National Instruments (NATI) 10-Q 2 Nov 20 2020 Q3 Quarterly report Financial data

Cover

Cover - shares	9 Months Ended
	Sep. 30, 2020	Oct. 29, 2020
Cover [Abstract]
Document Type	10-Q
Document Quarterly Report	true
Document Period End Date	Sep. 30, 2020
Document Transition Report	false
Entity File Number	0-25426
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
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
Title of 12(b) Security	Common Stock, $0.01 par value
Entity Common Stock, Shares Outstanding (in shares)		131,245,640
Entity Central Index Key	0000935494
Current Fiscal Year End Date	--12-31
Document Fiscal Year Focus	2020
Document Fiscal Period Focus	Q3
Amendment Flag	false

Consolidated Balance Sheets

Consolidated Balance Sheets - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Current assets:
Cash and cash equivalents	$ 197,319	$ 194,616
Short-term investments	92,853	237,983
Accounts receivable, net	214,620	248,872
Inventories, net	209,558	200,410
Prepaid expenses and other current assets	72,956	65,477
Total current assets	787,306	947,358
Property and equipment, net	253,073	243,717
Goodwill	487,101	262,242
Intangible assets, net	183,067	84,083
Operating lease right-of-use assets	69,395	70,407
Other long-term assets	63,930	44,082
Total assets	1,843,872	1,651,889
Current liabilities:
Accounts payable and accrued expenses	48,886	52,192
Accrued compensation	53,496	47,732
Deferred revenue - current	116,871	131,445
Operating lease liabilities - current	16,177	13,431
Other taxes payable	41,604	40,607
Debt, current	3,500	0
Other current liabilities	50,259	20,716
Total current liabilities	330,793	306,123
Deferred income taxes	41,514	14,065
Income tax payable - non-current	61,628	69,151
Liability for uncertain tax positions	6,867	6,652
Deferred revenue - non-current	34,210	33,480
Operating lease liabilities - non-current	37,767	40,650
Debt, non-current	84,289	0
Other long-term liabilities	7,606	5,418
Total liabilities	604,674	475,539
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; 131,245,640 shares and 130,504,535 shares issued and outstanding, respectively	1,312	1,305
Additional paid-in capital	1,012,656	953,578
Retained earnings	247,970	242,537
Accumulated other comprehensive loss	(22,740)	(21,070)
Total stockholders’ equity	1,239,198	1,176,350
Total liabilities and stockholders’ equity	$ 1,843,872	$ 1,651,889

Consolidated Balance Sheets (Pa

Consolidated Balance Sheets (Parenthetical) - $ / shares	Sep. 30, 2020	Dec. 31, 2019
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)	131,245,640	130,504,535
Common stock, outstanding (in shares)	131,245,640	130,504,535

Consolidated Statements Of Inco

Consolidated Statements Of Income - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Net sales:
Total net sales	$ 308,124	$ 340,442	$ 918,834	$ 985,747
Cost of sales:
Total cost of sales	92,263	85,915	261,925	245,756
Gross profit	215,861	254,527	656,909	739,991
Operating expenses:
Sales and marketing	109,774	113,922	330,939	352,340
Research and development	70,802	66,558	206,648	200,981
General and administrative	37,431	35,711	92,980	92,639
Total operating expenses	218,007	216,191	630,567	645,960
Gain on sale of business/asset	0	26,842	159,753	26,842
Operating (loss) income	(2,146)	65,178	186,095	120,873
Other Nonoperating Income (Expense) [Abstract]
Other (expense) income	(2,001)	2,249	(2,584)	5,379
Income before income taxes	(4,147)	67,427	183,511	126,252
Provision for income taxes	475	15,783	44,588	22,697
Net (loss) income	$ (4,622)	$ 51,644	$ 138,923	$ 103,555
Basic (loss) earnings per share (in usd per share)	$ (0.04)	$ 0.39	$ 1.06	$ 0.79
Weighted average shares outstanding - basic (in shares)	131,419	131,385	131,017	131,896
Diluted (loss) earnings per share (in usd per share)	$ (0.04)	$ 0.39	$ 1.06	$ 0.78
Weighted average shares outstanding - diluted (in shares)	131,419	131,889	131,671	132,890
Dividends declared per share (in usd per share)	$ 0.26	$ 0.25	$ 0.78	$ 0.75
Product
Net sales:
Total net sales	$ 269,651	$ 305,247	$ 809,890	$ 882,747
Cost of sales:
Total cost of sales	88,370	84,127	254,236	240,056
Software maintenance
Net sales:
Total net sales	38,473	35,195	108,944	103,000
Cost of sales:
Total cost of sales	$ 3,893	$ 1,788	$ 7,689	$ 5,700

Consolidated Statements Of Comp

Consolidated Statements Of Comprehensive Income - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Statement of Comprehensive Income [Abstract]
Net (loss) income	$ (4,622)	$ 51,644	$ 138,923	$ 103,555
Other comprehensive income (loss), before tax and net of reclassification adjustments:
Foreign currency translation adjustment	8,483	(8,500)	6,507	(9,303)
Unrealized (loss) gain on securities available-for-sale	(163)	(419)	(317)	1,494
Unrealized (loss) gain on derivative instruments	(9,530)	1,627	(10,128)	1,359
Other comprehensive (loss) income, before tax	(1,210)	(7,292)	(3,938)	(6,450)
Tax (benefit) expense related to items of other comprehensive income	(2,335)	414	(2,268)	355
Other comprehensive income (loss), net of tax	1,125	(7,706)	(1,670)	(6,805)
Comprehensive (loss) income	$ (3,497)	$ 43,938	$ 137,253	$ 96,750

Consolidated Statements Of Cash

Consolidated Statements Of Cash Flows - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019
Cash flow from operating activities:
Net income	$ 138,923	$ 103,555
Adjustments to reconcile net income to net cash provided by operating activities:
Disposal gain on sale of business/asset	(159,753)	(26,842)
Depreciation and amortization	61,228	54,546
Stock-based compensation	42,556	38,054
Deferred income taxes	(932)	(1,461)
Changes in operating assets and liabilities	26,762	(18,507)
Net cash provided by operating activities	108,784	149,345
Cash flow from investing activities:
Acquisitions, net of cash acquired	(334,981)	0
Capital expenditures	(36,573)	(47,183)
Proceeds from sale of assets/business, net of cash divested	160,266	32,492
Capitalization of internally developed software	(2,806)	(7,179)
Additions to other intangibles	(1,045)	(1,132)
Acquisitions of equity-method investments	(7,502)	(13,670)
Purchases of short-term investments	(206,330)	(141,074)
Sales and maturities of short-term investments	351,597	204,046
Net cash (used in) provided by investing activities	(77,374)	26,300
Cash flow from financing activities:
Proceeds from revolving line of credit	20,000	0
Proceeds from term loan	70,000	0
Payments on term loan	(875)	0
Debt issuance costs	(1,480)	0
Proceeds from issuance of common stock	24,971	25,823
Repurchase of common stock	(39,244)	(137,171)
Dividends paid	(102,396)	(99,083)
Net cash used in financing activities	(29,024)	(210,431)
Effect of exchange rate changes on cash	317	(1,827)
Net change in cash and cash equivalents	2,703	(36,613)
Cash and cash equivalents at beginning of period	194,616	259,386
Cash and cash equivalents at end of period	$ 197,319	$ 222,773

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, 2018			132,655,941
Beginning Balance at Dec. 31, 2018		$ 1,238,358	$ 1,327	$ 897,544	$ 356,418	$ (16,931)
Net income		103,555			103,555
Other comprehensive income (loss), net of tax		(6,805)				(6,805)
Issuance of common stock under employee plans (in shares)			1,608,832
Issuance of common stock under employee plans, including tax benefits		25,823	$ 16	25,807
Stock-based compensation		37,484		37,484
Repurchase of common stock (in shares)			(3,205,676)
Repurchase of common stock		(137,171)	$ (32)	(21,714)	(115,425)
Dividends paid	[1]	(99,083)			(99,083)
Ending Balance (in shares) at Sep. 30, 2019			131,059,097
Ending Balance at Sep. 30, 2019		1,162,161	$ 1,311	939,121	245,465	(23,736)
Beginning Balance (in shares) at Jun. 30, 2019			131,884,775
Beginning Balance at Jun. 30, 2019		1,174,574	$ 1,319	924,801	264,484	(16,030)
Net income		51,644			51,644
Other comprehensive income (loss), net of tax		(7,706)				(7,706)
Issuance of common stock under employee plans (in shares)			230,400
Issuance of common stock under employee plans, including tax benefits		8,178	$ 3	8,175
Stock-based compensation		13,284		13,284
Repurchase of common stock (in shares)			(1,056,078)
Repurchase of common stock		(44,797)	$ (11)	(7,139)	(37,647)
Dividends paid	[1]	(33,016)			(33,016)
Ending Balance (in shares) at Sep. 30, 2019			131,059,097
Ending Balance at Sep. 30, 2019		$ 1,162,161	$ 1,311	939,121	245,465	(23,736)
Beginning Balance (in shares) at Dec. 31, 2019		130,504,535	130,504,535
Beginning Balance at Dec. 31, 2019		$ 1,176,350	$ 1,305	953,578	242,537	(21,070)
Net income		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, including tax benefits		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	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)
Net income		(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, including tax benefits		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	131,245,640
Ending Balance at Sep. 30, 2020		$ 1,239,198	$ 1,312	$ 1,012,656	$ 247,970	$ (22,740)
[1]	Cash dividends declared per share of common stock were $0.25 for the three months ended September 30, 2019, and $0.75 for the nine months ended September 30, 2019.

Consolidated Statements of St_2

Consolidated Statements of Stockholders' Equity (Parenthetical) - $ / shares	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Statement of Stockholders' Equity [Abstract]
Dividends declared per share (in usd per share)	$ 0.26	$ 0.25	$ 0.78	$ 0.75

Basis of presentation

Basis of presentation	9 Months Ended
	Sep. 30, 2020
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, 2019, included in our Annual Report on Form 10-K filed with the Securities and Exchange Commission ("SEC") on February 20, 2020 (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, 2020 and December 31, 2019, the results of our operations and comprehensive income for three and nine months ended September 30, 2020 and 2019, our cash flows for the nine months ended September 30, 2020 and 2019 and our statement of stockholders' equity for the three and nine months ended September 30, 2020 and 2019. Our operating results for the three and nine months ended September 30, 2020 are not necessarily indicative of the results that may be expected for the year ending December 31, 2020. These financial statements have been prepared in accordance with accounting principles generally accepted in the United States. Reclassifications As further discussed below, certain prior period amounts have been reclassified to conform to the current period presentation. The reclassifications had no impact on our previously reported net income or cash flows: • Before the second quarter of 2020, we included net sales attributable to our operations in India within the EMEIA region in Note 2 - Revenue of Notes to Consolidated Financial Statements. In the second quarter of 2020, we began including these amounts within the APAC (Australia, India, New Zealand, Southeast Asia, China, South Korea and Japan) geographic region, to reflect recent changes within our organizational structure. We have recast historical comparative information to conform to the September 30, 2020 presentation. Refer to Note 2 - Revenue of Notes to Consolidated Financial Statements for our revenue disaggregated by geographic region which now include the Americas (United States, Canada and Latin America), EMEA (Europe, Middle East, and Africa) and APAC. • Before the second quarter of 2020, we presented “Interest income”, "Net foreign exchange gain (loss)", and "Other income (loss)" separately on the consolidated statements of income. In the second quarter of 2020, we began presenting these amounts within “Other (expense) income” in the consolidated statements of income for all periods presented. Refer to "Other (expense) income" in Note 1 - Basis of Presentation of Notes to Consolidated Financial Statements for additional information on the amounts that comprise "Other (expense) income". Recently Adopted Accounting Pronouncements Current Expected Credit Losses ("CECL") In June 2016, the Financial Accounting Standards Board ("FASB") issued ASU No. 2016-13, "Financial Instruments—Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments." The ASU replaces the incurred-loss impairment methodology and requires immediate recognition of estimated credit losses expected to occur for most financial assets, including trade receivables. Credit losses on available-for-sale debt securities with unrealized losses will be recognized as allowances for credit losses limited to the amount by which fair value is below amortized cost. We adopted the new standard on January 1, 2020 and the impact of the adoption was not material to our consolidated financial statements as credit losses are not expected to be significant based on historical collection trends, the financial condition of payment partners, and external market factors. We will continue to actively monitor the impact of the recent coronavirus (COVID-19) pandemic on expected credit losses. Implementation Costs Incurred in a Cloud Computing Arrangement In August 2018, the FASB issued ASU 2018-15, “Customer’s Accounting for Implementation Costs Incurred in a Cloud Computing Arrangement That Is a Service Contract,” which clarifies the accounting for implementation costs in cloud computing arrangements. The new standard aligns the treatment of implementation costs incurred by customers in cloud computing arrangements that are service contracts with the treatment of similar costs incurred to develop or obtain internal-use software. Under the new standard, implementation costs are deferred and presented in the same financial statement caption on the condensed consolidated balance sheet as a prepayment of related arrangement fees. The deferred costs are recognized over the term of the arrangement in the same financial statement caption in the condensed consolidated income statement as the related fees of the arrangement. We adopted the new standard on January 1, 2020. The new standard did not have a material impact on our consolidated financial statements and related disclosures. Fair Value Measurements In August 2018, the FASB issued ASU 2018-13, “Disclosure Framework — Changes to the Disclosure Requirements for Fair Value Measurement,” which modifies the disclosure requirements on fair value measurements. We adopted the new standard on January 1, 2020. The new standard did not have a material impact on our consolidated financial statements and related disclosures. Income Taxes In December 2019, the FASB issued ASU 2019-12, “Income Taxes — Simplifying the Accounting for Income Taxes (Topic 740),” which simplifies the accounting for income taxes by removing certain exceptions to the general principles in Topic 740. The amendments in this ASU also improve consistency and simplify other areas of Topic 740 by clarifying and amending existing guidance. The amendments in this ASU will be applied using different approaches depending on what the specific amendment relates to and, for public entities, are effective for fiscal years, and interim periods within those fiscal years, beginning after December 15, 2020. An entity is permitted to early adopt the guidance, and we early adopted ASU 2019-12 as of January 1, 2020. The adoption did not have a material impact on our consolidated financial statements and related disclosures. Disclosures about Acquired and Disposed Businesses In May 2020, the SEC adopted Release No. 33-10786 "Amendments to Financial Disclosures about Acquired and Disposed Businesses" ("Release No. 33-10786") which includes amendments to certain of its rules and forms related to the disclosure of financial information regarding acquired or disposed businesses. Among other changes, the amendments impact SEC rules relating to (1) the definition of “significant” subsidiaries, (2) requirements to provide financial statements for “significant” acquisitions, and (3) revisions to the formulation and usage of pro forma financial information. Release No. 33-10786 is effective on January 1, 2021, however, voluntary early adoption is permitted as long as all amendments are adopted in their entirety. We elected to early adopt all provisions of Release No. 33-10786 during the second quarter of 2020. Summary of Significant Accounting Policies As discussed above, we adopted the new expected credit loss standard as of January 1, 2020. There were no other significant changes in our accounting policies during the three and nine months ended September 30, 2020 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/asset" 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) income, net consisted of the following amounts (in thousands): Three Months Ended September 30, Nine Months Ended September 30, (Unaudited) (Unaudited) 2020 2019 2020 2019 Interest income $ 414 $ 1,930 $ 3,724 $ 6,187 Interest expense (973) — (1,115) — Loss from equity-method investments (627) (239) (2,559) (406) Net foreign exchange loss (676) (378) (2,019) (1,623) Other (139) 936 (615) 1,221 Other (expense) income, net $ (2,001) $ 2,249 $ (2,584) $ 5,379 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, 2020 and 2019, are as follows (in thousands):  Three Months Ended September 30, Nine Months Ended September 30,  (Unaudited) (Unaudited)  2020 2019 2020 2019 Weighted average shares outstanding-basic 131,419 131,385 131,017 131,896 Plus: Common share equivalents RSUs — 504 654 994 Weighted average shares outstanding-diluted 131,419 131,889 131,671 132,890 Stock awards to acquire 3,490,700 shares and 1,611,000 shares for the three months ended September 30, 2020 and 2019, respectively, and 276,000 shares and 568,000 shares for the nine months ended September 30, 2020 and 2019, 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 (in thousands): As of September 30, 2020 As of December 31, (unaudited) 2019 Income taxes payable - current $ 23,487 $ 6,791 Other 26,772 13,925 Total $ 50,259 $ 20,716

