on-premises licenses that are invoiced annually with revenue recognized upfront. Changes in deferred revenue, current and non-current, during the nine months ended September 30, 2021 were as follows: (In thousands) Amount Balance as of December 31, 2020 $ 168,486 Deferral of revenue billed in current period, net of recognition 104,092 Recognition of revenue deferred in prior periods (115,999) Foreign currency translation impact (3,539) Balance as of September 30, 2021 (unaudited) $ 153,040 For the nine months ended September 30, 2021, revenue recognized from performance obligations satisfied in prior periods (for example, due to changes in transaction price) was not material. Amounts recognized as revenue in excess of amounts billed are recorded as unbilled receivables. Unbilled receivables which are anticipated to be invoiced in the next twelve months are included in "Other current assets" on the consolidated balance sheet. Based on the nature of our contracts with customers, we do not typically recognize unbilled receivables related to revenues recognized in excess of amounts billed. For the nine months ended September 30, 2021, the amounts recorded that were related to unbilled receivables were not material. Unsatisfied Performance Obligations Revenue expected to be recognized in any future period related to remaining performance obligations, excluding revenue pertaining to contracts that have an original expected duration of one year or less and contracts where revenue is recognized as invoiced, was approximately $61 million as of September 30, 2021. Since we typically invoice customers at contract inception, this amount is included in our current and non-current deferred revenue balances. As of September 30, 2021, we expect to recognize approximately 14% of the revenue related to these unsatisfied performance obligations during the remainder of 2021, 45% during 2022, and 41% thereafter.

Investments

Investments	9 Months Ended
	Sep. 30, 2021
Cash, Cash Equivalents, and Short-term Investments [Abstract]
Investments	Investments The following tables summarize unrealized gains and losses related to our short-term investments designated as available-for-sale debt securities: As of September 30, 2021 (In thousands) (Unaudited) Gross Gross Adjusted Cost Unrealized Gain Unrealized Loss Fair Value Corporate bonds $ — $ — $ — $ — Total short-term investments $ — $ — $ — $ — (In thousands) As of December 31, 2020 Gross Gross Adjusted Cost Unrealized Gain Unrealized Loss Fair Value Corporate bonds $ 59,761 $ 163 $ (1) $ 59,923 Total short-term investments $ 59,761 $ 163 $ (1) $ 59,923 The following tables summarize the contractual maturities of our short-term investments designated as available-for-sale debt securities: As of September 30, 2021 (In thousands) (Unaudited) Due in less than 1 year Adjusted Cost Fair Value Corporate bonds $ — $ — Total available-for-sale debt securities $ — $ — Equity-Method Investments

Fair value measurements

Fair value measurements	9 Months Ended
	Sep. 30, 2021
Fair Value Disclosures [Abstract]
Fair value measurements	Fair value measurements We define fair value to be the price that would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants at the measurement date. When determining the fair value measurements for assets and liabilities required or permitted to be recorded at fair value, we consider the principal or most advantageous market that market participants may use when pricing the asset or liability. We follow a fair value hierarchy that prioritizes the inputs to valuation techniques used to measure fair value. Fair value measurement is determined based on the lowest level input that is significant to the fair value measurement. The three values of the fair value hierarchy are the following: Level 1 – Quoted prices in active markets for identical assets or liabilities Level 2 – Inputs other than quoted prices included within Level 1 that are observable for the asset or liability, either directly or indirectly Level 3 – Inputs that are not based on observable market data Assets and liabilities measured at fair value on a recurring basis are summarized below: Fair Value Measurements at Reporting Date Using (In thousands) (Unaudited) Description September 30, 2021 Level 1 Level 2 Level 3 Assets Cash and cash equivalents: Money market funds $ 113,553 $ 113,553 $ — $ — Other assets Derivatives 10,453 — 10,453 — Total Assets $ 124,006 $ 113,553 $ 10,453 $ — Liabilities Derivatives $ (7,528) $ — $ (7,528) $ — Total Liabilities $ (7,528) $ — $ (7,528) $ — (In thousands) Fair Value Measurements at Reporting Date Using Description December 31, 2020 Level 1 Level 2 Level 3 Assets Cash and cash equivalents: Money market funds $ 145,466 $ 145,466 $ — $ — Short-term investments available for sale: Corporate bonds 59,923 — 59,923 — Other assets Derivatives 6,124 — 6,124 — Total Assets $ 211,513 $ 145,466 $ 66,047 $ — Liabilities Derivatives $ (19,359) $ — $ (19,359) $ — Total Liabilities $ (19,359) $ — $ (19,359) $ — We value our available-for-sale short-term investments based on pricing from third party pricing vendors, who may use quoted prices in active markets for identical assets (Level 1 inputs) or inputs other than quoted prices that are observable either directly or indirectly (Level 2 inputs) in determining fair value. We classify all of our fixed income available-for-sale securities as having Level 2 inputs. The valuation techniques used to measure the fair value of our financial instruments having Level 2 inputs were derived from non-binding market consensus prices that are corroborated by observable market data, quoted market prices for similar instruments, or pricing models, such as discounted cash flow techniques. We believe all of these sources reflect the credit risk associated with each of our available-for-sale short-term investments. Short-term investments available-for-sale consists of debt securities issued by states of the U.S. and political subdivisions of the U.S., corporate debt securities and debt securities issued by U.S. government organizations and agencies. All of our short-term investments available-for-sale have contractual maturities of less than 60 months as of December 31, 2020. Derivatives include foreign currency forward contracts. Our foreign currency forward contracts are valued using an income approach (Level 2) based on the spot rate less the contract rate multiplied by the notional amount. We consider counterparty credit risk in the valuation of our derivatives. However, counterparty credit risk did not impact the valuation of our derivatives during the nine months ended September 30, 2021. There were no transfers in or out of Level 1 or Level 2 during the nine months ended September 30, 2021. We did not have any items that were measured at fair value on a nonrecurring basis at September 30, 2021 and December 31, 2020. The carrying value of net accounts receivable, accounts payable, and long-term debt contained in the consolidated balance sheets approximates fair value.

Derivative instruments and hedg

Derivative instruments and hedging activities	9 Months Ended
	Sep. 30, 2021
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Derivative instruments and hedging activities	Derivative instruments and hedging activities We recognize all of our derivative instruments as either assets or liabilities in our statement of financial position at fair value. The accounting for changes in the fair value (i.e., gains or losses) of a derivative instrument depends on whether it has been designated and qualifies as part of a hedging relationship and further, on the type of hedging relationship. For those derivative instruments that are designated and qualify as hedging instruments, we designate the hedging instrument, based upon the exposure being hedged, as a fair value hedge, cash flow hedge, or a hedge of a net investment in a foreign operation. We have direct operations in approximately 40 countries. Sales outside of the Americas accounted for approximately 59% and 59% of our net sales during the three months ended September 30, 2021 and 2020, respectively, and approximately 61% and 59% during the nine months ended September 30, 2021 and 2020, respectively. Our activities expose us to a variety of market risks, including the effects of changes in foreign currency exchange rates. These financial risks are monitored and managed by us as an integral part of our overall risk management program. We maintain a foreign currency risk management strategy that uses derivative instruments (foreign currency forward contracts) to help protect our earnings and cash flows from fluctuations caused by the volatility in currency exchange rates. Movements in foreign currency exchange rates pose a risk to our operations and competitive position, in that exchange rate changes may affect our profitability and cash flow, and the business or pricing strategies of our non-U.S. based competitors. The vast majority of our foreign sales are denominated in the customers’ local currency. We use foreign currency forward contracts as hedges of forecasted sales that are denominated in foreign currencies and as hedges of foreign currency denominated financial assets or liabilities. These contracts are entered into to help protect against the risk that the eventual dollar-net-cash inflows resulting from such sales or firm commitments will be adversely affected by changes in exchange rates. We also use foreign currency forward contracts as hedges of forecasted expenses that are denominated in foreign currencies. These contracts are entered into to help protect against the risk that the eventual dollar-net-cash outflows resulting from foreign currency operating and cost of sales expenses will be adversely affected by changes in exchange rates. We designate foreign currency forward contracts as cash flow hedges of forecasted net sales or forecasted expenses. In addition, we hedge our foreign currency denominated balance sheet exposures using foreign currency forward contracts that are not designated as hedging instruments. None of our derivative instruments contain a credit-risk-related contingent feature. Cash flow hedges To help protect against the reduction in value caused by a fluctuation in foreign currency exchange rates of forecasted foreign currency cash flows resulting from international sales over the next one For derivative instruments that are designated and qualify as a cash flow hedge, the gain or loss on the derivative is reported as a component of accumulated other comprehensive income ("OCI") and reclassified into earnings in the same line item (net sales, operating expenses, or cost of sales) associated with the forecasted transaction and in the same period or periods during which the hedged transaction affects earnings. Hedge effectiveness of foreign currency forwards designated as cash flow hedges is measured by comparing the hedging instrument’s cumulative change in fair value from inception to maturity to the forecasted transaction’s terminal value. We held forward contracts designated as cash flow hedges with the following notional amounts: (In thousands) US Dollar Equivalent As of September 30, 2021 As of December 31, (Unaudited) 2020 British pound $ 31,445 $ 25,133 Chinese yuan 96,205 45,553 Euro 176,759 219,115 Hungarian forint 64,928 82,429 Japanese yen 53,798 73,399 Korean won 24,092 22,301 Malaysian ringgit 34,536 36,249 Total forward contracts notional amount $ 481,763 $ 504,179 The contracts in the foregoing table had contractual maturities of 27 months or less at September 30, 2021 and 36 months or less at December 31, 2020. At September 30, 2021, we expect to reclassify $3.7 million of gains on derivative instruments from accumulated OCI to net sales during the next twelve months when the hedged international sales occur, $1.0 million of losses on derivative instruments from accumulated OCI to cost of sales during the next twelve months when the hedged cost of sales are incurred and $0.7 million of losses on derivative instruments from accumulated OCI to operating expenses during the next twelve months when the hedged operating expenses occur. Expected amounts are based on derivative valuations at September 30, 2021. Actual results may vary materially as a result of changes in the corresponding exchange rates subsequent to this date. Other Derivatives Other derivatives not designated as hedging instruments consist primarily of foreign currency forward contracts that we use to hedge our foreign denominated monetary assets and liabilities to help protect against the change in value caused by a fluctuation in foreign currency exchange rates. We typically attempt to hedge up to 90% of our outstanding foreign denominated net receivables or net payables and typically limit the duration of these foreign currency forward contracts to approximately 90 days or less. The gain or loss on the derivatives as well as the offsetting gain or loss on the hedge item attributable to the hedged risk is recognized in current earnings under the line item “Other expense.” As of September 30, 2021 and December 31, 2020, we held foreign currency forward contracts that were not designated as hedging instruments with a notional amount of $102 million and $89 million, respectively. The following tables present the fair value of derivative instruments on our Consolidated Balance Sheets at September 30, 2021 and December 31, 2020, respectively. Asset Derivatives September 30, 2021 December 31, 2020 (In thousands) (Unaudited) Balance Sheet Location Fair Value Fair Value Derivatives designated as hedging instruments Foreign exchange contracts - ST forwards Prepaid expenses and other current assets $ 6,118 $ 1,564 Foreign exchange contracts - LT forwards Other long-term assets 3,915 3,117 Total derivatives designated as hedging instruments $ 10,033 $ 4,681 Derivatives not designated as hedging instruments Foreign exchange contracts - ST forwards Prepaid expenses and other current assets $ 420 $ 1,443 Total derivatives not designated as hedging instruments $ 420 $ 1,443 Total derivatives $ 10,453 $ 6,124 Liability Derivatives September 30, 2021 December 31, 2020 (In thousands) (Unaudited) Balance Sheet Location Fair Value Fair Value Derivatives designated as hedging instruments Foreign exchange contracts - ST forwards Other current liabilities $ (4,166) $ (12,549) Foreign exchange contracts - LT forwards Other long-term liabilities (1,470) (6,328) Total derivatives designated as hedging instruments $ (5,636) $ (18,877) Derivatives not designated as hedging instruments Foreign exchange contracts - ST forwards Other current liabilities $ (1,892) $ (482) Total derivatives not designated as hedging instruments $ (1,892) $ (482) Total derivatives $ (7,528) $ (19,359) The following tables present the effect of derivative instruments on our Consolidated Statements of Income for the three months ended September 30, 2021 and 2020, respectively: September 30, 2021 (In thousands) (Unaudited) Derivatives in Cash Flow Hedging Relationship Gain or (Loss) Recognized in OCI on Derivative Location of Gain or (Loss) Reclassified from Accumulated OCI into Income Gain or (Loss) Reclassified from Accumulated OCI into Income Foreign exchange contracts - forwards $ 7,400 Net sales $ (815) Foreign exchange contracts - forwards (1,869) Cost of sales (73) Foreign exchange contracts - forwards (1,288) Operating expenses (88) Total $ 4,243 $ (976) September 30, 2020 (In thousands) (Unaudited) Derivatives in Cash Flow Hedging Relationship Gain or (Loss) Recognized in OCI on Derivative Location of Gain or (Loss) Reclassified from Accumulated OCI into Income Gain or (Loss) Reclassified from Accumulated OCI into Income Foreign exchange contracts - forwards $ (12,524) Net sales $ 334 Foreign exchange contracts - forwards 1,849 Cost of sales (448) Foreign exchange contracts - forwards 1,145 Operating expenses (266) Total $ (9,530) $ (380) (In thousands) Derivatives not Designated as Hedging Instruments Location of Gain (Loss) Recognized in Income Amount of Gain (Loss) Recognized in Income Amount of Gain (Loss) Recognized in Income September 30, 2021 September 30, 2020 (Unaudited) (Unaudited) Foreign exchange contracts - forwards Other expense $ (1,679) (267) Total $ (1,679) $ (267) The following tables present the effect of derivative instruments on our Consolidated Statements of Income for the nine months ended September 30, 2021 and 2020, respectively: September 30, 2021 (In thousands) (Unaudited) Derivatives in Cash Flow Hedging Relationship Gain or (Loss) Recognized in OCI on Derivative Location of Gain or (Loss) Reclassified from Accumulated OCI into Income Gain or (Loss) Reclassified from Accumulated OCI into Income Foreign exchange contracts - forwards $ 23,098 Net sales $ (5,249) Foreign exchange contracts - forwards (2,675) Cost of sales (73) Foreign exchange contracts - forwards (1,819) Operating expenses (70) Total $ 18,604 $ (5,392) September 30, 2020 (In thousands) (Unaudited) Derivatives in Cash Flow Hedging Relationship Gain or (Loss) Recognized in OCI on Derivative Location of Gain or (Loss) Reclassified from Accumulated OCI into Income Gain or (Loss) Reclassified from Accumulated OCI into Income Foreign exchange contracts - forwards $ (6,800) Net sales $ 5,594 Foreign exchange contracts - forwards (1,898) Cost of sales (1,817) Foreign exchange contracts - forwards (1,430) Operating expenses (1,348) Total $ (10,128) $ 2,429 (In thousands) Derivatives not Designated as Hedging Instruments Location of Gain (Loss) Recognized in Income Amount of Gain (Loss) Recognized in Income Amount of Gain (Loss) Recognized in Income September 30, 2021 September 30, 2020 (Unaudited) (Unaudited) Foreign exchange contracts - forwards Other expense $ (3,942) $ (163) Total $ (3,942) $ (163)

