MKS Instruments (MKSI) 10-K 28 Feb 18 2017 FY Annual report Financial data

Document and Entity Information

Document and Entity Information - USD ($)	12 Months Ended
	Dec. 31, 2017	Feb. 21, 2018	Jun. 30, 2017
Document And Entity Information [Abstract]
Document Type	10-K
Amendment Flag	false
Document Period End Date	Dec. 31, 2017
Document Fiscal Year Focus	2,017
Document Fiscal Period Focus	FY
Trading Symbol	MKSI
Entity Registrant Name	MKS INSTRUMENTS INC
Entity Central Index Key	1,049,502
Current Fiscal Year End Date	--12-31
Entity Well-known Seasoned Issuer	Yes
Entity Current Reporting Status	Yes
Entity Voluntary Filers	No
Entity Filer Category	Large Accelerated Filer
Entity Common Stock, Shares Outstanding		54,487,946
Entity Public Float			$ 3,638,472,244

Consolidated Balance Sheets

Consolidated Balance Sheets - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Current assets:
Cash and cash equivalents	$ 333,768	$ 228,623
Restricted cash	119	5,287
Short-term investments	209,434	189,463
Trade accounts receivable, net of allowance for doubtful accounts of $4,135 and $3,909 at December 31, 2017 and 2016, respectively	300,308	248,757
Inventories	339,081	275,869
Other current assets	53,543	50,770
Total current assets	1,236,253	998,769
Property, plant and equipment, net	171,782	174,559
Goodwill	591,047	588,585
Intangible assets, net	366,398	408,004
Long-term investments	10,655	9,858
Other assets	37,883	32,467
Total assets	2,414,018	2,212,242
Current liabilities:
Short-term debt	2,972	10,993
Accounts payable	82,518	69,337
Accrued compensation	96,147	67,728
Income taxes payable	21,398	22,794
Deferred revenue	12,842	14,463
Other current liabilities	73,945	51,985
Total current liabilities	289,822	237,300
Long-term debt, net	389,993	601,229
Non-current deferred taxes	61,571	66,446
Non-current accrued compensation	51,700	44,714
Other liabilities	32,025	20,761
Total liabilities	825,111	970,450
Commitments and contingencies (Note 21)
Stockholders' equity:
Preferred stock, $0.01 par value, 2,000,000 shares authorized; none issued and outstanding
Common stock, no par value, 200,000,000 shares authorized; 54,355,535 and 53,672,861 shares issued and outstanding at December 31, 2017 and 2016, respectively	113	113
Additional paid-in capital	789,644	777,482
Retained earnings	795,698	494,744
Accumulated other comprehensive loss	3,452	(30,547)
Total stockholders' equity	1,588,907	1,241,792
Total liabilities and stockholders' equity	$ 2,414,018	$ 2,212,242

Consolidated Balance Sheets (Pa

Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Statement of Financial Position [Abstract]
Allowance for doubtful accounts	$ 4,135	$ 3,909
Preferred stock, par value	$ 0.01	$ 0.01
Preferred stock, shares authorized	2,000,000	2,000,000
Preferred stock, shares issued	0	0
Preferred stock, shares outstanding	0	0
Common stock, par value	$ 0	$ 0
Common stock, shares authorized	200,000,000	200,000,000
Common stock, shares issued	54,355,535	53,672,861
Common stock, shares outstanding	54,355,535	53,672,861

Consolidated Statements of Oper

Consolidated Statements of Operations and Comprehensive Income - USD ($) shares in Thousands, $ in Thousands		12 Months Ended
		Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Net Revenues:
Products		$ 1,723,433	$ 1,134,013	$ 697,104
Services		192,544	161,329	116,420
Total net revenues		1,915,977	1,295,342	813,524
Cost of revenues:
Cost of products		901,546	627,850	373,764
Cost of service		122,980	101,873	76,888
Total cost of revenues (exclusive of amortization shown separately below)		1,024,526	729,723	450,652
Gross profit		891,451	565,619	362,872
Research and development		132,555	110,579	68,305
Selling, general and administrative		290,548	229,171	129,087
Acquisition and integration costs		5,332	27,279	30
Restructuring		3,920	642	2,074
Asset impairment		6,719	5,000
Amortization of intangible assets		45,743	35,681	6,764
Income from operations		406,634	157,267	156,612
Interest income		3,021	2,560	2,999
Interest expense		30,990	30,611	143
Gain on sale of business		74,856
Other expense, net		5,896	1,239
Income before income taxes		447,625	127,977	159,468
Provision for income taxes		108,493	23,168	37,171
Net income		339,132	104,809	122,297
Other comprehensive income:
Changes in value of financial instruments designated as cash flow hedges, net of tax (benefit) expense(1)	[1]	(4,568)	3,380	(469)
Foreign currency translation adjustments, net of tax of $0 for 2017, 2016 and 2015		37,172	(22,713)	(8,301)
Unrecognized pension gain (loss), net of tax benefit(2)	[2]	323	(266)
Unrealized gain (loss) on investments, net of tax (benefit) expense(3)	[3]	1,072	223	(317)
Total comprehensive income		$ 373,131	$ 85,433	$ 113,210
Net income per share:
Basic		$ 6.26	$ 1.96	$ 2.30
Diluted		6.16	1.94	2.28
Cash dividends paid per common share		$ 0.71	$ 0.68	$ 0.68
Weighted average common shares outstanding:
Basic		54,137	53,472	53,282
Diluted		55,074	54,051	53,560
[1]	Tax (benefit) expense was $(1,468), $2,535 and $(85) for the years ended December 31, 2017, 2016 and 2015, respectively.
[2]	Tax benefit was $(88) and $(199) for the years ended December 31, 2017 and 2016, respectively, and $0 for 2015.
[3]	Tax (benefit) expense was $(769), $167, and $(58) for the years ended December 31, 2017, 2016 and 2015, respectively.

Consolidated Statements of Ope5

Consolidated Statements of Operations and Comprehensive Income (Parenthetical) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Income Statement [Abstract]
Tax expense (benefit) on changes in value of financial instruments designated as cash flow hedges	$ (1,468)	$ 2,535	$ (85)
Tax on foreign currency translation adjustments	0	0	0
Tax benefit on unrecognized net pension loss	(88)	(199)	0
Tax expense (benefit) on unrealized gain (loss) on investments	$ (769)	$ 167	$ (58)

Consolidated Statements of Stoc

Consolidated Statements of Stockholders' Equity - USD ($) $ in Thousands	Total	Common Stock [Member]	Additional Paid-In Capital [Member]	Retained Earnings [Member]	Accumulated Other Comprehensive Income/(Loss) [Member]
Beginning Balance at Dec. 31, 2014	$ 1,081,822	$ 113	$ 734,732	$ 349,061	$ (2,084)
Beginning Balance, Shares at Dec. 31, 2014		53,154,666
Net issuance under stock-based plans	1,262		1,262
Net issuance under stock-based plans, Shares		414,187
Stock-based compensation	13,013		13,013
Tax effect from stock-based plans	837		837
Stock repurchase	(13,294)		(5,119)	(8,175)
Stock repurchase, shares		(369,133)
Cash dividend	(35,969)			(35,969)
Comprehensive income (net of tax):
Net issuance under stock-based plans	1,262		1,262
Net issuance under stock-based plans, Shares		414,187
Stock-based compensation	13,013		13,013
Tax effect from stock-based plans	837		837
Stock repurchase	(13,294)		(5,119)	(8,175)
Stock repurchase, shares		(369,133)
Cash dividend	(35,969)			(35,969)
Net income	122,297			122,297
Other comprehensive loss	(9,087)				(9,087)
Ending Balance at Dec. 31, 2015	1,160,881	$ 113	744,725	427,214	(11,171)
Ending Balance, Shares at Dec. 31, 2015		53,199,720
Ending Balance, Shares at Dec. 31, 2015		53,199,720
Net issuance under stock-based plans	6,902		6,902
Net issuance under stock-based plans, Shares		517,939
Stock-based compensation	25,228		25,228
Tax effect from stock-based plans	1,254		1,254
Stock repurchase	$ (1,545)		(627)	(918)
Stock repurchase, shares	(44,798)	(44,798)
Cash dividend	$ (36,361)			(36,361)
Comprehensive income (net of tax):
Net issuance under stock-based plans	6,902		6,902
Net issuance under stock-based plans, Shares		517,939
Stock-based compensation	25,228		25,228
Tax effect from stock-based plans	1,254		1,254
Stock repurchase	$ (1,545)		(627)	(918)
Stock repurchase, shares	(44,798)	(44,798)
Cash dividend	$ (36,361)			(36,361)
Net income	104,809			104,809
Other comprehensive loss	(19,376)				(19,376)
Ending Balance at Dec. 31, 2016	1,241,792	$ 113	777,482	494,744	(30,547)
Ending Balance, Shares at Dec. 31, 2016		53,672,861
Ending Balance, Shares at Dec. 31, 2016		53,672,861
Net issuance under stock-based plans	(12,216)		(12,216)
Net issuance under stock-based plans, Shares		682,674
Stock-based compensation	$ 24,378		24,378
Stock repurchase, shares	0
Cash dividend	$ (38,178)			(38,178)
Comprehensive income (net of tax):
Net issuance under stock-based plans	(12,216)		(12,216)
Net issuance under stock-based plans, Shares		682,674
Stock-based compensation	$ 24,378		24,378
Stock repurchase, shares	0
Cash dividend	$ (38,178)			(38,178)
Net income	339,132			339,132
Other comprehensive loss	33,999				33,999
Ending Balance at Dec. 31, 2017	$ 1,588,907	$ 113	$ 789,644	$ 795,698	$ 3,452
Ending Balance, Shares at Dec. 31, 2017		54,355,535
Ending Balance, Shares at Dec. 31, 2017		54,355,535

Consolidated Statements of Cash

Consolidated Statements of Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Cash flows from operating activities:
Net income	$ 339,132	$ 104,809	$ 122,297
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	82,556	65,926	22,103
Amortization of inventory step-up adjustment to fair value		15,090
Amortization of debt issuance cost and original issue discount	10,699	9,265
Stock-based compensation	24,378	25,228	13,013
Provision for excess and obsolete inventory	20,213	16,039	13,602
Provision for doubtful accounts	825	1,109	(255)
Deferred income taxes	(4,831)	(38,822)	410
Excess tax benefits from stock-based compensation		(1,468)	(904)
Asset impairment	6,719	5,000
Gain on sale of business	(74,856)
Other	824	256	275
Changes in operating assets and liabilities:
Trade accounts receivable	(44,077)	(58,111)	2,334
Inventories	(72,471)	(13,798)	(14,501)
Income taxes	12,805	30,914	(8,462)
Other current and non-current assets	(8,631)	(12,165)	(1,526)
Accrued compensation	32,502	10,965	3,335
Other current and non-current liabilities	18,030	3,681	(2,797)
Accounts payable	11,405	16,180	(10,629)
Net cash provided by operating activities	355,222	180,098	138,295
Cash flows from investing activities:
Acquisition of business, net of cash acquired		(939,591)	(9,910)
Net proceeds from sale of business	72,509
Purchases of investments	(229,557)	(268,458)	(385,999)
Maturities of investments	157,342	160,917	179,285
Sales of investments	53,564	338,996	61,659
Purchases of property, plant and equipment	(31,287)	(19,123)	(12,414)
Other	66	273	8
Net cash provided by (used in) investing activities	22,637	(726,986)	(167,371)
Cash flows from financing activities:
Restricted cash	4,835	(5,860)
Proceeds from short-term borrowings	28,360	18,964
Payments of short-term borrowings	(29,711)	(11,742)
Proceeds from long-term borrowings	191	744,653
Payments of long-term borrowings	(228,141)	(153,395)
Repurchases of common stock		(1,545)	(13,294)
Net proceeds related to employee stock awards	(12,216)	(1,922)	1,262
Dividend payments	(38,178)	(36,361)	(35,969)
Excess tax benefit from stock-based compensation		1,468	904
Net cash (used in) provided by financing activities	(274,860)	554,260	(47,097)
Effect of exchange rate changes on cash and cash equivalents	2,146	(6,323)	(1,690)
Increase (decrease) in cash and cash equivalents	105,145	1,049	(77,863)
Cash and cash equivalents at beginning of year	228,623	227,574	305,437
Cash and cash equivalents at end of year	333,768	228,623	227,574
Cash paid during the period for:
Interest	20,467	20,839	34
Income taxes	$ 104,691	$ 44,967	$ 43,239

Business Description

Business Description	12 Months Ended
	Dec. 31, 2017
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Business Description	1) Business Description MKS Instruments, Inc. (“MKS” or the “Company”) was founded in 1961 and is a global provider of instruments, subsystems and process control solutions that measure, monitor, deliver, analyze, power and control critical parameters of advanced manufacturing processes to improve process performance and productivity. The Company’s products are derived from its core competencies in pressure measurement and control, flow measurement and control, gas and vapor delivery, gas composition analysis, residual gas analysis, leak detection, control technology, ozone generation and delivery, RF & DC power, reactive gas generation, vacuum technology, lasers, photonics, sub-micron The Company has two reportable segments: Vacuum & Analysis and Light & Motion.

Basis of Presentation

Basis of Presentation	12 Months Ended
	Dec. 31, 2017
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Basis of Presentation	2) Basis of Presentation The consolidated financial statements include the accounts of MKS Instruments, Inc. and its wholly owned subsidiaries. All intercompany accounts and transactions have been eliminated in consolidation. Use of Estimates The consolidated financial statements have been prepared in accordance with accounting principles generally accepted in the United States of America (“U.S. GAAP”). The preparation of these financial statements requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and the disclosure of contingent liabilities at the date of the financial statements and the reported amounts of revenues and expenses during the reporting period. On an on-going