Revenue

Revenue	9 Months Ended
	Sep. 30, 2020
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. Before the second quarter of 2020, we included net sales attributable to our operations in India within the EMEIA region. In the second quarter of 2020, we began including these amounts within the APAC geographic region, to reflect recent changes within our organizational structure. We have recast historical comparative information to conform to the September 30, 2020 presentation. The geographic regions are now presented as the Americas, EMEA and APAC to reflect this change. Total net sales based on the disaggregation criteria described above are as follows:  Three Months Ended September 30, (In thousands) (Unaudited)  2020 2019 Net sales: Point-in-Time (1) Over Time Total Point-in-Time (1) Over Time Total Americas $ 107,808 $ 19,241 $ 127,049 $ 119,895 $ 23,222 $ 143,117 EMEA 57,988 20,551 78,539 70,076 19,662 89,738 APAC 92,050 10,486 102,536 98,161 9,426 107,587 Total net sales (1) $ 257,846 $ 50,278 $ 308,124 $ 288,132 $ 52,310 $ 340,442 (1) Net sales contains hedging gains and losses, which do not represent revenues recognized from customers.  Nine Months Ended September 30, (In thousands) (Unaudited)  2020 2019 Net sales: Point-in-Time (1) Over Time Total Point-in-Time (1) Over Time Total Americas $ 316,220 $ 57,554 $ 373,774 $ 325,349 $ 69,337 $ 394,686 EMEA 181,330 58,594 239,924 216,644 57,411 274,055 APAC 274,341 30,795 305,136 290,140 26,866 317,006 Total net sales (1) $ 771,891 $ 146,943 $ 918,834 $ 832,133 $ 153,614 $ 985,747 (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, 2020 were as follows:  Amount  (In thousands) Balance as of December 31, 2019 $ 164,925 Deferral of revenue billed in current period, net of recognition 95,934 Recognition of revenue deferred in prior periods (103,274) Acquisitions/Divestitures (7,955) Foreign currency translation impact 1,451 Balance as of September 30, 2020 (unaudited) $ 151,081 For the nine months ended September 30, 2020, 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" and "Other long-term 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, 2020, amounts recognized 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 excluding contracts where revenue is recognized as invoiced, was approximately $84 million as of September 30, 2020. 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, 2020, we expect to recognize approximately 15% of the revenue related to these unsatisfied performance obligations during the remainder of 2020, 43% during 2021, and 42% thereafter.

Short-term investments

Short-term investments	9 Months Ended
	Sep. 30, 2020
Cash, Cash Equivalents, and Short-term Investments [Abstract]
Short-term investments	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, 2020 (In thousands) (Unaudited)  Gross Gross  Adjusted Cost Unrealized Gain Unrealized Loss Fair Value Corporate bonds $ 92,610 $ 245 $ (2) $ 92,853 Total Short-term investments $ 92,610 $ 245 $ (2) $ 92,853 (In thousands) As of December 31, 2019  Gross Gross  Adjusted Cost Unrealized Gain Unrealized Loss Fair Value Corporate bonds $ 237,423 $ 628 $ (68) $ 237,983 Total Short-term investments $ 237,423 $ 628 $ (68) $ 237,983 The following tables summarize the contractual maturities of our short-term investments designated as available-for-sale debt securities:  As of September 30, 2020 (In thousands) (Unaudited)  Adjusted Cost Fair Value Due in less than 1 year $ 88,194 $ 88,438 Due in 1 to 5 years 4,416 4,415 Total available-for-sale debt securities $ 92,610 $ 92,853  Due in less than 1 year Adjusted Cost Fair Value Corporate bonds $ 88,194 $ 88,438 Total available-for-sale debt securities $ 88,194 $ 88,438  Due in 1 to 5 years Adjusted Cost Fair Value Corporate bonds $ 4,416 $ 4,415 Total available-for-sale debt securities $ 4,416 $ 4,415 Equity-Method Investments

Fair value measurements

Fair value measurements	9 Months Ended
	Sep. 30, 2020
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, 2020 Quoted Prices in Active Markets for Identical Assets (Level 1) Significant Other Observable Inputs (Level 2) Significant Unobservable Inputs (Level 3) Assets Cash and cash equivalents available for sale: Money Market Funds $ 82,730 $ 82,730 $ — $ — Short-term investments available for sale: Corporate notes and bonds 92,853 — 92,853 — Derivatives 5,363 — 5,363 — Total Assets $ 180,946 $ 82,730 $ 98,216 $ —  Liabilities Derivatives $ (10,777) $ — $ (10,777) $ — Total Liabilities $ (10,777) $ — $ (10,777) $ — (In thousands) Fair Value Measurements at Reporting Date Using Description December 31, 2019 Quoted Prices in Active Markets for Identical Assets (Level 1) Significant Other Observable Inputs (Level 2) Significant Unobservable Inputs (Level 3) Assets Cash and cash equivalents available for sale: Money Market Funds $ 87,397 $ 87,397 $ — $ — Corporate notes and bonds 9,962 — 9,962 — Short-term investments available for sale: Corporate bonds 237,983 — 237,983 — Derivatives 8,209 — 8,209 — Total Assets $ 343,551 $ 87,397 $ 256,154 $ —  Liabilities Derivatives $ (2,872) $ — $ (2,872) $ — Total Liabilities $ (2,872) $ — $ (2,872) $ — 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. 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, 2020. There were no transfers in or out of Level 1 or Level 2 during the nine months ended September 30, 2020. As of September 30, 2020, our short-term investments did not include sovereign debt from any country other than the United States. The majority of our short-term investments that are located outside of the U.S. are denominated in the U.S. dollar with the exception of $5 million U.S. dollar equivalent of corporate bonds that are denominated in Euro. We did not have any items that were measured at fair value on a nonrecurring basis at September 30, 2020 and December 31, 2019. 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, 2020
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 operations in approximately 45 countries. Sales outside of the Americas accounted for approximately 59% and 58% of our net sales during the three months ended September 30, 2020 and 2019, and approximately 59% and 60% the nine months ended September 30, 2020 and 2019, 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 purchase 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 purchase 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 are 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, 2020 As of December 31,  (Unaudited) 2019 British pound $ 23,251 $ 13,988 Chinese yuan 57,943 32,970 Euro 209,385 130,122 Hungarian forint 89,962 95,228 Japanese yen 83,503 53,527 Korean won 26,918 24,728 Malaysian ringgit 41,681 32,725 Total forward contracts notional amount $ 532,643 $ 383,288 The contracts in the foregoing table had contractual maturities of 36 months or less at September 30, 2020 and December 31, 2019. At September 30, 2020, we expect to reclassify $0.6 million of losses on derivative instruments from accumulated OCI to net sales during the next twelve months when the hedged international sales occur, $1.4 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 $1.0 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, 2020. Actual results may vary materially as a result of changes in the corresponding exchange rates subsequent to this date. The gains and losses recognized in earnings due to hedge ineffectiveness were not material for each of the nine months ended September 30, 2020 and 2019 and are included as a component of net income under the line item “Other (expense) income.” Other Derivatives Other derivatives not designated as hedging instruments consist primarily of foreign currency forward contracts that we use to hedge our foreign denominated net receivable or net payable positions 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) income.” As of September 30, 2020 and December 31, 2019, we held foreign currency forward contracts that were not designated as hedging instruments with a notional amount of $87 million and $41 million, respectively. The following tables present the fair value of derivative instruments on our Consolidated Balance Sheets at September 30, 2020 and December 31, 2019, respectively.  Asset Derivatives  September 30, 2020 December 31, 2019 (In thousands) (Unaudited)  Balance Sheet Location Fair Value Balance Sheet Location Fair Value Derivatives designated as hedging instruments Foreign exchange contracts - ST forwards Prepaid expenses and other current assets $ 2,314 Prepaid expenses and other current assets $ 7,039 Foreign exchange contracts - LT forwards Other long-term assets 2,639 Other long-term assets 970 Total derivatives designated as hedging instruments $ 4,953 $ 8,009 Derivatives not designated as hedging instruments Foreign exchange contracts - ST forwards Prepaid expenses and other current assets $ 411 Prepaid expenses and other current assets $ 200 Total derivatives not designated as hedging instruments $ 411 $ 200 Total derivatives $ 5,364 $ 8,209  Liability Derivatives  September 30, 2020 December 31, 2019 (In thousands) (Unaudited)  Balance Sheet Location Fair Value Balance Sheet Location Fair Value Derivatives designated as hedging instruments Foreign exchange contracts - ST forwards Other current liabilities $ (5,305) Other current liabilities $ (2,089)  Foreign exchange contracts - LT forwards Other long-term liabilities (4,230) Other long-term liabilities (351) Total derivatives designated as hedging instruments $ (9,535) $ (2,440)  Derivatives not designated as hedging instruments  Foreign exchange contracts - ST forwards Other current liabilities $ (1,241) Other current liabilities $ (432) Total derivatives not designated as hedging instruments $ (1,241) $ (432)  Total derivatives $ (10,776) $ (2,872) The following tables present the effect of derivative instruments on our Consolidated Statements of Income for the three months ended September 30, 2020 and 2019, respectively: 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 1,144 Operating expenses (266) Total $ (9,531) $ (380) September 30, 2019 (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 $ 6,736 Net sales $ 3,291  Foreign exchange contracts - forwards (2,946) Cost of sales (176)  Foreign exchange contracts - forwards (2,163) Operating expenses (112) Total $ 1,627 $ 3,003 (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, 2020 September 30, 2019  (Unaudited) (Unaudited) Foreign exchange contracts - forwards Other expense (income) $ (267) 287  Total $ (267) $ 287 The following tables present the effect of derivative instruments on our Consolidated Statements of Income for the nine months ended September 30, 2020 and 2019, respectively: 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 September 30, 2019 (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 $ 7,186 Net sales $ 7,687  Foreign exchange contracts - forwards (3,386) Cost of sales (217)  Foreign exchange contracts - forwards (2,441) Operating expenses (158) Total $ 1,359 $ 7,312 (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, 2020 September 30, 2019  (Unaudited) (Unaudited) Foreign exchange contracts - forwards Other income (expense) $ (163) (82) Total $ (163) $ (82)