Inventories, net

Inventories, net	9 Months Ended
	Sep. 30, 2021
Inventory Disclosure [Abstract]
Inventories, net	Inventories, net Inventories, net consist of the following: September 30, 2021 December 31, (In thousands) (Unaudited) 2020 Raw materials $ 131,725 $ 99,942 Work-in-process 11,458 11,307 Finished goods 93,550 82,763 Total $ 236,733 $ 194,012

Intangible assets, net and good

Intangible assets, net and goodwill	9 Months Ended
	Sep. 30, 2021
Goodwill and Intangible Assets Disclosure [Abstract]
Intangible assets, net and goodwill	Intangible assets, net and goodwill Intangible assets at September 30, 2021 and December 31, 2020 are as follows: September 30, 2021 (In thousands) (Unaudited) December 31, 2020 Gross Carrying Amount Accumulated Amortization Net Carrying Amount Gross Carrying Amount Accumulated Amortization Net Carrying Amount Capitalized software development costs $ 82,099 $ (68,074) $ 14,025 $ 115,251 $ (83,706) $ 31,545 Acquired technology 98,900 (19,017) 79,883 105,486 (17,913) 87,573 Customer relationships 39,747 (15,274) 24,473 40,273 (10,026) 30,247 Patents 35,923 (28,737) 7,186 35,803 (25,578) 10,225 Other 26,885 (15,514) 11,371 27,440 (14,311) 13,129 Total $ 283,554 $ (146,616) $ 136,938 $ 324,253 $ (151,534) $ 172,719 Software development costs capitalized for the three months ended September 30, 2021 and 2020 were $0.6 million and $(0.2) million, respectively, and related amortization expense was $5.6 million and $6.9 million, respectively. For the nine months ended September 30, 2021 and 2020, capitalized software development costs were $1.4 million and $3.1 million, respectively, and related amortization expense was $18.9 million and $21.6 million, respectively. Capitalized software development costs for the three months ended September 30, 2021 and 2020 included costs related to stock-based compensation of less than $0.1 million and $0.1 million, respectively. For the nine months ended September 30, 2021 and 2020, capitalized software development costs included costs related to stock-based compensation of $0.2 million and $0.3 million, respectively. The related amounts in the table above are net of fully amortized assets. Amortization of capitalized software development costs is computed on an individual product basis for those products available for market and is recognized based on the product’s estimated economic life, which generally range from three five ten Goodwill The carrying amount of goodwill as of September 30, 2021, was as follows: (In thousands) Amount Balance as of December 31, 2020 $ 467,547 Acquisitions 16,893 Measurement period adjustments 1,973 Foreign currency translation impact (5,924) Balance as of September 30, 2021 (unaudited) $ 480,489 The excess purchase price over the fair value of assets acquired is recorded as goodwill. As businesses are acquired, we assign assets acquired (including goodwill) and liabilities assumed to either our existing reporting unit or a newly identified reporting unit as of the date of the acquisition. In the event a disposal group meets the definition of a business, goodwill is allocated to the disposal group based on the relative fair value of the disposal group to the related reporting unit. As we have one operating segment comprised of components with similar economic characteristics, we allocate goodwill to one reporting unit for goodwill impairment testing. Goodwill is tested for impairment on an annual basis, and between annual tests if indicators of potential impairment exist, using a fair-value-based approach based on the market capitalization of the reporting unit. Our annual impairment test is performed in the fourth quarter of each year.

Leases

Leases	9 Months Ended
	Sep. 30, 2021
Leases [Abstract]
Leases	Leases We have operating leases for corporate offices, automobiles, and certain equipment. Our leases have remaining terms of 1 year to 93 years, some of which may include options to extend the leases for up to 9 years, and some of which may include options to terminate the leases within 1 year. Leases with an initial term of 12 months or less are not recorded on the balance sheet. We recognize lease expense for these leases on a straight-line basis over the lease term. Amounts related to finance lease activities and income from leasing activities were not material for the periods presented. The components of operating lease expense were as follows (unaudited): Three Months Ended Nine Months Ended (In thousands) September 30, 2021 September 30, 2020 September 30, 2021 September 30, 2020 Operating Lease Cost (1) $ 5,174 $ 4,869 $ 15,712 $ 15,941 (1) Includes variable and short-term lease costs Maturities of lease liabilities as of September 30, 2021 were as follows (unaudited): (In thousands) Years ending December 31, Operating Leases 2021 (Excluding the nine months ended September 30, 2021) $ 4,419 2022 12,815 2023 8,638 2024 7,445 2025 4,949 Thereafter 7,067 Total future minimum lease payments 45,333 Less imputed interest (3,767) Total lease liabilities $ 41,566 As of September 30, 2021, we have additional operating leases that have not commenced during the nine months ended September 30, 2021, which were not material.

Income taxes

Income taxes	9 Months Ended
	Sep. 30, 2021
Income Tax Disclosure [Abstract]
Income taxes	Income taxes We account for income taxes under the asset and liability method. Deferred tax assets and liabilities are recognized for the expected tax consequences of temporary differences between the tax bases of assets and liabilities and their reported amounts. Valuation allowances are established when necessary to reduce deferred tax assets to amounts which are more likely than not to be realized. We had a valuation allowance of $94 million and $93 million at September 30, 2021 and December 31, 2020, respectively. A majority of the valuation allowance is related to the deferred tax assets of National Instruments Hungary Kft. We account for uncertainty in income taxes recognized in our financial statements using prescribed recognition thresholds and measurement attributes for financial statement disclosure of tax positions taken or expected to be taken on our tax returns. We had $10.9 million and $10.5 million of gross unrecognized tax benefits at September 30, 2021 and December 31, 2020, respectively, all of which would affect our effective income tax rate if recognized. We recorded a gross increase in unrecognized tax benefits of $0.2 million for the three months ended September 30, 2021, as a result of the tax positions taken during prior periods. As of September 30, 2021, it is reasonably possible that we will recognize gross tax benefits in the amount of $1.4 million in the next twelve months due to the closing of open tax years. The nature of the uncertainty is related to deductions taken on returns that have not been examined by the applicable tax authority. Our continuing policy is to recognize interest and penalties related to income tax matters in income tax expense. During the three months ended September 30, 2021, we recognized interest expense related to uncertain tax positions of approximately $40,000. As of September 30, 2021, we had approximately $0.5 million accrued for interest related to uncertain tax positions. The tax years 2014 through 2021 remain open to examination by the major taxing jurisdictions to which we are subject. Our provision for income taxes reflected an effective tax rate of 16% and (11)% for the three months ended September 30, 2021 and 2020, respectively, and 16% and 24% for the nine months ended September 30, 2021 and 2020, respectively. For the three months ended September 30, 2021, our effective tax rate was lower than the U.S. federal statutory rate of 21% primarily as a result of an enhanced deduction for certain research and development expenses, the U.S. research and development tax credit, foreign taxes lower than the statutory rate and the deduction for foreign-derived intangible income, offset by the U.S. tax on global intangible low-taxed income, state income taxes net of federal benefit, nondeductible officer compensation and excess tax expense from share-based compensation. For the nine months ended September 30, 2021, our effective tax rate was lower than the U.S. federal statutory rate of 21% primarily as a result of an enhanced deduction for certain research and development expenses, the U.S research and development tax credit and the deduction for foreign-derived intangible income, offset by the U.S. tax on global intangible low-taxed income, state income taxes net of federal benefit and nondeductible officer compensation. For the three months ended September 30, 2020, our effective tax rate was lower than the U.S. federal statutory rate of 21% primarily as a result of foreign taxes lower than the statutory rate, the U.S. research and development tax credit, an enhanced deduction for certain research and development expenses and the deduction for foreign-derived intangible income, offset by state income taxes net of federal benefit, nondeductible officer compensation and nondeductible acquisition costs. For the nine months ended September 30, 2020, our effective tax rate was higher than the U.S. federal statutory rate of 21% primarily as a result of state income taxes net of federal benefit, nondeductible officer compensation, foreign taxes greater than the statutory rate, nondeductible acquisition costs and the gain on the sale of our AWR business, offset by the U.S. research and development tax credit, an enhanced deduction for certain research and development expenses, and the deduction for foreign-derived intangible income. Our earnings from our operations in Hungary are subject to a statutory tax rate of 9%. In addition, our research and development activities in Hungary benefit from a tax law in Hungary that provides for an enhanced deduction for qualified research and development expenses. The tax position of our Hungarian operations resulted in income tax benefits of $1.9 million and $2.2 million for the three and nine months ended September 30, 2021, respectively, and income tax expense of $0.1 million and $0.3 million for the three and nine months ended September 30, 2020, respectively. Earnings from our operations in Malaysia are free of tax under a tax holiday effective January 1, 2013. This tax holiday expires in 2037. If we fail to satisfy the conditions of the tax holiday, this tax benefit may be terminated early. The income tax benefits of the tax holiday for the three and nine months ended September 30, 2021 were approximately $0.6 million and $0.9 million, respectively. The income tax benefits of the tax holiday for the three and nine months ended September 30, 2020 were approximately $0.2 million and $0.4 million, respectively. The impact of the tax holiday on a per share basis for each of the three and nine months ended September 30, 2021 and September 30, 2020 was approximately $0.01 per share. No other taxing jurisdictions had a significant impact on our effective tax rate. We have not entered into any advanced pricing or other agreements with the Internal Revenue Service ("IRS") with regard to any foreign jurisdictions.

Comprehensive income

Comprehensive income	9 Months Ended
	Sep. 30, 2021
Accumulated Other Comprehensive Income (Loss), Net of Tax [Abstract]
Comprehensive income	Comprehensive income Our OCI is comprised of net income, foreign currency translation adjustments, and unrealized gains and losses on forward contracts and securities classified as available-for-sale. The accumulated OCI, net of tax, for the nine months ended September 30, 2021 and 2020, consisted of the following: September 30, 2021 (Unaudited) (In thousands) Currency translation adjustment Investments Derivative instruments Accumulated other comprehensive income/(loss) Balance as of December 31, 2020 $ (10,066) $ (426) (10,334) $ (20,826) Current-period other comprehensive (loss) income (10,585) (162) 13,213 2,466 Reclassified from accumulated OCI into income — — 5,392 5,392 Income (benefit) tax expense — (4) 4,212 4,208 Balance as of September 30, 2021 $ (20,651) $ (584) $ 4,059 $ (17,176) September 30, 2020 (Unaudited) (In thousands) Currency translation adjustment Investments Derivative instruments Accumulated other comprehensive income/(loss) Balance as of December 31, 2019 $ (25,831) $ (85) 4,846 $ (21,070) Current-period other comprehensive income (loss) 6,507 (317) (7,699) (1,509) Reclassified from accumulated OCI into income — — (2,429) (2,429) Income tax benefit — (45) (2,223) (2,268) Balance as of September 30, 2020 $ (19,324) $ (357) $ (3,059) $ (22,740)