Summary of Significant Accounti

Summary of Significant Accounting Policies	12 Months Ended
	Dec. 31, 2017
Accounting Policies [Abstract]
Summary of Significant Accounting Policies	3) Summary of Significant Accounting Policies Revenue Recognition and Accounts Receivable Allowances Revenue from product sales is recorded upon transfer of title and risk of loss to the customer provided that there is evidence of an arrangement, the sales price is fixed or determinable, and collection of the related receivable is reasonably assured. In most transactions, the Company has no obligations to customers after the date products are shipped other than pursuant to warranty obligations. In some instances, the Company provides installation, training, support and services to customers after the product has been shipped. For those revenue arrangements with multiple deliverables, the Company allocates revenue to each element based upon its relative selling price using vendor-specific objective evidence (“VSOE”), or third-party evidence (“TPE”) or based upon the relative selling price using estimated prices if VSOE or TPE does not exist. The Company then recognizes revenue on each deliverable in accordance with its policies for product and service revenue recognition. The Company provides for the estimated costs to fulfill customer warranty obligations upon the recognition of the related revenue. Shipping and handling fees, if any, billed to customers are recognized as revenue. The related shipping and handling costs are recognized in cost of revenues. Accounts receivable allowances include sales returns and bad debt allowances. The Company monitors and tracks the amount of product returns and reduces revenue at the time of shipment for the estimated amount of such future returns, based on historical experience. The Company makes estimates evaluating its allowance for doubtful accounts. The Company continuously monitors collections and payments from its customers and maintains a provision for estimated credit losses based upon its historical experience and any specific customer collection issues that it has identified. Research and Development Research and development costs are expensed as incurred and consist mainly of compensation-related expenses and project materials. The Company’s research and development efforts include numerous projects, which generally have a duration of 3 to 30 months. Acquired in-process Advertising Costs Advertising costs are expensed as incurred and were immaterial in 2017, 2016 and 2015. Stock-Based Compensation The accounting for share-based compensation expense requires the measurement and recognition of compensation expense for all share-based payment awards made to employees and directors based on estimated fair values. For restricted stock units (“RSUs”), the fair value is the fair value on the date of grant that normally vests over a three year period. The Company also provides employees the opportunity to purchase shares through an employee stock purchase plan. For shares issued under its employee stock purchase plan, the Company has estimated the fair value on the date of grant using the Black Scholes pricing model, which is affected by the Company’s stock price as well as assumptions regarding a number of complex and subjective variables. These variables include the Company’s expected stock price volatility over the term of the awards, expected life, risk-free interest rate and expected dividends. The Company is also required to estimate forfeitures at the time of grant and revise those estimates in subsequent periods if actual forfeitures differ from those estimates. Management determined that blended volatility, a combination of historical and implied volatility, is more reflective of market conditions and a better indicator of expected volatility than historical or implied volatility alone. The assumptions used in calculating the fair value of share-based payment awards represent management’s best estimates, but these estimates involve inherent uncertainties and the application of management judgment. As a result, if factors change and the Company uses different assumptions, its stock-based compensation expense could be materially different in the future. Accumulated Other Comprehensive Income For foreign subsidiaries where the functional currency is the local currency, assets and liabilities are translated into U.S. dollars at the current exchange rate on the balance sheet date. Revenue and expenses are translated at average rates of exchange prevailing during the year. Translation adjustments resulting from this process are recorded to Accumulated Other Comprehensive Income (“OCI”). Unrealized gains and losses on securities classified as available-for-sale Net Income Per Share Basic net income per share is based on the weighted average number of common shares outstanding, and diluted net income per share is based on the weighted average number of common shares outstanding and all potential dilutive common equivalent shares outstanding. The dilutive effect of options is determined under the treasury stock method using the average market price for the period. Common equivalent shares are included in the per share calculations when the effect of their inclusion would be dilutive. Cash and Cash Equivalents and Investments All highly liquid investments with a maturity date of three months or less at the date of purchase are considered to be cash equivalents. The appropriate classification of investments in securities is determined at the time of purchase. Debt securities that the Company does not have the intent and ability to hold to maturity are classified as “available-for-sale” The Company classifies investments with maturity dates greater than twelve months in short-term investments rather than long-term investments. This method classifies these securities as current based on the nature of the securities and the availability for use in current operations. The Company believes this method is preferable because it is more reflective of the Company’s assessment of its overall liquidity position. The Company reviews its investment portfolio on a quarterly basis to identify and evaluate individual investments that have indications of possible impairment. The factors considered in determining whether a loss is other-than-temporary include: the length of time and extent to which fair market value has been below the cost basis, the financial condition and near-term prospects of the issuer, credit quality, and the Company’s ability to hold the investment for a period of time sufficient to allow for any anticipated recovery in fair value. Concentrations of Credit Risk The Company’s significant concentrations of credit risk consist principally of cash and cash equivalents, investments, forward exchange contracts and trade accounts receivable. The Company maintains cash and cash equivalents with financial institutions including some banks with which it had borrowings. The Company maintains investments primarily in U.S. Treasury and government agency securities and corporate debt securities. The Company enters into forward currency contracts with high credit-quality financial institutions in order to minimize credit risk exposure. The Company’s largest customers are primarily concentrated in the semiconductor industry, and a limited number of these customers account for a significant portion of the Company’s revenues. The Company regularly monitors the creditworthiness of its customers and believes it has adequately provided for potential credit loss exposures. Credit is extended for all customers based primarily on financial condition, and collateral is not required. The Company had one customer, Applied Materials, Inc., comprising 13%, 14% and 18% of net revenues for 2017, 2016 and 2015, respectively, and another customer, Lam Research Corporation, comprising 12%, 11% and 13% of net revenues for 2017, 2016 and 2015, respectively. During the years 2017, 2016 and 2015, approximately 57%, 56% and 69% of the Company’s net revenues, respectively, were from sales to semiconductor capital equipment manufacturers and semiconductor device manufacturers. One customer, Applied Materials, Inc., represented 10% or more of the Company’s accounts receivable balance as of December 31, 2017. Inventories Inventories are stated at the lower of cost or market, cost being determined using a standard costing system which approximates cost based on a first-in, first-out Property, Plant and Equipment Property, plant and equipment are stated at cost. Expenditures for major renewals and betterments that extend the useful lives of property, plant and equipment are capitalized. Expenditures for maintenance and repairs are charged to expense as incurred. When assets are sold or otherwise disposed of, the cost and related accumulated depreciation are eliminated from the accounts and any resulting gain or loss is recognized in earnings. Depreciation is provided on the straight-line method over the estimated useful lives of twenty to thirty-one one-half Intangible Assets Intangible assets resulting from the acquisitions of businesses are estimated by management based on the fair value of assets acquired. These include acquired customer lists, technology, patents, trade names, covenants not to compete and IPR&D. Intangible assets are amortized from one to eighteen years on a straight-line basis which represents the estimated periods of benefit and the expected pattern of consumption. Goodwill Goodwill is the amount by which the cost of acquired net assets exceeded the fair value of those net assets on the date of acquisition. The Company allocates goodwill to reporting units at the time of acquisition or when there is a change in the reporting structure and bases that allocation on which reporting units will benefit from the acquired assets and liabilities. Reporting units are defined as operating segments or one level below an operating segment, referred to as a component. The Company assesses goodwill for impairment on an annual basis as of October 31 or more frequently when events and circumstances occur indicating that the recorded goodwill may be impaired. The estimated fair value of the Company’s reporting units are based on discounted cash flow models derived from internal earnings and internal and external market forecasts. Determining fair value requires the exercise of significant judgment, including judgments about appropriate discount rates, perpetual growth rates and the amount and timing of expected future cash flows. Discount rates are based on a weighted average cost of capital (“WACC”), which represents the average rate a business must pay its providers of debt and equity. The WACC used to test goodwill is derived from a group of comparable companies. Assumptions in estimating future cash flows are subject to a high degree of judgment and complexity. The Company makes every effort to forecast these future cash flows as accurately as possible with the information available at the time the forecast is developed. In performing the Company’s annual goodwill impairment test, the Company is permitted to first assess qualitative factors to determine whether it is more likely than not that the fair value of our reporting unit is less than its carrying amount, including goodwill. The qualitative assessment, is commonly referred to as “step zero.” In performing the qualitative step zero assessment, the Company considers certain events and circumstances specific to the reporting unit and to the entity as a whole, such as macroeconomic conditions, industry and market considerations, overall financial performance and cost factors when evaluating whether it is more likely than not that the fair value of the reporting unit is less than its carrying amount. The Company is also permitted to bypass the qualitative assessment and proceed directly to the quantitative test. If the Company chooses to undertake the qualitative assessment and concludes that it is more likely than not that the fair value of the reporting unit is less than its carrying amount, the Company would then proceed to the quantitative impairment test. In the quantitative assessment, the Company compares the fair value of the reporting unit to its carrying amount, which includes goodwill. If the fair value exceeds the carrying value, no impairment loss exists. If the fair value is less than the carrying amount, a goodwill impairment loss is measured and recorded. As of October 31, 2017, the Company performed its annual impairment assessment of goodwill using the qualitative step zero assessment and determined that it is more likely than not that the fair values of the reporting units exceed their carrying amount. Impairment of Long-Lived Assets The Company evaluates the recoverability of its long-lived assets whenever events and changes in circumstances indicate that the carrying amount of an asset may not be fully recoverable. This periodic review may result in an adjustment of estimated depreciable lives or asset impairment. When indicators of impairment are present, the carrying values of the asset are evaluated in relation to their operating performance and future undiscounted cash flows of the underlying business. If the future undiscounted cash flows are less than their carrying value, impairment exists. The impairment is measured as the difference between the carrying value and the fair value of the underlying asset. Fair values are based on estimates of market prices and assumptions concerning the amount and timing of estimated future cash flows and assumed discount rates, reflecting varying degrees of perceived risk. In 2017, the Company recorded an impairment charge of $6,719 related to certain long-lived assets as a result of consolidating two manufacturing plants. Foreign Exchange The functional currency of the majority of the Company’s foreign subsidiaries is the applicable local currency. For those subsidiaries, assets and liabilities are translated to U.S. dollars at year-end Net foreign exchange losses resulting from re-measurement re-measurement Income Taxes The Company records income taxes using the asset and liability method. Deferred income tax assets and liabilities are recognized for the future tax consequences attributable to differences between the financial statement carrying amounts of existing assets and liabilities and their respective income tax bases, and also for operating loss and tax credit carry-forwards. On a quarterly basis, the Company evaluates both the positive and negative evidence that affects the realizability of net deferred tax assets and assesses the need for a valuation allowance. The future benefit to be derived from its deferred tax assets is dependent upon its ability to generate sufficient future taxable income in each jurisdiction of the right type to realize the assets. The Company records a valuation allowance to reduce its net deferred tax assets to the amount that is more likely than not to be realized. To the extent the Company establishes a valuation allowance an expense will be recorded as a component of the provision for income taxes on the statement of operations. During 2015, the Company decreased its valuation allowance by $20,636 primarily related to the expiration of U.S. capital loss carry-forwards. As a result, the valuation allowance was $6,127 at December 31, 2015. During 2016, the Company increased its valuation allowance by $6,400 primarily related to the addition of historical valuation allowances for Newport and its subsidiaries which were included as a result of the acquisition in April 2016. As a result, the valuation allowance was $12,527 at December 31, 2016. During 2017, the Company increased its valuation allowance by $1,102, primarily related to certain state tax credits. As a result, the valuation allowance was $13,629 at December 31, 2017. Accounting for income taxes requires a two-step re-evaluates On December 22, 2017, the President of the United States signed into law the Tax Cuts and Jobs Act (the “Act”), which included significant changes to U.S. tax law. Some of the more significant changes impacting the Company are the reduction of the U.S. federal corporate income tax rate from 35.0% to 21.0% as of January 1, 2018, the implementation of a territorial tax system and the imposition of a transition tax on deemed repatriated cumulative earnings of foreign subsidiaries (“transition tax”). Income tax effects resulting from changes in tax are generally accounted for by the Company in the period in which the law is enacted and the effects are recorded as a component of provision for income taxes from continuing operations. On December 22, 2017, the Securities and Exchange Commission Staff issued Staff Accounting Bulletin No. 118 (“SAB 118”) to provide guidance for reporting entities’ ability to timely complete the accounting for certain income tax effects of the Act. In accordance with SAB 118, the Company has computed and reported reasonable estimates related to the transition tax and the revaluation of deferred tax assets and liabilities and included these provisional amounts in its consolidated financial statements for the year ended December 31, 2017. The estimates of the impacts of the Act on the Company are based on the Company’s current assumptions and understandings of the provisions of the Act. The ultimate impacts of the Act on the Company may differ from these provisional amounts due to additional analysis, changes in interpretations and assumptions by the Company and additional regulatory guidance that may be issued. The Company is required to finalize its estimate of the effects of the Act within a measurement period ending when the Company has obtained, prepared and analyzed the information needed to complete the accounting requirements under Accounting Standards Codification (“ASC”) Topic 740.

Recently Issued Accounting Pron

Recently Issued Accounting Pronouncements	12 Months Ended
	Dec. 31, 2017
Accounting Changes and Error Corrections [Abstract]
Recently Issued Accounting Pronouncements	4) Recently Issued Accounting Pronouncements In August 2017, the Financial Accounting Standards Board (“FASB”) issued Accounting Standards Update (“ASU”) 2017-12, In May 2017, the FASB issued ASU 2017-09, In March 2017, the FASB issued ASU 2017-07, In January 2017, the FASB issued ASU 2017-04, In January 2017, the FASB issued ASU 2017-01, In November 2016, the FASB issued ASU 2016-18, 2016-15. beginning-of-period end-of-period 2016-15. In October 2016, the FASB issued ASU 2016-16, In August 2016, the FASB issued ASU 2016-15, In February 2016, the FASB issued ASU 2016-02, In January 2016, the FASB issued ASU 2016-01, “Financial 825-10): In May 2014, the FASB issued ASU 2014-09, The FASB issued additional updates to the new revenue standard in Topic 606 relating to reporting revenue on a gross versus net basis (Update 2016-08 2016-10 2016-12 2016-20 2017-13 2017-14

Investments

Investments	12 Months Ended
	Dec. 31, 2017
Investments, Debt and Equity Securities [Abstract]
Investments	5) Investments Investments classified as short-term consist of the following: Years Ended December 31, Available-for-sale 2017 2016 Time deposits and certificates of deposit $ 9,757 $ 23,818 Bankers’ acceptance drafts 5,330 1,439 Asset-backed securities 36,990 36,809 Commercial paper 13,750 24,381 Corporate obligations 77,821 46,707 Municipal bonds 1,970 591 Promissory note — 675 U.S. treasury obligations 28,078 25,414 U.S. agency obligations 35,738 29,629 $ 209,434 $ 189,463 Investments classified as long-term consist of the following: Years Ended December 31, Available-for-sale 2017 2016 Group insurance contracts $ 6,255 $ 5,558 Cost method investments: Minority interest in a private company(1) 4,400 4,300 $ 10,655 $ 9,858 (1) In April of 2016 the Company invested $9,300 for a minority interest in a private company. During 2016, the Company recognized $5,000 of impairment charges related to this cost method investment. In July 2017, the Company invested an additional $100 in this private company. The following table shows the gross unrealized gains and (losses) aggregated by investment category for available-for-sale As of December 31, 2017: Cost Gross Gross Estimated Short-term investments: Available-for-sale Time deposits and certificates of deposit $ 9,756 $ 1 $ — $ 9,757 Bankers acceptance drafts 5,330 — — 5,330 Asset-backed securities 37,017 15 (42 ) 36,990 Commercial paper 13,810 — (60 ) 13,750 Corporate obligations 77,788 58 (25 ) 77,821 Municipal bonds 1,970 — — 1,970 U.S. treasury obligations 28,054 24 — 28,078 U.S. agency obligations 35,728 10 — 35,738 $ 209,453 $ 108 $ (127 ) $ 209,434 As of December 31, 2017: Cost Gross Gross Estimated Long-term investments: Available-for-sale Group insurance contracts $ 6,006 $ 249 $ — $ 6,255 As of December 31, 2016: Cost Gross Gross Estimated Short-term investments: Available-for-sale Time deposits and certificates of deposit $ 23,818 $ — $ — $ 23,818 Bankers acceptance drafts 1,439 — — 1,439 Asset-backed securities 36,847 6 (44 ) 36,809 Commercial paper 24,423 — (42 ) 24,381 Corporate obligations 46,700 21 (14 ) 46,707 Municipal bonds 591 — — 591 Promissory note 675 — — 675 U.S. treasury obligations 25,414 — — 25,414 U.S. agency obligations 29,631 8 (10 ) 29,629 $ 189,538 $ 35 $ (110 ) $ 189,463 As of December 31, 2016: Cost Gross Gross Estimated Long-term investments: Available-for-sale Group insurance contracts $ 5,432 $ 126 $ — $ 5,558 The tables above, which show the gross unrealized gains and (losses) aggregated by investment category for available-for-sale Interest income is accrued as earned. Dividend income is recognized as income on the date the stock trades “ex-dividend.”

Fair Value Measurements

Fair Value Measurements	12 Months Ended
	Dec. 31, 2017
Fair Value Disclosures [Abstract]
Fair Value Measurements	6) Fair Value Measurements In accordance with the provisions of fair value accounting, a fair value measurement assumes that the transaction to sell an asset or transfer a liability occurs in the principal market for the asset or liability or, in the absence of a principal market, the most advantageous market for the asset or liability and defines fair value based upon an exit price model. The fair value measurement guidance establishes a fair value hierarchy which requires an entity to maximize the use of observable inputs and minimize the use of unobservable inputs when measuring fair value. The guidance describes three levels of inputs that may be used to measure fair value: Level 1 Quoted prices in active markets for identical assets or liabilities as of the reporting date. Active markets are those in which transactions for the asset or liability occur in sufficient frequency and volume to provide pricing information on an ongoing basis. Level 2 Observable inputs other than Level 1 prices, such as quoted prices for similar assets or liabilities; quoted prices in markets that are not active; or other inputs that are observable or can be corroborated by observable market data for substantially the full term of the assets or liabilities. Level 2 assets and liabilities include debt securities with quoted prices that are traded less frequently than exchange-traded instruments or securities or derivative contracts that are valued using a pricing model with inputs that are observable in the market or can be derived principally from or corroborated by observable market data. Level 3 Unobservable inputs that are supported by little or no market activity and that are significant to the fair value of the assets or liabilities. Level 3 assets and liabilities include financial instruments whose value is determined using pricing models, discounted cash flow methodologies, or similar techniques, as well as instruments for which the determination of fair value requires significant management judgment or estimation. In certain cases, the inputs used to measure fair value may fall into different levels of the fair value hierarchy. In such cases, the Company categorizes such assets and liabilities based on the lowest level input that is significant to the fair value measurement in its entirety. The Company’s assessment of the significance of a particular input to the fair value measurement in its entirety requires judgment and considers factors specific to the asset. Assets and liabilities of the Company measured at fair value on a recurring basis as of December 31, 2017, are summarized as follows: Fair Value Measurements at Reporting Date Using Description December 31, Quoted Prices in (Level 1) Significant Other (Level 2) Significant (Level 3) Assets: Cash equivalents: Money market funds $ 4,987 $ 4,987 $ — $ — Time deposits and certificates of deposit 2,100 — 2,100 — Commercial paper 30,475 — 30,475 — Restricted cash – money market funds 119 119 — — Available-for-sale — Time deposits and certificates of deposit 9,757 — 9,757 — Bankers acceptance drafts 5,330 — 5,330 — Asset-backed securities 36,990 — 36,990 — Commercial paper 13,750 — 13,750 — Corporate obligations 77,821 — 77,821 — Municipal bonds 1,970 — 1,970 — U.S. treasury obligations 28,078 — 28,078 — U.S. agency obligations 35,738 — 35,738 — Group insurance contracts 6,255 — 6,255 — Derivatives – currency forward contracts 168 — 168 — Funds in investments and other assets: — Israeli pension assets 15,048 — 15,048 — Derivatives - interest rate hedge - non-current 6,179 — 6,179 — Restricted cash – non-current 1,010 1,010 — — Total assets $ 275,775 $ 6,116 $ 269,659 $ — Liabilities: Derivatives – currency forward contracts $ 6,198 $ — $ 6,198 $ — Reported as follows: Assets: Cash and cash equivalents(1) $ 37,562 $ 4,987 $ 32,575 $ — Restricted cash 119 119 — — Short-term investments 209,434 — 209,434 — Other current assets 168 — 168 — Total current assets $ 247,283 $ 5,106 $ 242,177 $ — Long-term investments(2) $ 6,255 $ — $ 6,255 $ — Other assets 22,237 1,010 21,227 — Total long-term assets $ 28,492 $ 1,010 $ 27,482 $ — Liabilities: Other current liabilities $ 6,198 $ — $ 6,198 $ — (1) The cash and cash equivalent amounts presented in the table above do not include cash of $292,808 and non-negotiable (2) The long-term investments presented in the table above do not include our minority interest investment in a private company, which is accounted for under the cost method. Assets and liabilities of the Company measured at fair value on a recurring basis as of December 31, 2016, are summarized as follows: Fair Value Measurements at Reporting Date Using Description December 31, Quoted Prices in (Level 1) Significant Other (Level 2) Significant (Level 3) Assets: Cash equivalents: Money market funds $ 10,155 $ 10,155 $ — $ — Time deposits and certificates of deposit 4,900 — 4,900 — Bankers acceptance drafts 448 — 448 — Commercial paper 11,828 — 11,828 — Corporate obligations 2,025 — 2,025 — U.S. agency obligations 3,899 — 3,899 — Restricted cash – money market funds 5,287 5,287 — — Available-for-sale Time deposits and certificates of deposit 23,818 — 23,818 — Bankers acceptance drafts 1,439 — 1,439 — Asset-backed securities 36,809 — 36,809 — Commercial paper 24,381 — 24,381 — Corporate obligations 46,707 — 46,707 — Municipal bonds 591 — 591 — Promissory note 675 — 675 — U.S. treasury obligations 25,414 — 25,414 — U.S. agency obligations 29,629 — 29,629 — Group insurance contracts 5,558 — 5,558 — Derivatives – currency forward contracts 2,985 — 2,985 — Derivatives – options contracts 4 — 4 — Funds in investments and other assets: Israeli pension assets 13,910 — 13,910 — Derivatives - interest rate hedge - non-current 4,900 — 4,900 — Restricted cash – non-current 573 573 — — Total assets $ 255,935 $ 16,015 $ 239,920 $ — Liabilities: Derivatives – currency forward contracts 543 — 543 — Derivatives – options contracts 16 — 16 — Total liabilities $ 559 $ — $ 559 $ — Reported as follows: Assets: Cash and cash equivalents(1) $ 33,255 $ 10,155 $ 23,100 $ — Restricted cash 5,287 5,287 — — Short-term investments 189,463 — 189,463 — Other current assets 2,989 — 2,989 — Total current assets $ 230,994 $ 15,442 $ 215,552 $ — Long-term investments(2) $ 5,558 $ — $ 5,558 $ — Other assets 19,383 573 18,810 — Total long-term assets $ 24,941 $ 573 $ 24,368 $ — Liabilities: Other current liabilities $ 559 $ — $ 559 $ — (1) The cash and cash equivalent amounts presented in the table above do not include cash of $192,432 and non-negotiable (2) The long-term investments presented in the table above do not include our minority interest investment in a private company, which is accounted for under the cost method. Money Market Funds Money market funds are cash and cash equivalents, and are classified within Level 1 of the fair value hierarchy. Restricted Cash The Company has letters of credit, which require it to maintain specified cash deposit balances, consisting mainly of money market funds, as collateral. Such amounts have been classified as restricted cash and are classified as Level 1. Available-For-Sale As of December 31, 2017, available-for-sale The Company measures its debt and equity investments at fair value. The Company’s available-for-sale Israeli Pension Assets Israeli pension assets represent investments in mutual funds, government securities and other time deposits. These investments are set aside for the retirement benefit of the employees at the Company’s Israeli subsidiaries. These funds are classified within Level 2 of the fair value hierarchy. Derivatives As a result of the Company’s global operating activities, the Company is exposed to market risks from changes in foreign currency exchange rates and variable interest rates, which may adversely affect its operating results and financial position. When deemed appropriate, the Company minimizes its risks from foreign currency exchange rate and interest rate fluctuations through the use of derivative financial instruments. The principal market in which the Company executes its foreign currency contracts and interest rate swaps is the institutional market in an over-the-counter