Inventories, net

Inventories, net	9 Months Ended
	Sep. 30, 2020
Inventory Disclosure [Abstract]
Inventories, net	Inventories, net Inventories, net consist of the following:  September 30, 2020 December 31, (In thousands) (Unaudited) 2019  Raw materials $ 110,773 $ 110,078 Work-in-process 12,235 10,613 Finished goods 86,550 79,719 Total $ 209,558 $ 200,410

Intangible assets and goodwill,

Intangible assets and goodwill, net	9 Months Ended
	Sep. 30, 2020
Goodwill and Intangible Assets Disclosure [Abstract]
Intangible assets and goodwill, net	Intangible assets and goodwill, net Intangible assets at September 30, 2020 and December 31, 2019 are as follows:  September 30, 2020 (In thousands) (Unaudited) December 31, 2019  Gross Carrying Amount Accumulated Amortization Net Carrying Amount Gross Carrying Amount Accumulated Amortization Net Carrying Amount Capitalized software development costs $ 123,483 $ (86,096) $ 37,387 $ 132,789 $ (76,910) $ 55,879 Acquired technology 105,008 (14,726) 90,282 91,900 (87,917) 3,983 Patents 36,531 (26,008) 10,523 35,609 (23,993) 11,616 Other 74,671 (29,796) 44,875 44,490 (31,885) 12,605 Total $ 339,693 $ (156,626) $ 183,067 $ 304,788 $ (220,705) $ 84,083 Software development costs capitalized for the three months ended September 30, 2020 and 2019 were $(0.2) million and $2.8 million, respectively, and related amortization expense was $6.9 million and $7.1 million, respectively. For the nine months ended September 30, 2020 and 2019, capitalized software development costs were $3.1 million and $7.5 million, respectively, and related amortization expense was $21.6 million and $20.9 million, respectively. Capitalized software development costs for the three months ended September 30, 2020 and 2019 included costs related to stock-based compensation of $0.1 million and $0.2 million, respectively. For each of the nine months ended September 30, 2020 and 2019, capitalized software development costs included costs related to stock-based compensation of $0.3 million. 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, generally three three Goodwill The carrying amount of goodwill as of September 30, 2020, was as follows:  Amount  (In thousands) Balance as of December 31, 2019 $ 262,242 Acquisition 227,280 Foreign currency translation impact 4,800 Divestiture (7,221) Balance as of September 30, 2020 (unaudited) $ 487,101

Leases

Leases	9 Months Ended
	Sep. 30, 2020
Leases [Abstract]
Leases	Leases We have operating leases for corporate offices, automobiles, and certain equipment. Our leases have remaining terms of 1 year to 94 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, 2020 September 30, 2019 September 30, 2020 September 30, 2019 Operating Lease Cost (a) $ 4,869 $ 5,456 $ 15,941 $ 16,951 (a) includes variable and short-term lease costs Maturities of lease liabilities as of September 30, 2020 were as follows (unaudited): (In thousands) Years ending December 31, Operating Leases 2020 (Excluding the nine months ended September 30, 2020) $ 7,012 2021 17,340 2022 11,465 2023 8,229 2024 7,062 Thereafter 14,161 Total future minimum lease payments 65,269 Less imputed interest (11,325) Total $ 53,944 As of September 30, 2020, we have additional operating leases, that have not commenced during the nine months ended September 30, 2020, which were not material.

Income taxes

Income taxes	9 Months Ended
	Sep. 30, 2020
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 $102 million and $86 million at September 30, 2020 and December 31, 2019, respectively. A majority of the valuation allowance is related to the deferred tax assets of National Instruments Hungary Kft. ("NI Hungary"). 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 $6.9 million and $6.7 million of unrecognized tax benefits at September 30, 2020 and December 31, 2019, respectively, all of which would affect our effective income tax rate if recognized. We recorded no change in unrecognized tax benefits for the three months ended September 30, 2020, as a result of the tax positions taken during prior periods. As of September 30, 2020, it is reasonably possible that we will recognize tax benefits in the amount of $2.9 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. As of September 30, 2020, we had approximately $0.8 million accrued for interest related to uncertain tax positions. The tax years 2013 through 2020 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 (11)% and 23% for the three months ended September 30, 2020 and 2019, respectively, and 24% and 18% for the nine months ended September 30, 2020 and 2019, respectively. For the three months ended September 30, 2020, our effective tax rate was higher than the U.S. federal statutory rate of 21% as a result of state income taxes net of federal benefit, nondeductible officer compensation, the net effect of non-permanent investment in foreign jurisdictions, nondeductible acquisition costs and the change in intercompany prepaid tax asset, offset by the research and development tax credit, an enhanced deduction for certain research and development expenses, and the deduction for foreign-derived deduction eligible income. For the nine months ended September 30, 2020, our effective tax rate was higher than the U.S. federal statutory rate of 21% as a result of state income taxes net of federal benefit, nondeductible officer compensation, the net effect of non-permanent investment in foreign jurisdictions, nondeductible acquisition costs, the change in intercompany prepaid tax asset and the gain on the sale of our AWR business, offset by the research and development tax credit, an enhanced deduction for certain research and development expenses, and the deduction for foreign-derived deduction eligible income. For the three months ended September 30, 2019, our effective tax rate was higher than the U.S. federal statutory rate of 21% as a result of state income taxes, the U.S. tax on global intangible low-taxed income, nondeductible officer compensation, and an adjustment to the one-time transition tax on deferred foreign income, offset by the research and development tax credit, an enhanced deduction for certain research and development expenses, a decrease in unrecognized tax benefits resulting from the closing of open tax years, and the deduction for foreign-derived deduction eligible income. For the nine months ended September 30, 2019, our effective tax rate was lower than the U.S. federal statutory rate of 21% as a result of an enhanced deduction for certain research and development expenses, a decrease in unrecognized tax benefits resulting from the closing of open tax years, the research and development tax credit, excess tax benefits from share-based compensation, a tax benefit from disqualifying dispositions of equity awards that do not ordinarily result in a tax benefit, and the deduction for foreign-derived deduction eligible income, offset by state income taxes, the U.S. tax on global intangible low-taxed income, nondeductible officer compensation, and an adjustment to the one-time transition tax on deferred foreign income. Our earnings 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 expense of $0.1 million and $0.3 million for the three and nine months ended September 30, 2020, respectively, and income tax benefits of $1.6 million and $4.2 million for the three and nine months ended September 30, 2019, 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, 2020 were approximately $0.2 million and $0.4 million, respectively. The income tax benefits of the tax holiday for the three and nine months ended September 30, 2019 were approximately $1.8 million and $3.1 million, respectively. The impact of the tax holiday on a per share basis for the three and nine months ended September 30, 2020 was a benefit of $0.01 per share. The impact of the tax holiday on a per share basis for the three and nine months ended September 30, 2019 was a benefit of $0.01 and $0.02 per share, respectively.

Comprehensive Income

Comprehensive Income	9 Months Ended
	Sep. 30, 2020
Accumulated Other Comprehensive Income (Loss), Net of Tax [Abstract]
Comprehensive income	Comprehensive income Our comprehensive income is comprised of net income, foreign currency translation, 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, 2020 and 2019, consisted of the following:  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) expense — (45) (2,223) (2,268) Balance as of September 30, 2020 $ (19,324) $ (357) $ (3,059) $ (22,740)  September 30, 2019  (Unaudited) (In thousands) Currency translation adjustment Investments Derivative instruments Accumulated other comprehensive income/(loss) Balance as of December 31, 2018 $ (22,485) $ (1,308) 6,862 $ (16,931) Current-period other comprehensive (loss) income (9,303) 1,494 8,671 862 Reclassified from accumulated OCI into income — — (7,312) (7,312) Income tax (benefit) expense — (11) 366 355 Balance as of September 30, 2019 $ (31,788) $ 197 $ 7,855 $ (23,736) ໿

Authorized shares of common and

Authorized shares of common and preferred stock and stock-based compensation plans	9 Months Ended
	Sep. 30, 2020
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 Following approval by the Company’s Board of Directors and stockholders, on May 14, 2013, the Company’s certificate of incorporation was amended to increase the authorized shares of common stock by 180,000,000 shares to a total of 360,000,000 shares. As a result of this amendment, the total number of shares which the Company is 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. Restricted stock unit plans Our stockholders approved our 2005 Incentive Plan (the “2005 Plan”) in May 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 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 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 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, 2005, and the 2010 Plans 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 2005, 2010, and 2015 Plans as a result of the forfeiture or termination of 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 three Performance-based stock units During the nine months ended September 30, 2020 and 2019, we granted 144,647 and 92,809 PRSUs, respectively, of performance-based restricted stock units (“PRSUs”) to executive officers pursuant to the 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, 2020, the three-year performance period commenced on January 1, 2020, and will end on December 31, 2022, and for the PRSUs granted during the nine months ended September 30, 2019, the three The fair values of PRSUs are estimated using a Monte Carlo simulation. The determination of fair value of the PRSUs are 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, 2020 September 30, 2019 Number of simulations 100,000 100,000 Expected volatility 27.41% 26.08% Expected life in years 2.92 years 2.94 years Risk-free interest rate 1.38% 2.52% Dividend yield 2.32% 1.96% The weighted average grant date fair value of the market-based awards, as determined by the Monte Carlo valuation model, was $61.00 per share and $57.46 per share in 2020 and 2019, 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 employee stock purchase plan. At September 30, 2020, we had 3,321,597 shares of common stock reserved for future issuance under the ESPP. We issued 764,173 shares under this plan in the nine months ended September 30, 2020 and the weighted average purchase price was $32.67 per share. During the nine months ended September 30, 2020, 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. On January 21, 2004, our Board of Directors designated 750,000 of these shares as Series A Participating Preferred Stock in conjunction with the adoption of a Preferred Stock Rights Agreement which expired on May 10, 2014. There were no shares of preferred stock issued and outstanding at September 30, 2020. Stock repurchases and retirements

Segment and geographic informat

Segment and geographic information	9 Months Ended
	Sep. 30, 2020
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 in 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, similar product mix, similar customers, and similar distribution methods. 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).

Debt

Debt	9 Months Ended
	Sep. 30, 2020
Debt Disclosure [Abstract]
Debt	Debt On June 12, 2020, we entered into an Amended and Restated Credit Agreement (the “Credit Agreement”) with the lenders from time to time party thereto (the “Lenders"), and Wells Fargo Bank, National Association, as the administrative agent, swingline lender and issuing lender (“Administrative Agent”), with Wells Fargo Securities, LLC and BofA Securities, Inc., as joint lead arrangers and joint bookrunners. The Credit Agreement amends and restates in its entirety and refinances our previous loan agreement, dated as of May 9, 2013, with Wells Fargo Bank, National Association, which was amended on April 16, 2020 as well as on October 29, 2015 and April 27, 2018 (the “Loan Agreement”). The Credit Agreement was subsequently amended on October 30, 2020 as further described in Note 18 – Subsequent Events of Notes to Consolidated Financial Statements. The Credit Agreement provides for an initial $145 million credit facility consisting of a secured revolving loan facility in an aggregate principal amount of up to $75 million, including a $10 million sub-facility for the issuance of letters of credit, and a secured term loan facility in an aggregate principal amount of up to $70 million, which term loan facility is available until the date that is 60 days following the closing date of the Credit Agreement. Subject to the terms and conditions of the Credit Agreement, including obtaining commitments from existing lenders or new lenders, we may request additional term loan or revolving commitments of up to $105 million in the aggregate. Pursuant to the Credit Agreement, the revolving line of credit terminates, and all revolving loans and term loans are due and payable, on June 12, 2023. The revolving loans and term 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 1.25% to 1.75%, or LIBOR plus a margin of 2.25% to 2.75%, in each case with the margin being determined based upon our consolidated total leverage ratio. The term loan amortizes in quarterly payments equal to 1.25% of the original principal amount of the term loan, with the remaining outstanding balance being due and payable at maturity. The Credit Agreement contains financial covenants requiring us to maintain a maximum total leverage ratio of less than or equal to 2.75 to 1.00 and a minimum fixed charge coverage ratio of greater than or equal to 1.25 to 1.00, in each case determined in accordance with the Credit Agreement. The Credit Agreement provides for a commitment fee of 0.375% to 0.500% per annum, determined based upon our consolidated total leverage ratio, on the average daily unused amount of the revolving committed amount, payable quarterly in arrears. In addition, we will pay commitment fees based on the applicable margin set forth in the Credit Agreement in an amount equal to 0.375% to 0.500% per annum, determined based upon our consolidated total leverage ratio, of the initial term loan as a commitment fee until such time as the initial term loan is drawn or the initial term loan commitments expire or are terminated. The Credit Agreement requires that certain of the Company’s wholly-owned domestic subsidiaries (the “Subsidiary Guarantors”) will enter into a guaranty agreement (“Guaranty”) in favor of the Administrative Agent guarantying our obligations under the Credit Agreement, among other things. In connection with the Credit Agreement and Guaranty, we, along with the Subsidiary Guarantors and the Administrative Agent have entered into a Collateral Agreement (“Collateral Agreement”) pursuant to which we and each Subsidiary Guarantor have granted a lien on substantially all of our 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 our 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 loans made under the revolving loan facility portion 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, 2020 and December 31, 2019, respectively (unaudited, in thousands): September 30, December 31, 2020 2019 Secured 2020 term loan (effective interest rate of 3.0%) $ 69,125 $ — 2020 revolving loan facility (effective interest rate of 3.0%) 20,000 — Total Debt 89,125 — Less: Unamortized debt issuance costs (1,336) — Less: Current Portion of Total Debt (3,500) — Total Debt, non-current $ 84,289 $ —