Authorized shares of common and

Authorized shares of common and preferred stock and stock-based compensation plans	9 Months Ended
	Sep. 30, 2021
Share-based Payment Arrangement [Abstract]
Authorized shares of common and preferred stock and stock-based compensation plans	Authorized shares of common and preferred stock and stock-based compensation plans Authorized shares of common and preferred stock The total number of shares which we are authorized to issue is 365,000,000 shares, consisting of (i) 5,000,000 shares of preferred stock, par value $0.01 per share, and (ii) 360,000,000 shares of common stock, par value $0.01 per share. Stock-Based Compensation Plan Our stockholders approved our 2005 Incentive Plan (the “2005 Plan”) on May 10, 2005. At the time of approval, 4,050,000 shares of our common stock were reserved for issuance under the 2005 Plan, as well as the number of shares which had been reserved but not issued under our 1994 Incentive Stock Options Plan (the “1994 Plan”) which terminated in May 2005, and any shares that returned to the 1994 Plan as a result of termination of options or repurchase of shares issued under such plan. The 2005 Plan provided for the granting of incentive awards in the form of restricted stock and RSUs to directors, executive officers and employees of the Company and its subsidiaries. Awards vest over a three five Our stockholders approved our 2010 Incentive Plan (the “2010 Plan”) on May 11, 2010. At the time of approval, 3,000,000 shares of our common stock were reserved for issuance under the 2010 Plan, as well as the 3,362,304 shares of common stock that were reserved but not issued under the 1994 Plan and the 2005 Plan as of May 11, 2010, and any shares that are returned to the 1994 Plan and the 2005 Plan as a result of the forfeiture or termination of options or RSUs or repurchase of shares issued under those plans. The 2010 Plan provided for the granting of incentive awards in the form of restricted stock and RSUs to employees, directors and consultants of the Company and employees and consultants of any parent or subsidiary of the Company. Awards vest over a three five Our stockholders approved our 2015 Equity Incentive Plan (the “2015 Plan”) on May 12, 2015. At the time of approval, 3,000,000 shares of our common stock were reserved for issuance under the 2015 Plan, as well as the 2,518,416 shares of common stock that were reserved but not issued under the 2010 Plan as of May 12, 2015, and any shares that were returned to the 1994 Plan, 2005 Plan, and the 2010 Plan as a result of the forfeiture or termination of options or RSUs or repurchase of shares issued under those plans. The 2015 Plan provides for the granting of incentive awards in the form of restricted stock and RSUs to employees, directors and consultants of the Company and employees and consultants of any parent or subsidiary of the Company and such awards may be subject to performance-based vesting conditions. Awards generally vest over a three four five five Our stockholders approved our 2020 Equity Incentive Plan (the “2020 Plan”) on May 5, 2020. At the time of approval, 4,500,000 shares of our common stock were reserved for issuance under the 2020 Plan, as well as the 567,142 shares of common stock that were reserved but not issued under the 2015 Plan as of May 5, 2020, and any shares that were returned to the 1994 Plan, 2005 Plan, 2010 Plan, and 2015 Plan as a result of the forfeiture or termination of options or RSUs or repurchase of shares issued under those plans. The 2020 Plan provides for the granting of incentive awards in the form of restricted stock and RSUs to employees, directors and consultants of the Company and employees and consultants of any parent or subsidiary of the Company. Awards generally vest over a one two three Performance-based stock units During the nine months ended September 30, 2021 and 2020, we granted 130,006 and 144,647 performance-based restricted stock units (“PRSUs”), respectively, to executive officers pursuant to the 2020 Plan and 2015 Plan. The PRSUs may be earned based on our total shareholder return ("TSR") compared to the TSR of the Russell 2000 Index (the “Index”) over a three-year performance period. For the PRSUs granted during the nine months ended September 30, 2021, the three-year performance period commenced on January 1, 2021 and will end on December 31, 2023, and for the PRSUs granted during the nine months ended September 30, 2020, the three year performance commenced on January 1, 2020 and will end on December 31, 2022, using the average daily closing price over a 30-day lookback in each case. The number of awards earned could range from zero to two times the target number of shares granted. The fair values of PRSUs are estimated using a Monte Carlo simulation. The determination of fair value of the PRSUs is based on our stock price and a number of assumptions including the expected volatility, expected dividend yield and the risk-free interest rate. The expected volatility at the date of grant was based on the historical volatilities of our stock and the companies included in the Index over the performance period. The Monte Carlo model is based on random projections of stock-price paths and must be repeated numerous times to achieve a probabilistic assessment. The key assumptions used in valuing these market-based awards are as follows: Nine Months Ended (unaudited) September 30, 2021 September 30, 2020 Number of simulations 100,000 100,000 Expected volatility 40.60% 27.41% Expected life in years 2.95 years 2.92 years Risk-free interest rate 0.21% 1.38% Dividend yield 2.66% 2.32% The weighted average grant date fair value of the market-based awards, as determined by the Monte Carlo valuation model, was $66.97 per share and $61.00 per share in 2021 and 2020, respectively. Employee stock purchase plan Our employee stock purchase plan (“ESPP”) permits substantially all domestic employees and employees of designated subsidiaries to acquire our common stock at a purchase price of 85% of the lower of the market price at the beginning or the end of the purchase period. The plan has quarterly purchase periods generally beginning on February 1, May 1, August 1 and November 1 of each year. Employees may designate up to 15% of their compensation for the purchase of common stock under the ESPP. On May 14, 2019, our stockholders approved an additional 3,000,000 shares for issuance under our ESPP. At September 30, 2021, we had 2,257,649 shares of common stock reserved for future issuance under the ESPP. We issued 801,543 shares under this plan in the nine months ended September 30, 2021 and the weighted average purchase price was $31.74 per share. During the nine months ended September 30, 2021, we did not make any changes in accounting principles or methods of estimates with respect to our ESPP. Authorized Preferred Stock and Preferred Stock Purchase Rights Plan We have 5,000,000 authorized shares of preferred stock. There were no shares of preferred stock issued and outstanding at September 30, 2021. Stock repurchases and retirements On April 21, 2010, our Board of Directors authorized a program to repurchase of shares of our common stock from time to time, depending on market conditions and other factors (the "Program"). The Board of Directors has amended the Program several times over the years to increase the number of shares that may be purchased under the Program. Most recently, on October 23, 2019, our Board amended the Program to increase the number of shares that may be repurchased by 3,000,000 shares. At September 30, 2021, there were 1,010,877 shares remaining available for repurchase under the Program. During the three and nine months ended September 30, 2021, we repurchased 599,066 shares of our common stock at a weighted average price per share of $41.73. During the three months ended September 30, 2020, we repurchased 446,502 shares of our common stock at a weighted average price per share of $34.86 and during the nine months ended September 30, 2020, we repurchased 1,114,701 shares of our common stock at a weighted average price per share of $35.21. The Program does not have an expiration date.

Segment and geographic informat

Segment and geographic information	9 Months Ended
	Sep. 30, 2021
Segment Reporting [Abstract]
Segment and geographic information	Segment and geographic information We operate as one operating segment. Operating segments are defined as components of an enterprise for which separate financial information is evaluated regularly by the chief operating decision maker, who is our chief executive officer, in deciding how to allocate resources and in assessing performance. Our chief operating decision maker evaluates our financial information and resources and assesses the performance of these resources on a consolidated basis. Since we operate as one operating segment, all required financial segment information can be found in the condensed consolidated financial statements and the notes thereto. We sell our products in three geographic regions which consist of Americas, EMEA and APAC. Our sales to these regions share similar economic characteristics including the nature of products and services we sell, the type and class of customers, and the methods used to distribute our products and services. Revenue from the sale of our products, which are similar in nature, and software maintenance is reflected as total net sales in our Consolidated Statements of Income. (See Note 2 - Revenue of Notes to Consolidated Financial Statements for total net sales by the major geographic areas in which we operate). The following table presents summarized information for net sales by country. Revenues from external customers are generally attributed to countries based upon the customer's location. Net sales attributable to each individual foreign country outside the U.S. and China were not material. (in millions) United States China (1) Rest of the World Total Net sales: Three months ended September 30, 2021 $ 141 $ 59 $ 167 $ 367 Three months ended September 30, 2020 $ 121 $ 52 $ 135 $ 308 Nine months ended September 30, 2021 $ 388 $ 172 $ 489 $ 1,049 Nine months ended September 30, 2020 $ 355 $ 139 $ 425 $ 919 (1): Includes Mainland China and the Hong Kong Special Administrative Region The following table presents summarized information for long-lived assets by country. Long-lived assets attributable to each individual country outside the U.S., Hungary and Malaysia were not material. Long-lived assets consist of property, plant, and equipment, operating lease right-of-use assets and other long-term assets excluding intangible assets. (in millions) United States Hungary Malaysia Rest of the World Total Long-lived Assets: September 30, 2021 $ 127 $ 51 $ 75 $ 56 $ 309 December 31, 2020 $ 127 $ 52 $ 75 $ 68 $ 322

Debt

Debt	9 Months Ended
	Sep. 30, 2021
Debt Disclosure [Abstract]
Debt	Debt On June 18, 2021, we entered into a Second Amended and Restated Credit Agreement (the "Credit Agreement") with Wells Fargo Bank, National Association, as the administrative agent, swingline lender and issuing lender (the “Administrative Agent”), Wells Fargo Securities, LLC, as sole lead arranger and bookrunner, and the lenders party thereto. The Credit Agreement amended and restated and refinanced our prior Amended and Restated Credit Agreement, dated as of June 12, 2020, by and among us, the lenders from time-to-time party thereto and Administrative Agent, as amended on October 30, 2020. The Credit Agreement provides for a secured revolving loan facility in an aggregate principal amount of up to $500 million at any time outstanding, with a sublimit of $25 million for the issuance of letters of credit. Subject to the terms and conditions of the Credit Agreement, including obtaining commitments from existing lenders or new lenders, we may request term loans or additional revolving commitments. Pursuant the Credit Agreement, the revolving line of credit terminates, and all revolving loans under the Credit Agreement will be due and payable, on June 18, 2026. The revolving loans accrue interest, at our option, at a base rate equal to the highest of (a) the prime rate, (b) the federal funds rate plus 0.50%, and (c) a LIBOR loan interest rate of LIBOR for an interest period of one month plus 1.00%, plus a margin of 0.25% to 0.75%, or LIBOR plus a margin of 1.25% to 1.75%, with the margin being determined based upon our consolidated total net leverage ratio. The Credit Agreement contains financial covenants requiring us to maintain a maximum total net leverage ratio of less than or equal to 3.50 to 1.00, which increases to 4.00 to 1.00 for a specified period following material acquisitions, and a minimum interest coverage ratio of greater than or equal to 3.00 to 1.00, in each case determined in accordance with the Credit Agreement. The Credit Agreement provides for a commitment fee of 0.150% to 0.250% per annum, determined based upon our consolidated total net leverage ratio, on the average daily unused amount of the revolving committed amount, payable quarterly in arrears. Under the circumstances described in the Credit Agreement, certain of our wholly-owned domestic subsidiaries (the "Subsidiary Guarantors") are required to enter into a guaranty agreement ("Guaranty") in favor of the Administrative Agent guarantying the obligations of the Company under the Credit Agreement, among other things. There is no Subsidiary Guarantor, and no Guaranty has been executed in connection with the Credit Agreement at this time. In connection with the Credit Agreement, we, our Subsidiary Guarantors from time-to-time party thereto and the Administrative Agent have entered (or will enter in the case of the future Subsidiary Guarantors) into an Amended and Restated Collateral Agreement pursuant to which we and each of our Subsidiary Guarantor from time-to-time have granted (or will grant) a lien on substantially all of their assets to secure their obligations under the Credit Agreement and the Guaranty. The Credit Agreement contains customary affirmative and negative covenants. The affirmative covenants include, among other things, delivery of financial statements, compliance certificates and notices, payment of taxes and other obligations, maintenance of existence, maintenance of properties and insurance, maintenance of books and records, and compliance with applicable laws and regulations. The negative covenants include, among other things, limitations on indebtedness, liens, mergers, consolidations, acquisitions and sales of assets, investments, changes in the nature of the business, affiliate transactions and certain restricted payments. The Credit Agreement contains customary events of default including, among other things, payment defaults, breaches of covenants or representations and warranties, cross-defaults with certain other indebtedness, bankruptcy and insolvency events, judgment defaults and change in control events, subject to grace periods in certain instances. Upon an event of default, the Administrative Agent and the lenders may declare all or a portion of the outstanding obligations payable by us to be immediately due and payable and exercise other rights and remedies provided for under the Credit Agreement. Under certain circumstances, a default interest rate will apply on all obligations during the existence of an event of default under the Credit Agreement at a per annum rate of interest equal to 2.00% above the otherwise applicable interest rate. Proceeds of revolving loans of the Credit Agreement may be used for working capital and other general corporate purposes. We may prepay the loans under the Credit Agreement in whole or in part at any time without premium or penalty. The following table presents the amounts outstanding related to our borrowing arrangements discussed above as of September 30, 2021 (unaudited) and December 31, 2020, respectively (in thousands): September 30, December 31, (in thousands) 2021 2020 Secured 2020 Term loan (effective interest rate of 1.7%) $ — $ 98,750 2021 Revolving line of credit (effective interest rate of 1.3%) 100,000 — Total Debt 100,000 98,750 Less: Unamortized debt issuance costs — (1,714) Less: Current portion of total debt — (5,000) Total Debt, non-current $ 100,000 $ 92,036 As of September 30, 2021, debt issuance costs of approximately $2.6 million attributable to the revolving line of credit are presented within "Other long-term assets" in our Consolidated Balance Sheet. These amounts are amortized to interest expense ratably over the life of the revolving line of credit.

Commitments and contingencies

Commitments and contingencies	9 Months Ended
	Sep. 30, 2021
Commitments and Contingencies Disclosure [Abstract]
Commitments and contingencies	Commitments and contingencies We offer a one-year limited warranty on most hardware products which is included in the terms of sale of such products. We also offer optional extended warranties on our hardware products for which the related revenue is recognized ratably over the warranty period. Provision is made for estimated future warranty costs at the time of the sale for the estimated costs that may be incurred under the standard warranty. Our estimate is based on historical experience and product sales during the period. The warranty reserve for the nine months ended September 30, 2021 and 2020 was as follows: Nine Months Ended September 30, (In thousands) (Unaudited) 2021 2020 Balance at the beginning of the period $ 2,872 $ 2,561 Accruals for warranties issued during the period 2,037 1,824 Accruals related to pre-existing warranties (636) 405 Settlements made (in cash or in kind) during the period (1,291) (2,088) Balance at the end of the period $ 2,982 $ 2,702 As of September 30, 2021, we had certain off-balance sheet commitments that require the future purchase of goods or services ("unconditional purchase obligations"). Our unconditional purchase obligations primarily consist of payments to various suppliers for customized inventory and inventory components. As of September 30, 2021, our total future payments under noncancellable unconditional purchase obligations having a remaining term in excess of one year were approximately $3.2 million.

Restructuring

Restructuring	9 Months Ended
	Sep. 30, 2021
Restructuring and Related Activities [Abstract]
Restructuring	Restructuring On October 29, 2020, we announced a workforce reduction plan (the “Plan”) intended to accelerate our growth strategy and further optimize our operations and cost structure. The majority of charges related to this Plan were recognized during the three months ended December 31, 2020. We implemented a majority of the actions under this Plan as of September 30, 2021. A summary of the charges in our consolidated statement of operations resulting from our restructuring activities is shown below: Three Months Ended September 30, Nine Months Ended September 30, (In thousands) (Unaudited) (Unaudited) 2021 2020 2021 2020 Cost of sales $ (7) $ (13) $ (50) $ 7 Research and development 65 38 444 4,716 Sales and marketing (223) 512 3,924 8,055 General and administrative 54 121 2,159 683 Total restructuring and other related costs $ (111) $ 658 $ 6,477 $ 13,461 A summary of balance sheet activity related to our restructuring activity is shown below: (in thousands) Restructuring Liability Balance as of December 31, 2020 $ 28,993 Income statement expense 6,477 Cash payments (30,389) Balance as of September 30, 2021 $ 5,081 The restructuring liability of $5.1 million at September 30, 2021 related primarily to severance payments associated with the restructuring activity is recorded in the “accrued compensation” line item of our consolidated balance sheet.