Derivatives

Derivatives	12 Months Ended
	Dec. 31, 2017
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Derivatives	7) Derivatives The Company enters into derivative instruments for risk management purposes only, including derivatives designated as hedging instruments and those utilized as economic hedges. The Company operates internationally and, in the normal course of business, is exposed to fluctuations in interest rates and foreign exchange rates. These fluctuations can increase the costs of financing, investing and operating the business. The Company has used derivative instruments, such as forward contracts, to manage certain foreign currency exposure, and interest rate swaps to manage interest rate exposure. By nature, all financial instruments involve market and credit risks. The Company enters into derivative instruments with major investment grade financial institutions, for which no collateral is required. The Company has policies to monitor the credit risk of these counterparties. While there can be no assurance, the Company does not anticipate any material non-performance Interest Rate Swap Agreement On September 30, 2016, the Company entered into an interest rate swap agreement to fix the rate on approximately 50% of its then outstanding term loan balance, as described further in Note 13. This hedge fixes the interest rate paid on the hedged debt at 1.198% per annum plus the credit spread, which was 2.00% as of December 31, 2017, through September 30, 2020. The interest rate swap will be recorded at fair value on the balance sheet and changes in the fair value will be recognized in OCI. To the extent that this arrangement is no longer an effective hedge, any ineffectiveness measured in the hedging relationship is recorded currently in earnings in the period it occurs. The notional amount of this transaction was $305,000 and had a fair value of $6,179 at December 31, 2017. The notional amount of this transaction was $335,000 and had a fair value of $4,900 at December 31, 2016. Foreign Exchange Contracts The Company hedges a portion of its forecasted foreign currency-denominated intercompany sales of inventory, over a maximum period of eighteen months, using forward foreign exchange contracts accounted for as cash-flow hedges related to Japanese, South Korean, British, Euro and Taiwanese currencies. To the extent these derivatives are effective in off-setting As of December 31, 2017 and 2016, the Company had outstanding forward foreign exchange contracts with gross notional values of $208,922 and $120,208, respectively. The following tables provide a summary of the primary net hedging positions and corresponding fair values held as of December 31, 2017 and 2016: December 31, 2017 Currency Hedged (Buy/Sell) Gross Notional Fair Value(1) U.S. Dollar/Japanese Yen $ 70,175 $ (233 ) U.S. Dollar/South Korean Won 79,672 (3,799 ) U.S. Dollar/Euro 26,140 (1,047 ) U.S. Dollar/U.K. Pound Sterling 12,104 (337 ) U.S. Dollar/Taiwan Dollar 20,831 (614 ) Total $ 208,922 $ (6,030 ) December 31, 2016 Currency Hedged (Buy/Sell) Gross Notional Fair Value(1) U.S. Dollar/Japanese Yen $ 30,522 $ 763 U.S. Dollar/South Korean Won 50,049 1,342 U.S. Dollar/Euro 18,040 156 U.S. Dollar/U.K. Pound Sterling 6,067 117 U.S. Dollar/Taiwan Dollar 15,530 64 Total $ 120,208 $ 2,442 (1) Represents the receivable (payable) amount included in the consolidated balance sheet. The following table provides a summary of the fair value amounts of the Company’s derivative instruments: Years Ended December 31, Derivatives Designated as Hedging Instruments 2017 2016 Derivative assets: Forward exchange contracts(1) $ 168 $ 2,985 Foreign currency interest rate hedge(2) 6,179 4,900 Derivative liabilities: Forward exchange contracts(1) (6,198 ) (543 ) Total net derivative asset designated as hedging instruments $ 149 $ 7,342 (1) The derivative asset of $168 and derivative liability of $(6,198) related to the forward foreign exchange contracts are classified in other current assets and other current liabilities in the consolidated balance sheet as of December 31, 2017. The derivative asset of $2,985 and derivative liability of $(543) are classified in other current assets and other current liabilities in the consolidated balance sheet as of December 31, 2016. These forward foreign exchange contracts are subject to a master netting agreement with one financial institution. However, the Company has elected to record these contracts on a gross basis in the balance sheet. (2) The foreign currency interest rate hedge asset of $6,179 and $4,900 is classified in other assets in the consolidated balance sheet as of December 31, 2017 and 2016, respectively. The net amount of existing gains as of December 31, 2017 that is expected to be reclassified from OCI into earnings within the next 12 months is immaterial. The following table provides a summary of the (losses) gains on derivatives designated as cash flow hedging instruments: Years Ended December 31, Derivatives Designated as Cash Flow Hedging Instruments 2017 2016 2015 Forward exchange contracts: Net (loss) gain recognized in OCI(1) $ (6,036 ) $ 5,914 $ (3,748 ) Net (loss) gain reclassified from OCI into income(2) $ (2,685 ) $ (1,414 ) $ 3,520 (1) Net change in the fair value of the effective portion classified in OCI. (2) Effective portion classified as cost of products in 2017, 2016 and 2015. The following table provides a summary of losses on derivatives not designated as cash flow hedging instruments: Years Ended December 31, Derivatives Not Designated as Hedging Instruments 2017 2016 2015 Forward exchange contracts: Net loss recognized in income(1) $ (3,416 ) $ (31 ) $ (40 ) (1) The Company enters into forward foreign exchange contracts to hedge against changes in the balance sheet for certain subsidiaries to mitigate the risk associated with certain foreign currency transactions in the ordinary course of business. These derivatives are not designated as cash flow hedging instruments and gains or losses from these derivatives are recorded immediately in other expense, net in 2017 and 2016 and in selling, general and administrative expenses in 2015.

Inventories

Inventories	12 Months Ended
	Feb. 22, 2018
Inventory Disclosure [Abstract]
Inventories	8) Inventories Inventories consist of the following: Years Ended December 31, 2017 2016 Raw material $ 191,351 $ 150,150 Work-in-process 54,050 39,105 Finished goods 93,680 86,614 $ 339,081 $ 275,869 Inventory-related excess and obsolete charges of $20,213, $16,039 and $13,602 were recorded in cost of products in the years ended December 31, 2017, 2016 and 2015, respectively.

Property, Plant and Equipment

Property, Plant and Equipment	12 Months Ended
	Feb. 22, 2018
Property, Plant and Equipment [Abstract]
Property, Plant and Equipment	9) Property, Plant and Equipment Property, plant and equipment consist of the following: Years Ended December 31, 2017 2016 Land $ 11,650 $ 11,115 Buildings 103,563 100,169 Machinery and equipment 317,073 297,342 Furniture and fixtures, office equipment and software 145,945 139,392 Leasehold improvements 65,293 63,431 Construction in progress 13,619 6,592 657,143 618,041 Less: accumulated depreciation 485,361 443,482 $ 171,782 $ 174,559 Depreciation of property, plant and equipment totaled $36,813, $30,245 and $15,339 for the years ended 2017, 2016 and 2015, respectively.

Acquisitions and Dispositions

Acquisitions and Dispositions	12 Months Ended
	Dec. 31, 2017
Business Combinations [Abstract]
Acquisitions and Dispositions	10) Acquisitions and Dispositions Newport Corporation On April 29, 2016, the Company completed its acquisition of Newport Corporation (“Newport”) pursuant to an Agreement and Plan of Merger, dated as of February 22, 2016 (the “Merger Agreement”), by and among the Company, PSI Equipment, Inc., a wholly owned subsidiary of the Company (“Merger Sub”), and Newport (the “Newport Merger”). At the effective time of the Newport Merger and pursuant to the terms and conditions of the Merger Agreement, each share of Newport’s common stock that was issued and outstanding immediately prior to the effective time of the Newport Merger was converted into the right to receive $23.00 in cash, without interest and subject to deduction for any required withholding tax. Newport’s innovative solutions leverage its expertise in advanced technologies, including lasers, photonics and precision motion equipment, and optical components and sub-systems, The purchase price of Newport consisted of the following: Cash paid for outstanding shares(1) $ 905,254 Settlement of share-based compensation awards(2) 8,824 Cash paid for Newport debt(3) 93,200 Total purchase price $ 1,007,278 Less: cash and cash equivalents acquired (61,463 ) Total purchase price, net of cash and cash equivalents acquired $ 945,815 (1) Represents cash paid of $23.00 per share for approximately 39,359,000 shares of Newport common stock, without interest and subject to a deduction for any required withholding tax. (2) Represents the vested but unissued portion of Newport share-based compensation awards as of the acquisition date of April 29, 2016. (3) Represents the cash paid for the outstanding balance of Newport’s senior secured revolving credit agreement. The Company funded the payment of the aggregate consideration with a combination of the Company’s available cash on hand and the proceeds from the Company’s senior secured term loan facility, as described in Note 13. Under the acquisition method of accounting, the total estimated acquisition consideration is allocated to the acquired tangible and intangible assets and assumed liabilities of Newport based on their fair values as of the acquisition date. Any excess of the acquisition consideration over the fair value of assets acquired and liabilities assumed is allocated to goodwill. Goodwill and intangible assets will not be amortizable for tax purposes. The following table summarizes the allocation of the purchase price to the fair values assigned to assets acquired and liabilities assumed at the date of the Newport Merger: Current assets (including cash) $ 186,137 Inventory 142,714 Intangible assets 404,506 Goodwill 396,027 Property, plant and equipment 119,932 Long-term assets 22,725 Total assets acquired 1,272,041 Current liabilities 95,156 Intangible liability 4,302 Other long-term liabilities 165,305 Total liabilities assumed 264,763 Fair value of assets acquired and liabilities assumed 1,007,278 Less: cash and cash equivalents acquired (61,463 ) Total purchase price, net of cash and cash equivalents acquired $ 945,815 The fair value write-up write-up The fair value write-up value-in-use, The acquired intangible assets are being amortized on a straight-line basis, which approximates the economic use of the asset. The following table reflects the allocation of the acquired intangible assets and liabilities and related estimate of useful lives: Order backlog $ 12,100 1 year Customer relationships 247,793 6-18 Trademarks and trade names 55,900 Indefinite Developed technology 75,386 4-8 In-process 6,899 Undefined (1) Leasehold interest (favorable) 6,428 4-5 Total intangible assets $ 404,506 Leasehold interest (unfavorable) $ 4,302 (1) The useful lives of in-process The fair value of the acquired intangibles was determined using the income approach. In performing these valuations, the key underlying probability-adjusted assumptions of the discounted cash flows were projected revenues, gross margin expectations and operating cost estimates. The valuations were based on the information that was available as of the acquisition date and the expectations and assumptions that have been deemed reasonable by the Company’s management. There are inherent uncertainties and management judgment required in these determinations. This acquisition resulted in a purchase price that exceeded the estimated fair value of tangible and intangible assets, the excess amount of which was allocated to goodwill. The Company believes the amount of goodwill relative to identifiable intangible assets relates to several factors including: (1) potential buyer-specific synergies related to market opportunities for a combined product offering; and (2) potential to leverage the Company’s sales force to attract new customers and revenue and cross sell to existing customers. The results of this acquisition were included in the Company’s consolidated operations beginning on April 29, 2016. Newport constitutes the Company’s Light & Motion reportable segment (Note 19). Certain executives from Newport had severance provisions in their respective Newport employment agreements. The agreements included terms that were accounted for as dual-trigger arrangements. Through the Company’s acquisition accounting, the expense relating to these benefits was recognized in the combined entity’s financial statements, however, the benefit itself will not be distributed until the final provision is met by each eligible executive. The Company recorded costs of $6,635 and $3,334 as compensation expense and stock-based compensation expense, respectively, during 2016 in connection with these severance provisions. The shares underlying the restricted stock units and stock appreciation rights that are eligible for accelerated vesting if the executive exercises his rights are not issued as of each reporting period-end Pro Forma Results The following unaudited pro forma financial information presents the combined results of operations of the Company as if the Newport Merger had occurred on January 1, 2015. The unaudited pro forma financial information is not necessarily indicative of what the Company’s condensed consolidated results of operations actually would have been had the acquisition occurred at the beginning of each year. In addition, the unaudited pro forma financial information does not attempt to project the future results of operations of the combined company. Years Ended December 31, 2016 2015 Total net revenues $ 1,475,637 $ 1,412,748 Net income 111,076 69,096 Net income per share: Basic $ 2.08 $ 1.30 Diluted $ 2.06 $ 1.29 The unaudited pro forma financial information above gives effect primarily to the following: (1) Incremental amortization and depreciation expense related to the estimated fair value of identifiable intangible assets and property, plant and equipment from the purchase price allocation. (2) Revenue adjustments as a result of the reduction in deferred revenue related to its estimated fair value. (3) Incremental interest expense related to the Company’s term loan credit agreement. (4) The exclusion of acquisition costs and inventory step-up (5) The estimated tax impact of the above adjustments. Cost Method Investment in a Private Company In April 2016, the Company invested $9,300 for a minority interest in a private company, which operates in the field of semiconductor process equipment instrumentation. The Company accounted for this investment using the cost method of accounting. During the fourth quarter of 2016, the Company recognized an impairment loss on this investment of $5,000 based upon financial information of this private company. In July 2017, the Company invested an additional $100 in this private company. Sale of Data Analytics Solutions In April 2017, the Company completed the sale of its Data Analytics Solutions business for total proceeds of $72,509, net of cash sold and recorded a gain of $74,856. This business, which had revenues in 2016 of $12,700 and was included in the Vacuum & Analysis segment, was no longer a part of the Company’s long-term strategic objectives. The business did not qualify as a discontinued operation as this sale did not represent a strategic shift in the Company’s business, nor did the sale have a major effect on the Company’s operations. Therefore, the results of operations for all periods are included in the Company’s income from operations. The assets and liabilities of this business have not been reclassified or segregated in the consolidated balance sheet or consolidated statements of cash flows as the amounts were immaterial. Precisive, LLC On March 17, 2015, the Company acquired Precisive, LLC (“Precisive”) for $12,085, net of cash acquired of $435. The purchase price included a deferred payment amount of $2,600 to cover any potential indemnification claims, which amount was paid to the sellers in the second quarter of 2016. Precisive is an innovative developer of optical analyzers based on Tunable Filter Spectroscopy, which provide real-time gas analysis in the natural gas and hydrocarbon processing industries, including refineries, hydrocarbon processing plants, gas-to-power The following table summarizes the estimated fair value of the assets acquired and liabilities assumed at the date of the Precisive acquisition: Current assets $ 693 Non-current 18 Intangible assets 5,110 Goodwill 7,042 Total assets acquired 12,863 Total current liabilities assumed 343 Fair value of asset acquired and liabilities assumed 12,520 Less: cash acquired (435 ) Total purchase price, net of cash acquired $ 12,085 Substantially all of the purchase price is deductible for tax purposes. The following table reflects the allocation of the acquired intangible assets and related estimates of useful lives. These acquired intangibles will be amortized on a straight-line basis, which approximates the pattern of use. Order backlog $ 50 18 months Customer relationships 1,430 8 years Exclusive patent license 2,600 10 years Trade names 210 10 years Developed technology 820 10 years Total intangible assets $ 5,110 The fair value of the acquired intangibles was determined using the income approach. The Precisive acquisition resulted in a purchase price that exceeded the estimated fair value of tangible and intangible assets, the excess amount of which was allocated to goodwill. The Company believes the amount of goodwill relative to identifiable intangible assets relates to several factors including: (1) potential buyer-specific synergies related to market opportunities for a combined product offering; (2) potential to leverage the Company’s sales force and intellectual property to attract new customers and revenue; and (3) potential to strengthen and expand into new but complementary markets, including targeting new applications such as natural gas processing, hydrocarbon processing and other oil and gas segments. The results of this acquisition were included in the Company’s consolidated operations beginning on March 17, 2015. Precisive is included in the Company’s Vacuum Solutions Products group within the Vacuum & Analysis segment.