Commitments and contingencies

Commitments and contingencies	9 Months Ended
	Sep. 30, 2020
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, 2020 and 2019 was as follows:  Nine Months Ended September 30, (In thousands) (Unaudited)  2020 2019 Balance at the beginning of the period $ 2,561 $ 3,173 Accruals for warranties issued during the period 1,824 1,665 Accruals related to pre-existing warranties 405 (441) Settlements made (in cash or in kind) during the period (2,088) (1,899) Balance at the end of the period $ 2,702 $ 2,498

Restructuring

Restructuring	9 Months Ended
	Sep. 30, 2020
Restructuring and Related Activities [Abstract]
Restructuring	Restructuring Since the first quarter of 2017, we have been taking steps to optimize our processes, reduce job duplication, evaluate where we should shift and centralize activities, improve efficiencies, and rebalance our resources on what we believe to be higher return activities. These steps involve reductions in our overall employee headcount. The timing and scope of our headcount reductions will vary. 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)  2020 2019 2020 2019 Cost of sales $ (13) — $ 7 — Research and development 38 34 4,716 690 Sales and marketing 512 2,993 8,055 7,958 General and administrative 121 990 683 2,512 Total restructuring and other related costs $ 658 4,017 $ 13,461 11,160 A summary of balance sheet activity related to our restructuring activity is shown below:  Restructuring Liability  (in thousands) Balance as of December 31, 2019 $ 9,527 Income statement expense 13,461 Cash payments (19,651) Balance as of September 30, 2020 $ 3,337 The liability of $3.3 million at September 30, 2020 relating to our restructuring activity is recorded in the “accrued compensation” line item of our consolidated balance sheet. ໿

Litigation

Litigation	9 Months Ended
	Sep. 30, 2020
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 will 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, 2020
Business Combinations [Abstract]
Acquisitions	Acquisitions Acquisition of OptimalPlus On July 2, 2020, we completed the acquisition of Optimal Plus 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 is being 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 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 nine months ended September 30, 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 preliminary purchase price allocation of OptimalPlus (in thousands): July 2, 2020 Consideration Transferred 352,642 Cash 17,661 Intangible assets 127,600 Goodwill 227,280 Contract assets 15,454 Deferred revenue (7,341) Accounts receivable 4,927 Other assets and liabilities (2,545) Deferred tax liabilities (30,394) Net assets acquired 352,642 Our preliminary estimates of the fair value of the assets acquired and the liabilities assumed are based on the information currently available, and we are continuing to evaluate the underlying inputs and assumptions used in our valuations. Accordingly, these preliminary estimates are subject to change during the measurement period, which is up to one year from the date of acquisition. A decrease in the fair value of assets acquired or an increase in the fair value of liabilities assumed in the acquisition from those valuation would result in a corresponding increase in the amount of goodwill acquired. Acquired intangible assets will be amortized over their estimated useful lives on a straight-line basis. The following table summarizes the preliminary purchase price allocation, and the preliminary 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 81,400 6 In-process research and development (IPR&D) 10,200 6 Other intangibles 5,900 3-5 Total 127,600 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. 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 stock 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 nine months ended September 30, 2019, 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 2019 2020 2019 (in thousands) (unaudited) (unaudited) Net sales $ 309,142 $ 348,401 $ 929,381 $ 1,009,102 Net income $ 4,907 $ 42,522 $ 123,766 $ 65,796

Subsequent events

Subsequent events	9 Months Ended
	Sep. 30, 2020
Subsequent Events [Abstract]
Subsequent events	Subsequent events Dividends On October 28, 2020, our Board of Directors declared a quarterly cash dividend of $0.26 per common share, payable on December 7, 2020, to stockholders of record on November 16, 2020. Credit Agreement On October 30, 2020, we amended our existing Credit Agreement to (i) increase the revolving line of credit from $75 million to $115 million, (ii) refinance the existing $70 million term loan with a new $100 million term loan, (iii) increase our ability to borrow additional funds by amending the incremental facilities limit to $100 million plus an unlimited amount, so long as after giving effect to the incurrence of such incremental increases, on a pro forma basis, the consolidated total leverage ratio does not exceed 2.25 to 1.00, (iv) reduce the applicable margin for LIBOR loans to a range of 1.50% to 2.00% and the applicable margin for base rate loans to a range of 0.50% to 1.00%, in each case based on our consolidated total leverage ratio, and remove the LIBOR floor, (v) amend the revolving credit commitment fee of 0.375% to 0.500% per annum to 0.250% to 0.375% per annum, determined based upon our consolidated total leverage ratio, on the average daily unused amount of the revolving committed amount, payable quarterly in arrears, (vi) extend the maturity date of both the revolving line of credit and term loan from June 12, 2023 to June 12, 2024 (the “Maturity Date”), and (vi) provide that the term loan shall be paid after the effective date for the Amendment in quarterly installments equal to 1.25% of the original principal amount and shall be paid in full, with accrued interest, on the Maturity Date. 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 Plan is expected to result in reductions to our worldwide headcount of approximately 9% over the next 9-12 months. In connection with the Plan, we currently estimate that we will incur pre-tax charges of approximately $22 million to $28 million, consisting primarily of cash termination benefits and other employee-related costs that will be paid over the next 9-12 months. We expect that the majority of these charges will be recognized during the fourth quarter of 2020.

Basis of presentation (Policies

Basis of presentation (Policies)	9 Months Ended
	Sep. 30, 2020
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Basis of Accounting, Policy	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, 2019, included in our Annual Report on Form 10-K filed with the Securities and Exchange Commission ("SEC") on February 20, 2020 (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, 2020 and December 31, 2019, the results of our operations and comprehensive income for three and nine months ended September 30, 2020 and 2019, our cash flows for the nine months ended September 30, 2020 and 2019 and our statement of stockholders' equity for the three and nine months ended September 30, 2020 and 2019. Our operating results for the three and nine months ended September 30, 2020 are not necessarily indicative of the results that may be expected for the year ending December 31, 2020. These financial statements have been prepared in accordance with accounting principles generally accepted in the United States. Reclassifications As further discussed below, certain prior period amounts have been reclassified to conform to the current period presentation. The reclassifications had no impact on our previously reported net income or cash flows: • Before the second quarter of 2020, we included net sales attributable to our operations in India within the EMEIA region in Note 2 - Revenue of Notes to Consolidated Financial Statements. In the second quarter of 2020, we began including these amounts within the APAC (Australia, India, New Zealand, Southeast Asia, China, South Korea and Japan) geographic region, to reflect recent changes within our organizational structure. We have recast historical comparative information to conform to the September 30, 2020 presentation. Refer to Note 2 - Revenue of Notes to Consolidated Financial Statements for our revenue disaggregated by geographic region which now include the Americas (United States, Canada and Latin America), EMEA (Europe, Middle East, and Africa) and APAC. • Before the second quarter of 2020, we presented “Interest income”, "Net foreign exchange gain (loss)", and "Other income (loss)" separately on the consolidated statements of income. In the second quarter of 2020, we began presenting these amounts within “Other (expense) income” in the consolidated statements of income for all periods presented. Refer to "Other (expense) income" in Note 1 - Basis of Presentation of Notes to Consolidated Financial Statements for additional information on the amounts that comprise "Other (expense) income". Disclosures about Acquired and Disposed Businesses In May 2020, the SEC adopted Release No. 33-10786 "Amendments to Financial Disclosures about Acquired and Disposed Businesses" ("Release No. 33-10786") which includes amendments to certain of its rules and forms related to the disclosure of financial information regarding acquired or disposed businesses. Among other changes, the amendments impact SEC rules relating to (1) the definition of “significant” subsidiaries, (2) requirements to provide financial statements for “significant” acquisitions, and (3) revisions to the formulation and usage of pro forma financial information. Release No. 33-10786 is effective on January 1, 2021, however, voluntary early adoption is permitted as long as all amendments are adopted in their entirety. We elected to early adopt all provisions of Release No. 33-10786 during the second quarter of 2020. Summary of Significant Accounting Policies As discussed above, we adopted the new expected credit loss standard as of January 1, 2020. There were no other significant changes in our accounting policies during the three and nine months ended September 30, 2020 compared to the significant accounting policies described in our Form 10-K.
Other Recently Adopted Accounting Pronouncements and Recent Accounting Guidance Not Yet Adopted	Recently Adopted Accounting Pronouncements Current Expected Credit Losses ("CECL") In June 2016, the Financial Accounting Standards Board ("FASB") issued ASU No. 2016-13, "Financial Instruments—Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments." The ASU replaces the incurred-loss impairment methodology and requires immediate recognition of estimated credit losses expected to occur for most financial assets, including trade receivables. Credit losses on available-for-sale debt securities with unrealized losses will be recognized as allowances for credit losses limited to the amount by which fair value is below amortized cost. We adopted the new standard on January 1, 2020 and the impact of the adoption was not material to our consolidated financial statements as credit losses are not expected to be significant based on historical collection trends, the financial condition of payment partners, and external market factors. We will continue to actively monitor the impact of the recent coronavirus (COVID-19) pandemic on expected credit losses.
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.
Software to be Sold, Leased, or Otherwise Marketed, Policy	Implementation Costs Incurred in a Cloud Computing Arrangement In August 2018, the FASB issued ASU 2018-15, “Customer’s Accounting for Implementation Costs Incurred in a Cloud Computing Arrangement That Is a Service Contract,” which clarifies the accounting for implementation costs in cloud computing arrangements. The new standard aligns the treatment of implementation costs incurred by customers in cloud computing arrangements that are service contracts with the treatment of similar costs incurred to develop or obtain internal-use software. Under the new standard, implementation costs are deferred and presented in the same financial statement caption on the condensed consolidated balance sheet as a prepayment of related arrangement fees. The deferred costs are recognized over the term of the arrangement in the same financial statement caption in the condensed consolidated income statement as the related fees of the arrangement. We adopted the new standard on January 1, 2020. The new standard did not have a material impact on our consolidated financial statements and related disclosures.
Fair Value Measurement, Policy	Fair Value Measurements In August 2018, the FASB issued ASU 2018-13, “Disclosure Framework — Changes to the Disclosure Requirements for Fair Value Measurement,” which modifies the disclosure requirements on fair value measurements. We adopted the new standard on January 1, 2020. The new standard did not have a material impact on our consolidated financial statements and related disclosures.
Income Tax, Policy	Income Taxes In December 2019, the FASB issued ASU 2019-12, “Income Taxes — Simplifying the Accounting for Income Taxes (Topic 740),” which simplifies the accounting for income taxes by removing certain exceptions to the general principles in Topic 740. The amendments in this ASU also improve consistency and simplify other areas of Topic 740 by clarifying and amending existing guidance. The amendments in this ASU will be applied using different approaches depending on what the specific amendment relates to and, for public entities, are effective for fiscal years, and interim periods within those fiscal years, beginning after December 15, 2020. An entity is permitted to early adopt the guidance, and we early adopted ASU 2019-12 as of January 1, 2020. The adoption did not have a material impact on our consolidated financial statements and related disclosures.
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. Before the second quarter of 2020, we included net sales attributable to our operations in India within the EMEIA region. In the second quarter of 2020, we began including these amounts within the APAC geographic region, to reflect recent changes within our organizational structure. We have recast historical comparative information to conform to the September 30, 2020 presentation. The geographic regions are now presented as the Americas, EMEA and APAC to reflect this change. 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.