Litigation

Litigation	9 Months Ended
	Sep. 30, 2021
Commitments and Contingencies Disclosure [Abstract]
Litigation	Litigation    We are not currently a party to any material litigation. However, in the ordinary course of our business, we have in the past, are currently and may likely become involved in various legal proceedings, claims, and regulatory, tax or government inquiries and investigations, and could incur uninsured liability in any one or more of them. We also periodically receive notifications from various third parties related to alleged infringement of patents or intellectual property rights, commercial disputes or other matters. No assurances can be given with respect to the extent or outcome of any investigation, litigation or dispute.

Acquisitions

Acquisitions	9 Months Ended
	Sep. 30, 2021
Business Combination and Asset Acquisition [Abstract]
Acquisitions	Acquisitions Acquisition of OptimalPlus On July 2, 2020, we completed the acquisition of OptimalPlus Ltd. (“OptimalPlus”), a global leader in data analytics software for the semiconductor, automotive and electronics industries that is based in Israel. As a result of acquiring 100% of the outstanding share capital of OptimalPlus, OptimalPlus became our wholly-owned subsidiary. This transaction was accounted for as a business combination using the acquisition method of accounting. All of the acquired assets and liabilities of OptimalPlus have been recorded at their respective fair values as of the acquisition date. Transaction costs have been expensed as incurred. The acquisition was funded primarily by cash on hand in addition to $70 million drawn under our prior term loan facility on June 30, 2020. See Note 13 – Debt of Notes to Consolidated Financial Statements for further information on our outstanding borrowings. During the twelve months ended December 31, 2020, we expensed $7 million of transaction costs in connection with the acquisition of OptimalPlus, which are included in selling, general and administrative expenses. At the acquisition date, total consideration transferred was approximately $353 million, inclusive of $18 million in cash acquired. Additionally, unvested in-the-money share options of certain OptimalPlus employees were exchanged into the right to receive deferred cash consideration in accordance with the terms of the share purchase agreement. Approximately $12 million of deferred cash consideration was allocated to post-combination expense and is not included in the total consideration transferred. The deferred cash consideration is subject to the original vesting schedule of the corresponding unvested options that were replaced and the amounts will be recognized as compensation expense over the remaining service period. The excess of the purchase price over the net assets acquired was recorded as goodwill. Goodwill generated from the acquisition is primarily attributable to expected growth in the scope of and market opportunities for our software-defined automated test and measurement platform. As a result of the structure of the transaction, the balance of goodwill is deductible in the U.S. over 15 years for income tax purposes. Fair value of net assets acquired and liabilities assumed The information below represents the purchase price allocation of OptimalPlus: (in thousands) July 2, 2020 Consideration Transferred $ 352,642 Cash 17,661 Intangible assets 129,000 Goodwill 205,038 Contract assets 15,454 Deferred revenue (7,341) Accounts receivable 4,927 Other assets and liabilities (4,516) Deferred tax liabilities (7,581) Net assets acquired $ 352,642 We finalized the purchase price allocation for our acquisition of OptimalPlus during the second quarter of 2021. Since the preliminary estimates reported in the third quarter of 2020, we updated certain amounts related to current and deferred income taxes, reflected in the final purchase price allocation, as summarized in the fair values of assets acquired and liabilities assumed in the table above. Measurement period adjustments were recognized in the reporting period in which the adjustments were determined and calculated as if the accounting had been completed at the acquisition date. Acquired intangible assets will be amortized over their estimated useful lives on a straight-line basis. The following table summarizes the purchase price allocation, and the average remaining useful lives, for identifiable intangible assets acquired: (dollars in thousands) Estimated Fair Value Estimated Useful Lives (in years) Customer relationships $ 30,100 5 Developed technology 82,400 6 In-process research and development (IPR&D) 10,400 6 Other intangibles 6,100 3-5 Total $ 129,000 Developed technology and IPR&D relate to software platforms for data analytics in the semiconductor, automotive, and electronic industries that combine machine-learning with a global data infrastructure to provide real-time product analytics and extract insights from data across the entire supply chain. We valued the developed technology and IPR&D using the multi-period excess earnings method under the income approach. This method reflects the present value of the projected cash flows that are expected to be generated by the technology less charges representing the contribution of other assets to those cash flows. The economic useful life was determined based on the technology cycle related to each technology, as well as the cash flows over the forecast period. IPR&D was initially capitalized at fair value as an intangible asset with an indefinite life and assessed for impairment thereafter. When a project underlying reported IPR&D is completed, the corresponding amount of IPR&D is amortized over the asset’s estimated useful life. Customer relationships represent the fair value of future projected revenue that will be derived from sales of products to existing customers. Customer relationships were valued using the with-and-without-method under the income approach. In the with-and-without method, the fair value was measured by the difference between the present values of the cash flows with and without the existing customers in place over the period of time necessary to reacquire the customers. The economic useful life was determined by evaluating many factors, including the useful life of other intangible assets, the length of time remaining on the acquired contracts and the historical customer turnover rates. Unaudited Pro Forma Information The results of OptimalPlus have been included in our consolidated statements of income for the period subsequent to the acquisition date. The following unaudited pro forma financial information presents combined results of operations for the periods presented, as if the OptimalPlus acquisition had occurred on January 1, 2019, with adjustments to give effect to pro forma events that are directly attributable to the acquisition. These pro forma adjustments include additional amortization expense for the identifiable intangible assets, a reduction in revenue related to deferred revenue purchase accounting adjustments, an increase in interest expense related to the term loan entered into in connection with the acquisition, and adjustments to compensation expense for the replacement of unvested share options discussed above, net of tax effects. For the pro forma presentation, given the assumed acquisition date of January 1, 2019, transaction and integration costs that were incurred at or subsequent to the actual acquisition date have been included in the calculation of pro forma net income for the three and nine months ended September 30, 2020, whereas transaction and integration costs that were incurred prior to the acquisition date have been excluded from the calculation of pro forma net income. The unaudited pro forma results are presented for informational purposes only and are not necessarily indicative of what actual results of operations would have been if the acquisition had occurred as the beginning of the period presented, nor are they indicative of future results of operations. The unaudited pro forma results do not include the impact of synergies, nor any potential impacts on current or future market conditions which could alter the unaudited pro forma results. Three Months Ended September 30, Nine Months Ended September 30, 2020 (in thousands) Net sales $ 309,142 $ 929,381 Net income $ 4,907 $ 123,676 Other Acquisitions During the second quarter of 2021, we also completed the acquisition of a software company that specializes in signal processing and hi-fi simulation software for validation of autonomous vehicles and advanced driver assistance systems (ADAS), for approximately $20 million in total cash consideration, subject to certain post-closing adjustments. This transaction was accounted for as a business combination using the acquisition method of accounting. All of the acquired assets and liabilities of the software company have been recorded at their respective fair values as of the acquisition date. We recognized approximately $17 million of goodwill and $4 million of other intangible assets as part of our preliminary purchase price allocation. Transaction costs have been expensed as incurred and were not material to the periods presented. The preliminary purchase price allocation related to the acquisition was not finalized as of September 30, 2021, and is based upon a preliminary valuation which is subject to change as we obtain additional information with respect to certain intangible assets and income taxes. Pro-forma results of operations have not been presented because the effects of the acquired operations were not material.

Subsequent events

Subsequent events	9 Months Ended
	Sep. 30, 2021
Subsequent Events [Abstract]
Subsequent events	Subsequent events Dividends On October 19, 2021, our Board of Directors declared a quarterly cash dividend of $0.27 per common share, payable on November 29, 2021, to stockholders of record on November 8, 2021. Acquisitions On October 19, 2021, we completed the acquisition of NH Research (NHR), a manufacturer of test and measurement solutions for high power applications including electric vehicles and batteries. This transaction is being accounted for as a business combination. All of the acquired assets and liabilities of the acquired business will be recorded at their respective fair values as of the acquisition date. Transaction costs will be expensed as incurred. At the acquisition date, total consideration transferred was approximately $200 million, inclusive of $3 million in cash acquired. The acquisition was funded by $200 million drawn under our existing credit facility in October 2021. See Note 13 - Debt of Notes to Consolidated Financial Statements for further information on our outstanding borrowings. We have excluded certain disclosures required under ASC Topic 805. Disclosure of certain information has been deemed impracticable primarily due to the short period of time we have had to obtain the necessary information from the acquired company, which is not a public company. This short timeframe prohibits us from fully applying various valuation methodologies and preparing the information for this Quarterly Report on Form 10-Q for the third quarter of 2021. Such information, as required under Topic 805, will be included in our Annual Report on Form 10-K for the year ended 2021, and finalized within the one-year measurement period. Restructuring On October 26, 2021, we initiated a restructuring plan (the “2021 Plan”) that will result in the site closure of our facilities in Aachen, Germany. This targeted restructuring effort is intended to accelerate our growth strategy and further optimize our operations and cost structure. In connection with the 2021 Plan, we currently estimate that we will incur pre-tax charges of approximately $8 million to $9 million, consisting primarily of severance payments and other employee-related costs. We expect that the majority of these charges will be recognized during the fourth quarter of 2021.

Basis of presentation (Policies

Basis of presentation (Policies)	9 Months Ended
	Sep. 30, 2021
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Basis of presentation	Basis of presentation The accompanying unaudited consolidated financial statements should be read in conjunction with the consolidated financial statements and notes thereto for the fiscal year ended December 31, 2020, included in our Annual Report on Form 10-K filed with the Securities and Exchange Commission ("SEC") on February 23, 2021 (the "Form 10-K"). In our opinion, the accompanying consolidated financial statements reflect all adjustments (consisting only of normal recurring items) considered necessary to present fairly our financial position at September 30, 2021 and December 31, 2020, the results of our operations and comprehensive income for three and nine months ended September 30, 2021 and 2020, our cash flows for the nine months ended September 30, 2021 and 2020 and our statement of stockholders' equity for the three and nine months ended September 30, 2021 and 2020. Our operating results for the three and nine months ended September 30, 2021 are not necessarily indicative of the results that may be expected for the year ending December 31, 2021. These financial statements have been prepared in accordance with accounting principles generally accepted in the United States.
Reclassifications	Reclassifications Certain reclassifications have been made to prior period amounts to conform to the current period presentation.
Recently Adopted Accounting Pronouncements and Recently Issued Accounting Pronouncements	Recently Adopted Accounting Pronouncements Clarification of Equity Method Transition In January 2020, the Financial Accounting Standards Board ("FASB") issued Accounting Standards Update ("ASU") 2020-01, “Investments-Equity Securities (Topic 321), Investments-Equity Method and Joint Ventures (Topic 323), and Derivatives and Hedging (Topic 815): Clarifying the Interactions between Topic 321, Topic 323, and Topic 815,” which clarifies the interaction of the accounting for equity investments under Topic 321 and investments accounted for under the equity method of accounting in Topic 323 and the accounting for certain forward contracts and purchased options accounted for under Topic 815. The standard is effective for public companies for fiscal years, and interim periods within those fiscal years, beginning after December 15, 2020. We adopted ASU 2020-01 on January 1, 2021, and the new standard did not have a material impact on our consolidated financial statements and related disclosures. Recently Issued Accounting Pronouncements Although there are several other accounting pronouncements recently issued by the FASB, we do not expect the adoption of any of these accounting pronouncements had or will have a material impact on our consolidated financial statements. Summary of Significant Accounting Policies There were no changes in our significant accounting policies during the three and nine months ended September 30, 2021 compared to the significant accounting policies described in our Form 10-K.
Earnings Per Share	Earnings Per ShareBasic earnings per share (“EPS”) is computed by dividing net income by the weighted average number of common shares outstanding during each period. Diluted EPS is computed by dividing net income by the weighted average number of common shares and common share equivalents outstanding (if dilutive) during each period. The number of common share equivalents, which includes restricted stock units ("RSUs"), is computed using the treasury stock method.