Goodwill and Intangible Assets

Goodwill and Intangible Assets	12 Months Ended
	Dec. 31, 2017
Goodwill and Intangible Assets Disclosure [Abstract]
Goodwill and Intangible Assets	11) Goodwill and Intangible Assets Goodwill The Company’s methodology for allocating the purchase price relating to purchase acquisitions is determined through established and generally accepted valuation techniques. Goodwill is measured as the excess of the cost of the acquisition over the sum of the amounts assigned to tangible and identifiable intangible assets acquired less liabilities assumed. The Company assigns assets acquired (including goodwill) and liabilities assumed to one or more reporting units as of the date of acquisition. Typically acquisitions relate to a single reporting unit and thus do not require the allocation of goodwill to multiple reporting units. If the products obtained in an acquisition are assigned to multiple reporting units, the goodwill is distributed to the respective reporting units as part of the purchase price allocation process. Goodwill and purchased intangible assets with indefinite useful lives are not amortized, but are reviewed for impairment annually during the fourth quarter of each fiscal year and whenever events or changes in circumstances indicate that the carrying value of an asset may not be recoverable. The process of evaluating the potential impairment of goodwill and intangible assets requires significant judgment. The Company regularly monitors current business conditions and other factors including, but not limited to, adverse industry or economic trends, restructuring actions and lower projections of profitability that may impact future operating results. The changes in the carrying amount of goodwill and accumulated impairment losses were as follows: 2017 2016 Gross Accumulated Net Gross Accumulated Net Beginning balance at January 1 $ 727,999 $ (139,414 ) $ 588,585 $ 339,117 $ (139,414 ) $ 199,703 Acquired goodwill(1) — — — 396,027 — 396,027 Sale of business(2) (3,115 ) — (3,115 ) — — — Impairment loss(3) — (4,862 ) (4,862 ) — — — Foreign currency translation 10,439 — 10,439 (7,145 ) — (7,145 ) Ending balance at December 31 $ 735,323 $ (144,276 ) $ 591,047 $ 727,999 $ (139,414 ) $ 588,585 (1) During 2016, the Company recorded $396,027 of goodwill related to the Newport Merger. (2) In 2017, the Company sold its Data Analytics business and, as a result, charged the related goodwill of $3,115 to the gain on sale of business. (3) In 2017, the Company recorded an impairment loss of $4,862 related to the write-off Intangible Assets The Company is required to test certain long-lived assets when indicators of impairment are present. For the purposes of the impairment test, long-lived assets are grouped with other assets and liabilities at the lowest level for which identifiable cash flows are largely independent of the cash flows of other assets and liabilities. During 2017, the Company recorded impairment charges of $1,511 related to the write off of intangible assets as a result of the discontinuation of a product line and consolidation of two manufacturing plants. There were no intangible asset impairment charges in 2016 or 2015. Components of the Company’s acquired intangible assets are comprised of the following: As of December 31, 2017 Gross Impairment Accumulated Foreign Net Completed technology(1) $ 172,431 $ (105 ) $ (115,371 ) $ 333 $ 57,288 Customer relationships(1) 282,744 (1,406 ) (45,518 ) 1,571 237,391 Patents, trademarks, trade names and other(1) 110,523 — (38,730 ) (74 ) 71,719 $ 565,698 $ (1,511 ) $ (199,619 ) $ 1,830 $ 366,398 As of December 31, 2016 Gross Impairment Accumulated Foreign Net Completed technology(2) $ 176,586 $ — $ (97,707 ) $ (1,068 ) $ 77,811 Customer relationships(2) 285,044 — (29,709 ) (3,404 ) 251,931 Patents, trademarks, trade names and other(2) 111,723 — (33,397 ) (64 ) 78,262 $ 573,353 $ — $ (160,813 ) $ (4,536 ) $ 408,004 (1) In 2017, the Company sold its Data Analytics business and, as a result, wrote off the related intangibles of $4,155 of completed technology, $2,300 of customer relationships and $1,200 of patents, trademarks, trade names and other, which were fully amortized at the time of sale. (2) During 2016, the Company recorded $404,506 of separately identified intangible assets related to the Newport Merger, of which $75,386 was completed technology, $247,793 was customer relationships and $81,327 was patents, trademarks, trade names, in-process Aggregate amortization expense related to acquired intangible assets for the years 2017, 2016 and 2015 was $45,743, $35,681 and $6,764, respectively. The amortization expense in 2017 and 2016 is net of $811 and $569, respectively, of amortization income from unfavorable lease commitments. Aggregate net amortization expense related to acquired intangible assets and unfavorable lease commitments for future years is: Year Amount 2018 $ 43,404 2019 40,333 2020 28,262 2021 20,464 2022 17,703 Thereafter 157,360

Product Warranties

Product Warranties	12 Months Ended
	Dec. 31, 2017
Guarantees and Product Warranties [Abstract]
Product Warranties	12) Product Warranties The Company provides for the estimated costs to fulfill customer warranty obligations upon the recognition of the related revenue. While the Company engages in extensive product quality programs and processes, including actively monitoring and evaluating the quality of its component suppliers, the Company’s warranty obligation is affected by shipment volume, product failure rates, utilization levels, material usage and supplier warranties on parts delivered to the Company. Should actual product failure rates, utilization levels, material usage, or supplier warranties on parts differ from the Company’s estimates, revisions to the estimated warranty liability would be required. Product warranty activities were as follows: Years Ended December 31, 2017 2016 Beginning balance $ 8,261 $ 5,205 Product warranty liability from Newport Merger — 3,040 Provisions for product warranties 15,884 8,858 Direct and other charges to warranty liability (14,041 ) (8,842 ) Ending balance(1) $ 10,104 $ 8,261 (1) Short-term product warranty of $9,719 and long-term product warranty of $385, each as of December 31, 2017, are included within other current liabilities and other liabilities, respectively, within the accompanying consolidated balance sheet. Short-term product warranty of $8,200 and long-term product warranty of $61 as of December 31, 2016, are included within other current liabilities and other liabilities, respectively, within the accompanying consolidated balance sheet.

Debt

Debt	12 Months Ended
	Dec. 31, 2017
Debt Disclosure [Abstract]
Debt	13) Debt Term Loan Credit Agreement In connection with the completion of the Newport Merger, the Company entered into a term loan credit agreement (the “Credit Agreement”) with Barclays Bank PLC, as administrative agent and collateral agent, and the lenders from time to time party thereto (the “Lenders”), that provided senior secured financing of $780,000, subject to increase at the Company’s option in accordance with the Credit Agreement (the “Term Loan Facility”). Borrowings under the Term Loan Facility bear interest per annum at one of the following rates selected by the Company: (a) a base rate determined by reference to the highest of (1) the federal funds effective rate plus 0.50%, (2) the “prime rate” quoted in The Wall Street Journal, (3) a LIBOR rate determined by reference to the costs of funds for U.S. dollar deposits for an interest period of one month adjusted for certain additional costs, plus 1.00%, and (4) a floor of 1.75%, plus, in each case, an applicable margin based on the Company’s leverage ratio (1.25% as of December 31, 2017); or (b) a LIBOR rate determined by reference to the costs of funds for U.S. dollar deposits for the interest period relevant to such borrowing adjusted for certain additional costs, subject to a LIBOR rate floor of 0.75%, plus an applicable margin based on our leverage ratio (2.00% as of December 31, 2017). The Company has elected the interest rate as described in clause (b). The Credit Agreement provides that all loans will be determined by reference to the Base Rate if the LIBOR rate cannot be ascertained, if regulators impose material restrictions on the authority of a lender to make LIBOR rate loans, and for other reasons. The Term Loan Facility was issued with original issue discount of 1.00% of the principal amount thereof. On June 9, 2016, the Company entered into Amendment No. 1 (the “Re-pricing Re-pricing pre-payment “Re-pricing Re-pricing Re-pricing pre-payment Re-pricing On September 30, 2016, the Company entered into an interest rate swap agreement, which has a maturity date of September 30, 2020, to fix the rate on $335,000 of the then-outstanding balance of the Credit Agreement. The rate is fixed at 1.198% per annum plus the applicable credit spread, which was 2.00% at December 31, 2017. At December 31, 2017, the notional amount of the interest rate swap agreement was $305,000. On December 14, 2016, the Company entered into Amendment No. 2 (the “Re-pricing Re-pricing pre-payment Re-pricing Re-pricing Re-pricing On July 6, 2017, the Company entered into Amendment No. 3 (the “Re-pricing Re-pricing Re-pricing Re-pricing In July 2017, August 2017 and November 2017, the Company voluntarily prepaid $50,000, $75,000, and $50,000, respectively, of principal under the Credit Agreement. As of December 31, 2017, after total principal pre-payments The Company incurred $28,747 of deferred finance fees, original issue discount and re-pricing pre-payments re-pricing Under the Credit Agreement, the Company is required to prepay outstanding term loans, subject to certain exceptions, with portions of its annual excess cash flow as well as with the net cash proceeds of certain asset sales, certain casualty and condemnation events and the incurrence or issuance of certain debt. The Company is also required to make scheduled quarterly payments each equal to 0.25% of the principal amount of the term loans outstanding, less the amount of certain voluntary and mandatory repayments after such date, with the balance due on the seventh anniversary of the closing date. As a result of making total pre-payments All obligations under the Term Loan Facility are guaranteed by certain of the Company’s domestic subsidiaries, and are collateralized by substantially all of the Company’s assets and the assets of such subsidiaries, subject to certain exceptions and exclusions. The Credit Agreement contains customary representations and warranties, affirmative and negative covenants and provisions relating to events of default. If an event of default occurs, the Lenders under the Term Loan Facility will be entitled to take various actions, including the acceleration of amounts due under the Term Loan Facility and all actions generally permitted to be taken by a secured creditor. At December 31, 2017, the Company was in compliance with all covenants under the Credit Agreement. Senior Secured Asset-Based Revolving Credit Facility In connection with the completion of the Newport Merger, the Company also entered into an asset-based credit agreement with Deutsche Bank AG New York Branch, as administrative agent and collateral agent, the other borrowers from time to time party thereto, and the lenders and letters of credit issuers from time to time party thereto (the “ABL Facility”), that provides senior secured financing of up to $50,000, subject to a borrowing base limitation. The borrowing base for the ABL Facility at any time equals the sum of: (a) 85% of certain eligible accounts; plus (b) subject to certain notice and field examination and appraisal requirements, the lesser of (i) the lesser of (A) 65% of the lower of cost or market value of certain eligible inventory and (B) 85% of the net orderly liquidation value of certain eligible inventory and (ii) 30% of the borrowing base; minus (c) reserves established by the administrative agent; provided that until the administrative agent’s receipt of a field examination of accounts receivable the borrowing base shall be equal to 70% of the book value of certain eligible accounts. The ABL Facility includes borrowing capacity in the form of letters of credit up to $15,000. The Company has not drawn against the ABL Facility as of December 31, 2017. Borrowings under the ABL Facility bear interest per annum at one of the following rates selected by the Company: (a) a base rate determined by reference to the highest of (1) the federal funds effective rate plus 0.50%, (2) the “prime rate” quoted in The Wall Street Journal, and (3) a LIBOR rate determined by reference to the costs of funds for U.S. dollar deposits for an interest period of one month adjusted for certain additional costs, plus 1.00%, plus, in each case, an initial applicable margin of 0.75%; and (b) a LIBOR rate determined by reference to the costs of funds for U.S. dollar deposits for the interest period relevant to such borrowing adjusted for certain additional costs, plus an initial applicable margin of 1.75%. Commencing with the completion of the first fiscal quarter ending after the closing of the ABL Facility, the applicable margin for borrowings thereunder is subject to upward or downward adjustment each fiscal quarter, based on the average historical excess availability during the preceding quarter. The Company incurred $1,201 of costs in connection with the ABL Facility, which were capitalized and included in other assets in the accompanying consolidated balance sheets and are being amortized to interest expense using the straight-line method over the contractual term of five years of the ABL Facility. In addition to paying interest on outstanding principal under the ABL Facility, the Company is required to pay a commitment fee in respect of the unutilized commitments thereunder. The initial commitment fee is 0.375% per annum. The total commitment fee recognized in interest expense for the twelve months ended December 31, 2017 was $242. Commencing with the completion of the first fiscal quarter ending after the closing of the ABL Facility, the commitment fee is subject to downward adjustment based on the amount of average unutilized commitments for the three month period immediately preceding such adjustment date. The Company must also pay customary letter of credit fees and agency fees. Lines of Credit and Short-Term Borrowing Arrangements One of the Company’s Japanese subsidiaries has lines of credit and short-term borrowing arrangements with two financial institutions, which arrangements generally expire and are renewed at three month intervals. The lines of credit provided for aggregate borrowings as of December 31, 2017 of up to an equivalent of $20,410 U.S. dollars. One of the borrowing arrangements has an interest rate based on the Tokyo Interbank Offer Rate at the time of borrowing and the other has an interest rate based on the Japanese Short-Term Prime Lending Rate. There were no borrowings outstanding under these arrangements at December 31, 2017 and December 31, 2016. The Company assumed various revolving lines of credit and a financing facility with the completion of the Newport Merger. These revolving lines of credit and financing facility have no expiration date and provided for aggregate borrowings as of December 31, 2017 of up to an equivalent of $11,092 U.S. dollars. These lines of credit have a base interest rate of 1.25% plus a Japanese Yen overnight LIBOR rate. Total borrowings outstanding under these arrangements were $2,965 and $4,703 at December 31, 2017 and 2016. One of the Company’s Austrian subsidiaries has various outstanding loans from the Austrian government to fund research and development. These loans are unsecured and do not require principal repayment as long as certain conditions are met. Interest on these loans is payable semi-annually. The interest rates associated with these loans range from 0.75%—2.00%. Short-term debt: December 31, 2017 December 31, 2016 Japanese lines of credit $ 2,750 $ 4,245 Japanese receivables financing facility 215 458 Other debt 7 8 Current portion of Term Loan Facility — 6,282 $ 2,972 $ 10,993 Long-term debt: December 31, 2017 December 31, 2016 Austrian loans due through March 2020 $ 714 $ 548 Term Loan Facility, net(1) 389,279 600,681 $ 389,993 $ 601,229 (1) Net of deferred financing fees, original issuance discount and re-pricing The Company recognized interest expense of $30,990 and $30,611 for the twelve months ended December 31, 2017 and 2016, respectively. Contractual maturities of the Company’s debt obligations as of December 31, 2017 are as follows: Year Amount 2018 $ 2,972 2019 639 2020 75 2021 — 2022 — Thereafter 398,464