Basis of presentation (Tables)

Basis of presentation (Tables)	9 Months Ended
	Sep. 30, 2020
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Disposal Groups, Including Discontinued Operations	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) Income Other (expense) income, net consisted of the following amounts (in thousands): Three Months Ended September 30, Nine Months Ended September 30, (Unaudited) (Unaudited) 2020 2019 2020 2019 Interest income $ 414 $ 1,930 $ 3,724 $ 6,187 Interest expense (973) — (1,115) — Loss from equity-method investments (627) (239) (2,559) (406) Net foreign exchange loss (676) (378) (2,019) (1,623) Other (139) 936 (615) 1,221 Other (expense) income, net $ (2,001) $ 2,249 $ (2,584) $ 5,379
Reconciliation Of The Denominators Used To Calculate Basic EPS 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, 2020 and 2019, are as follows (in thousands):  Three Months Ended September 30, Nine Months Ended September 30,  (Unaudited) (Unaudited)  2020 2019 2020 2019 Weighted average shares outstanding-basic 131,419 131,385 131,017 131,896 Plus: Common share equivalents RSUs — 504 654 994 Weighted average shares outstanding-diluted 131,419 131,889 131,671 132,890
Other Current Liabilities	Other current liabilities on our consolidated balance sheet includes the following amounts (in thousands): As of September 30, 2020 As of December 31, (unaudited) 2019 Income taxes payable - current $ 23,487 $ 6,791 Other 26,772 13,925 Total $ 50,259 $ 20,716

Revenue (Tables)

Revenue (Tables)	9 Months Ended
	Sep. 30, 2020
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)  2020 2019 Net sales: Point-in-Time (1) Over Time Total Point-in-Time (1) Over Time Total Americas $ 107,808 $ 19,241 $ 127,049 $ 119,895 $ 23,222 $ 143,117 EMEA 57,988 20,551 78,539 70,076 19,662 89,738 APAC 92,050 10,486 102,536 98,161 9,426 107,587 Total net sales (1) $ 257,846 $ 50,278 $ 308,124 $ 288,132 $ 52,310 $ 340,442 (1) Net sales contains hedging gains and losses, which do not represent revenues recognized from customers.  Nine Months Ended September 30, (In thousands) (Unaudited)  2020 2019 Net sales: Point-in-Time (1) Over Time Total Point-in-Time (1) Over Time Total Americas $ 316,220 $ 57,554 $ 373,774 $ 325,349 $ 69,337 $ 394,686 EMEA 181,330 58,594 239,924 216,644 57,411 274,055 APAC 274,341 30,795 305,136 290,140 26,866 317,006 Total net sales (1) $ 771,891 $ 146,943 $ 918,834 $ 832,133 $ 153,614 $ 985,747 (1) Net sales contains hedging gains and losses, which do not represent revenues recognized from customers.
Schedule of Changes in Deferred Revenue, Current and Non-Current	Changes in deferred revenue, current and non-current, during the nine months ended September 30, 2020 were as follows:  Amount  (In thousands) Balance as of December 31, 2019 $ 164,925 Deferral of revenue billed in current period, net of recognition 95,934 Recognition of revenue deferred in prior periods (103,274) Acquisitions/Divestitures (7,955) Foreign currency translation impact 1,451 Balance as of September 30, 2020 (unaudited) $ 151,081

Short-term investments (Tables)

Short-term investments (Tables)	9 Months Ended
	Sep. 30, 2020
Cash, Cash Equivalents, and Short-term Investments [Abstract]
Schedule of Available-for-sale Securities Reconciliation	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, 2020 (In thousands) (Unaudited)  Gross Gross  Adjusted Cost Unrealized Gain Unrealized Loss Fair Value Corporate bonds $ 92,610 $ 245 $ (2) $ 92,853 Total Short-term investments $ 92,610 $ 245 $ (2) $ 92,853 (In thousands) As of December 31, 2019  Gross Gross  Adjusted Cost Unrealized Gain Unrealized Loss Fair Value Corporate bonds $ 237,423 $ 628 $ (68) $ 237,983 Total Short-term investments $ 237,423 $ 628 $ (68) $ 237,983
Investments Classified by Contractual Maturity Date	The following tables summarize the contractual maturities of our short-term investments designated as available-for-sale debt securities:  As of September 30, 2020 (In thousands) (Unaudited)  Adjusted Cost Fair Value Due in less than 1 year $ 88,194 $ 88,438 Due in 1 to 5 years 4,416 4,415 Total available-for-sale debt securities $ 92,610 $ 92,853  Due in less than 1 year Adjusted Cost Fair Value Corporate bonds $ 88,194 $ 88,438 Total available-for-sale debt securities $ 88,194 $ 88,438  Due in 1 to 5 years Adjusted Cost Fair Value Corporate bonds $ 4,416 $ 4,415 Total available-for-sale debt securities $ 4,416 $ 4,415

Fair value measurements (Tables

Fair value measurements (Tables)	9 Months Ended
	Sep. 30, 2020
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, 2020 Quoted Prices in Active Markets for Identical Assets (Level 1) Significant Other Observable Inputs (Level 2) Significant Unobservable Inputs (Level 3) Assets Cash and cash equivalents available for sale: Money Market Funds $ 82,730 $ 82,730 $ — $ — Short-term investments available for sale: Corporate notes and bonds 92,853 — 92,853 — Derivatives 5,363 — 5,363 — Total Assets $ 180,946 $ 82,730 $ 98,216 $ —  Liabilities Derivatives $ (10,777) $ — $ (10,777) $ — Total Liabilities $ (10,777) $ — $ (10,777) $ — (In thousands) Fair Value Measurements at Reporting Date Using Description December 31, 2019 Quoted Prices in Active Markets for Identical Assets (Level 1) Significant Other Observable Inputs (Level 2) Significant Unobservable Inputs (Level 3) Assets Cash and cash equivalents available for sale: Money Market Funds $ 87,397 $ 87,397 $ — $ — Corporate notes and bonds 9,962 — 9,962 — Short-term investments available for sale: Corporate bonds 237,983 — 237,983 — Derivatives 8,209 — 8,209 — Total Assets $ 343,551 $ 87,397 $ 256,154 $ —  Liabilities Derivatives $ (2,872) $ — $ (2,872) $ — Total Liabilities $ (2,872) $ — $ (2,872) $ —

Derivative instruments and he_2

Derivative instruments and hedging activities (Tables)	9 Months Ended
	Sep. 30, 2020
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Summary of Notional Amounts of Derivative Instruments	We held forward contracts designated as cash flow hedges with the following notional amounts: (In thousands) US Dollar Equivalent  As of September 30, 2020 As of December 31,  (Unaudited) 2019 British pound $ 23,251 $ 13,988 Chinese yuan 57,943 32,970 Euro 209,385 130,122 Hungarian forint 89,962 95,228 Japanese yen 83,503 53,527 Korean won 26,918 24,728 Malaysian ringgit 41,681 32,725 Total forward contracts notional amount $ 532,643 $ 383,288
Summary of Fair Value of Derivative Instruments on Consolidated Balance Sheets	The following tables present the fair value of derivative instruments on our Consolidated Balance Sheets at September 30, 2020 and December 31, 2019, respectively.  Asset Derivatives  September 30, 2020 December 31, 2019 (In thousands) (Unaudited)  Balance Sheet Location Fair Value Balance Sheet Location Fair Value Derivatives designated as hedging instruments Foreign exchange contracts - ST forwards Prepaid expenses and other current assets $ 2,314 Prepaid expenses and other current assets $ 7,039 Foreign exchange contracts - LT forwards Other long-term assets 2,639 Other long-term assets 970 Total derivatives designated as hedging instruments $ 4,953 $ 8,009 Derivatives not designated as hedging instruments Foreign exchange contracts - ST forwards Prepaid expenses and other current assets $ 411 Prepaid expenses and other current assets $ 200 Total derivatives not designated as hedging instruments $ 411 $ 200 Total derivatives $ 5,364 $ 8,209  Liability Derivatives  September 30, 2020 December 31, 2019 (In thousands) (Unaudited)  Balance Sheet Location Fair Value Balance Sheet Location Fair Value Derivatives designated as hedging instruments Foreign exchange contracts - ST forwards Other current liabilities $ (5,305) Other current liabilities $ (2,089)  Foreign exchange contracts - LT forwards Other long-term liabilities (4,230) Other long-term liabilities (351) Total derivatives designated as hedging instruments $ (9,535) $ (2,440)  Derivatives not designated as hedging instruments  Foreign exchange contracts - ST forwards Other current liabilities $ (1,241) Other current liabilities $ (432) Total derivatives not designated as hedging instruments $ (1,241) $ (432)  Total derivatives $ (10,776) $ (2,872)
Summary of Derivative Instruments, Gain (Loss)	The following tables present the effect of derivative instruments on our Consolidated Statements of Income for the three months ended September 30, 2020 and 2019, respectively: 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 1,144 Operating expenses (266) Total $ (9,531) $ (380) September 30, 2019 (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 $ 6,736 Net sales $ 3,291  Foreign exchange contracts - forwards (2,946) Cost of sales (176)  Foreign exchange contracts - forwards (2,163) Operating expenses (112) Total $ 1,627 $ 3,003 (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, 2020 September 30, 2019  (Unaudited) (Unaudited) Foreign exchange contracts - forwards Other expense (income) $ (267) 287  Total $ (267) $ 287 The following tables present the effect of derivative instruments on our Consolidated Statements of Income for the nine months ended September 30, 2020 and 2019, respectively: 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 September 30, 2019 (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 $ 7,186 Net sales $ 7,687  Foreign exchange contracts - forwards (3,386) Cost of sales (217)  Foreign exchange contracts - forwards (2,441) Operating expenses (158) Total $ 1,359 $ 7,312 (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, 2020 September 30, 2019  (Unaudited) (Unaudited) Foreign exchange contracts - forwards Other income (expense) $ (163) (82) Total $ (163) $ (82)

Inventories, net (Tables)

Inventories, net (Tables)	9 Months Ended
	Sep. 30, 2020
Inventory Disclosure [Abstract]
Schedule of Inventory	Inventories, net consist of the following:  September 30, 2020 December 31, (In thousands) (Unaudited) 2019  Raw materials $ 110,773 $ 110,078 Work-in-process 12,235 10,613 Finished goods 86,550 79,719 Total $ 209,558 $ 200,410

Intangible assets and goodwil_2

Intangible assets and goodwill, net (Tables)	9 Months Ended
	Sep. 30, 2020
Goodwill and Intangible Assets Disclosure [Abstract]
Schedule of Finite-Lived Intangible Assets	Intangible assets at September 30, 2020 and December 31, 2019 are as follows:  September 30, 2020 (In thousands) (Unaudited) December 31, 2019  Gross Carrying Amount Accumulated Amortization Net Carrying Amount Gross Carrying Amount Accumulated Amortization Net Carrying Amount Capitalized software development costs $ 123,483 $ (86,096) $ 37,387 $ 132,789 $ (76,910) $ 55,879 Acquired technology 105,008 (14,726) 90,282 91,900 (87,917) 3,983 Patents 36,531 (26,008) 10,523 35,609 (23,993) 11,616 Other 74,671 (29,796) 44,875 44,490 (31,885) 12,605 Total $ 339,693 $ (156,626) $ 183,067 $ 304,788 $ (220,705) $ 84,083
Schedule of Goodwill	The carrying amount of goodwill as of September 30, 2020, was as follows:  Amount  (In thousands) Balance as of December 31, 2019 $ 262,242 Acquisition 227,280 Foreign currency translation impact 4,800 Divestiture (7,221) Balance as of September 30, 2020 (unaudited) $ 487,101

Leases (Tables)

Leases (Tables)	9 Months Ended
	Sep. 30, 2020
Leases [Abstract]
Lease, Cost	The components of operating lease expense were as follows (unaudited): Three Months Ended Nine Months Ended (In thousands) September 30, 2020 September 30, 2019 September 30, 2020 September 30, 2019 Operating Lease Cost (a) $ 4,869 $ 5,456 $ 15,941 $ 16,951 (a) includes variable and short-term lease costs
Lessee, Operating Lease, Liability, Maturity	Maturities of lease liabilities as of September 30, 2020 were as follows (unaudited): (In thousands) Years ending December 31, Operating Leases 2020 (Excluding the nine months ended September 30, 2020) $ 7,012 2021 17,340 2022 11,465 2023 8,229 2024 7,062 Thereafter 14,161 Total future minimum lease payments 65,269 Less imputed interest (11,325) Total $ 53,944

Comprehensive income (Tables)

Comprehensive income (Tables)	9 Months Ended
	Sep. 30, 2020
Accumulated Other Comprehensive Income (Loss), Net of Tax [Abstract]
Summary of Comprehensive Income (Loss)	The accumulated OCI, net of tax, for the nine months ended September 30, 2020 and 2019, consisted of the following:  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) expense — (45) (2,223) (2,268) Balance as of September 30, 2020 $ (19,324) $ (357) $ (3,059) $ (22,740)  September 30, 2019  (Unaudited) (In thousands) Currency translation adjustment Investments Derivative instruments Accumulated other comprehensive income/(loss) Balance as of December 31, 2018 $ (22,485) $ (1,308) 6,862 $ (16,931) Current-period other comprehensive (loss) income (9,303) 1,494 8,671 862 Reclassified from accumulated OCI into income — — (7,312) (7,312) Income tax (benefit) expense — (11) 366 355 Balance as of September 30, 2019 $ (31,788) $ 197 $ 7,855 $ (23,736)

Authorized shares of common a_2

Authorized shares of common and preferred stock and stock-based compensation plans (Tables)	9 Months Ended
	Sep. 30, 2020
Share-based Payment Arrangement [Abstract]
Share-based Payment Arrangement, Performance Shares, Activity	The key assumptions used in valuing these market-based awards are as follows: Nine Months Ended (unaudited) September 30, 2020 September 30, 2019 Number of simulations 100,000 100,000 Expected volatility 27.41% 26.08% Expected life in years 2.92 years 2.94 years Risk-free interest rate 1.38% 2.52% Dividend yield 2.32% 1.96%

Debt (Tables)

Debt (Tables)	9 Months Ended
	Sep. 30, 2020
Debt Disclosure [Abstract]
Schedule of Long-term Debt Instruments	The following table presents the amounts outstanding related to our borrowing arrangements discussed above as of September 30, 2020 and December 31, 2019, respectively (unaudited, in thousands): September 30, December 31, 2020 2019 Secured 2020 term loan (effective interest rate of 3.0%) $ 69,125 $ — 2020 revolving loan facility (effective interest rate of 3.0%) 20,000 — Total Debt 89,125 — Less: Unamortized debt issuance costs (1,336) — Less: Current Portion of Total Debt (3,500) — Total Debt, non-current $ 84,289 $ —

Commitments and contingencies (

Commitments and contingencies (Tables)	9 Months Ended
	Sep. 30, 2020
Commitments and Contingencies Disclosure [Abstract]
Schedule of Product Warranty Liability	The warranty reserve for the nine months ended September 30, 2020 and 2019 was as follows:  Nine Months Ended September 30, (In thousands) (Unaudited)  2020 2019 Balance at the beginning of the period $ 2,561 $ 3,173 Accruals for warranties issued during the period 1,824 1,665 Accruals related to pre-existing warranties 405 (441) Settlements made (in cash or in kind) during the period (2,088) (1,899) Balance at the end of the period $ 2,702 $ 2,498