Basis of presentation (Tables)

Basis of presentation (Tables)	9 Months Ended
	Sep. 30, 2021
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Schedule of Derecognition of Assets and Liabilities	The divestiture of AWR resulted in the derecognition of the following assets and liabilities: (In thousands) Cash $ 1,027 Accounts receivable, net 7,233 Prepaid and other current assets 283 Goodwill 7,221 Other non-current assets 556 Total Assets 16,320 Deferred revenue 15,296 Other current liabilities 940 Cumulative translation adjustment (660) Total liabilities and stockholders' equity 15,576 Total assets divested, net (including cash) $ 744
Other Expense, Net	Other expense, net consisted of the following amounts: Three Months Ended September 30, Nine Months Ended September 30, (In thousands) (Unaudited) (Unaudited) 2021 2020 2021 2020 Interest income $ 56 $ 414 $ 330 $ 3,724 Interest expense (657) (973) (2,584) (1,115) Gain (loss) from equity-method investments 278 (627) (5,082) (2,559) Net foreign exchange loss (1,226) (676) (2,681) (2,019) Other (271) (139) 166 (615) Other expense, net $ (1,820) $ (2,001) $ (9,851) $ (2,584)
Schedule of Reconciliation of the Denominators used to Calculate Basic and Diluted EPS	The reconciliation of the denominators used to calculate basic EPS and diluted EPS for the three and nine months ended September 30, 2021 and 2020 are as follows (in thousands): Three Months Ended September 30, Nine Months Ended September 30, (Unaudited) (Unaudited) 2021 2020 2021 2020 Weighted average shares outstanding-basic 133,031 131,419 132,657 131,017 Plus: Common share equivalents RSUs 655 — 1,172 654 Weighted average shares outstanding-diluted 133,686 131,419 133,829 131,671
Schedule of Other Current Liabilities	Other current liabilities on our consolidated balance sheet includes the following amounts: As of September 30, 2021 As of December 31, (In thousands) (unaudited) 2020 Income taxes payable - current $ 2,590 $ 13,720 Hedge payable - current 6,058 13,031 Other 16,514 15,827 Total $ 25,162 $ 42,578

Revenue (Tables)

Revenue (Tables)	9 Months Ended
	Sep. 30, 2021
Revenue from Contract with Customer [Abstract]
Schedule of Disaggregation of Revenue	Total net sales based on the disaggregation criteria described above are as follows: Three Months Ended September 30, (In thousands) (Unaudited) 2021 2020 Net sales: Point-in-Time (1) Over Time Total Point-in-Time (1) Over Time Total Americas $ 125,069 $ 23,835 $ 148,904 $ 107,808 $ 19,241 $ 127,049 EMEA 72,430 22,433 94,863 57,988 20,551 78,539 APAC 112,931 10,464 123,395 92,050 10,486 102,536 Total net sales (1) $ 310,430 $ 56,732 $ 367,162 $ 257,846 $ 50,278 $ 308,124 (1) Net sales contains hedging gains and losses, which do not represent revenues recognized from customers. Nine Months Ended September 30, (In thousands) (Unaudited) 2021 2020 Net sales: Point-in-Time (1) Over Time Total Point-in-Time (1) Over Time Total Americas $ 341,870 $ 68,436 $ 410,306 $ 316,220 $ 57,554 $ 373,774 EMEA 204,786 64,769 269,555 181,330 58,594 239,924 APAC 337,455 31,724 369,179 274,341 30,795 305,136 Total net sales (1) $ 884,111 $ 164,929 $ 1,049,040 $ 771,891 $ 146,943 $ 918,834 (1) Net sales contains hedging gains and losses, which do not represent revenues recognized from customers.
Schedule of Changes in Unearned Revenue	Changes in deferred revenue, current and non-current, during the nine months ended September 30, 2021 were as follows: (In thousands) Amount Balance as of December 31, 2020 $ 168,486 Deferral of revenue billed in current period, net of recognition 104,092 Recognition of revenue deferred in prior periods (115,999) Foreign currency translation impact (3,539) Balance as of September 30, 2021 (unaudited) $ 153,040

Investments (Tables)

Investments (Tables)	9 Months Ended
	Sep. 30, 2021
Cash, Cash Equivalents, and Short-term Investments [Abstract]
Schedule of Unrealized Gains and Losses on Short-term Investments	The following tables summarize unrealized gains and losses related to our short-term investments designated as available-for-sale debt securities: As of September 30, 2021 (In thousands) (Unaudited) Gross Gross Adjusted Cost Unrealized Gain Unrealized Loss Fair Value Corporate bonds $ — $ — $ — $ — Total short-term investments $ — $ — $ — $ — (In thousands) As of December 31, 2020 Gross Gross Adjusted Cost Unrealized Gain Unrealized Loss Fair Value Corporate bonds $ 59,761 $ 163 $ (1) $ 59,923 Total short-term investments $ 59,761 $ 163 $ (1) $ 59,923
Schedule of Contractual Maturities of Short-term Investments	The following tables summarize the contractual maturities of our short-term investments designated as available-for-sale debt securities: As of September 30, 2021 (In thousands) (Unaudited) Due in less than 1 year Adjusted Cost Fair Value Corporate bonds $ — $ — Total available-for-sale debt securities $ — $ —

Fair value measurements (Tables

Fair value measurements (Tables)	9 Months Ended
	Sep. 30, 2021
Fair Value Disclosures [Abstract]
Schedule of Fair Value, Assets and Liabilities Measured on Recurring Basis	Assets and liabilities measured at fair value on a recurring basis are summarized below: Fair Value Measurements at Reporting Date Using (In thousands) (Unaudited) Description September 30, 2021 Level 1 Level 2 Level 3 Assets Cash and cash equivalents: Money market funds $ 113,553 $ 113,553 $ — $ — Other assets Derivatives 10,453 — 10,453 — Total Assets $ 124,006 $ 113,553 $ 10,453 $ — Liabilities Derivatives $ (7,528) $ — $ (7,528) $ — Total Liabilities $ (7,528) $ — $ (7,528) $ — (In thousands) Fair Value Measurements at Reporting Date Using Description December 31, 2020 Level 1 Level 2 Level 3 Assets Cash and cash equivalents: Money market funds $ 145,466 $ 145,466 $ — $ — Short-term investments available for sale: Corporate bonds 59,923 — 59,923 — Other assets Derivatives 6,124 — 6,124 — Total Assets $ 211,513 $ 145,466 $ 66,047 $ — Liabilities Derivatives $ (19,359) $ — $ (19,359) $ — Total Liabilities $ (19,359) $ — $ (19,359) $ —

Derivative instruments and he_2

Derivative instruments and hedging activities (Tables)	9 Months Ended
	Sep. 30, 2021
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Schedule of Forward Contracts Notional Amount	We held forward contracts designated as cash flow hedges with the following notional amounts: (In thousands) US Dollar Equivalent As of September 30, 2021 As of December 31, (Unaudited) 2020 British pound $ 31,445 $ 25,133 Chinese yuan 96,205 45,553 Euro 176,759 219,115 Hungarian forint 64,928 82,429 Japanese yen 53,798 73,399 Korean won 24,092 22,301 Malaysian ringgit 34,536 36,249 Total forward contracts notional amount $ 481,763 $ 504,179
Summary of Fair Value of Derivative Instruments	The following tables present the fair value of derivative instruments on our Consolidated Balance Sheets at September 30, 2021 and December 31, 2020, respectively. Asset Derivatives September 30, 2021 December 31, 2020 (In thousands) (Unaudited) Balance Sheet Location Fair Value Fair Value Derivatives designated as hedging instruments Foreign exchange contracts - ST forwards Prepaid expenses and other current assets $ 6,118 $ 1,564 Foreign exchange contracts - LT forwards Other long-term assets 3,915 3,117 Total derivatives designated as hedging instruments $ 10,033 $ 4,681 Derivatives not designated as hedging instruments Foreign exchange contracts - ST forwards Prepaid expenses and other current assets $ 420 $ 1,443 Total derivatives not designated as hedging instruments $ 420 $ 1,443 Total derivatives $ 10,453 $ 6,124 Liability Derivatives September 30, 2021 December 31, 2020 (In thousands) (Unaudited) Balance Sheet Location Fair Value Fair Value Derivatives designated as hedging instruments Foreign exchange contracts - ST forwards Other current liabilities $ (4,166) $ (12,549) Foreign exchange contracts - LT forwards Other long-term liabilities (1,470) (6,328) Total derivatives designated as hedging instruments $ (5,636) $ (18,877) Derivatives not designated as hedging instruments Foreign exchange contracts - ST forwards Other current liabilities $ (1,892) $ (482) Total derivatives not designated as hedging instruments $ (1,892) $ (482) Total derivatives $ (7,528) $ (19,359)
Schedule of Effect of Derivative Instruments	The following tables present the effect of derivative instruments on our Consolidated Statements of Income for the three months ended September 30, 2021 and 2020, respectively: September 30, 2021 (In thousands) (Unaudited) Derivatives in Cash Flow Hedging Relationship Gain or (Loss) Recognized in OCI on Derivative Location of Gain or (Loss) Reclassified from Accumulated OCI into Income Gain or (Loss) Reclassified from Accumulated OCI into Income Foreign exchange contracts - forwards $ 7,400 Net sales $ (815) Foreign exchange contracts - forwards (1,869) Cost of sales (73) Foreign exchange contracts - forwards (1,288) Operating expenses (88) Total $ 4,243 $ (976) September 30, 2020 (In thousands) (Unaudited) Derivatives in Cash Flow Hedging Relationship Gain or (Loss) Recognized in OCI on Derivative Location of Gain or (Loss) Reclassified from Accumulated OCI into Income Gain or (Loss) Reclassified from Accumulated OCI into Income Foreign exchange contracts - forwards $ (12,524) Net sales $ 334 Foreign exchange contracts - forwards 1,849 Cost of sales (448) Foreign exchange contracts - forwards 1,145 Operating expenses (266) Total $ (9,530) $ (380) (In thousands) Derivatives not Designated as Hedging Instruments Location of Gain (Loss) Recognized in Income Amount of Gain (Loss) Recognized in Income Amount of Gain (Loss) Recognized in Income September 30, 2021 September 30, 2020 (Unaudited) (Unaudited) Foreign exchange contracts - forwards Other expense $ (1,679) (267) Total $ (1,679) $ (267) The following tables present the effect of derivative instruments on our Consolidated Statements of Income for the nine months ended September 30, 2021 and 2020, respectively: September 30, 2021 (In thousands) (Unaudited) Derivatives in Cash Flow Hedging Relationship Gain or (Loss) Recognized in OCI on Derivative Location of Gain or (Loss) Reclassified from Accumulated OCI into Income Gain or (Loss) Reclassified from Accumulated OCI into Income Foreign exchange contracts - forwards $ 23,098 Net sales $ (5,249) Foreign exchange contracts - forwards (2,675) Cost of sales (73) Foreign exchange contracts - forwards (1,819) Operating expenses (70) Total $ 18,604 $ (5,392) September 30, 2020 (In thousands) (Unaudited) Derivatives in Cash Flow Hedging Relationship Gain or (Loss) Recognized in OCI on Derivative Location of Gain or (Loss) Reclassified from Accumulated OCI into Income Gain or (Loss) Reclassified from Accumulated OCI into Income Foreign exchange contracts - forwards $ (6,800) Net sales $ 5,594 Foreign exchange contracts - forwards (1,898) Cost of sales (1,817) Foreign exchange contracts - forwards (1,430) Operating expenses (1,348) Total $ (10,128) $ 2,429 (In thousands) Derivatives not Designated as Hedging Instruments Location of Gain (Loss) Recognized in Income Amount of Gain (Loss) Recognized in Income Amount of Gain (Loss) Recognized in Income September 30, 2021 September 30, 2020 (Unaudited) (Unaudited) Foreign exchange contracts - forwards Other expense $ (3,942) $ (163) Total $ (3,942) $ (163)

Inventories, net (Tables)

Inventories, net (Tables)	9 Months Ended
	Sep. 30, 2021
Inventory Disclosure [Abstract]
Schedule of Inventories, Net	Inventories, net consist of the following: September 30, 2021 December 31, (In thousands) (Unaudited) 2020 Raw materials $ 131,725 $ 99,942 Work-in-process 11,458 11,307 Finished goods 93,550 82,763 Total $ 236,733 $ 194,012

Intangible assets, net and go_2

Intangible assets, net and goodwill  (Tables)	9 Months Ended
	Sep. 30, 2021
Goodwill and Intangible Assets Disclosure [Abstract]
Schedule of Intangible Assets	Intangible assets at September 30, 2021 and December 31, 2020 are as follows: September 30, 2021 (In thousands) (Unaudited) December 31, 2020 Gross Carrying Amount Accumulated Amortization Net Carrying Amount Gross Carrying Amount Accumulated Amortization Net Carrying Amount Capitalized software development costs $ 82,099 $ (68,074) $ 14,025 $ 115,251 $ (83,706) $ 31,545 Acquired technology 98,900 (19,017) 79,883 105,486 (17,913) 87,573 Customer relationships 39,747 (15,274) 24,473 40,273 (10,026) 30,247 Patents 35,923 (28,737) 7,186 35,803 (25,578) 10,225 Other 26,885 (15,514) 11,371 27,440 (14,311) 13,129 Total $ 283,554 $ (146,616) $ 136,938 $ 324,253 $ (151,534) $ 172,719
Schedule of Goodwill	The carrying amount of goodwill as of September 30, 2021, was as follows: (In thousands) Amount Balance as of December 31, 2020 $ 467,547 Acquisitions 16,893 Measurement period adjustments 1,973 Foreign currency translation impact (5,924) Balance as of September 30, 2021 (unaudited) $ 480,489

Leases (Tables)

Leases (Tables)	9 Months Ended
	Sep. 30, 2021
Leases [Abstract]
Components of Lease Expense	The components of operating lease expense were as follows (unaudited): Three Months Ended Nine Months Ended (In thousands) September 30, 2021 September 30, 2020 September 30, 2021 September 30, 2020 Operating Lease Cost (1) $ 5,174 $ 4,869 $ 15,712 $ 15,941 (1) Includes variable and short-term lease costs
Schedule of Maturities of Lease Liabilities	Maturities of lease liabilities as of September 30, 2021 were as follows (unaudited): (In thousands) Years ending December 31, Operating Leases 2021 (Excluding the nine months ended September 30, 2021) $ 4,419 2022 12,815 2023 8,638 2024 7,445 2025 4,949 Thereafter 7,067 Total future minimum lease payments 45,333 Less imputed interest (3,767) Total lease liabilities $ 41,566

Comprehensive income (Tables)

Comprehensive income (Tables)	9 Months Ended
	Sep. 30, 2021
Accumulated Other Comprehensive Income (Loss), Net of Tax [Abstract]
Summary of Accumulated OCI, Net of Tax	The accumulated OCI, net of tax, for the nine months ended September 30, 2021 and 2020, consisted of the following: September 30, 2021 (Unaudited) (In thousands) Currency translation adjustment Investments Derivative instruments Accumulated other comprehensive income/(loss) Balance as of December 31, 2020 $ (10,066) $ (426) (10,334) $ (20,826) Current-period other comprehensive (loss) income (10,585) (162) 13,213 2,466 Reclassified from accumulated OCI into income — — 5,392 5,392 Income (benefit) tax expense — (4) 4,212 4,208 Balance as of September 30, 2021 $ (20,651) $ (584) $ 4,059 $ (17,176) September 30, 2020 (Unaudited) (In thousands) Currency translation adjustment Investments Derivative instruments Accumulated other comprehensive income/(loss) Balance as of December 31, 2019 $ (25,831) $ (85) 4,846 $ (21,070) Current-period other comprehensive income (loss) 6,507 (317) (7,699) (1,509) Reclassified from accumulated OCI into income — — (2,429) (2,429) Income tax benefit — (45) (2,223) (2,268) Balance as of September 30, 2020 $ (19,324) $ (357) $ (3,059) $ (22,740)