Income Taxes

Income Taxes	12 Months Ended
	Dec. 31, 2017
Income Tax Disclosure [Abstract]
Income Taxes	14) Income Taxes As of December 31, 2017, the Company had not fully completed its accounting for the tax effects of the enactment of the Act. The Company has recognized the provisional tax impacts related to the transition tax and the revaluation of deferred tax assets and liabilities and included these amounts in its consolidated financial statements for the year ended December 31, 2017 in accordance with the guidance provided in SAB 118. The Company has not yet completed sufficiently detailed calculations of the post-1986 foreign earnings and profits and the income tax pools for all foreign subsidiaries. In addition, the Company has identified items that require additional guidance from the Internal Revenue Service regarding certain aspects of tax computations required by the Act. The estimates of the impacts of the Act on the Company are based on the Company’s current assumptions and understanding of the provisions of the Act. The ultimate impacts of the Act on the Company may differ from these provisional amounts due to additional analysis, changes in interpretations and assumptions the Company has made and additional regulatory guidance that may be issued. SAB 118 also requires certain specific additional disclosures as follows: • Provisional amounts were reported for the transition tax and the revaluation of deferred taxes as a result of the statutory rate change and other factors. • The provisional amount recorded for the transition tax impacts current and long-term income taxes payable. The provisional amount recorded to revalue deferred taxes impacts long-term deferred tax assets and liabilities. • The Company needs to complete a detailed analysis of undistributed cumulative earnings and profits and foreign tax pools of its foreign subsidiaries and receive additional guidance from the Internal Revenue Service in order to complete the accounting requirements under ASC topic 740 for the provisional amounts. A reconciliation of the Company’s effective tax rate to the U.S. federal statutory rate is as follows: Years Ended December 31, 2017 2016 2015 U.S. Federal income tax statutory rate 35.0 % 35.0 % 35.0 % Federal tax credits (0.7 ) (1.8 ) (1.2 ) State income taxes, net of federal benefit 1.0 0.8 1.3 Effect of foreign operations taxed at various rates (12.1 ) (12.7 ) (6.4 ) Qualified production activity tax benefit (1.4 ) (2.9 ) (1.6 ) Transition tax, net of foreign tax credits 6.4 — — Revaluation of US deferred income taxes (5.0 ) — — Stock based compensation (2.5 ) — — Deferred tax asset valuation allowance (0.1 ) 2.1 — Release of income tax reserves (including interest) (0.4 ) (2.4 ) (4.8 ) Foreign dividends, net of foreign tax credits 3.3 (2.2 ) 0.7 Acquisition and integration related costs — 1.5 — Other 0.7 0.7 0.3 24.2 % 18.1 % 23.3 % The components of income from operations before income taxes and the related provision for income taxes consist of the following: Years Ended December 31, 2017 2016 2015 Income from operations before income taxes: United States $ 224,979 $ 42,491 $ 90,401 Foreign 222,646 85,486 69,067 $ 447,625 $ 127,977 $ 159,468 Current taxes: United States $ 77,023 $ 17,693 $ 15,813 State 6,149 2,359 2,927 Foreign 30,152 41,938 18,021 113,324 61,990 36,761 Deferred taxes: United States (16,250 ) (23,604 ) (862 ) State and Foreign 11,419 (15,218 ) 1,272 (4,831 ) (38,822 ) 410 Provision for income taxes $ 108,493 $ 23,168 $ 37,171 The significant components of the deferred tax assets and deferred tax liabilities are as follows: Years Ended December 31, 2017 2016 Deferred tax assets: Carry-forward losses and credits $ 25,834 $ 50,673 Inventory and warranty reserves 17,734 24,253 Accrued expenses and other reserves 15,393 16,176 Stock-based compensation 5,092 8,995 Executive supplemental retirement benefits 4,984 6,888 Other 597 — Total deferred tax assets $ 69,634 $ 106,985 Deferred tax liabilities: Acquired intangible assets (83,092 ) (127,571 ) Depreciation and amortization (10,150 ) (16,428 ) Loan costs (2,157 ) (7,282 ) Foreign withholding taxes (16,206 ) — Unrealized gain (469 ) (3,195 ) Other — (1,336 ) Total deferred tax liabilities (112,074 ) (155,812 ) Valuation allowance (13,629 ) (12,527 ) Net deferred tax (liabilities) assets $ (56,069 ) $ (61,354 ) As of December 31, 2017, a provisional adjustment reducing the net deferred tax liabilities of the Company was made in the amount of $22,345 due to the U.S. tax rate reduction as a result of the enactment of the Act and other related factors. As of December 31, 2017, the Company had federal, state and foreign gross research and other tax credit carry-forwards of $36,496. Included in the total carry-forward are $12,559 of credits that can be carried forward indefinitely and the remaining credits expire at various dates through 2035. The Company also had, state and foreign gross net operating loss carry-forwards of $43,431. Included in the total carry-forward are $37,098 of losses that can be carried forward indefinitely while the remaining losses expire at various dates through 2035. Although the Company believes that its tax positions are consistent with applicable U.S. federal, state and international laws, it maintains certain tax reserves as of December 31, 2017 in the event its tax positions were to be challenged by the applicable tax authority and additional tax assessed on audit. A reconciliation of the beginning and ending amount of gross unrecognized tax benefits is as follows: Years Ended December 31, 2017 2016 2015 Balance at beginning of year $ 25,465 $ 4,332 $ 19,610 Increases/(decreases) for prior years 640 (195 ) (26 ) Increases for the current year 4,340 23,940 322 Reductions related to settlements with taxing authorities — — (15,370 ) Reductions related to expiration of statute of limitations (3,100 ) (2,612 ) (204 ) Balance at end of year $ 27,345 $ 25,465 $ 4,332 As of December 31, 2017, the total amount of gross unrecognized tax benefits, which excludes interest and penalties, was $27,345. As of December 31, 2016, the total amount of gross unrecognized tax benefits, which excludes interest and penalties, was $25,465. The net increase from December 31, 2016 was primarily attributable to the addition of reserves related to foreign withholding tax and certain state tax credits. As of December 31, 2017, excluding interest and penalties, there are $18,276 of net unrecognized tax benefits that, if recognized, would impact the Company’s annual effective tax rate. In 2017, the Company recorded a net benefit to income tax expense of $3,100, excluding interest and penalties, due to the release of income tax reserves related to the expiration of certain statutes of limitation. The Company accrues interest and, if applicable, penalties for any uncertain tax positions. Interest and penalties are classified as a component of income tax expense. As of December 31, 2017, 2016 and 2015, the Company had accrued interest on unrecognized tax benefits of approximately $327, $491 and $157, respectively. Over the next 12 months it is reasonably possible that the Company may recognize approximately $1,025 of previously net unrecognized tax benefits, excluding interest and penalties, related to federal, state and foreign tax positions as a result of the expiration of statutes of limitation. The U.S. statute of limitations remains open for tax years 2014 through present. The statute of limitations for the Company’s tax filings in other jurisdictions varies between fiscal years 2012 through the present. The Company also has certain federal credit carry-forwards and state tax loss and credit carry-forwards that are open to examination for tax years 2000 through the present. The Company is subject to examination by U.S. federal, state and foreign tax authorities. The U.S. Internal Revenue Service commenced an examination of the Company’s U.S. federal income tax filings for tax years 2015 and 2016 during the quarter ended September 30, 2017. A previous audit by the U.S. Internal Revenue Service was effectively settled during the quarter ended December 31, 2015 upon the Company’s acceptance of the income tax examination changes. On a quarterly basis, the Company evaluates both positive and negative evidence that affects the realizability of net deferred tax assets and assesses the need for a valuation allowance. The future benefit to be derived from its deferred tax assets is dependent upon its ability to generate sufficient future taxable income to realize the assets. During 2017, the Company increased its valuation allowance by $1,102, primarily related to certain state tax credits. During 2016, the Company increased its valuation allowance by $6,400 primarily related to the addition of historical valuation allowances for Newport and its subsidiaries which were included as a result of the acquisition in April 2016. During 2015, the Company decreased its valuation allowance by $20,636, primarily related to the expiration of U.S. capital loss carry-forwards. The Act, provided for a one-time No provision has been made for the deferred taxes related to certain remaining historical outside basis differences in the Company’s non-U.S. The Company’s Israeli subsidiaries have elected to be treated under a preferential Israeli tax regime under which their taxable income is taxed at reduced tax rates. These reduced rates range anywhere between 7.5% and 16%. One of the Company’s Israeli subsidiaries effectively settled an examination for tax years 2012 and 2013 during the quarter ended June 30, 2017.

Stockholders' Equity

Stockholders' Equity	12 Months Ended
	Dec. 31, 2017
Equity [Abstract]
Stockholders' Equity	15) Stockholders’ Equity Stock Repurchase Program On July 25, 2011, the Company’s board of directors approved a share repurchase program for the repurchase of up to an aggregate of $200,000 of its outstanding common stock from time to time in open market purchases, privately negotiated transactions or through other appropriate means. The timing and quantity of any shares repurchased will depend upon a variety of factors, including business conditions, stock market conditions and business development activities, including, but not limited to, merger and acquisition opportunities. These repurchases may be commenced, suspended or discontinued at any time without prior notice. The Company has repurchased approximately 1,770,000 shares of common stock for approximately $52,000 pursuant to the program since its adoption. During 2017, there were no repurchases of common stock. During 2016, the Company repurchased 44,798 shares of its common stock for $1,545 at an average price of $34.50 per share. Cash Dividends Holders of the Company’s common stock are entitled to receive dividends when and if they are declared by the Company’s board of directors. The Company’s board of directors declared a cash dividend of $0.175 per share during the first, second and third quarters of 2017, and $0.18 per share during the fourth quarter of 2017, which totaled $38,178. During 2016, the Company’s board of directors declared a cash dividend of $0.17 per share during the first, second, third and fourth quarters, which totaled $36,361. Future dividend declarations, if any, as well as the record and payment dates for such dividends, are subject to the final determination of the Company’s board of directors. On February 12, 2018, the Company’s board of directors declared a quarterly cash dividend of $0.18 per share to be paid on March 9, 2018 to shareholders of record as of February 26, 2018.

Stock-Based Compensation

Stock-Based Compensation	12 Months Ended
	Dec. 31, 2017
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Stock-Based Compensation	16) Stock-Based Compensation Employee Stock Purchase Plans The 2014 ESPP Plan was adopted by the Board of Directors on February 10, 2014 and approved by the Company’s stockholders on May 5, 2014. The 2014 ESPP Plan authorizes the issuance of up to an aggregate of 2,500,000 shares of common stock to participating employees. Offerings under the 2014 ESPP Plan commence on June 1 and December 1 and terminate, respectively, on November 30 and May 31. Historically, under the 2014 ESPP Plan, eligible employees could purchase shares of common stock through payroll deductions of up to 10% of their compensation or up to an annual maximum amount of $21,250. The price at which an employee’s purchase option was exercised for each offering period was the lower of (1) 85% of the closing price of the common stock on the NASDAQ Global Select Market on the day that each offering commences, or (2) 85% of the closing price on the day that the offering terminated. On January 31, 2017, the Compensation Committee of the Board of Directors approved an increase in the exercise price to the lower of (1) 90% of the closing price of the common stock on the NASDAQ Global Select Market on the day that each offering commences, or (2) 90% of the closing price on the day that each offering terminates. The increase in the exercise price became effective for the Offering commencing on June 1, 2017. As a result of this change, the annual maximum payroll deduction was increased from $21,250 to $22,500. During 2017, 2016, and 2015, the Company issued 105,506, 139,079, and 140,531 shares, respectively, of common stock to employees who participated in the 2014 ESPP Plan at exercise prices of $46.37 and $74.12 per share in 2017, $31.40 and $35.16 per share in 2016, and $30.74 and $31.34 per share in 2015. As of December 31, 2017, there were 2,032,403 shares reserved for future issuance under the 2014 ESPP Plan. Equity Incentive Plans The Company has granted RSUs to employees and directors under the 2014 Stock Incentive Plan (the “2014 Plan”). The 2014 Plan is administered by the Compensation Committee of the Company’s Board of Directors. The 2014 Plan is intended to attract and retain employees and directors, and to provide an incentive for these individuals to assist the Company to achieve long-range performance goals and to enable these individuals to participate in the long-term growth of the Company. The 2014 Plan was adopted by the Board of Directors on February 10, 2014 and was approved by the Company’s stockholders on May 5, 2014. Up to 18,000,000 shares of common stock (subject to adjustment in the event of stock splits and other similar events) may be issued pursuant to awards granted under the 2014 Plan. The Company may grant options, RSUs, restricted stock, stock appreciation rights (“SARs”) and other stock-based awards to employees, officers, directors, consultants and advisors under the 2014 Plan. Any full-value awards granted under the 2014 Plan will be counted against the shares reserved for issuance under the 2014 Plan as 2.4 shares for each share of common stock subject to such award and any award granted under the 2014 Plan that is not a full-value award (including, without limitation, any option or SAR) will be counted against the shares reserved for issuance under the plan as one share for each one share of common stock subject to such award. “Full-value award” means any RSU, or other stock-based award with a per share price or per unit purchase price lower than 100% of fair market value on the date of grant. To the extent a share that was subject to an award that counted as one share is returned to the 2014 Plan, each applicable share reserve will be credited with one share. To the extent that a share that was subject to an award that counts as 2.4 shares is returned to the 2014 Plan, each applicable share reserve will be credited with 2.4 shares. As of December 31, 2017, there were 14,548,013 shares reserved for future issuance under the 2014 Plan. The Company’s 2004 Stock Incentive Plan (the “2004 Plan”) expired in March 2014 and no further awards may be granted under the 2004 Plan, although there are still outstanding RSUs which may vest under the 2004 Plan. The Company’s Second Restated 1995 Stock Incentive Plan (the “1995 Plan”) expired in November 2005 and no further awards may be granted under the 1995 Plan. The Company’s 1997 Director Stock Plan expired in February 2007 and no further awards may be granted under the 1997 Director Stock Plan. The 2004 Plan, the 1995 Plan, the 1997 Director Stock Plan and the 2014 Plan are referred to herein as the “Plans.” Stock options were granted at an exercise price equal to 100% of the fair value of the Company’s common stock on the date of grant. Generally, stock options granted to employees under the 1995 Plan and the 2004 Plan from 2001 to 2006, vested 25% after one year and 6.25% per quarter thereafter, and expired 10 years after the grant date. Options granted to directors generally vested at the earliest of (1) one day prior to the next annual meeting, (2) 13 months from the date of grant, or (3) the effective date of an acquisition. There were no remaining outstanding stock options as of December 31, 2017 and 2016, respectively under any of the Plans. RSUs granted to employees in 2017, 2016 and 2015 generally vest 33% per year on the anniversary of the date of grant. RSUs granted to certain employees who are at least 60 years old and have a minimum of 10 Years of Service (as defined in the applicable RSU agreement) are expensed immediately. RSUs granted to directors generally vest at the earliest of (1) one day prior to the next annual meeting, (2) 13 months from date of grant, or (3) the effective date of a change in control of the Company. Certain RSUs are subject to performance conditions (“performance shares”) under the Company’s 2004 Plan and 2014 Plan. Such performance shares are available, subject to time-based vesting conditions, if, and to the extent that, financial or operational performance criteria for the applicable period are achieved. Accordingly, the number of performance shares earned will vary based on the level of achievement of financial or operational performance objectives for the applicable period. In connection with the completion of the Newport Merger, the Company assumed: • all RSUs granted under any Newport equity plan that were outstanding immediately prior to the effective time of the Newport Merger, and as to which shares of Newport common stock were not fully distributed in connection with the closing of the Newport Merger, and • all stock appreciation rights granted under any Newport equity plan, whether vested or unvested, that were outstanding immediately prior to the effective time of the Newport Merger. As of the effective time of the Newport Merger, based on a formula provided in the Merger Agreement, (a) the Newport RSUs were converted automatically into RSUs with respect to 360,674 shares of the Company’s common stock (the “Assumed RSUs”), and (b) the Newport stock appreciation rights were converted automatically into SARs with respect to 899,851 shares of the Company’s common stock (the “Assumed SARs”). Included in the total number of Assumed RSUs were 36,599 RSUs for outside directors that were part of the Newport Deferred Compensation Plan (the “DC Plan”), from which 19,137 underlying shares were released in May 2016, and 5,515 shares were released in May 2017. As of December 31, 2017, 12,134 Company RSUs remained outstanding under the DC Plan, and an additional 122 shares of the Company’s common stock were added to the DC Plan due to reinvested dividends. As of December 31, 2016, 17,462 Company RSUs remained outstanding under the DC Plan, and an additional 187 shares of the Company’s common stock were added to the DC Plan due to reinvested dividends. These Assumed RSUs will not become issued shares until their respective release dates. The shares of the Company’s common stock that are subject to the Assumed SARs and the Assumed RSUs are issuable pursuant to the Company’s 2014 Plan. The 1,260,525 shares of the Company’s common stock that are issuable pursuant to the Assumed RSUs and the Assumed SARs under the 2014 Plan were registered under the Securities Act of 1933, as amended (“Securities Act”), on a registration statement on Form S-8. S-8. The following table presents the activity for RSUs under the Plans: Year Ended December 31, 2017 Non-vested RSUs Weighted Non-vested 1,325,516 $ 34.38 Accrued dividend shares Granted 122 389,610 78.34 67.69 Vested (684,967 ) 34.58 Forfeited or expired (86,902 ) 38.97 Non-vested 943,379 $ 47.57 The following table presents the activity for SARs under the Plans: Year Ended December 31, 2017 Non-vested SARs Weighted SARs — beginning of period 599,334 $ 28.10 Exercised (289,822 ) 27.60 Forfeited or expired (26,605 ) 28.07 SARs Outstanding — end of period 282,907 $ 28.62 At December 31, 2017, the Company’s outstanding and exercisable SARs, the weighted-average base value, the weighted average remaining contractual life and the aggregate intrinsic value thereof, were as follows: Number Weighted Average Weighted Average Aggregate Intrinsic SARs outstanding 282,907 $ 28.62 3.3 $ 18,639 SARs exercisable 221,375 $ 27.92 3.0 $ 14,740 The total cash received from employees as a result of employee stock option exercises during 2015 was approximately $592. In connection with these exercises, the tax benefit realized by the Company in 2015 was approximately $21. There were no options outstanding or exercisable under the Plans at December 31, 2017 and 2016, respectively. The Company settles employee stock option exercises, RSU vesting and SARs exercises with newly issued shares of the Company’s common stock. Stock-Based Compensation Expense The Company recognized the full impact of its share-based payment plans in the consolidated statements of operations and comprehensive income for the years 2017, 2016 and 2015. As of December 31, 2017 and 2016, the Company capitalized $471 of such cost on its consolidated balance sheet. The following table reflects the effect of recording stock-based compensation for the years 2017, 2016 and 2015: Years Ended December 31, 2017 2016 2015 Stock-based compensation expense by type of award: RSUs $ 22,428 $ 23,302 $ 11,885 SARs 529 700 — Employee stock purchase plan 1,421 1,226 1,128 Total stock-based compensation 24,378 25,228 13,013 Windfall tax effect on stock-based compensation (11,071 ) — — Net effect on net income $ 13,307 $ 25,228 $ 13,013 Effect on net earnings per share: Basic $ 0.25 $ 0.47 $ 0.24 Diluted $ 0.24 $ 0.47 $ 0.24 The pre-tax Years Ended December 31, 2017 2016 2015 Cost of revenues $ 3,894 $ 2,997 $ 1,814 Research and development expense 2,816 2,529 1,590 Selling, general and administrative expense 17,668 19,702 9,609 Total pre-tax $ 24,378 $ 25,228 $ 13,013 Valuation Assumptions The Company determines the fair value of RSUs based on the closing market price of the Company’s common stock on the date of the award, and estimates the fair value of stock options and employee stock purchase plan rights using the Black-Scholes valuation model. Such values are recognized as expense on a straight-line basis over the requisite service periods, net of estimated forfeitures except for retirement eligible employees in which the Company expenses the fair value of the grant in the period the grant is issued. The estimation of stock-based awards that will ultimately vest requires significant judgment. The Company considers many factors when estimating expected forfeitures, including types of awards and historical experience. Actual results, and future changes in estimates, may differ substantially from the Company’s current estimates. The Company did not grant options during 2017, 2016 and 2015. There were no options outstanding in 2017 and 2016. The total intrinsic value of options exercised during 2015 was approximately $494. The weighted average fair value per share of employee stock purchase plan rights granted in 2017, 2016 and 2015 was $13.14, $8.52 and $8.16, respectively. The fair value of the employees’ purchase plan rights was estimated using the Black-Scholes option-pricing model with the following weighted average assumptions: Years Ended December 31, 2017 2016 2015 Employee stock purchase plan rights: Expected life (years) 0.5 0.5 0.5 Risk-free interest rate 0.8 % 0.5 % 0.1 % Expected volatility 26.5 % 25.4 % 26.4 % Expected annual dividends per share $ 0.69 $ 0.68 $ 0.675 Expected volatilities for 2017, 2016 and 2015 are based on a combination of implied and historical volatilities of the Company’s common stock; the expected life represents the weighted average period of time that options granted are expected to be outstanding giving consideration to vesting schedules and the Company’s historical exercise patterns; and the risk-free interest rate is based on the U.S. Treasury yield curve in effect at the time of grant for periods corresponding with the expected life of the option. The total intrinsic value of options exercised, SARs exercised and the total fair value of RSUs vested during 2017, 2016 and 2015 was approximately $60,302, $18,844 and $12,868, respectively. As of December 31, 2017, the unrecognized compensation cost related to RSUs and SARs was approximately $20,314 and will be recognized over an estimated weighted average amortization period of 0.93 years.