Restructuring (Tables)

Restructuring (Tables)	9 Months Ended
	Sep. 30, 2020
Restructuring and Related Activities [Abstract]
Summary of Restructuring Related Costs	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)  2020 2019 2020 2019 Cost of sales $ (13) — $ 7 — Research and development 38 34 4,716 690 Sales and marketing 512 2,993 8,055 7,958 General and administrative 121 990 683 2,512 Total restructuring and other related costs $ 658 4,017 $ 13,461 11,160
Schedule of Restructuring Reserve	A summary of balance sheet activity related to our restructuring activity is shown below:  Restructuring Liability  (in thousands) Balance as of December 31, 2019 $ 9,527 Income statement expense 13,461 Cash payments (19,651) Balance as of September 30, 2020 $ 3,337

Acquisitions (Tables)

Acquisitions (Tables)	9 Months Ended
	Sep. 30, 2020
Business Combinations [Abstract]
Schedule of Recognized Identified Assets Acquired and Liabilities Assumed	The information below represents the preliminary purchase price allocation of OptimalPlus (in thousands): July 2, 2020 Consideration Transferred 352,642 Cash 17,661 Intangible assets 127,600 Goodwill 227,280 Contract assets 15,454 Deferred revenue (7,341) Accounts receivable 4,927 Other assets and liabilities (2,545) Deferred tax liabilities (30,394) Net assets acquired 352,642
Finite-Lived and Indefinite-Lived Intangible Assets Acquired as Part of Business Combination	The following table summarizes the preliminary purchase price allocation, and the preliminary 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 81,400 6 In-process research and development (IPR&D) 10,200 6 Other intangibles 5,900 3-5 Total 127,600
Business Acquisition, Pro Forma Information	Three Months Ended September 30, Nine Months Ended September 30, 2020 2019 2020 2019 (in thousands) (unaudited) (unaudited) Net sales $ 309,142 $ 348,401 $ 929,381 $ 1,009,102 Net income $ 4,907 $ 42,522 $ 123,766 $ 65,796

Basis of presentation - Narrati

Basis of presentation - Narrative (Details) - USD ($) $ in Thousands	Jan. 15, 2020	Sep. 30, 2020	Sep. 30, 2019
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Disposal gain on sale of business/asset		$ 159,753	$ 26,842
Business acquisition, transaction costs	$ 1,000
AWR Corporation | Disposal Group, Disposed of by Sale, Not Discontinued Operations
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Proceeds from sale of business	161,000
Disposal gain on sale of business/asset	$ 160,000

Basis of Presentation - Disposa

Basis of Presentation - Disposal Groups, Including Discontinued Operations (Details) - Disposal Group, Disposed of by Sale, Not Discontinued Operations - 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 - Schedul

Basis of presentation - Schedule of Other Income (Expense) (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Interest income	$ 414	$ 1,930	$ 3,724	$ 6,187
Interest expense	(973)	0	(1,115)	0
Loss from equity-method investments	(627)	(239)	(2,559)	(406)
Net foreign exchange loss	(676)	(378)	(2,019)	(1,623)
Other	(139)	936	(615)	1,221
Other (expense) income	$ (2,001)	$ 2,249	$ (2,584)	$ 5,379

Basis of presentation - Sched_2

Basis of presentation - Schedule of Earnings Per Share (Details) - shares	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Weighted average shares outstanding - basic (in shares)	131,419,000	131,385,000	131,017,000	131,896,000
Plus: Common share equivalents
RSUs (in shares)	0	504,000	654,000	994,000
Weighted average shares outstanding-diluted (in shares)	131,419,000	131,889,000	131,671,000	132,890,000
Anti-dilutive securities excluded from the computation of diluted EPS (in shares)	3,490,700	1,611,000	276,000	568,000

Basis of presentation - Sched_3

Basis of presentation - Schedule of Other Current Liabilities (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Income taxes payable - current	$ 23,487	$ 6,791
Other	26,772	13,925
Other current liabilities	$ 50,259	$ 20,716

Revenue - Disaggregation of Rev

Revenue - Disaggregation of Revenue (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Disaggregation of Revenue [Line Items]
Total net sales	$ 308,124	$ 340,442	$ 918,834	$ 985,747
Point-in-Time(1)
Disaggregation of Revenue [Line Items]
Total net sales	257,846	288,132	771,891	832,133
Over Time
Disaggregation of Revenue [Line Items]
Total net sales	50,278	52,310	146,943	153,614
Americas
Disaggregation of Revenue [Line Items]
Total net sales	127,049	143,117	373,774	394,686
Americas | Point-in-Time(1)
Disaggregation of Revenue [Line Items]
Total net sales	107,808	119,895	316,220	325,349
Americas | Over Time
Disaggregation of Revenue [Line Items]
Total net sales	19,241	23,222	57,554	69,337
EMEA
Disaggregation of Revenue [Line Items]
Total net sales	78,539	89,738	239,924	274,055
EMEA | Point-in-Time(1)
Disaggregation of Revenue [Line Items]
Total net sales	57,988	70,076	181,330	216,644
EMEA | Over Time
Disaggregation of Revenue [Line Items]
Total net sales	20,551	19,662	58,594	57,411
APAC
Disaggregation of Revenue [Line Items]
Total net sales	102,536	107,587	305,136	317,006
APAC | Point-in-Time(1)
Disaggregation of Revenue [Line Items]
Total net sales	92,050	98,161	274,341	290,140
APAC | Over Time
Disaggregation of Revenue [Line Items]
Total net sales	$ 10,486	$ 9,426	$ 30,795	$ 26,866

Revenue - Change in Deferred Re

Revenue - Change in Deferred Revenue (Details) $ in Thousands	9 Months Ended
	Sep. 30, 2020USD ($)
Movement in Deferred Revenue [Roll Forward]
Deferred revenue at December 31, 2018	$ 164,925
Deferral of revenue billed in current period, net of recognition	95,934
Recognition of revenue deferred in prior periods	(103,274)
Acquisitions/Divestitures	(7,955)
Foreign currency translation impact	1,451
Deferred revenue as of September 30, 2020	$ 151,081

Revenue - Performance Obligatio

Revenue - Performance Obligations (Details) $ in Thousands	Sep. 30, 2020USD ($)
Revenue from Contract with Customer [Abstract]
Revenue, remaining performance obligation	$ 84,000
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date: 2020-10-01
Revenue from Contract with Customer [Abstract]
Revenue, remaining performance obligation, percentage	15.00%
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, remaining performance obligation, period	3 months
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date: 2021-01-01
Revenue from Contract with Customer [Abstract]
Revenue, remaining performance obligation, percentage	43.00%
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, remaining performance obligation, period	1 year
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date: 2022-01-01
Revenue from Contract with Customer [Abstract]
Revenue, remaining performance obligation, percentage	42.00%
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, remaining performance obligation, period

Short-term investments - Unreal

Short-term investments - Unrealized Gains And Losses Related To Cash, Cash Equivalents, And Short-Term Investments Designated As Available-For-Sale (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Debt Securities, Available-for-sale [Line Items]
Adjusted Cost	$ 92,610	$ 237,423
Gross Unrealized Gain	245	628
Gross Unrealized Loss	(2)	(68)
Fair Value	92,853	237,983
Corporate bonds
Debt Securities, Available-for-sale [Line Items]
Adjusted Cost	92,610	237,423
Gross Unrealized Gain	245	628
Gross Unrealized Loss	(2)	(68)
Fair Value	$ 92,853	$ 237,983

Short-term investments - Contra

Short-term investments - Contractual Maturities Of Short-Term Investments Designated As Available-For-Sale (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Debt Securities, Available-for-sale [Line Items]
Adjusted Cost, Due in less than 1 year	$ 88,194
Fair Value, Due in less than 1 year	88,438
Adjusted Cost, Due in 1 to 5 years	4,416
Fair Value, Due in 1 to 5 years	4,415
Adjusted Cost	92,610	$ 237,423
Fair Value	92,853	237,983
Carrying value of equity method investments	20,000
Corporate bonds
Debt Securities, Available-for-sale [Line Items]
Adjusted Cost, Due in less than 1 year	88,194
Fair Value, Due in less than 1 year	88,438
Adjusted Cost, Due in 1 to 5 years	4,416
Fair Value, Due in 1 to 5 years	4,415
Fair Value	$ 92,853	$ 237,983

Fair value measurements - Sched

Fair value measurements - Schedule of Assets And Liabilities Measured On Recurring Basis (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Short-term investments available for sale:
Short-term investments available for sale	$ 92,853	$ 237,983
Derivatives	5,363	8,209
Total Assets	180,946	343,551
Derivatives	(10,777)	(2,872)
Total Liabilities	(10,777)	(2,872)
Short-term investments	$ 92,853	237,983
Available-for-sale contractual maturity (in months)	60 months
Europe
Short-term investments available for sale:
Short-term investments	$ 5,000
Quoted Prices in Active Markets for Identical Assets (Level 1)
Short-term investments available for sale:
Derivatives	0	0
Total Assets	82,730	87,397
Derivatives	0	0
Total Liabilities	0	0
Significant Other Observable Inputs (Level 2)
Short-term investments available for sale:
Derivatives	5,363	8,209
Total Assets	98,216	256,154
Derivatives	(10,777)	(2,872)
Total Liabilities	(10,777)	(2,872)
Significant Unobservable Inputs (Level 3)
Short-term investments available for sale:
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 available for sale	82,730	87,397
Money Market Funds | Quoted Prices in Active Markets for Identical Assets (Level 1)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and cash equivalents available for sale	82,730	87,397
Money Market Funds | Significant Other Observable Inputs (Level 2)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and cash equivalents available for sale	0	0
Money Market Funds | Significant Unobservable Inputs (Level 3)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and cash equivalents available for sale	0	0
Corporate bonds
Short-term investments available for sale:
Short-term investments available for sale	92,853	237,983
Corporate bonds | Quoted Prices in Active Markets for Identical Assets (Level 1)
Short-term investments available for sale:
Short-term investments available for sale	0	0
Corporate bonds | Significant Other Observable Inputs (Level 2)
Short-term investments available for sale:
Short-term investments available for sale	92,853	237,983
Corporate bonds | Significant Unobservable Inputs (Level 3)
Short-term investments available for sale:
Short-term investments available for sale	$ 0	0
U.S. treasuries and agencies
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and cash equivalents available for sale		9,962
U.S. treasuries and agencies | Quoted Prices in Active Markets for Identical Assets (Level 1)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and cash equivalents available for sale		0
U.S. treasuries and agencies | Significant Other Observable Inputs (Level 2)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and cash equivalents available for sale		9,962
U.S. treasuries and agencies | Significant Unobservable Inputs (Level 3)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and cash equivalents available for sale		$ 0

Derivative instruments and he_3

Derivative instruments and hedging activities - Narrative (Details)	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2020USD ($)country	Sep. 30, 2019	Sep. 30, 2020USD ($)country	Sep. 30, 2019	Dec. 31, 2019USD ($)
Derivative [Line Items]
Number of countries for which entity has operations | country	45		45
Percentage of sales outside of the Americas during the period	59.00%	58.00%	59.00%	60.00%
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
Derivatives, contractual maturities (in months)			36 months		36 months
Foreign currency forward contracts notional amount	$ 532,643,000		$ 532,643,000		$ 383,288,000
Cost of Sales
Derivative [Line Items]
Gains (losses) expected to be reclassified from AOCI to earnings			(1,000,000)
Forward Contracts | Net Sales
Derivative [Line Items]
Gains (losses) expected to be reclassified from AOCI to earnings			(600,000)
Forward Contracts | Operating Expenses
Derivative [Line Items]
Gains (losses) expected to be reclassified from AOCI to earnings			(1,400,000)
Other Derivatives
Derivative [Line Items]
Foreign currency forward contracts notional amount	$ 87,000,000		$ 87,000,000		$ 41,000,000
Maximum | Forward Contracts
Derivative [Line Items]
Percentage of derivative risk hedged	100.00%		100.00%
Duration of derivative contracts entered into by the entity to hedge risk of loss			40 months
Maximum | Other Derivatives
Derivative [Line Items]
Percentage of derivative risk hedged	90.00%		90.00%
Duration of derivative contracts entered into by the entity to hedge risk of loss			90 days

Derivative instruments and he_4

Derivative instruments and hedging activities - Summary Of Notional Amounts Of Derivative Instruments (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Derivative [Line Items]
Total forward contracts notional amount	$ 532,643	$ 383,288
British pound
Derivative [Line Items]
Total forward contracts notional amount	23,251	13,988
Chinese yuan
Derivative [Line Items]
Total forward contracts notional amount	57,943	32,970
Euro
Derivative [Line Items]
Total forward contracts notional amount	209,385	130,122
Hungarian forint
Derivative [Line Items]
Total forward contracts notional amount	89,962	95,228
Japanese yen
Derivative [Line Items]
Total forward contracts notional amount	83,503	53,527
Korean won
Derivative [Line Items]
Total forward contracts notional amount	26,918	24,728
Malaysian ringgit
Derivative [Line Items]
Total forward contracts notional amount	$ 41,681	$ 32,725