Authorized shares of common a_2

Authorized shares of common and preferred stock and stock-based compensation plans (Tables)	9 Months Ended
	Sep. 30, 2021
Share-based Payment Arrangement [Abstract]
Schedule of Key Assumptions to Value Market-based Awards	The key assumptions used in valuing these market-based awards are as follows: Nine Months Ended (unaudited) September 30, 2021 September 30, 2020 Number of simulations 100,000 100,000 Expected volatility 40.60% 27.41% Expected life in years 2.95 years 2.92 years Risk-free interest rate 0.21% 1.38% Dividend yield 2.66% 2.32%

Segment and geographic inform_2

Segment and geographic information (Tables)	9 Months Ended
	Sep. 30, 2021
Segment Reporting [Abstract]
Schedule of Net Sales by Country	The following table presents summarized information for net sales by country. Revenues from external customers are generally attributed to countries based upon the customer's location. Net sales attributable to each individual foreign country outside the U.S. and China were not material. (in millions) United States China (1) Rest of the World Total Net sales: Three months ended September 30, 2021 $ 141 $ 59 $ 167 $ 367 Three months ended September 30, 2020 $ 121 $ 52 $ 135 $ 308 Nine months ended September 30, 2021 $ 388 $ 172 $ 489 $ 1,049 Nine months ended September 30, 2020 $ 355 $ 139 $ 425 $ 919 (1): Includes Mainland China and the Hong Kong Special Administrative Region The following table presents summarized information for long-lived assets by country. Long-lived assets attributable to each individual country outside the U.S., Hungary and Malaysia were not material. Long-lived assets consist of property, plant, and equipment, operating lease right-of-use assets and other long-term assets excluding intangible assets. (in millions) United States Hungary Malaysia Rest of the World Total Long-lived Assets: September 30, 2021 $ 127 $ 51 $ 75 $ 56 $ 309 December 31, 2020 $ 127 $ 52 $ 75 $ 68 $ 322

Debt (Tables)

Debt (Tables)	9 Months Ended
	Sep. 30, 2021
Debt Disclosure [Abstract]
Schedule of Amounts Outstanding related to Borrowing Arrangements	The following table presents the amounts outstanding related to our borrowing arrangements discussed above as of September 30, 2021 (unaudited) and December 31, 2020, respectively (in thousands): September 30, December 31, (in thousands) 2021 2020 Secured 2020 Term loan (effective interest rate of 1.7%) $ — $ 98,750 2021 Revolving line of credit (effective interest rate of 1.3%) 100,000 — Total Debt 100,000 98,750 Less: Unamortized debt issuance costs — (1,714) Less: Current portion of total debt — (5,000) Total Debt, non-current $ 100,000 $ 92,036

Commitments and contingencies (

Commitments and contingencies (Tables)	9 Months Ended
	Sep. 30, 2021
Commitments and Contingencies Disclosure [Abstract]
Schedule of Product Warranty Liability	The warranty reserve for the nine months ended September 30, 2021 and 2020 was as follows: Nine Months Ended September 30, (In thousands) (Unaudited) 2021 2020 Balance at the beginning of the period $ 2,872 $ 2,561 Accruals for warranties issued during the period 2,037 1,824 Accruals related to pre-existing warranties (636) 405 Settlements made (in cash or in kind) during the period (1,291) (2,088) Balance at the end of the period $ 2,982 $ 2,702

Restructuring (Tables)

Restructuring (Tables)	9 Months Ended
	Sep. 30, 2021
Restructuring and Related Activities [Abstract]
Summary of Charges Resulting From Restructuring Activities	A summary of the charges in our consolidated statement of operations resulting from our restructuring activities is shown below: Three Months Ended September 30, Nine Months Ended September 30, (In thousands) (Unaudited) (Unaudited) 2021 2020 2021 2020 Cost of sales $ (7) $ (13) $ (50) $ 7 Research and development 65 38 444 4,716 Sales and marketing (223) 512 3,924 8,055 General and administrative 54 121 2,159 683 Total restructuring and other related costs $ (111) $ 658 $ 6,477 $ 13,461
Schedule of Restructuring Reserve by Type of Cost	A summary of balance sheet activity related to our restructuring activity is shown below: (in thousands) Restructuring Liability Balance as of December 31, 2020 $ 28,993 Income statement expense 6,477 Cash payments (30,389) Balance as of September 30, 2021 $ 5,081

Acquisitions (Tables)

Acquisitions (Tables)	9 Months Ended
	Sep. 30, 2021
Business Combination and Asset Acquisition [Abstract]
Schedule of Preliminary Purchase Price Allocation	The information below represents the purchase price allocation of OptimalPlus: (in thousands) July 2, 2020 Consideration Transferred $ 352,642 Cash 17,661 Intangible assets 129,000 Goodwill 205,038 Contract assets 15,454 Deferred revenue (7,341) Accounts receivable 4,927 Other assets and liabilities (4,516) Deferred tax liabilities (7,581) Net assets acquired $ 352,642
Summary of Preliminary Purchase Price Allocation and Useful Lives	The following table summarizes the purchase price allocation, and the average remaining useful lives, for identifiable intangible assets acquired: (dollars in thousands) Estimated Fair Value Estimated Useful Lives (in years) Customer relationships $ 30,100 5 Developed technology 82,400 6 In-process research and development (IPR&D) 10,400 6 Other intangibles 6,100 3-5 Total $ 129,000
Schedule of Pro Forma Information	Three Months Ended September 30, Nine Months Ended September 30, 2020 (in thousands) Net sales $ 309,142 $ 929,381 Net income $ 4,907 $ 123,676

Basis of presentation - Narrati

Basis of presentation - Narrative (Details) - USD ($) $ in Thousands	Jan. 15, 2020	Sep. 30, 2021	Sep. 30, 2020
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Disposal gain on sale of business/assets		$ 0	$ 159,753
AWR Corporation | Divestiture by sale
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Proceeds from sale of business	$ 161,000
Disposal gain on sale of business/assets	160,000
Transaction costs	$ 1,000

Basis of Presentation - Disposa

Basis of Presentation - Disposal Groups, Including Discontinued Operations (Details) - Divestiture by sale - AWR Corporation $ in Thousands	Jan. 15, 2020USD ($)
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Cash	$ 1,027
Accounts receivable, net	7,233
Prepaid and other current assets	283
Goodwill	7,221
Other non-current assets	556
Total Assets	16,320
Deferred revenue	15,296
Other current liabilities	940
Cumulative translation adjustment	(660)
Total liabilities and stockholders' equity	15,576
Total assets divested, net (including cash)	$ 744

Basis of presentation - Other E

Basis of presentation - Other Expense, Net (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Interest income	$ 56	$ 414	$ 330	$ 3,724
Interest expense	(657)	(973)	(2,584)	(1,115)
Gain (loss) from equity-method investments	278	(627)	(5,082)	(2,559)
Net foreign exchange loss	(1,226)	(676)	(2,681)	(2,019)
Other	(271)	(139)	166	(615)
Other expense, net	$ (1,820)	$ (2,001)	$ (9,851)	$ (2,584)

Basis of presentation - Schedul

Basis of presentation - Schedule of Earnings Per Share (Details) - shares	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Weighted average shares outstanding - basic (in shares)	133,031,000	131,419,000	132,657,000	131,017,000
Plus: Common share equivalents
RSUs (in shares)	655,000	0	1,172,000	654,000
Weighted average shares outstanding-diluted (in shares)	133,686,000	131,419,000	133,829,000	131,671,000
RSU
Plus: Common share equivalents
Anti-dilutive securities excluded from the computation of diluted EPS (in shares)	143,000	3,490,700	123,000	276,000

Basis of presentation - Sched_2

Basis of presentation - Schedule of Other Current Liabilities (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Income taxes payable - current	$ 2,590	$ 13,720
Hedge payable - current	6,058	13,031
Other	16,514	15,827
Other current liabilities	$ 25,162	$ 42,578

Revenue - Disaggregation of Rev

Revenue - Disaggregation of Revenue (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Disaggregation of Revenue [Line Items]
Total net sales	$ 367,162	$ 308,124	$ 1,049,040	$ 918,834
Point-in-Time
Disaggregation of Revenue [Line Items]
Total net sales	310,430	257,846	884,111	771,891
Over Time
Disaggregation of Revenue [Line Items]
Total net sales	56,732	50,278	164,929	146,943
Americas
Disaggregation of Revenue [Line Items]
Total net sales	148,904	127,049	410,306	373,774
Americas | Point-in-Time
Disaggregation of Revenue [Line Items]
Total net sales	125,069	107,808	341,870	316,220
Americas | Over Time
Disaggregation of Revenue [Line Items]
Total net sales	23,835	19,241	68,436	57,554
EMEA
Disaggregation of Revenue [Line Items]
Total net sales	94,863	78,539	269,555	239,924
EMEA | Point-in-Time
Disaggregation of Revenue [Line Items]
Total net sales	72,430	57,988	204,786	181,330
EMEA | Over Time
Disaggregation of Revenue [Line Items]
Total net sales	22,433	20,551	64,769	58,594
APAC
Disaggregation of Revenue [Line Items]
Total net sales	123,395	102,536	369,179	305,136
APAC | Point-in-Time
Disaggregation of Revenue [Line Items]
Total net sales	112,931	92,050	337,455	274,341
APAC | Over Time
Disaggregation of Revenue [Line Items]
Total net sales	$ 10,464	$ 10,486	$ 31,724	$ 30,795

Revenue - Narrative (Details)

Revenue - Narrative (Details) $ in Millions	9 Months Ended
	Sep. 30, 2021USD ($)
Revenue from Contract with Customer [Abstract]
Payment terms	Amounts collected in advance of services being provided are accounted for as deferred revenue. Nearly all of our deferred revenue balance is related to extended hardware and software maintenance contracts. Payment terms and conditions vary by contract type, although payment is typically due within 30 to 90 days of contract inception.
Undelivered performance obligation	$ 61
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date: 2021-10-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Remaining performance obligation, percent	14.00%
Performance obligation, term	3 months
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date: 2022-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Remaining performance obligation, percent	45.00%
Performance obligation, term	1 year
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date: 2023-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Remaining performance obligation, percent	41.00%
Performance obligation, term

Revenue - Change in Unearned Re

Revenue - Change in Unearned Revenue (Details) $ in Thousands	9 Months Ended
	Sep. 30, 2021USD ($)
Movement in Deferred Revenue [Roll Forward]
Deferred revenue, beginning balance	$ 168,486
Deferral of revenue billed in current period, net of recognition	104,092
Recognition of revenue deferred in prior periods	(115,999)
Foreign currency translation impact	(3,539)
Deferred revenue, ending balance	$ 153,040

Investments - Unrealized Gains

Investments - Unrealized Gains And Losses Related To Short-Term Investments Designated As Available-For-Sale (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Debt Securities, Available-for-sale [Line Items]
Adjusted Cost	$ 0	$ 59,761
Gross Unrealized Gain	0	163
Gross Unrealized Loss	0	(1)
Fair Value	0	59,923
Corporate bonds
Debt Securities, Available-for-sale [Line Items]
Adjusted Cost	0	59,761
Gross Unrealized Gain	0	163
Gross Unrealized Loss	0	(1)
Fair Value	$ 0	$ 59,923

Investments - Contractual Matur

Investments - Contractual Maturities Of Short-Term Investments Designated As Available-For-Sale (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2021	Sep. 30, 2021	Dec. 31, 2020
Adjusted Cost
Due in less than 1 year		$ 0
Fair Value
Due in less than 1 year		0
Carrying value of equity method investments		33,000	$ 25,000
Impairment loss	$ 3,500
Corporate bonds
Adjusted Cost
Due in less than 1 year		0
Fair Value
Due in less than 1 year		$ 0

Fair value measurements (Detail

Fair value measurements (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Short-term investments available for sale:
Available-for-sale	$ 0	$ 59,923
Other assets
Derivatives	10,453	6,124
Total Assets	124,006	211,513
Derivatives	(7,528)	(19,359)
Total Liabilities	(7,528)	$ (19,359)
Available-for-sale contractual maturity (in months)		60 months
Level 1
Other assets
Derivatives	0	$ 0
Total Assets	113,553	145,466
Derivatives	0	0
Total Liabilities	0	0
Level 2
Other assets
Derivatives	10,453	6,124
Total Assets	10,453	66,047
Derivatives	(7,528)	(19,359)
Total Liabilities	(7,528)	(19,359)
Level 3
Other assets
Derivatives	0	0
Total Assets	0	0
Derivatives	0	0
Total Liabilities	0	0
Money market funds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and cash equivalents	113,553	145,466
Money market funds | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and cash equivalents	113,553	145,466
Money market funds | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and cash equivalents	0	0
Money market funds | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and cash equivalents	$ 0	0
Corporate bonds
Short-term investments available for sale:
Available-for-sale		59,923
Corporate bonds | Level 1
Short-term investments available for sale:
Available-for-sale		0
Corporate bonds | Level 2
Short-term investments available for sale:
Available-for-sale		59,923
Corporate bonds | Level 3
Short-term investments available for sale:
Available-for-sale		$ 0

Derivative instruments and he_3

Derivative instruments and hedging activities - Narrative (Details) $ in Thousands	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2021USD ($)country	Sep. 30, 2020	Sep. 30, 2021USD ($)country	Sep. 30, 2020	Dec. 31, 2020USD ($)
Derivative [Line Items]
Number of countries for which entity has direct operations | country	40		40
Period of protection against the reduction in value caused by a fluctuation, minimum (in number of years)			1 year
Period of protection against the reduction in value caused by a fluctuation, maximum (in number of years)			3 years
Duration of foreign currency forward contracts (or less)			27 months		36 months
Foreign currency forward contracts notional amount	$ 481,763		$ 481,763		$ 504,179
Forward Contracts
Derivative [Line Items]
Duration of time, foreign currency cash flow hedge			40 months
Forward Contracts | Net sales
Derivative [Line Items]
Gains (losses) expected to be reclassified from AOCI to earnings (less than for Operating expenses)			$ 3,700
Forward Contracts | Cost of sales
Derivative [Line Items]
Gains (losses) expected to be reclassified from AOCI to earnings (less than for Operating expenses)			(1,000)
Forward Contracts | Operating expenses
Derivative [Line Items]
Gains (losses) expected to be reclassified from AOCI to earnings (less than for Operating expenses)			$ (700)
Forward Contracts | Maximum
Derivative [Line Items]
Percentage of derivative risk hedged	100.00%		100.00%
Other Derivatives
Derivative [Line Items]
Foreign currency forward contracts notional amount	$ 102,000		$ 102,000		$ 89,000
Other Derivatives | Maximum
Derivative [Line Items]
Percentage of derivative risk hedged	90.00%		90.00%
Duration of foreign currency forward contracts (or less)			90 days
Net sales | Outside of the Americas | Non-Americas
Derivative [Line Items]
Concentration risk	59.00%	59.00%	61.00%	59.00%