Employee Benefit Plans

Employee Benefit Plans	12 Months Ended
	Dec. 31, 2017
Postemployment Benefits [Abstract]
Employee Benefit Plans	17) Employee Benefit Plans The Company has a 401(k) profit-sharing plan for U.S. employees meeting certain requirements in which eligible employees may contribute between 1% and 50% of their annual compensation to this plan, and, with respect to employees who are age 50 and older, certain specified additional amounts, limited by an annual maximum amount determined by the Internal Revenue Service. The Company, at its discretion, makes certain matching contributions to these plans based on participating employees’ contributions to the plans and their total compensation. The Company’s contributions were $5,651, $6,524 and $2,667 for 2017, 2016 and 2015, respectively. The Company maintains a bonus plan which provides cash awards to key employees, at the discretion of the compensation committee of the board of directors, based upon operating results and employee performance. In addition, the Company’s foreign locations also have various bonus plans based upon local operating results and employee performance. The total bonus expense was $46,783, $28,097 and $14,599 for 2017, 2016 and 2015, respectively. The Company provides supplemental retirement benefits for one of its current executive officers and a number of former retired executives. The total cost of these benefits was $3,478, $1,805 and $1,704 for 2017, 2016 and 2015, respectively. The accumulated benefit obligation was $15,929 and $12,450 at December 31, 2017 and 2016, respectively, which was included in other long-term liabilities. The Company also has a deferred compensation plan for certain Light & Motion segment executives. Defined Benefit Pension Plans As a result of the Newport Merger, the Company assumed all assets and liabilities of Newport’s defined benefit pension plans, which cover substantially all of its full-time employees in France, Germany, Israel and Japan. In addition, there are certain pension assets and liabilities relating to former employees in the United Kingdom. The German plan is unfunded, as permitted under the plan and applicable laws. For financial reporting purposes, the calculation of net periodic pension costs was based upon a number of actuarial assumptions including a discount rate for plan obligations, an assumed rate of return on pension plan assets and an assumed rate of compensation increase for employees covered by the plan. All of these assumptions were based upon management’s judgment, considering all known trends and uncertainties. Actual results that differ from these assumptions would impact future expense recognition and the cash funding requirements of the Company’s pension plans. The net periodic benefit costs for the plans included the following components: Year Ended December 31, 2017 2016 Service cost $ 708 $ 479 Interest cost on projected benefit obligations 458 377 Expected return on plan assets (116 ) (84 ) Amortization of actuarial net loss 400 406 $ 1,450 $ 1,178 The changes in projected benefit obligations and plan assets, as well as the ending balance sheet amounts for the Company’s defined benefit plans, were as follows: Year Ended December 31, 2017 2016 Change in projected benefit obligations: Projected benefit obligations, beginning of year(1) $ 23,450 $ 2,134 Liabilities assumed through acquisition — 22,437 Service cost 708 479 Interest cost 458 377 Actuarial (gain) loss (312 ) 1,085 Benefits paid (1,271 ) (897 ) Currency translation adjustments 2,703 (2,165 ) Projected benefit obligations, end of year $ 25,736 $ 23,450 Change in plan assets: Fair value of plan assets, beginning of year(1) $ 7,672 $ 301 Assets acquired through acquisition — 7,896 Company contributions 324 741 Gain on plan assets 177 66 Benefits paid (722 ) (437 ) Currency translation adjustments 701 (895 ) Fair value of plan assets, end of year 8,152 7,672 Net underfunded status $ (17,584 ) $ (15,778 ) (1) The beginning of the year balances for the year ended December 31, 2016, relate to plans held in Taiwan and Germany in the Vacuum & Analysis segment. These were not disclosed in prior years as the net liability was not material. Changes in plan assets and benefit obligations recognized in other comprehensive income (loss) included the following components: Year Ended December 31, 2017 2016 Amounts recognized in accumulated comprehensive income: Accumulated net actuarial (gain) loss $ (235 ) $ 465 Income tax benefit (88 ) (199 ) Accumulated other comprehensive (benefit) loss $ (323 ) $ 266 The Company’s Israeli plans account for the deferred vested benefits using the shut-down method of accounting, which resulted in assets of $15,048 and vested benefit obligations of $17,932, as of December 31, 2017 and assets of $13,910 and vested benefit obligations of $16,224, as of December 31, 2016. Under the shut-down method, the liability is calculated as if it were payable as of the balance sheet date, on an undiscounted basis. As of December 31, 2017, the estimated benefit payments for the next 10 years were as follows: Estimated benefit 2018 $ 2,283 2019 2,786 2020 2,900 2021 2,997 2022 2,858 2023-2027 13,027 $ 26,851 The Company expects to contribute $1,974 to the plans during 2018. The weighted-average rates used to determine the net periodic benefit costs were as follows: December 31, 2017 Discount rate 1.8 % Rate of increase in salary levels 2.2 Expected long-term rate of return on assets 1.9 In determining the expected long-term rate of return on plan assets, the Company considers the relative weighting of plan assets, the historical performance of total plan assets and individual asset classes, and economic and other indicators of future performance. Plan assets were held in the following categories as a percentage of total plan assets: Year Ended December 31, 2017 Amount Percentage Cash $ 561 7.0 % Debt securities 5,242 64.0 Equity securities 1,367 17.0 Other 982 12.0 $ 8,152 100.0 % In general, the Company’s asset management objectives include maintaining an adequate level of diversification to reduce interest rate and market risk while providing adequate liquidity to meet immediate and future benefit payment requirements. In Japan, assets are primarily invested in pooled funds of insurance companies. The expected long-term rate of return on these assets is approximately 1.5%, which is based on the general yield environment for high quality instruments in Japan. The United Kingdom pension plan invests in a combination of equity and bond funds. The allocation mix is designed to minimize risk while providing a rate of return that will provide asset growth which will be sufficient to cover expected liabilities. The expected long-term rate of return on these assets is approximately 2.6%, which is a combination of long dated government and corporate bond yields for the bond funds, and long dated government and corporate bond yields with an allowance for out-performance Other Pension-Related Assets As of December 31, 2017 and 2016, the Company had assets with an aggregate market value of $6,255 and $5,558, respectively, which it has set aside in connection with its German pension plans. These assets are invested in group insurance contracts through the insurance companies administering these plans, in accordance with applicable pension laws. The Germany contracts have a guaranteed minimum rate of return ranging from 2.25% to 4.25%, depending on the contract. Because the assets were not separate legal assets of the pension plan, they were not included in the Company’s plan assets shown above. However, the Company has designated such assets to pay pension benefits. Such assets are included in other assets in the accompanying consolidated balance sheet.

Net Income Per Share

Net Income Per Share	12 Months Ended
	Dec. 31, 2017
Earnings Per Share [Abstract]
Net Income Per Share	18) Net Income Per Share The following is a reconciliation of basic to diluted net income per share: Years Ended December 31, 2017 2016 2015 Numerator: Net income $ 339,132 $ 104,809 $ 122,297 Denominator: Shares used in net income per common share — basic 54,137,000 53,472,000 53,282,000 Effect of dilutive securities 937,000 579,000 278,000 Shares used in net income per common share — diluted 55,074,000 54,051,000 53,560,000 Net income per common share: Basic $ 6.26 $ 1.96 $ 2.30 Diluted $ 6.16 $ 1.94 $ 2.28 Basic earnings per share (“EPS”) is computed by dividing income available to common stockholders by the weighted-average number of common shares outstanding during the period. The computation of diluted EPS is similar to the computation of basic EPS except that the denominator is increased to include the number of additional common shares that would have been outstanding (using the treasury stock method) if securities containing potentially dilutive common shares (RSUs and SARs) had been converted to such common shares, and if such assumed conversion is dilutive. In 2017, 2016 and 2015, the potential dilutive effect of 404, 508 and 0 weighted average shares, respectively, of RSUs, were excluded from the computation of diluted weighted-average shares outstanding, as the shares would have had an anti-dilutive effect on EPS, and would thus need to be excluded from the computation of diluted weighted-average shares.

Business Segment, Geographic Ar

Business Segment, Geographic Area, Product and Significant Customer Information	12 Months Ended
	Dec. 31, 2017
Segment Reporting [Abstract]
Business Segment, Geographic Area, Product and Significant Customer Information	19) Business Segment, Geographic Area, Product and Significant Customer Information The Company is a global provider of instruments, subsystems and process control solutions that measure, monitor, deliver, analyze, power and control critical parameters of advanced manufacturing processes to improve process performance and productivity. The Company’s products are derived from its core competencies in pressure measurement and control, flow measurement and control, gas and vapor delivery, gas composition analysis, residual gas analysis, leak detection, control technology, ozone generation and delivery, RF & DC power, reactive gas generation, vacuum technology, lasers, photonics, sub-micron positioning, vibration control, and optics. The Company also provides services related to the maintenance and repair of its products, installation services and training. The Company’s Chief Operating Decision Maker (“CODM”) utilizes financial information to make decisions about allocating resources and assessing performance for the entire Company, which is used in the decision making process to assess performance. Based upon the information provided to the CODM, the Company has determined it has two reportable segments. Effective April 29, 2016, in conjunction with the Newport Merger, the Company changed its reportable segments based upon the organizational structure of the Company and how the CODM utilizes information provided to allocate resources and make decisions. The Company’s two reportable segments are: Vacuum & Analysis and Light & Motion. The Vacuum & Analysis segment represents the legacy MKS business and the Light & Motion segment represents the legacy Newport business. The Vacuum & Analysis segment provides a broad range of instruments, components and subsystems which are derived from the Company’s core competencies in pressure measurement and control, flow measurement and control, gas and vapor delivery, gas composition analysis, residual gas analysis, leak detection, control technology, ozone generation and delivery, RF & DC power, reactive gas generation and vacuum technology. The Light & Motion segment provides a broad range of instruments, components and subsystems which are derived from the Company’s core competencies in lasers, photonics, sub-micron The Company derives its segment results directly from the manner in which results are reported in its management reporting system. The accounting policies that the Company uses to derive reportable segment results are substantially the same as those used for external reporting purposes. The Company does not disclose external or intersegment revenues separately by reportable segment as this information is not presented to the CODM for decision making purposes. The following is net revenues by reportable segment: Years Ended December 31, 2017 2016 2015 Vacuum & Analysis $ 1,207,457 $ 872,291 $ 813,524 Light & Motion 708,520 423,051 — $ 1,915,977 $ 1,295,342 $ 813,524 The following is a reconciliation of segment gross profit to consolidated net income: Years Ended December 31, 2017 2016 2015 Gross profit by reportable segment: Vacuum & Analysis $ 551,078 $ 388,220 $ 362,872 Light & Motion 340,373 177,399 — Total gross profit by reportable segment 891,451 565,619 362,872 Operating expenses: Research and development 132,555 110,579 68,305 Selling, general and administrative 290,548 229,171 129,087 Acquisition and integration costs 5,332 27,279 30 Restructuring 3,920 642 2,074 Asset impairment 6,719 5,000 — Amortization of intangible assets 45,743 35,681 6,764 Income from operations 406,634 157,267 156,612 Interest income 3,021 2,560 2,999 Interest expense 30,990 30,611 143 Gain on sale of business 74,856 — — Other expense, net 5,896 1,239 — Income before income taxes 447,625 127,977 159,468 Provision for income taxes 108,493 23,168 37,171 Net income $ 339,132 $ 104,809 $ 122,297 The following is capital expenditures by reportable segment for the years ended December 31, 2017, 2016 and 2015: Vacuum & Analysis Light & Motion Total December 31, 2017: Capital expenditures $ 17,111 $ 14,176 $ 31,287 December 31, 2016: Capital expenditures $ 11,732 $ 7,391 $ 19,123 December 31, 2015: Capital expenditures $ 12,414 $ — $ 12,414 The following is depreciation and amortization of intangible assets by reportable segment for the years ended December 31, 2017, 2016 and 2015: Vacuum & Analysis Light & Motion Total December 31, 2017: Depreciation and amortization $ 20,297 $ 62,259 $ 82,556 December 31, 2016: Depreciation and amortization $ 20,820 $ 45,106 $ 65,926 December 31, 2015: Depreciation and amortization $ 22,103 $ — $ 22,103 Total income tax expense is not presented by reportable segment because the necessary information is not available or used by the CODM. The following is segment assets by reportable segment: Vacuum & Analysis Light & Motion Corporate, Total December 31, 2017: Segment assets: Accounts receivable $ 201,318 $ 119,934 $ (20,944 ) $ 300,308 Inventory 197,831 141,250 — 339,081 Total segment assets $ 399,149 $ 261,184 $ (20,944 ) $ 639,389 Vacuum & Analysis Light & Motion Corporate, Total December 31, 2016: Segment assets: Accounts receivable $ 148,516 $ 121,516 $ (21,275 ) $ 248,757 Inventory 165,040 110,829 — 275,869 Total segment assets $ 313,556 $ 232,345 $ (21,275 ) $ 524,626 A reconciliation of segment assets to consolidated total assets is as follows: Years Ended December 31, 2017 2016 Total segment assets $ 639,389 $ 524,626 Cash and cash equivalents, restricted cash and investments 553,976 433,231 Other current assets 53,543 50,770 Property, plant and equipment, net 171,782 174,559 Goodwill and intangible assets, net 957,445 996,589 Other assets 37,883 32,467 Consolidated total assets $ 2,414,018 $ 2,212,242 Information about the Company’s operations in different geographic regions is presented in the tables below. Net revenues to unaffiliated customers are based on the location in which the sale originated. Transfers between geographic areas are at negotiated transfer prices and have been eliminated from consolidated net revenues. Years Ended December 31, Net revenues: 2017 2016 2015 United States $ 955,284 $ 675,601 $ 458,313 South Korea 212,763 112,432 106,909 Japan 167,318 96,954 62,879 Europe 209,912 156,365 79,927 Asia (excluding South Korea and Japan) 370,700 253,990 105,496 $ 1,915,977 $ 1,295,342 $ 813,524 Years Ended December 31, Long-lived assets:(1) 2017 2016 United States $ 124,689 $ 122,547 Europe 28,820 28,717 Asia 49,645 49,406 $ 203,154 $ 200,670 (1) Long-lived assets include property, plant and equipment, net and certain other assets, and exclude goodwill and intangibles and long-term tax-related Goodwill associated with each of our reportable segments is as follows: Years Ended December 31, 2017 2016 Reportable segment: Vacuum & Analysis $ 197,617 $ 199,453 Light & Motion 393,430 389,132 Total goodwill $ 591,047 $ 588,585 Worldwide Product Information Because the reportable segment information above does not reflect worldwide sales of the Company’s products, the Company groups its products into six groups of similar products based upon the similarity of product function. Worldwide net revenue for each group of products is as follows: Years Ended December 31, 2017 2016 2015 Analytical and Control Solutions Products $ 131,376 $ 115,758 $ 102,658 Power, Plasma and Reactive Gas Solutions Products 564,343 367,665 350,469 Vacuum Solutions Products 511,738 388,868 360,397 Laser Products 225,168 124,432 — Optics Products 203,775 124,218 — Photonics Products 279,577 174,401 — $ 1,915,977 $ 1,295,342 $ 813,524 Sales of Analytical and Control Solutions Products; Power, Plasma and Reactive Gas Solutions Products; and Vacuum Solutions Products are included in the Company’s Vacuum & Analysis segment. Sales of Laser Products; Optics Products; and Photonics Products are included in the Light & Motion segment. Major Customers The Company had two customers with net revenues greater than 10% of total net revenues in the periods shown as follows: Years Ended December 31, 2017 2016 2015 Applied Materials, Inc. 12.7 % 13.6 % 17.8 % Lam Research Corporation 11.7 % 11.2 % 13.4 % Net revenues for each of our reportable segments include revenues from each of the two customers, which represent net revenues greater than 10% of total net revenues.

Restructurings

Restructurings	12 Months Ended
	Dec. 31, 2017
Restructuring and Related Activities [Abstract]
Restructurings	20) Restructurings During 2017, the Company recorded restructuring charges of $3,920. The restructuring charges were primarily severance and facility costs related to the consolidation of two manufacturing plants, a restructuring of one of our international facilities and the consolidation of sales offices. During 2016, the Company recorded restructuring charges of $642. The restructuring charges were primarily severance costs related to the consolidation of one of our international facilities. The activity related to the Company’s restructuring accrual is shown below: 2017 2016 Balance at January 1 $ 540 $ 807 Restructuring liability from Newport Merger — 562 Charged to expense 3,920 642 Payments and adjustment (1,216 ) (1,471 ) Balance at December 31 $ 3,244 $ 540

Commitments and Contingencies

Commitments and Contingencies	12 Months Ended
	Dec. 31, 2017
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	21) Commitments and Contingencies On March 9, 2016, a putative class action lawsuit captioned Dixon Chung v. Newport Corp., et al., Case No. A-16-733154-C, Hubert C. Pincon v. Newport Corp., et al. A-16-734039-B, On October 19, 2016, plaintiffs filed an amended complaint captioned In re Newport Corporation Shareholder Litigation A-16-733154-B, pre- On July 27, 2017, plaintiffs filed a second amended complaint, which names as defendants certain former directors of Newport. On August 8, 2017, the Court dismissed the Company and Newport from the action pursuant to stipulations among the parties. The second amended complaint alleges that the directors breached their fiduciary duties to Newport’s stockholders by agreeing to sell Newport through an inadequate and unfair process, which led to inadequate and unfair consideration, and by omitting material information from the proxy statement. The second amended complaint seeks monetary damages, including pre- The Company is subject to various legal proceedings and claims, which have arisen in the ordinary course of business. In the opinion of management, the ultimate disposition of these matters will not have a material adverse effect on the Company’s results of operations, financial condition or cash flows. The Company leases certain of its facilities and machinery and equipment under operating leases expiring in various years through 2026. Generally, the facility leases require the Company to pay maintenance, insurance and real estate taxes. Rental expense under operating leases totaled $19,693, $16,253 and $7,845 for 2017, 2016 and 2015, respectively. Minimum lease payments under operating leases are as follows: Year Ending December 31, Operating Leases 2018 $ 18,489 2019 15,563 2020 12,828 2021 9,177 2022 7,385 Thereafter 3,956 Total minimum lease payments $ 67,398 As of December 31, 2017, the Company has entered into purchase commitments for certain inventory components and other equipment and services used in its normal operations. The majority of these purchase commitments covered by these arrangements are for periods of less than one year and aggregate to approximately $278,797. To the extent permitted by Massachusetts law, the Company’s Restated Articles of Organization, as amended, require the Company to indemnify any of its current or former officers or directors or any person who has served or is serving in any capacity with respect to any of the Company’s employee benefit plans. The Company believes that the estimated exposure for these indemnification obligations is currently not material. Accordingly, the Company has no material liabilities recorded for these requirements as of December 31, 2017. The Company also enters into agreements in the ordinary course of business which include indemnification provisions. Pursuant to these agreements, the Company indemnifies, holds harmless and agrees to reimburse the indemnified party, generally its customers, for losses suffered or incurred by the indemnified party in connection with certain patent or other intellectual property infringement claims, and, in some instances, other claims, by any third party with respect to the Company’s As part of past acquisitions and divestitures of businesses or assets, the Company has provided a variety of indemnifications to the sellers and purchasers for certain events or occurrences that took place prior to the date of the acquisition or divestiture. Typically, certain of the indemnifications expire after a defined period of time following the transaction, but certain indemnifications may survive indefinitely. The maximum potential amount of future payments the Company could be required to make for such obligations is undeterminable at this time. Other than obligations recorded as liabilities at the time of the acquisitions, historically the Company has not made significant payments for these indemnifications. Accordingly, no material liabilities have been recorded for these obligations. In conjunction with certain asset sales, the Company may provide routine indemnifications whose terms range in duration and often are not explicitly defined. Where appropriate, an obligation for such indemnification is recorded as a liability. Because the amounts of liability under these types of indemnifications are not explicitly stated, the overall maximum amount of the obligation under such indemnifications cannot be reasonably estimated. Other than obligations recorded as liabilities at the time of the asset sale, historically the Company has not made significant payments for these indemnifications.