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, 2020	Dec. 31, 2019
Derivatives, Fair Value [Line Items]
Derivative assets	$ 5,364	$ 8,209
Derivative liability	(10,776)	(2,872)
Derivatives Designated As Hedging Instruments
Derivatives, Fair Value [Line Items]
Derivative assets	4,953	8,009
Derivative liability	(9,535)	(2,440)
Derivatives Designated As Hedging Instruments | Foreign Exchange Contract - Short-Term | Prepaid expenses and other current assets
Derivatives, Fair Value [Line Items]
Derivative assets	2,314	7,039
Derivatives Designated As Hedging Instruments | Foreign Exchange Contract - Short-Term | Other current liabilities
Derivatives, Fair Value [Line Items]
Derivative liability	(5,305)	(2,089)
Derivatives Designated As Hedging Instruments | Foreign Exchange Contracts - Long-Term | Other long-term assets
Derivatives, Fair Value [Line Items]
Derivative assets	2,639	970
Derivatives Designated As Hedging Instruments | Foreign Exchange Contracts - Long-Term | Other long-term liabilities
Derivatives, Fair Value [Line Items]
Derivative liability	(4,230)	(351)
Derivatives Not Designated As Hedging Instruments
Derivatives, Fair Value [Line Items]
Derivative assets	411	200
Derivative liability	(1,241)	(432)
Derivatives Not Designated As Hedging Instruments | Foreign Exchange Contract - Short-Term | Prepaid expenses and other current assets
Derivatives, Fair Value [Line Items]
Derivative assets	411	200
Derivatives Not Designated As Hedging Instruments | Foreign Exchange Contract - Short-Term | Other current liabilities
Derivatives, Fair Value [Line Items]
Derivative liability	$ (1,241)	$ (432)

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, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Derivatives Designated As Hedging Instruments
Derivative Instruments, Gain (Loss) [Line Items]
Gain or (Loss) Recognized in OCI on Derivative	$ (9,531)	$ 1,627	$ (10,128)	$ 1,359
Gain or (Loss) Reclassified from Accumulated OCI into Income	(380)	3,003	2,429	7,312
Derivatives Designated As Hedging Instruments | Foreign Exchange Forward | Net Sales
Derivative Instruments, Gain (Loss) [Line Items]
Gain or (Loss) Recognized in OCI on Derivative	(12,524)	6,736	(6,800)	7,186
Gain or (Loss) Reclassified from Accumulated OCI into Income	334	3,291	5,594	7,687
Derivatives Designated As Hedging Instruments | Foreign Exchange Forward | Cost of Sales
Derivative Instruments, Gain (Loss) [Line Items]
Gain or (Loss) Recognized in OCI on Derivative	1,849	(2,946)	(1,898)	(3,386)
Gain or (Loss) Reclassified from Accumulated OCI into Income	(448)	(176)	(1,817)	(217)
Derivatives Designated As Hedging Instruments | Foreign Exchange Forward | Operating Expenses
Derivative Instruments, Gain (Loss) [Line Items]
Gain or (Loss) Recognized in OCI on Derivative	1,144	(2,163)	(1,430)	(2,441)
Gain or (Loss) Reclassified from Accumulated OCI into Income	(266)	(112)	(1,348)	(158)
Derivatives Not Designated As Hedging Instruments
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain (Loss) Recognized in Income	(267)	287	(163)	(82)
Derivatives Not Designated As Hedging Instruments | Foreign Exchange Forward
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain (Loss) Recognized in Income	$ (267)	$ 287	$ (163)	$ (82)

Inventories, net (Details)

Inventories, net (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Inventory Disclosure [Abstract]
Raw materials	$ 110,773	$ 110,078
Work-in-process	12,235	10,613
Finished goods	86,550	79,719
Total	$ 209,558	$ 200,410

Intangible assets and goodwil_3

Intangible assets and goodwill, net - Schedule Of Finite-Lived Intangible Assets (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	$ 339,693	$ 304,788
Accumulated Amortization	(156,626)	(220,705)
Net Carrying Amount	183,067	84,083
Capitalized software development costs
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	123,483	132,789
Accumulated Amortization	(86,096)	(76,910)
Net Carrying Amount	37,387	55,879
Acquired technology
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	105,008	91,900
Accumulated Amortization	(14,726)	(87,917)
Net Carrying Amount	90,282	3,983
Patents
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	36,531	35,609
Accumulated Amortization	(26,008)	(23,993)
Net Carrying Amount	10,523	11,616
Other
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	74,671	44,490
Accumulated Amortization	(29,796)	(31,885)
Net Carrying Amount	$ 44,875	$ 12,605

Intangible assets and goodwil_4

Intangible assets and goodwill, net - Narrative (Details)	3 Months Ended		9 Months Ended
	Sep. 30, 2020USD ($)	Sep. 30, 2019USD ($)	Sep. 30, 2020USD ($)reporting_unitsegment	Sep. 30, 2019USD ($)
Finite-Lived Intangible Assets [Line Items]
Amortization of intangible assets	$ 14,200,000	$ 9,200,000	$ 32,900,000	$ 27,300,000
Number of operating segments | segment			1
Number of reporting units | reporting_unit			1
Goodwill impairment			$ 0
Capitalized Software Development Costs
Finite-Lived Intangible Assets [Line Items]
Capitalized Computer Software, Impairments	(200,000)
Software development costs capitalized		2,800,000	3,100,000	7,500,000
Amortization expense of capitalized software development costs	6,900,000	7,100,000	21,600,000	20,900,000
Costs related to stock based compensation	$ 100,000	$ 200,000	$ 300,000	$ 300,000
Minimum | Capitalized Software Development Costs
Finite-Lived Intangible Assets [Line Items]
Intangible assets amortization period (in years)			3 years
Minimum | Acquired Technology
Finite-Lived Intangible Assets [Line Items]
Intangible assets amortization period (in years)			3 years
Minimum | Patents
Finite-Lived Intangible Assets [Line Items]
Intangible assets amortization period (in years)			10 years
Maximum | Capitalized Software Development Costs
Finite-Lived Intangible Assets [Line Items]
Intangible assets amortization period (in years)			6 years
Maximum | Acquired Technology
Finite-Lived Intangible Assets [Line Items]
Intangible assets amortization period (in years)			8 years
Maximum | Patents
Finite-Lived Intangible Assets [Line Items]
Intangible assets amortization period (in years)			17 years

Intangible assets and goodwil_5

Intangible assets and goodwill, net - Schedule of Goodwill (Details) - USD ($) $ in Thousands	9 Months Ended	12 Months Ended
	Sep. 30, 2020	Dec. 31, 2019
Goodwill [Roll Forward]
Balance as of December 31, 2019	$ 262,242
Acquisition		$ 227,280
Foreign currency translation impact	4,800
Divestiture	(7,221)
Balance as of September 30, 2020 (unaudited)	$ 487,101	$ 262,242

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, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Lessee, Lease, Description [Line Items]
Operating lease cost	$ 4,869	$ 5,456	$ 15,941	$ 16,951
Minimum
Lessee, Lease, Description [Line Items]
Operating leases, weighted average remaining lease term (in years)			1 year
Maximum
Lessee, Lease, Description [Line Items]
Operating leases, weighted average remaining lease term (in years)			94 years
Operating lease, renewal term (in years)	9 years		9 years

Leases - Maturities of Operatin

Leases - Maturities of Operating Lease Liabilities (Details) $ in Thousands	Sep. 30, 2020USD ($)
Leases [Abstract]
2020 (Excluding the nine months ended September 30, 2020)	$ 7,012
2020	17,340
2021	11,465
2022	8,229
2023	7,062
Thereafter	14,161
Total future minimum lease payments	65,269
Less imputed interest	(11,325)
Total	$ 53,944

Income taxes (Details)

Income taxes (Details) - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019	Dec. 31, 2019
Operating Loss Carryforwards [Line Items]
Valuation allowance	$ 102,000,000		$ 102,000,000		$ 86,000,000
Unrecognized tax benefits	6,900,000		6,900,000		$ 6,700,000
Unrecognized tax benefits, period increase (decrease)	0
Reasonable possibility of future tax benefits	2,900,000		2,900,000
Accrued interest related to uncertain tax positions	$ 800,000		$ 800,000
Effective income tax rate	(11.00%)	23.00%	24.00%	18.00%
U.S. federal statutory rate	21.00%	21.00%		21.00%
Hungary statutory tax rate			9.00%
Income tax benefit of tax holiday (in usd per share)	$ 0.01	$ 0.01	$ 0.01	$ 0.02
Hungary
Operating Loss Carryforwards [Line Items]
Foreign income tax benefit	$ 100,000	$ 1,600,000	$ 300,000	$ 4,200,000
Malaysia
Operating Loss Carryforwards [Line Items]
Income tax benefit of tax holiday, amount	$ 200,000	$ 1,800,000	$ 400,000	$ 3,100,000

Comprehensive income (Details)

Comprehensive income (Details) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning Balance	$ 1,176,350	$ 1,238,358
Current-period other comprehensive income (loss)	(1,509)	862
Reclassified from accumulated OCI into income	(2,429)	(7,312)
Income tax expense (benefit)	(2,268)	355
Ending Balance	1,239,198	1,162,161
Currency translation adjustment
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning Balance	(25,831)	(22,485)
Current-period other comprehensive income (loss)	6,507	(9,303)
Reclassified from accumulated OCI into income	0	0
Income tax expense (benefit)	0	0
Ending Balance	(19,324)	(31,788)
Investments
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning Balance	(85)	(1,308)
Current-period other comprehensive income (loss)	(317)	1,494
Reclassified from accumulated OCI into income	0	0
Income tax expense (benefit)	(45)	(11)
Ending Balance	(357)	197
Derivative instruments
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning Balance	4,846
Current-period other comprehensive income (loss)	(7,699)
Reclassified from accumulated OCI into income	(2,429)
Income tax expense (benefit)	(2,223)
Ending Balance	(3,059)
Derivative instruments
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning Balance		6,862
Current-period other comprehensive income (loss)		8,671
Reclassified from accumulated OCI into income		(7,312)
Income tax expense (benefit)		366
Ending Balance		7,855
Accumulated other comprehensive income/(loss)
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning Balance	(21,070)	(16,931)
Ending Balance	$ (22,740)	$ (23,736)

Authorized shares of common a_3

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

Jan. 01, 2019

May 14, 2013

Sep. 30, 2020

Sep. 30, 2019

Sep. 30, 2020

Sep. 30, 2019

May 05, 2020

Dec. 31, 2019

May 14, 2019

May 12, 2015

May 11, 2010

May 31, 2005

Jan. 21, 2004

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

Additional number of shares reserved for issuance (in shares)

180,000,000

Common stock, authorized (in shares)

360,000,000

360,000,000

360,000,000

360,000,000

Common and preferred stock shares authorized (in shares)

365,000,000

Preferred stock, authorized (in shares)

5,000,000

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

$ 0.01

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

$ 0.01

$ 0.01

$ 0.01

$ 0.01

Number of shares reserved for issuance (in shares)

2,518,416

3,362,304

Preferred stock, issued (in shares)

0

0

0

Preferred stock, outstanding (in shares)

0

0

0

Common stock repurchased (in shares)

446,502

1,056,078

1,114,701

3,205,676

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

$ 34.86

$ 42.42

$ 35.21

$ 42.79

Authorized common stock available for repurchase (in shares)

1,885,299

1,885,299

Performance Shares

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

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

144,647

92,809

Share-based compensation arrangement by share-based payment award, award requisite service period

3 years

3 years

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

$ 61

$ 57.46

$ 61

$ 57.46

Incentive Plan (2005) | Restricted Stock Plan

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

Number of shares reserved for issuance (in shares)

4,050,000

Incentive Plan (2005) | Restricted Stock Plan | One to three year vesting period

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

Award vesting period (in years)

3 years

Incentive Plan (2005) | Restricted Stock Plan | Three to Five year vesting period

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

Award vesting period (in years)

5 years

Incentive Plan (2005) | Restricted Stock Plan | Ten year vesting period

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

Award vesting period (in years)

10 years

Incentive Plan (2010)

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

Number of shares reserved for issuance (in shares)

2,518,416

Incentive Plan (2010) | Restricted Stock Plan

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

Common stock, authorized (in shares)

3,000,000

Incentive Plan (2010) | Restricted Stock Plan | One to three year vesting period

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

Award vesting period (in years)

3 years

Incentive Plan (2010) | Restricted Stock Plan | Three to Five year vesting period

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

Award vesting period (in years)

5 years

Incentive Plan (2010) | Restricted Stock Plan | Ten year vesting period

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

Award vesting period (in years)

10 years

Incentive Plan (2015)

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

Incentive Plan (2015) | Restricted Stock Plan | One to three year vesting period

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

Award vesting period (in years)

3 years

Incentive Plan (2015) | Restricted Stock Plan | Three to Five year vesting period

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

Award vesting period (in years)

5 years

Incentive Plan (2015) | Restricted Stock Plan | Ten year vesting period

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

Award vesting period (in years)

10 years

Incentive Plan (2015) | Restricted Stock Plan | Four year vesting period

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

Award vesting period (in years)

4 years

Incentive Plan (2020)

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)

5,141,465

5,141,465

Incentive Plan (2020) | Restricted Stock Plan | One to three year vesting period

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

Award vesting period (in years)

1 year

Incentive Plan (2020) | Restricted Stock Plan | Three to Five year vesting period

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

Award vesting period (in years)

3 years

Incentive Plan (2020) | Restricted Stock Plan | Four year vesting period

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

Award vesting period (in years)

4 years

Employee Stock Purchase Plan

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)

3,321,597

3,321,597

Shares issued under employee stock purchase plan (in shares)