Derivative instruments and he_4

Derivative instruments and hedging activities - Summary Of Notional Amounts Of Derivative Instruments (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Derivative [Line Items]
Total forward contracts notional amount	$ 481,763	$ 504,179
British pound
Derivative [Line Items]
Total forward contracts notional amount	31,445	25,133
Chinese yuan
Derivative [Line Items]
Total forward contracts notional amount	96,205	45,553
Euro
Derivative [Line Items]
Total forward contracts notional amount	176,759	219,115
Hungarian forint
Derivative [Line Items]
Total forward contracts notional amount	64,928	82,429
Japanese yen
Derivative [Line Items]
Total forward contracts notional amount	53,798	73,399
Korean won
Derivative [Line Items]
Total forward contracts notional amount	24,092	22,301
Malaysian ringgit
Derivative [Line Items]
Total forward contracts notional amount	$ 34,536	$ 36,249

Derivative instruments and he_5

Derivative instruments and hedging activities - Fair Value Of Derivative Instruments On Consolidated Balance Sheets (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Derivatives, Fair Value [Line Items]
Derivative assets	$ 10,453	$ 6,124
Derivative liability	(7,528)	(19,359)
Derivatives designated as hedging instruments
Derivatives, Fair Value [Line Items]
Derivative assets	10,033	4,681
Derivative liability	(5,636)	(18,877)
Derivatives designated as hedging instruments | Foreign exchange contracts - ST forwards | Prepaid expenses and other current assets
Derivatives, Fair Value [Line Items]
Derivative assets	6,118	1,564
Derivatives designated as hedging instruments | Foreign exchange contracts - ST forwards | Other current liabilities
Derivatives, Fair Value [Line Items]
Derivative liability	(4,166)	(12,549)
Derivatives designated as hedging instruments | Foreign exchange contracts - LT forwards | Other long-term assets
Derivatives, Fair Value [Line Items]
Derivative assets	3,915	3,117
Derivatives designated as hedging instruments | Foreign exchange contracts - LT forwards | Other long-term liabilities
Derivatives, Fair Value [Line Items]
Derivative liability	(1,470)	(6,328)
Derivatives not designated as hedging instruments
Derivatives, Fair Value [Line Items]
Derivative assets	420	1,443
Derivative liability	(1,892)	(482)
Derivatives not designated as hedging instruments | Foreign exchange contracts - ST forwards | Prepaid expenses and other current assets
Derivatives, Fair Value [Line Items]
Derivative assets	420	1,443
Derivatives not designated as hedging instruments | Foreign exchange contracts - ST forwards | Other current liabilities
Derivatives, Fair Value [Line Items]
Derivative liability	$ (1,892)	$ (482)

Derivative instruments and he_6

Derivative instruments and hedging activities - Effect Of Derivative Instruments On Consolidated Statements Of Income (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Derivatives designated as hedging instruments
Derivative Instruments, Gain (Loss) [Line Items]
Gain or (Loss) Recognized in OCI on Derivative	$ 4,243	$ (9,530)	$ 18,604	$ (10,128)
Gain or (Loss) Reclassified from Accumulated OCI into Income	(976)	(380)	(5,392)	2,429
Derivatives designated as hedging instruments | Foreign exchange contracts - forwards | Net sales
Derivative Instruments, Gain (Loss) [Line Items]
Gain or (Loss) Reclassified from Accumulated OCI into Income	(815)	334	(5,249)	5,594
Derivatives designated as hedging instruments | Foreign exchange contracts - forwards | Cost of sales
Derivative Instruments, Gain (Loss) [Line Items]
Gain or (Loss) Reclassified from Accumulated OCI into Income	(73)	(448)	(73)	(1,817)
Derivatives designated as hedging instruments | Foreign exchange contracts - forwards | Operating expenses
Derivative Instruments, Gain (Loss) [Line Items]
Gain or (Loss) Reclassified from Accumulated OCI into Income	(88)	(266)	(70)	(1,348)
Derivatives designated as hedging instruments | Foreign Exchange Forward A
Derivative Instruments, Gain (Loss) [Line Items]
Gain or (Loss) Recognized in OCI on Derivative	7,400	(12,524)	23,098	(6,800)
Derivatives designated as hedging instruments | Foreign Exchange Forward B
Derivative Instruments, Gain (Loss) [Line Items]
Gain or (Loss) Recognized in OCI on Derivative	(1,869)	1,849	(2,675)	(1,898)
Derivatives designated as hedging instruments | Foreign Exchange Forward C
Derivative Instruments, Gain (Loss) [Line Items]
Gain or (Loss) Recognized in OCI on Derivative	(1,288)	1,145	(1,819)	(1,430)
Derivatives not designated as hedging instruments
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain (Loss) Recognized in Income	(1,679)	(267)	(3,942)	(163)
Derivatives not designated as hedging instruments | Foreign exchange contracts - forwards | Other expense
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain (Loss) Recognized in Income	$ (1,679)	$ (267)	$ (3,942)	$ (163)

Inventories, net (Details)

Inventories, net (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Inventory Disclosure [Abstract]
Raw materials	$ 131,725	$ 99,942
Work-in-process	11,458	11,307
Finished goods	93,550	82,763
Total	$ 236,733	$ 194,012

Intangible assets, net and go_3

Intangible assets, net and goodwill - Schedule Of Finite-Lived Intangible Assets (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	$ 283,554	$ 324,253
Accumulated Amortization	(146,616)	(151,534)
Net Carrying Amount	136,938	172,719
Capitalized software development costs
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	82,099	115,251
Accumulated Amortization	(68,074)	(83,706)
Net Carrying Amount	14,025	31,545
Acquired technology
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	98,900	105,486
Accumulated Amortization	(19,017)	(17,913)
Net Carrying Amount	79,883	87,573
Customer relationships
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	39,747	40,273
Accumulated Amortization	(15,274)	(10,026)
Net Carrying Amount	24,473	30,247
Patents
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	35,923	35,803
Accumulated Amortization	(28,737)	(25,578)
Net Carrying Amount	7,186	10,225
Other
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	26,885	27,440
Accumulated Amortization	(15,514)	(14,311)
Net Carrying Amount	$ 11,371	$ 13,129

Intangible assets, net and go_4

Intangible assets, net and goodwill - Narrative (Details)	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2021USD ($)	Sep. 30, 2020USD ($)	Sep. 30, 2021USD ($)segment	Sep. 30, 2020USD ($)	Dec. 31, 2020USD ($)
Finite-Lived Intangible Assets [Line Items]
Amortization of intangible assets	$ 13,400,000	$ 14,200,000	$ 43,300,000	$ 32,900,000
Number of operating segments | segment			1
Goodwill impairment			$ 0		$ 0
Capitalized software development costs
Finite-Lived Intangible Assets [Line Items]
Software development costs capitalized	600,000	(200,000)	1,400,000	3,100,000
Amortization expense of capitalized software development costs	5,600,000	6,900,000	18,900,000	21,600,000
Costs related to stock based compensation (less than for three months ended June 30, 2021)	$ 100,000	$ 100,000	$ 200,000	$ 300,000
Capitalized software development costs | Minimum
Finite-Lived Intangible Assets [Line Items]
Intangible assets amortization period (in years)			3 years
Capitalized software development costs | Maximum
Finite-Lived Intangible Assets [Line Items]
Intangible assets amortization period (in years)			6 years
Acquired technology | Minimum
Finite-Lived Intangible Assets [Line Items]
Intangible assets amortization period (in years)			5 years
Acquired technology | Maximum
Finite-Lived Intangible Assets [Line Items]
Intangible assets amortization period (in years)			10 years
Patents | Minimum
Finite-Lived Intangible Assets [Line Items]
Intangible assets amortization period (in years)			10 years
Patents | Maximum
Finite-Lived Intangible Assets [Line Items]
Intangible assets amortization period (in years)			17 years

Intangible assets, net and go_5

Intangible assets, net and goodwill - Schedule of Goodwill (Details) $ in Thousands	9 Months Ended
	Sep. 30, 2021USD ($)
Goodwill [Roll Forward]
Balance at beginning of period	$ 467,547
Acquisitions	16,893
Measurement period adjustments	1,973
Foreign currency translation impact	(5,924)
Balance at end of period	$ 480,489

Leases - Summary of Components

Leases - Summary of Components of Lease Expense and Other Information (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Lessee, Lease, Description [Line Items]
Option to terminate period			1 year
Operating Lease Cost	$ 5,174	$ 4,869	$ 15,712	$ 15,941
Minimum
Lessee, Lease, Description [Line Items]
Remaining term	1 year		1 year
Maximum
Lessee, Lease, Description [Line Items]
Remaining term	93 years		93 years
Option to extend term	9 years		9 years

Leases - Maturities of Lease Li

Leases - Maturities of Lease Liabilities (Details) $ in Thousands	Sep. 30, 2021USD ($)
Leases [Abstract]
2021 (Excluding the nine months ended September 30, 2021)	$ 4,419
2022	12,815
2023	8,638
2024	7,445
2025	4,949
Thereafter	7,067
Total future minimum lease payments	45,333
Less imputed interest	(3,767)
Total lease liabilities	$ 41,566

Income taxes (Details)

Income taxes (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020
Operating Loss Carryforwards [Line Items]
Valuation allowance	$ 94		$ 94		$ 93
Unrecognized tax benefits	10.9		10.9		$ 10.5
Unrecognized tax benefits, period increase (decrease)	0.2
Reasonable possibility of future tax benefits	1.4		1.4
Interest expense related to uncertain tax positions (less than)	40
Accrued interest related to uncertain tax positions	$ 0.5		$ 0.5
Effective income tax rate	16.00%	(11.00%)	16.00%	24.00%
Hungary
Operating Loss Carryforwards [Line Items]
Hungary statutory tax rate			9.00%
Foreign income tax benefit	$ 1.9	$ 0.1	$ 2.2	$ 0.3
Malaysia
Operating Loss Carryforwards [Line Items]
Income tax benefit of tax holiday, amount	$ 0.6	$ 0.2	$ 0.9	$ 0.4
Income tax benefit of tax holiday (in usd per share)	$ 0.01		$ 0.01

Comprehensive income (Details)

Comprehensive income (Details) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning Balance	$ 1,224,871	$ 1,176,350
Current-period other comprehensive (loss) income	2,466	(1,509)
Reclassified from accumulated OCI into income	5,392	(2,429)
Income (benefit) tax expense	4,208	(2,268)
Ending Balance	1,226,472	1,239,198
Currency translation adjustment
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning Balance	(10,066)	(25,831)
Current-period other comprehensive (loss) income	(10,585)	6,507
Reclassified from accumulated OCI into income	0	0
Income (benefit) tax expense	0	0
Ending Balance	(20,651)	(19,324)
Investments
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning Balance	(426)	(85)
Current-period other comprehensive (loss) income	(162)	(317)
Reclassified from accumulated OCI into income	0	0
Income (benefit) tax expense	(4)	(45)
Ending Balance	(584)	(357)
Derivative instruments
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning Balance	(10,334)	4,846
Current-period other comprehensive (loss) income	13,213	(7,699)
Reclassified from accumulated OCI into income	5,392	(2,429)
Income (benefit) tax expense	4,212	(2,223)
Ending Balance	4,059	(3,059)
Accumulated other comprehensive income/(loss)
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning Balance	(20,826)	(21,070)
Ending Balance	$ (17,176)	$ (22,740)

Authorized shares of common a_3

Authorized shares of common and preferred stock and stock-based compensation plans - Narrative (Details) - $ / shares

Jan. 01, 2021

May 05, 2020

Jan. 01, 2020

May 12, 2015

May 11, 2010

May 10, 2005

Sep. 30, 2021

Sep. 30, 2020

Sep. 30, 2021

Sep. 30, 2020

Dec. 31, 2020

Oct. 23, 2019

May 14, 2019

Share-based Compensation Arrangement by Share-based Payment Award [Line Items]

Common and preferred stock shares authorized (in shares)

365,000,000

365,000,000

Preferred stock, authorized (in shares)

5,000,000

5,000,000

5,000,000

Preferred stock, par value per share (in usd per share)

$ 0.01

$ 0.01

$ 0.01

Common stock, authorized (in shares)

360,000,000

360,000,000

360,000,000

Common stock, par value per share (in usd per share)

$ 0.01

$ 0.01

$ 0.01

Preferred stock, issued (in shares)

0

0

0

Preferred stock, outstanding (in shares)

0

0

0

Authorized common stock available for repurchase (in shares)

1,010,877

1,010,877

3,000,000

Common stock repurchased (in shares)

599,066

446,502

1,114,701

Common stock repurchased, average cost per share (in usd per share)

$ 41.73

$ 34.86

$ 35.21

Minimum

Share-based Compensation Arrangement by Share-based Payment Award [Line Items]

Percentage of target shares granted

0.00%

Maximum

Share-based Compensation Arrangement by Share-based Payment Award [Line Items]

Percentage of target shares granted

200.00%

Performance Shares

Share-based Compensation Arrangement by Share-based Payment Award [Line Items]

Performance-based stock units, vested in period (in shares)

130,006

144,647

Performance period

3 years

3 years

3 years

Performance-based stock units, weighted average grant date fair value (in usd per share)