Supplemental Financial Data

Supplemental Financial Data	12 Months Ended
	Dec. 31, 2017
Quarterly Financial Information Disclosure [Abstract]
Supplemental Financial Data	MKS Instruments, Inc. Supplemental Financial Data Quarter Ended March 31 June 30 Sept. 30 Dec. 31 (Table in thousands, except per share data) (Unaudited) 2017 Statement of Operations Data Net revenues $ 437,153 $ 480,757 $ 486,267 $ 511,800 Gross profit 205,547 219,583 227,995 238,326 Income from operations 83,580 92,883 110,155 120,016 Net income $ 65,060 $ 120,440 $ 75,994 $ 77,638 Net income per share: Basic $ 1.21 $ 2.22 $ 1.40 $ 1.43 Diluted $ 1.18 $ 2.19 $ 1.38 $ 1.41 Cash dividends paid per common share $ 0.175 $ 0.175 $ 0.175 $ 0.18 2016 Statement of Operations Data Net revenues(1) $ 183,681 $ 325,861 $ 380,660 $ 405,140 Gross profit 77,913 135,913 168,385 183,408 Income from operations 22,559 19,186 53,008 62,514 Net income $ 17,563 $ 9,210 $ 32,549 $ 45,487 Net income per share: Basic $ 0.33 $ 0.17 $ 0.61 $ 0.85 Diluted $ 0.33 $ 0.17 $ 0.60 $ 0.83 Cash dividends paid per common share $ 0.17 $ 0.17 $ 0.17 $ 0.17 (1) The increase in net revenues in the quarter ended June 30, 2016, compared to the quarter ended March 31, 2016, related to the Newport Merger which closed on April 29, 2016.

Schedule II - Valuation and Qua

Schedule II - Valuation and Qualifying Accounts	12 Months Ended
	Dec. 31, 2017
Valuation and Qualifying Accounts [Abstract]
Schedule II - Valuation and Qualifying Accounts	MKS INSTRUMENTS, INC. SCHEDULE II—VALUATION AND QUALIFYING ACCOUNTS Additions Description Balance at Acquisition Balance Charged to Charged Deductions & Balance at (in thousands) Allowance for doubtful accounts: Years ended December 31, 2017 $ 3,909 $ — $ 825 $ — $ (599 ) $ 4,135 2016 $ 1,760 $ 1,292 $ 1,109 $ (66 ) $ (186 ) $ 3,909 2015 $ 2,250 $ — $ (255 ) $ 21 $ (256 ) $ 1,760 Additions Description Balance at Acquisition Balance Charged to Charged Deductions & Balance at (in thousands) Allowance for sales returns: Years ended December 31, 2017 $ 1,138 $ — $ (142 ) $ — $ 299 $ 1,295 2016 $ 601 $ 423 $ 2,262 $ — $ (2,148 ) $ 1,138 2015 $ 730 $ — $ 2,500 $ (3 ) $ (2,626 ) $ 601 Additions Description Balance at Acquisition Balance Charged to Charged Deductions Balance at (in thousands) Valuation allowance on deferred tax asset: Years ended December 31, 2017 $ 12,527 $ — $ 1,603 $ — $ (501 ) $ 13,629 2016 $ 6,127 $ 3,769 $ 2,719 $ — $ (88 ) $ 12,527 2015 $ 26,763 $ — $ — $ 113 $ (20,749 ) $ 6,127

Basis of Presentation (Policies

Basis of Presentation (Policies)	12 Months Ended
	Dec. 31, 2017
Accounting Policies [Abstract]
Use of Estimates	Use of Estimates The consolidated financial statements have been prepared in accordance with accounting principles generally accepted in the United States of America (“U.S. GAAP”). The preparation of these financial statements requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and the disclosure of contingent liabilities at the date of the financial statements and the reported amounts of revenues and expenses during the reporting period. On an on-going
Revenue Recognition and Accounts Receivable Allowances	Revenue Recognition and Accounts Receivable Allowances Revenue from product sales is recorded upon transfer of title and risk of loss to the customer provided that there is evidence of an arrangement, the sales price is fixed or determinable, and collection of the related receivable is reasonably assured. In most transactions, the Company has no obligations to customers after the date products are shipped other than pursuant to warranty obligations. In some instances, the Company provides installation, training, support and services to customers after the product has been shipped. For those revenue arrangements with multiple deliverables, the Company allocates revenue to each element based upon its relative selling price using vendor-specific objective evidence (“VSOE”), or third-party evidence (“TPE”) or based upon the relative selling price using estimated prices if VSOE or TPE does not exist. The Company then recognizes revenue on each deliverable in accordance with its policies for product and service revenue recognition. The Company provides for the estimated costs to fulfill customer warranty obligations upon the recognition of the related revenue. Shipping and handling fees, if any, billed to customers are recognized as revenue. The related shipping and handling costs are recognized in cost of revenues. Accounts receivable allowances include sales returns and bad debt allowances. The Company monitors and tracks the amount of product returns and reduces revenue at the time of shipment for the estimated amount of such future returns, based on historical experience. The Company makes estimates evaluating its allowance for doubtful accounts. The Company continuously monitors collections and payments from its customers and maintains a provision for estimated credit losses based upon its historical experience and any specific customer collection issues that it has identified.
Research and Development	Research and Development Research and development costs are expensed as incurred and consist mainly of compensation-related expenses and project materials. The Company’s research and development efforts include numerous projects, which generally have a duration of 3 to 30 months. Acquired in-process
Advertising Costs	Advertising Costs Advertising costs are expensed as incurred and were immaterial in 2017, 2016 and 2015.
Stock-Based Compensation	Stock-Based Compensation The accounting for share-based compensation expense requires the measurement and recognition of compensation expense for all share-based payment awards made to employees and directors based on estimated fair values. For restricted stock units (“RSUs”), the fair value is the fair value on the date of grant that normally vests over a three year period. The Company also provides employees the opportunity to purchase shares through an employee stock purchase plan. For shares issued under its employee stock purchase plan, the Company has estimated the fair value on the date of grant using the Black Scholes pricing model, which is affected by the Company’s stock price as well as assumptions regarding a number of complex and subjective variables. These variables include the Company’s expected stock price volatility over the term of the awards, expected life, risk-free interest rate and expected dividends. The Company is also required to estimate forfeitures at the time of grant and revise those estimates in subsequent periods if actual forfeitures differ from those estimates. Management determined that blended volatility, a combination of historical and implied volatility, is more reflective of market conditions and a better indicator of expected volatility than historical or implied volatility alone. The assumptions used in calculating the fair value of share-based payment awards represent management’s best estimates, but these estimates involve inherent uncertainties and the application of management judgment. As a result, if factors change and the Company uses different assumptions, its stock-based compensation expense could be materially different in the future.
Accumulated Other Comprehensive Income	Accumulated Other Comprehensive Income For foreign subsidiaries where the functional currency is the local currency, assets and liabilities are translated into U.S. dollars at the current exchange rate on the balance sheet date. Revenue and expenses are translated at average rates of exchange prevailing during the year. Translation adjustments resulting from this process are recorded to Accumulated Other Comprehensive Income (“OCI”). Unrealized gains and losses on securities classified as available-for-sale
Net Income Per Share	Net Income Per Share Basic net income per share is based on the weighted average number of common shares outstanding, and diluted net income per share is based on the weighted average number of common shares outstanding and all potential dilutive common equivalent shares outstanding. The dilutive effect of options is determined under the treasury stock method using the average market price for the period. Common equivalent shares are included in the per share calculations when the effect of their inclusion would be dilutive.
Cash and Cash Equivalents and Investments	Cash and Cash Equivalents and Investments All highly liquid investments with a maturity date of three months or less at the date of purchase are considered to be cash equivalents. The appropriate classification of investments in securities is determined at the time of purchase. Debt securities that the Company does not have the intent and ability to hold to maturity are classified as “available-for-sale” The Company classifies investments with maturity dates greater than twelve months in short-term investments rather than long-term investments. This method classifies these securities as current based on the nature of the securities and the availability for use in current operations. The Company believes this method is preferable because it is more reflective of the Company’s assessment of its overall liquidity position. The Company reviews its investment portfolio on a quarterly basis to identify and evaluate individual investments that have indications of possible impairment. The factors considered in determining whether a loss is other-than-temporary include: the length of time and extent to which fair market value has been below the cost basis, the financial condition and near-term prospects of the issuer, credit quality, and the Company’s ability to hold the investment for a period of time sufficient to allow for any anticipated recovery in fair value.
Concentrations of Credit Risk	Concentrations of Credit Risk The Company’s significant concentrations of credit risk consist principally of cash and cash equivalents, investments, forward exchange contracts and trade accounts receivable. The Company maintains cash and cash equivalents with financial institutions including some banks with which it had borrowings. The Company maintains investments primarily in U.S. Treasury and government agency securities and corporate debt securities. The Company enters into forward currency contracts with high credit-quality financial institutions in order to minimize credit risk exposure. The Company’s largest customers are primarily concentrated in the semiconductor industry, and a limited number of these customers account for a significant portion of the Company’s revenues. The Company regularly monitors the creditworthiness of its customers and believes it has adequately provided for potential credit loss exposures. Credit is extended for all customers based primarily on financial condition, and collateral is not required. The Company had one customer, Applied Materials, Inc., comprising 13%, 14% and 18% of net revenues for 2017, 2016 and 2015, respectively, and another customer, Lam Research Corporation, comprising 12%, 11% and 13% of net revenues for 2017, 2016 and 2015, respectively. During the years 2017, 2016 and 2015, approximately 57%, 56% and 69% of the Company’s net revenues, respectively, were from sales to semiconductor capital equipment manufacturers and semiconductor device manufacturers. One customer, Applied Materials, Inc., represented 10% or more of the Company’s accounts receivable balance as of December 31, 2017.
Inventories	Inventories Inventories are stated at the lower of cost or market, cost being determined using a standard costing system which approximates cost based on a first-in, first-out
Property, Plant and Equipment	Property, Plant and Equipment Property, plant and equipment are stated at cost. Expenditures for major renewals and betterments that extend the useful lives of property, plant and equipment are capitalized. Expenditures for maintenance and repairs are charged to expense as incurred. When assets are sold or otherwise disposed of, the cost and related accumulated depreciation are eliminated from the accounts and any resulting gain or loss is recognized in earnings. Depreciation is provided on the straight-line method over the estimated useful lives of twenty to thirty-one one-half
Intangible Assets	Intangible Assets Intangible assets resulting from the acquisitions of businesses are estimated by management based on the fair value of assets acquired. These include acquired customer lists, technology, patents, trade names, covenants not to compete and IPR&D. Intangible assets are amortized from one to eighteen years on a straight-line basis which represents the estimated periods of benefit and the expected pattern of consumption.
Goodwill	Goodwill Goodwill is the amount by which the cost of acquired net assets exceeded the fair value of those net assets on the date of acquisition. The Company allocates goodwill to reporting units at the time of acquisition or when there is a change in the reporting structure and bases that allocation on which reporting units will benefit from the acquired assets and liabilities. Reporting units are defined as operating segments or one level below an operating segment, referred to as a component. The Company assesses goodwill for impairment on an annual basis as of October 31 or more frequently when events and circumstances occur indicating that the recorded goodwill may be impaired. The estimated fair value of the Company’s reporting units are based on discounted cash flow models derived from internal earnings and internal and external market forecasts. Determining fair value requires the exercise of significant judgment, including judgments about appropriate discount rates, perpetual growth rates and the amount and timing of expected future cash flows. Discount rates are based on a weighted average cost of capital (“WACC”), which represents the average rate a business must pay its providers of debt and equity. The WACC used to test goodwill is derived from a group of comparable companies. Assumptions in estimating future cash flows are subject to a high degree of judgment and complexity. The Company makes every effort to forecast these future cash flows as accurately as possible with the information available at the time the forecast is developed. In performing the Company’s annual goodwill impairment test, the Company is permitted to first assess qualitative factors to determine whether it is more likely than not that the fair value of our reporting unit is less than its carrying amount, including goodwill. The qualitative assessment, is commonly referred to as “step zero.” In performing the qualitative step zero assessment, the Company considers certain events and circumstances specific to the reporting unit and to the entity as a whole, such as macroeconomic conditions, industry and market considerations, overall financial performance and cost factors when evaluating whether it is more likely than not that the fair value of the reporting unit is less than its carrying amount. The Company is also permitted to bypass the qualitative assessment and proceed directly to the quantitative test. If the Company chooses to undertake the qualitative assessment and concludes that it is more likely than not that the fair value of the reporting unit is less than its carrying amount, the Company would then proceed to the quantitative impairment test. In the quantitative assessment, the Company compares the fair value of the reporting unit to its carrying amount, which includes goodwill. If the fair value exceeds the carrying value, no impairment loss exists. If the fair value is less than the carrying amount, a goodwill impairment loss is measured and recorded. As of October 31, 2017, the Company performed its annual impairment assessment of goodwill using the qualitative step zero assessment and determined that it is more likely than not that the fair values of the reporting units exceed their carrying amount.
Impairment of Long-Lived Assets	Impairment of Long-Lived Assets The Company evaluates the recoverability of its long-lived assets whenever events and changes in circumstances indicate that the carrying amount of an asset may not be fully recoverable. This periodic review may result in an adjustment of estimated depreciable lives or asset impairment. When indicators of impairment are present, the carrying values of the asset are evaluated in relation to their operating performance and future undiscounted cash flows of the underlying business. If the future undiscounted cash flows are less than their carrying value, impairment exists. The impairment is measured as the difference between the carrying value and the fair value of the underlying asset. Fair values are based on estimates of market prices and assumptions concerning the amount and timing of estimated future cash flows and assumed discount rates, reflecting varying degrees of perceived risk. In 2017, the Company recorded an impairment charge of $6,719 related to certain long-lived assets as a result of consolidating two manufacturing plants.
Foreign Exchange	Foreign Exchange The functional currency of the majority of the Company’s foreign subsidiaries is the applicable local currency. For those subsidiaries, assets and liabilities are translated to U.S. dollars at year-end Net foreign exchange losses resulting from re-measurement re-measurement
Income Taxes	Income Taxes The Company records income taxes using the asset and liability method. Deferred income tax assets and liabilities are recognized for the future tax consequences attributable to differences between the financial statement carrying amounts of existing assets and liabilities and their respective income tax bases, and also for operating loss and tax credit carry-forwards. On a quarterly basis, the Company evaluates both the positive and negative evidence that affects the realizability of net deferred tax assets and assesses the need for a valuation allowance. The future benefit to be derived from its deferred tax assets is dependent upon its ability to generate sufficient future taxable income in each jurisdiction of the right type to realize the assets. The Company records a valuation allowance to reduce its net deferred tax assets to the amount that is more likely than not to be realized. To the extent the Company establishes a valuation allowance an expense will be recorded as a component of the provision for income taxes on the statement of operations. During 2015, the Company decreased its valuation allowance by $20,636 primarily related to the expiration of U.S. capital loss carry-forwards. As a result, the valuation allowance was $6,127 at December 31, 2015. During 2016, the Company increased its valuation allowance by $6,400 primarily related to the addition of historical valuation allowances for Newport and its subsidiaries which were included as a result of the acquisition in April 2016. As a result, the valuation allowance was $12,527 at December 31, 2016. During 2017, the Company increased its valuation allowance by $1,102, primarily related to certain state tax credits. As a result, the valuation allowance was $13,629 at December 31, 2017. Accounting for income taxes requires a two-step re-evaluates On December 22, 2017, the President of the United States signed into law the Tax Cuts and Jobs Act (the “Act”), which included significant changes to U.S. tax law. Some of the more significant changes impacting the Company are the reduction of the U.S. federal corporate income tax rate from 35.0% to 21.0% as of January 1, 2018, the implementation of a territorial tax system and the imposition of a transition tax on deemed repatriated cumulative earnings of foreign subsidiaries (“transition tax”). Income tax effects resulting from changes in tax are generally accounted for by the Company in the period in which the law is enacted and the effects are recorded as a component of provision for income taxes from continuing operations. On December 22, 2017, the Securities and Exchange Commission Staff issued Staff Accounting Bulletin No. 118 (“SAB 118”) to provide guidance for reporting entities’ ability to timely complete the accounting for certain income tax effects of the Act. In accordance with SAB 118, the Company has computed and reported reasonable estimates related to the transition tax and the revaluation of deferred tax assets and liabilities and included these provisional amounts in its consolidated financial statements for the year ended December 31, 2017. The estimates of the impacts of the Act on the Company are based on the Company’s current assumptions and understandings of the provisions of the Act. The ultimate impacts of the Act on the Company may differ from these provisional amounts due to additional analysis, changes in interpretations and assumptions by the Company and additional regulatory guidance that may be issued. The Company is required to finalize its estimate of the effects of the Act within a measurement period ending when the Company has obtained, prepared and analyzed the information needed to complete the accounting requirements under Accounting Standards Codification (“ASC”) Topic 740.
Recently Issued Accounting Pronouncements	In August 2017, the Financial Accounting Standards Board (“FASB”) issued Accounting Standards Update (“ASU”) 2017-12, In May 2017, the FASB issued ASU 2017-09, In March 2017, the FASB issued ASU 2017-07, In January 2017, the FASB issued ASU 2017-01, In November 2016, the FASB issued ASU 2016-18, 2016-15. beginning-of-period end-of-period 2016-15. In October 2016, the FASB issued ASU 2016-16, In August 2016, the FASB issued ASU 2016-15, In February 2016, the FASB issued ASU 2016-02, In January 2016, the FASB issued ASU 2016-01, “Financial 825-10): In May 2014, the FASB issued ASU 2014-09, The FASB issued additional updates to the new revenue standard in Topic 606 relating to reporting revenue on a gross versus net basis (Update 2016-08 2016-10 2016-12 2016-20 2017-13 2017-14
Intangibles-Goodwill and Other	In January 2017, the FASB issued ASU 2017-04,