764,173

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

$ 32.67

Series A Preferred Stock

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

Preferred stock, authorized (in shares)

750,000

Authorized shares of common a_4

Authorized shares of common and preferred stock and stock-based compensation plans - Schedule of Performance Activity (Details) - Performance Shares - numberOfSimulations	9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of simulations	100,000	100,000
Expected volatility	27.41%	26.08%
Expected life in years	2 years 11 months 1 day	2 years 11 months 8 days
Risk-free interest rate	1.38%	2.52%
Dividend yield	2.32%	1.96%

Segment and geographic inform_2

Segment and geographic information (Details) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2020USD ($)	Sep. 30, 2019USD ($)	Sep. 30, 2020USD ($)regionsegment	Sep. 30, 2019USD ($)	Dec. 31, 2019USD ($)
Revenues from External Customers and Long-Lived Assets [Line Items]
Number of operating segments | segment			1
Number of geographic regions company operates in | region			3
Total revenue	$ 308,124	$ 340,442	$ 918,834	$ 985,747
Property and equipment, net	253,073		253,073		$ 243,717
Outside The United States
Revenues from External Customers and Long-Lived Assets [Line Items]
Total revenue	187,000	$ 208,000	564,000	$ 617,000
Property and equipment, net	$ 135,000		$ 135,000		$ 130,000

Debt (Details)

Debt (Details) - USD ($)	Jun. 12, 2020	Sep. 30, 2020
Letter of Credit | Line of Credit | Wells Fargo Securities, LLC
Line of Credit Facility [Line Items]
Unsecured revolving line of credit	$ 10,000,000
Revolving Credit Facility | Line of Credit | Wells Fargo Securities, LLC
Line of Credit Facility [Line Items]
Unsecured revolving line of credit	145,000,000
Line of credit, accordion feature, higher borrowing capacity feature	105,000,000
Secured Revolving Loan Facility | Line of Credit | Wells Fargo Securities, LLC
Line of Credit Facility [Line Items]
Unsecured revolving line of credit	75,000,000
Secured Term Loan Facility | Line of Credit | Wells Fargo Securities, LLC
Line of Credit Facility [Line Items]
Unsecured revolving line of credit	$ 70,000,000
Line of credit facility, expiration period	60 days
2020 term loan (effective interest rate of 3.0%)
Line of Credit Facility [Line Items]
Debt instrument, interest rate, stated percentage		3.00%
Credit Agreement
Line of Credit Facility [Line Items]
Debt instrument, covenant, leverage ratio, maximum	2.75
Debt instrument, covenant, liquidity ratio leverage, minimum	1.25
Minimum | Credit Agreement | Revolving Credit Facility
Line of Credit Facility [Line Items]
Quarterly commitment fee	0.375%
Maximum | Credit Agreement | Revolving Credit Facility
Line of Credit Facility [Line Items]
Quarterly commitment fee	0.50%
Base Rate | Revolving Credit Facility
Line of Credit Facility [Line Items]
Debt instrument, interest rate, stated percentage	0.50%
Base Rate | Secured Term Loan Facility
Line of Credit Facility [Line Items]
Debt instrument, interest rate, stated percentage	1.25%
Base Rate | Minimum | Credit Agreement | Revolving Credit Facility
Line of Credit Facility [Line Items]
Variable interest rate spread	1.25%
Base Rate | Maximum | Credit Agreement | Revolving Credit Facility
Line of Credit Facility [Line Items]
Variable interest rate spread	1.75%
London Interbank Offered Rate | Revolving Credit Facility
Line of Credit Facility [Line Items]
Debt instrument, interest rate, stated percentage	1.00%
London Interbank Offered Rate | Minimum | Credit Agreement | Revolving Credit Facility
Line of Credit Facility [Line Items]
Variable interest rate spread	2.25%
Quarterly commitment fee	0.375%
Debt instrument, default interest rate	2.00%
London Interbank Offered Rate | Maximum | Credit Agreement | Revolving Credit Facility
Line of Credit Facility [Line Items]
Variable interest rate spread	2.75%
Quarterly commitment fee	0.50%

Debt - Schedule of Long-term De

Debt - Schedule of Long-term Debt (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Debt Instrument [Line Items]
Total Debt	$ 89,125	$ 0
Less: Unamortized debt issuance costs	(1,336)	0
Less: Current Portion of Total Debt	(3,500)	0
Total Debt, non-current	$ 84,289	0
2020 term loan (effective interest rate of 3.0%)
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage	3.00%
Total Debt	$ 69,125	0
2020 revolving loan facility (effective interest rate of 3.0%)
Debt Instrument [Line Items]
Total Debt	$ 20,000	$ 0

Commitments and contingencies -

Commitments and contingencies - Schedule Of Warranty Reserve (Details) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019
Movement in Standard Product Warranty Accrual [Roll Forward]
Balance at the beginning of the period	$ 2,561	$ 3,173
Accruals for warranties issued during the period	1,824	1,665
Accruals related to pre-existing warranties	405	(441)
Settlements made (in cash or in kind) during the period	(2,088)	(1,899)
Balance at the end of the period	$ 2,702	$ 2,498

Commitments and contingencies_2

Commitments and contingencies - Narrative (Details) $ in Millions	9 Months Ended
	Sep. 30, 2020USD ($)
Commitments and Contingencies Disclosure [Abstract]
Limited warranty on most hardware products (in number of years)	1 year
Non-cancelable purchase commitments	$ 5.2

Restructuring - Schedule of Res

Restructuring - Schedule of Restructuring Related Costs (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Restructuring Cost and Reserve [Line Items]
Total restructuring and other related costs	$ 658	$ 4,017	$ 13,461	$ 11,160
Cost of sales
Restructuring Cost and Reserve [Line Items]
Total restructuring and other related costs	(13)	0	7	0
Research and development
Restructuring Cost and Reserve [Line Items]
Total restructuring and other related costs	38	34	4,716	690
Sales and marketing
Restructuring Cost and Reserve [Line Items]
Total restructuring and other related costs	512	2,993	8,055	7,958
General and administrative
Restructuring Cost and Reserve [Line Items]
Total restructuring and other related costs	$ 121	$ 990	$ 683	$ 2,512

Restructuring - Schedule of R_2

Restructuring - Schedule of Restructuring Reserve (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Restructuring Reserve [Roll Forward]
Balance as of December 31, 2018			$ 9,527
Income statement expense	$ 658	$ 4,017	13,461	$ 11,160
Cash payments			(19,651)
Balance as of September 30, 2020	$ 3,337		$ 3,337

Restructuring - Narrative (Deta

Restructuring - Narrative (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Restructuring and Related Activities [Abstract]
Restructuring accrual	$ 3,337	$ 9,527

Acquisitions - Narrative (Detai

Acquisitions - Narrative (Details) - USD ($)	Jul. 02, 2020	Jun. 30, 2020	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019	Jan. 15, 2020
Business Acquisition [Line Items]
Proceeds from term loan					$ 70,000,000	$ 0
Business acquisition, transaction costs							$ 1,000,000
Secured Term Loan Facility | Wells Fargo Securities, LLC | Line of Credit
Business Acquisition [Line Items]
Proceeds from term loan		$ 70,000,000
OptimalPlus Ltd
Business Combinations [Abstract]
Business acquisition, percentage of voting interests acquired	100.00%
Consideration Transferred	$ 352,642,000
Business Acquisition [Line Items]
Business acquisition, percentage of voting interests acquired	100.00%
Business acquisition, transaction costs			$ 7,000,000		7,000,000
Cash acquired from acquisition	$ 18,000,000
Business combination, deferred cash consideration	$ 12,000,000
Net sales			309,142,000	$ 348,401,000	929,381,000	1,009,102,000
Net (loss) attributable to NI			$ 4,907,000	$ 42,522,000	$ 123,766,000	$ 65,796,000

Acquisitions - Schedule of Busi

Acquisitions - Schedule of Business Acquisition, by Acquisition (Details) - USD ($) $ in Thousands	Jul. 02, 2020	Sep. 30, 2020	Dec. 31, 2019
Business Acquisition [Line Items]
Intangible assets	$ 127,600
Goodwill		$ 487,101	$ 262,242
OptimalPlus Ltd
Business Acquisition [Line Items]
Consideration Transferred	352,642
Cash	17,661
Goodwill	227,280
Contract assets	15,454
Deferred revenue	(7,341)
Accounts receivable	4,927
Other assets and liabilities	(2,545)
Deferred tax liabilities	(30,394)
Net assets acquired	$ 352,642

Acquisitions - Schedule of Reco

Acquisitions - Schedule of Recognized Identified Assets Acquired and Liabilities Assumed (Details) $ in Thousands	Jul. 02, 2020USD ($)
Customer relationships
Business Acquisition [Line Items]
Acquired finite-lived intangible assets, weighted average useful life	5 years
Acquired technology
Business Acquisition [Line Items]
Acquired finite-lived intangible assets, weighted average useful life	6 years
In-process research and development (IPR&D)
Business Acquisition [Line Items]
Acquired finite-lived intangible assets, weighted average useful life	6 years
Other | Minimum
Business Acquisition [Line Items]
Acquired finite-lived intangible assets, weighted average useful life	3 years
Other | Maximum
Business Acquisition [Line Items]
Acquired finite-lived intangible assets, weighted average useful life	5 years
OptimalPlus Ltd
Business Acquisition [Line Items]
Estimated Fair Value	$ 127,600
OptimalPlus Ltd | Customer relationships
Business Acquisition [Line Items]
Estimated Fair Value	30,100
OptimalPlus Ltd | Acquired technology
Business Acquisition [Line Items]
Estimated Fair Value	81,400
OptimalPlus Ltd | In-process research and development (IPR&D)
Business Acquisition [Line Items]
Estimated Fair Value	10,200
OptimalPlus Ltd | Other
Business Acquisition [Line Items]
Estimated Fair Value	$ 5,900

Acquisitions - Business Combina

Acquisitions - Business Combination, Pro Forma Information (Details) - OptimalPlus Ltd - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Business Acquisition [Line Items]
Net sales	$ 309,142	$ 348,401	$ 929,381	$ 1,009,102
Net (loss) attributable to NI	$ 4,907	$ 42,522	$ 123,766	$ 65,796

Subsequent events (Details)

Subsequent events (Details)	Oct. 30, 2020USD ($)	Oct. 29, 2020USD ($)	Jun. 12, 2020	Oct. 28, 2020$ / shares
Subsequent Event
Subsequent Event [Line Items]
Dividend payable (in usd per share) | $ / shares				$ 0.26
Workforce reduction, percent		9.00%
Subsequent Event | Minimum
Subsequent Event [Line Items]
Workforce reduction, term		9 months
Expected restructuring costs		$ 22,000,000
Subsequent Event | Maximum
Subsequent Event [Line Items]
Workforce reduction, term		12 months
Expected restructuring costs		$ 28,000,000
Credit Agreement
Subsequent Event [Line Items]
Debt instrument, covenant, leverage ratio, maximum			2.75
Revolving Credit Facility | Credit Agreement | Minimum
Subsequent Event [Line Items]
Quarterly commitment fee			0.375%
Revolving Credit Facility | Credit Agreement | Maximum
Subsequent Event [Line Items]
Quarterly commitment fee			0.50%
Revolving Credit Facility | Credit Agreement | London Interbank Offered Rate | Minimum
Subsequent Event [Line Items]
Variable interest rate spread			2.25%
Quarterly commitment fee			0.375%
Revolving Credit Facility | Credit Agreement | London Interbank Offered Rate | Maximum
Subsequent Event [Line Items]
Variable interest rate spread			2.75%
Quarterly commitment fee			0.50%
Revolving Credit Facility | Credit Agreement | Base Rate | Minimum
Subsequent Event [Line Items]
Variable interest rate spread			1.25%
Revolving Credit Facility | Credit Agreement | Base Rate | Maximum
Subsequent Event [Line Items]
Variable interest rate spread			1.75%
Revolving Credit Facility | Credit Agreement | Subsequent Event
Subsequent Event [Line Items]
Unsecured revolving line of credit	$ 115,000,000	$ 75,000,000
Debt instrument, covenant, leverage ratio, maximum	2.25
Debt instrument, installment payments, percentage of the principal amount	1.25%
Revolving Credit Facility | Credit Agreement | Subsequent Event | Minimum
Subsequent Event [Line Items]
Quarterly commitment fee	0.25%	0.375%
Revolving Credit Facility | Credit Agreement | Subsequent Event | Maximum
Subsequent Event [Line Items]
Quarterly commitment fee	0.375%	0.50%
Revolving Credit Facility | Credit Agreement | Subsequent Event | London Interbank Offered Rate | Minimum
Subsequent Event [Line Items]
Variable interest rate spread	1.50%
Revolving Credit Facility | Credit Agreement | Subsequent Event | London Interbank Offered Rate | Maximum
Subsequent Event [Line Items]
Variable interest rate spread	2.00%
Revolving Credit Facility | Credit Agreement | Subsequent Event | Base Rate | Minimum
Subsequent Event [Line Items]
Variable interest rate spread	0.50%
Revolving Credit Facility | Credit Agreement | Subsequent Event | Base Rate | Maximum
Subsequent Event [Line Items]
Variable interest rate spread	1.00%
Revolving Credit Facility | Secured Term Loan Facility | Subsequent Event
Subsequent Event [Line Items]
Long-term line of credit	$ 70,000,000
Line of credit facility, accordion feature, increase limit	$ 100,000,000