$ 66.97

$ 61

$ 66.97

$ 61

2005 Plan

Share-based Compensation Arrangement by Share-based Payment Award [Line Items]

Number of shares reserved for issuance (in shares)

3,362,304

4,050,000

Award vesting period (in years)

10 years

2005 Plan | Vesting period one

Share-based Compensation Arrangement by Share-based Payment Award [Line Items]

Award vesting period (in years)

3 years

2005 Plan | Vesting period two

Share-based Compensation Arrangement by Share-based Payment Award [Line Items]

Award vesting period (in years)

5 years

2005 Plan | Vesting period three

Share-based Compensation Arrangement by Share-based Payment Award [Line Items]

Award vesting period (in years)

10 years

2010 Plan

Share-based Compensation Arrangement by Share-based Payment Award [Line Items]

Common stock, authorized (in shares)

3,000,000

Number of shares reserved for issuance (in shares)

2,518,416

2010 Plan | Vesting period one

Share-based Compensation Arrangement by Share-based Payment Award [Line Items]

Award vesting period (in years)

3 years

2010 Plan | Vesting period two

Share-based Compensation Arrangement by Share-based Payment Award [Line Items]

Award vesting period (in years)

5 years

2010 Plan | Vesting period three

Share-based Compensation Arrangement by Share-based Payment Award [Line Items]

Award vesting period (in years)

10 years

1994 and 2005 Plans

Share-based Compensation Arrangement by Share-based Payment Award [Line Items]

Number of shares reserved for issuance (in shares)

3,362,304

2015 Plans

Share-based Compensation Arrangement by Share-based Payment Award [Line Items]

Number of shares reserved for issuance (in shares)

567,142

3,000,000

Shares available for grant under 2015 restricted stock plan (in shares)

567,142

2015 Plans | Vesting period one

Share-based Compensation Arrangement by Share-based Payment Award [Line Items]

Award vesting period (in years)

3 years

2015 Plans | Vesting period two

Share-based Compensation Arrangement by Share-based Payment Award [Line Items]

Award vesting period (in years)

4 years

2015 Plans | Vesting period three

Share-based Compensation Arrangement by Share-based Payment Award [Line Items]

Award vesting period (in years)

5 years

2015 Plans | Vesting period four

Share-based Compensation Arrangement by Share-based Payment Award [Line Items]

Award vesting period (in years)

10 years

2020 Plan

Share-based Compensation Arrangement by Share-based Payment Award [Line Items]

Number of shares reserved for issuance (in shares)

4,500,000

Shares available for grant under 2015 restricted stock plan (in shares)

3,270,415

3,270,415

2020 Plan | Vesting period one

Share-based Compensation Arrangement by Share-based Payment Award [Line Items]

Award vesting period (in years)

1 year

2020 Plan | Vesting period two

Share-based Compensation Arrangement by Share-based Payment Award [Line Items]

Award vesting period (in years)

2 years

2020 Plan | Vesting period three

Share-based Compensation Arrangement by Share-based Payment Award [Line Items]

Award vesting period (in years)

3 years

2020 Plan | Vesting period four

Share-based Compensation Arrangement by Share-based Payment Award [Line Items]

Award vesting period (in years)

4 years

ESPP

Share-based Compensation Arrangement by Share-based Payment Award [Line Items]

Common stock, authorized (in shares)

3,000,000

Percentage of the lower of the market related to purchase of common stock

85.00%

85.00%

Maximum employee subscription rate

15.00%

15.00%

Common stock reserved for future issuance under employee stock purchase plan (in shares)

2,257,649

2,257,649

Shares issued under employee stock purchase plan (in shares)

801,543

Weighted average purchase price of employees' purchase rights (in usd per share)

$ 31.74

Authorized shares of common a_4

Authorized shares of common and preferred stock and stock-based compensation plans - Schedule of Key Assumptions to Value Market-based Awards (Details) - Performance Shares - simulation simulation in Thousands	9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of simulations	100	100
Expected volatility	40.60%	27.41%
Expected life in years	2 years 11 months 12 days	2 years 11 months 1 day
Risk-free interest rate	0.21%	1.38%
Dividend yield	2.66%	2.32%

Segment and geographic inform_3

Segment and geographic information - Narrative (Details)	9 Months Ended
	Sep. 30, 2021regionsegment
Segment Reporting [Abstract]
Number of operating segments | segment	1
Number of geographic regions company operates in | region	3

Segment and geographic inform_4

Segment and geographic information - Schedule of Net Sales by Country (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020
Revenues from External Customers and Long-Lived Assets [Line Items]
Total revenue	$ 367,162	$ 308,124	$ 1,049,040	$ 918,834
Long-lived assets	309,000		309,000		$ 322,000
United States
Revenues from External Customers and Long-Lived Assets [Line Items]
Total revenue	141,000	121,000	388,000	355,000
Long-lived assets	127,000		127,000		127,000
China
Revenues from External Customers and Long-Lived Assets [Line Items]
Total revenue	59,000	52,000	172,000	139,000
Hungary
Revenues from External Customers and Long-Lived Assets [Line Items]
Long-lived assets	51,000		51,000		52,000
Malaysia
Revenues from External Customers and Long-Lived Assets [Line Items]
Long-lived assets	75,000		75,000		75,000
Rest of the World
Revenues from External Customers and Long-Lived Assets [Line Items]
Total revenue	167,000	$ 135,000	489,000	$ 425,000
Long-lived assets	$ 56,000		$ 56,000		$ 68,000

Debt - Narrative (Details)

Debt - Narrative (Details)	Jun. 18, 2021USD ($)	Sep. 30, 2021USD ($)
Credit Agreement
Line of Credit Facility [Line Items]
Total leverage ratio	3.50
Leverage ratio for material acquisitions	4
Debt instrument, covenant, liquidity ratio leverage, minimum	3
Wells Fargo Revolving Credit Loan
Line of Credit Facility [Line Items]
Debt issuance costs		$ 2,600,000
Secured Revolving Loan Facility | Credit Agreement
Line of Credit Facility [Line Items]
Unsecured revolving line of credit	$ 500,000,000
Revolving Credit Facility | Base Rate
Line of Credit Facility [Line Items]
Variable interest rate spread	0.50%
Revolving Credit Facility | LIBOR
Line of Credit Facility [Line Items]
Variable interest rate spread	1.00%
Revolving Credit Facility | Term Loan | Line of Credit
Line of Credit Facility [Line Items]
Unsecured revolving line of credit	$ 25,000,000
Revolving Credit Facility | Credit Agreement | Minimum
Line of Credit Facility [Line Items]
Quarterly commitment fee	0.15%
Revolving Credit Facility | Credit Agreement | Maximum
Line of Credit Facility [Line Items]
Quarterly commitment fee	0.25%
Revolving Credit Facility | Credit Agreement | Base Rate | Minimum
Line of Credit Facility [Line Items]
Variable interest rate spread	0.25%
Revolving Credit Facility | Credit Agreement | Base Rate | Maximum
Line of Credit Facility [Line Items]
Variable interest rate spread	0.75%
Revolving Credit Facility | Credit Agreement | LIBOR | Minimum
Line of Credit Facility [Line Items]
Variable interest rate spread	1.25%
Debt instrument, default interest rate	2.00%
Revolving Credit Facility | Credit Agreement | LIBOR | Maximum
Line of Credit Facility [Line Items]
Variable interest rate spread	1.75%

Debt - Schedule of Long-term De

Debt - Schedule of Long-term Debt Instruments (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Debt Instrument [Line Items]
Total Debt	$ 100,000	$ 98,750
Less: Unamortized debt issuance costs	0	(1,714)
Less: Current portion of total debt	0	(5,000)
Total Debt, non-current	$ 100,000	$ 92,036
Term Loan
Debt Instrument [Line Items]
Effective interest rate	1.70%	1.70%
Total Debt	$ 0	$ 98,750
Wells Fargo Revolving Credit Loan
Debt Instrument [Line Items]
Effective interest rate	1.30%
Total Debt	$ 100,000	$ 0

Commitments and contingencies -

Commitments and contingencies - Narrative (Details) $ in Millions	9 Months Ended
	Sep. 30, 2021USD ($)
Commitments and Contingencies Disclosure [Abstract]
Limited warranty on most hardware products (in number of years)	1 year
Non-cancelable purchase commitments	$ 3.2

Commitments and contingencies_2

Commitments and contingencies - Schedule Of Warranty Reserve (Details) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020
Movement in Standard Product Warranty Accrual [Roll Forward]
Balance at the beginning of the period	$ 2,872	$ 2,561
Accruals for warranties issued during the period	2,037	1,824
Accruals related to pre-existing warranties	(636)	405
Settlements made (in cash or in kind) during the period	(1,291)	(2,088)
Balance at the end of the period	$ 2,982	$ 2,702

Restructuring - Summary of Char

Restructuring - Summary of Charges in Consolidated Statement of Operations (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Restructuring Cost and Reserve [Line Items]
Total restructuring and other related costs	$ (111)	$ 658	$ 6,477	$ 13,461
Cost of sales
Restructuring Cost and Reserve [Line Items]
Total restructuring and other related costs	(7)	(13)	(50)	7
Research and development
Restructuring Cost and Reserve [Line Items]
Total restructuring and other related costs	65	38	444	4,716
Sales and marketing
Restructuring Cost and Reserve [Line Items]
Total restructuring and other related costs	(223)	512	3,924	8,055
General and administrative
Restructuring Cost and Reserve [Line Items]
Total restructuring and other related costs	$ 54	$ 121	$ 2,159	$ 683

Restructuring - Summary of Bala

Restructuring - Summary of Balance Sheet Activity (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Restructuring Reserve [Roll Forward]
Restructuring reserve, beginning balance			$ 28,993
Income statement expense	$ (111)	$ 658	6,477	$ 13,461
Cash payments			(30,389)
Restructuring reserve, ending balance	$ 5,081		$ 5,081

Restructuring - Narrative (Deta

Restructuring - Narrative (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Restructuring Cost and Reserve [Line Items]
Restructuring liability	$ 5,081	$ 28,993
Severance payments
Restructuring Cost and Reserve [Line Items]
Restructuring liability	$ 5,100

Acquisitions - Narrative (Detai

Acquisitions - Narrative (Details) - USD ($) $ in Thousands	Jul. 02, 2020	Jun. 30, 2020	Jun. 30, 2021	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020
Business Acquisition [Line Items]
Proceeds from term loan				$ 0	$ 70,000
Goodwill				$ 480,489		$ 467,547
Term loan facility | Wells Fargo Securities, LLC | Line of Credit
Business Acquisition [Line Items]
Proceeds from term loan		$ 70,000
OptimalPlus
Business Acquisition [Line Items]
Percentage of voting interests acquired	100.00%
Transaction costs						$ 7,000
Total cash consideration	$ 352,642
Cash acquired from acquisition	18,000
Deferred cash consideration	12,000
Goodwill	$ 205,038
Other Acquisitions
Business Acquisition [Line Items]
Total cash consideration			$ 20,000
Goodwill			17,000
Other intangible assets			$ 4,000

Acquisitions - Schedule of Prel

Acquisitions - Schedule of Preliminary Purchase Price Allocation (Details) - USD ($) $ in Thousands	Jul. 02, 2020	Sep. 30, 2021	Dec. 31, 2020
Business Acquisition [Line Items]
Goodwill		$ 480,489	$ 467,547
OptimalPlus
Business Acquisition [Line Items]
Consideration Transferred	$ 352,642
Cash	17,661
Intangible assets	129,000
Goodwill	205,038
Contract assets	15,454
Deferred revenue	(7,341)
Accounts receivable	4,927
Other assets and liabilities	(4,516)
Deferred tax liabilities	(7,581)
Net assets acquired	$ 352,642

Acquisitions - Summary of Preli

Acquisitions - Summary of Preliminary Purchase Price Allocation and Useful Lives (Details) - OptimalPlus $ in Thousands	Jul. 02, 2020USD ($)
Business Acquisition [Line Items]
Estimated Fair Value	$ 129,000
Customer relationships
Business Acquisition [Line Items]
Estimated Fair Value	$ 30,100
Estimated Useful Lives (in years)	5 years
Developed technology
Business Acquisition [Line Items]
Estimated Fair Value	$ 82,400
Estimated Useful Lives (in years)	6 years
In-process research and development (IPR&D)
Business Acquisition [Line Items]
Estimated Fair Value	$ 10,400
Estimated Useful Lives (in years)	6 years
Other intangibles
Business Acquisition [Line Items]
Estimated Fair Value	$ 6,100
Other intangibles | Minimum
Business Acquisition [Line Items]
Estimated Useful Lives (in years)	3 years
Other intangibles | Maximum
Business Acquisition [Line Items]
Estimated Useful Lives (in years)	5 years

Acquisitions - Pro Forma Inform

Acquisitions - Pro Forma Information (Details) - OptimalPlus - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
	Sep. 30, 2020	Sep. 30, 2020
Business Acquisition [Line Items]
Net sales	$ 309,142	$ 929,381
Net income	$ 4,907	$ 123,676

Subsequent events (Details)

Subsequent events (Details) - USD ($) $ / shares in Units, $ in Thousands	Oct. 19, 2021	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Oct. 26, 2021
Subsequent Event [Line Items]
Dividends declared per share (in usd per share)		$ 0.27	$ 0.26	$ 0.81	$ 0.78
Proceeds from revolving line of credit				$ 100,000	$ 20,000
Subsequent event
Subsequent Event [Line Items]
Dividends declared per share (in usd per share)	$ 0.27
Subsequent event | Minimum
Subsequent Event [Line Items]
Current estimate of pre-tax charges						$ 8,000
Subsequent event | Maximum
Subsequent Event [Line Items]
Current estimate of pre-tax charges						$ 9,000
Subsequent event | Secured Revolving Loan Facility | Credit Agreement
Subsequent Event [Line Items]
Proceeds from revolving line of credit	$ 200,000
Subsequent event | Corporation Specializing In High Power Test And Measurement Applications
Subsequent Event [Line Items]
Total cash consideration	200,000
Cash acquired from acquisition	$ 3,000