Investments (Tables)

Investments (Tables)	12 Months Ended
	Dec. 31, 2017
Investments, Debt and Equity Securities [Abstract]
Short-Term and Long-Term Investments Available-for-Sale and Cost Method Investments	Investments classified as short-term consist of the following: Years Ended December 31, Available-for-sale 2017 2016 Time deposits and certificates of deposit $ 9,757 $ 23,818 Bankers’ acceptance drafts 5,330 1,439 Asset-backed securities 36,990 36,809 Commercial paper 13,750 24,381 Corporate obligations 77,821 46,707 Municipal bonds 1,970 591 Promissory note — 675 U.S. treasury obligations 28,078 25,414 U.S. agency obligations 35,738 29,629 $ 209,434 $ 189,463 Investments classified as long-term consist of the following: Years Ended December 31, Available-for-sale 2017 2016 Group insurance contracts $ 6,255 $ 5,558 Cost method investments: Minority interest in a private company(1) 4,400 4,300 $ 10,655 $ 9,858 (1) In April of 2016 the Company invested $9,300 for a minority interest in a private company. During 2016, the Company recognized $5,000 of impairment charges related to this cost method investment. In July 2017, the Company invested an additional $100 in this private company.
Gross Unrealized Gains and (Losses) Aggregated by Investment Category	The following table shows the gross unrealized gains and (losses) aggregated by investment category for available-for-sale As of December 31, 2017: Cost Gross Gross Estimated Short-term investments: Available-for-sale Time deposits and certificates of deposit $ 9,756 $ 1 $ — $ 9,757 Bankers acceptance drafts 5,330 — — 5,330 Asset-backed securities 37,017 15 (42 ) 36,990 Commercial paper 13,810 — (60 ) 13,750 Corporate obligations 77,788 58 (25 ) 77,821 Municipal bonds 1,970 — — 1,970 U.S. treasury obligations 28,054 24 — 28,078 U.S. agency obligations 35,728 10 — 35,738 $ 209,453 $ 108 $ (127 ) $ 209,434 As of December 31, 2017: Cost Gross Gross Estimated Long-term investments: Available-for-sale Group insurance contracts $ 6,006 $ 249 $ — $ 6,255 As of December 31, 2016: Cost Gross Gross Estimated Short-term investments: Available-for-sale Time deposits and certificates of deposit $ 23,818 $ — $ — $ 23,818 Bankers acceptance drafts 1,439 — — 1,439 Asset-backed securities 36,847 6 (44 ) 36,809 Commercial paper 24,423 — (42 ) 24,381 Corporate obligations 46,700 21 (14 ) 46,707 Municipal bonds 591 — — 591 Promissory note 675 — — 675 U.S. treasury obligations 25,414 — — 25,414 U.S. agency obligations 29,631 8 (10 ) 29,629 $ 189,538 $ 35 $ (110 ) $ 189,463 As of December 31, 2016: Cost Gross Gross Estimated Long-term investments: Available-for-sale Group insurance contracts $ 5,432 $ 126 $ — $ 5,558

Fair Value Measurements (Tables

Fair Value Measurements (Tables)	12 Months Ended
	Dec. 31, 2017
Fair Value Disclosures [Abstract]
Schedule of Fair Value of Assets and Liabilities Measured on Recurring Basis	Assets and liabilities of the Company measured at fair value on a recurring basis as of December 31, 2017, are summarized as follows: Fair Value Measurements at Reporting Date Using Description December 31, Quoted Prices in (Level 1) Significant Other (Level 2) Significant (Level 3) Assets: Cash equivalents: Money market funds $ 4,987 $ 4,987 $ — $ — Time deposits and certificates of deposit 2,100 — 2,100 — Commercial paper 30,475 — 30,475 — Restricted cash – money market funds 119 119 — — Available-for-sale — Time deposits and certificates of deposit 9,757 — 9,757 — Bankers acceptance drafts 5,330 — 5,330 — Asset-backed securities 36,990 — 36,990 — Commercial paper 13,750 — 13,750 — Corporate obligations 77,821 — 77,821 — Municipal bonds 1,970 — 1,970 — U.S. treasury obligations 28,078 — 28,078 — U.S. agency obligations 35,738 — 35,738 — Group insurance contracts 6,255 — 6,255 — Derivatives – currency forward contracts 168 — 168 — Funds in investments and other assets: — Israeli pension assets 15,048 — 15,048 — Derivatives - interest rate hedge - non-current 6,179 — 6,179 — Restricted cash – non-current 1,010 1,010 — — Total assets $ 275,775 $ 6,116 $ 269,659 $ — Liabilities: Derivatives – currency forward contracts $ 6,198 $ — $ 6,198 $ — Reported as follows: Assets: Cash and cash equivalents(1) $ 37,562 $ 4,987 $ 32,575 $ — Restricted cash 119 119 — — Short-term investments 209,434 — 209,434 — Other current assets 168 — 168 — Total current assets $ 247,283 $ 5,106 $ 242,177 $ — Long-term investments(2) $ 6,255 $ — $ 6,255 $ — Other assets 22,237 1,010 21,227 — Total long-term assets $ 28,492 $ 1,010 $ 27,482 $ — Liabilities: Other current liabilities $ 6,198 $ — $ 6,198 $ — (1) The cash and cash equivalent amounts presented in the table above do not include cash of $292,808 and non-negotiable (2) The long-term investments presented in the table above do not include our minority interest investment in a private company, which is accounted for under the cost method. Assets and liabilities of the Company measured at fair value on a recurring basis as of December 31, 2016, are summarized as follows: Fair Value Measurements at Reporting Date Using Description December 31, Quoted Prices in (Level 1) Significant Other (Level 2) Significant (Level 3) Assets: Cash equivalents: Money market funds $ 10,155 $ 10,155 $ — $ — Time deposits and certificates of deposit 4,900 — 4,900 — Bankers acceptance drafts 448 — 448 — Commercial paper 11,828 — 11,828 — Corporate obligations 2,025 — 2,025 — U.S. agency obligations 3,899 — 3,899 — Restricted cash – money market funds 5,287 5,287 — — Available-for-sale Time deposits and certificates of deposit 23,818 — 23,818 — Bankers acceptance drafts 1,439 — 1,439 — Asset-backed securities 36,809 — 36,809 — Commercial paper 24,381 — 24,381 — Corporate obligations 46,707 — 46,707 — Municipal bonds 591 — 591 — Promissory note 675 — 675 — U.S. treasury obligations 25,414 — 25,414 — U.S. agency obligations 29,629 — 29,629 — Group insurance contracts 5,558 — 5,558 — Derivatives – currency forward contracts 2,985 — 2,985 — Derivatives – options contracts 4 — 4 — Funds in investments and other assets: Israeli pension assets 13,910 — 13,910 — Derivatives - interest rate hedge - non-current 4,900 — 4,900 — Restricted cash – non-current 573 573 — — Total assets $ 255,935 $ 16,015 $ 239,920 $ — Liabilities: Derivatives – currency forward contracts 543 — 543 — Derivatives – options contracts 16 — 16 — Total liabilities $ 559 $ — $ 559 $ — Reported as follows: Assets: Cash and cash equivalents(1) $ 33,255 $ 10,155 $ 23,100 $ — Restricted cash 5,287 5,287 — — Short-term investments 189,463 — 189,463 — Other current assets 2,989 — 2,989 — Total current assets $ 230,994 $ 15,442 $ 215,552 $ — Long-term investments(2) $ 5,558 $ — $ 5,558 $ — Other assets 19,383 573 18,810 — Total long-term assets $ 24,941 $ 573 $ 24,368 $ — Liabilities: Other current liabilities $ 559 $ — $ 559 $ — (1) The cash and cash equivalent amounts presented in the table above do not include cash of $192,432 and non-negotiable (2) The long-term investments presented in the table above do not include our minority interest investment in a private company, which is accounted for under the cost method.

Derivatives (Tables)

Derivatives (Tables)	12 Months Ended
	Dec. 31, 2017
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Summary of Primary Net Hedging Positions and Corresponding Fair Values	The following tables provide a summary of the primary net hedging positions and corresponding fair values held as of December 31, 2017 and 2016: December 31, 2017 Currency Hedged (Buy/Sell) Gross Notional Fair Value(1) U.S. Dollar/Japanese Yen $ 70,175 $ (233 ) U.S. Dollar/South Korean Won 79,672 (3,799 ) U.S. Dollar/Euro 26,140 (1,047 ) U.S. Dollar/U.K. Pound Sterling 12,104 (337 ) U.S. Dollar/Taiwan Dollar 20,831 (614 ) Total $ 208,922 $ (6,030 ) December 31, 2016 Currency Hedged (Buy/Sell) Gross Notional Fair Value(1) U.S. Dollar/Japanese Yen $ 30,522 $ 763 U.S. Dollar/South Korean Won 50,049 1,342 U.S. Dollar/Euro 18,040 156 U.S. Dollar/U.K. Pound Sterling 6,067 117 U.S. Dollar/Taiwan Dollar 15,530 64 Total $ 120,208 $ 2,442 (1) Represents the receivable (payable) amount included in the consolidated balance sheet.
Summary of Fair Value Amounts of Company's Derivative Instruments	The following table provides a summary of the fair value amounts of the Company’s derivative instruments: Years Ended December 31, Derivatives Designated as Hedging Instruments 2017 2016 Derivative assets: Forward exchange contracts(1) $ 168 $ 2,985 Foreign currency interest rate hedge(2) 6,179 4,900 Derivative liabilities: Forward exchange contracts(1) (6,198 ) (543 ) Total net derivative asset designated as hedging instruments $ 149 $ 7,342 (1) The derivative asset of $168 and derivative liability of $(6,198) related to the forward foreign exchange contracts are classified in other current assets and other current liabilities in the consolidated balance sheet as of December 31, 2017. The derivative asset of $2,985 and derivative liability of $(543) are classified in other current assets and other current liabilities in the consolidated balance sheet as of December 31, 2016. These forward foreign exchange contracts are subject to a master netting agreement with one financial institution. However, the Company has elected to record these contracts on a gross basis in the balance sheet. (2) The foreign currency interest rate hedge asset of $6,179 and $4,900 is classified in other assets in the consolidated balance sheet as of December 31, 2017 and 2016, respectively.
Summary of (Losses) Gains on Derivatives Designated as Cash Flow Hedging Instruments	The following table provides a summary of the (losses) gains on derivatives designated as cash flow hedging instruments: Years Ended December 31, Derivatives Designated as Cash Flow Hedging Instruments 2017 2016 2015 Forward exchange contracts: Net (loss) gain recognized in OCI(1) $ (6,036 ) $ 5,914 $ (3,748 ) Net (loss) gain reclassified from OCI into income(2) $ (2,685 ) $ (1,414 ) $ 3,520 (1) Net change in the fair value of the effective portion classified in OCI. (2) Effective portion classified as cost of products in 2017, 2016 and 2015.
Summary of Losses on Derivatives Not Designated as Cash Flow Hedging Instruments	The following table provides a summary of losses on derivatives not designated as cash flow hedging instruments: Years Ended December 31, Derivatives Not Designated as Hedging Instruments 2017 2016 2015 Forward exchange contracts: Net loss recognized in income(1) $ (3,416 ) $ (31 ) $ (40 ) (1) The Company enters into forward foreign exchange contracts to hedge against changes in the balance sheet for certain subsidiaries to mitigate the risk associated with certain foreign currency transactions in the ordinary course of business. These derivatives are not designated as cash flow hedging instruments and gains or losses from these derivatives are recorded immediately in other expense, net in 2017 and 2016 and in selling, general and administrative expenses in 2015.

Inventories (Tables)

Inventories (Tables)	12 Months Ended
	Feb. 22, 2018
Inventory Disclosure [Abstract]
Summary of Inventories	Inventories consist of the following: Years Ended December 31, 2017 2016 Raw material $ 191,351 $ 150,150 Work-in-process 54,050 39,105 Finished goods 93,680 86,614 $ 339,081 $ 275,869

Property, Plant and Equipment (

Property, Plant and Equipment (Tables)	12 Months Ended
	Feb. 22, 2018
Property, Plant and Equipment [Abstract]
Summary of Property, Plant and Equipment	Property, plant and equipment consist of the following: Years Ended December 31, 2017 2016 Land $ 11,650 $ 11,115 Buildings 103,563 100,169 Machinery and equipment 317,073 297,342 Furniture and fixtures, office equipment and software 145,945 139,392 Leasehold improvements 65,293 63,431 Construction in progress 13,619 6,592 657,143 618,041 Less: accumulated depreciation 485,361 443,482 $ 171,782 $ 174,559

Acquisitions and Dispositions (

Acquisitions and Dispositions (Tables)	12 Months Ended
	Dec. 31, 2017
Newport [Member]
Summary of Purchase Price	The purchase price of Newport consisted of the following: Cash paid for outstanding shares(1) $ 905,254 Settlement of share-based compensation awards(2) 8,824 Cash paid for Newport debt(3) 93,200 Total purchase price $ 1,007,278 Less: cash and cash equivalents acquired (61,463 ) Total purchase price, net of cash and cash equivalents acquired $ 945,815 (1) Represents cash paid of $23.00 per share for approximately 39,359,000 shares of Newport common stock, without interest and subject to a deduction for any required withholding tax. (2) Represents the vested but unissued portion of Newport share-based compensation awards as of the acquisition date of April 29, 2016. (3) Represents the cash paid for the outstanding balance of Newport’s senior secured revolving credit agreement.
Summary of Estimated Fair Value of Assets Acquired and Liabilities Assumed	The following table summarizes the allocation of the purchase price to the fair values assigned to assets acquired and liabilities assumed at the date of the Newport Merger: Current assets (including cash) $ 186,137 Inventory 142,714 Intangible assets 404,506 Goodwill 396,027 Property, plant and equipment 119,932 Long-term assets 22,725 Total assets acquired 1,272,041 Current liabilities 95,156 Intangible liability 4,302 Other long-term liabilities 165,305 Total liabilities assumed 264,763 Fair value of assets acquired and liabilities assumed 1,007,278 Less: cash and cash equivalents acquired (61,463 ) Total purchase price, net of cash and cash equivalents acquired $ 945,815
Allocation of Acquired Intangible Assets and Related Estimates of Useful Lives	The following table reflects the allocation of the acquired intangible assets and liabilities and related estimate of useful lives: Order backlog $ 12,100 1 year Customer relationships 247,793 6-18 Trademarks and trade names 55,900 Indefinite Developed technology 75,386 4-8 In-process 6,899 Undefined (1) Leasehold interest (favorable) 6,428 4-5 Total intangible assets $ 404,506 Leasehold interest (unfavorable) $ 4,302 (1) The useful lives of in-process
Schedule of Unaudited Pro Forma Financial Information	The following unaudited pro forma financial information presents the combined results of operations of the Company as if the Newport Merger had occurred on January 1, 2015. The unaudited pro forma financial information is not necessarily indicative of what the Company’s condensed consolidated results of operations actually would have been had the acquisition occurred at the beginning of each year. In addition, the unaudited pro forma financial information does not attempt to project the future results of operations of the combined company. Years Ended December 31, 2016 2015 Total net revenues $ 1,475,637 $ 1,412,748 Net income 111,076 69,096 Net income per share: Basic $ 2.08 $ 1.30 Diluted $ 2.06 $ 1.29
Precisive, LLC [Member]
Summary of Estimated Fair Value of Assets Acquired and Liabilities Assumed	The following table summarizes the estimated fair value of the assets acquired and liabilities assumed at the date of the Precisive acquisition: Current assets $ 693 Non-current 18 Intangible assets 5,110 Goodwill 7,042 Total assets acquired 12,863 Total current liabilities assumed 343 Fair value of asset acquired and liabilities assumed 12,520 Less: cash acquired (435 ) Total purchase price, net of cash acquired $ 12,085
Allocation of Acquired Intangible Assets and Related Estimates of Useful Lives	Substantially all of the purchase price is deductible for tax purposes. The following table reflects the allocation of the acquired intangible assets and related estimates of useful lives. These acquired intangibles will be amortized on a straight-line basis, which approximates the pattern of use. Order backlog $ 50 18 months Customer relationships 1,430 8 years Exclusive patent license 2,600 10 years Trade names 210 10 years Developed technology 820 10 years Total intangible assets $ 5,110

Goodwill and Intangible Assets

Goodwill and Intangible Assets (Tables)	12 Months Ended
	Dec. 31, 2017
Goodwill and Intangible Assets Disclosure [Abstract]
Goodwill	The changes in the carrying amount of goodwill and accumulated impairment losses were as follows: 2017 2016 Gross Accumulated Net Gross Accumulated Net Beginning balance at January 1 $ 727,999 $ (139,414 ) $ 588,585 $ 339,117 $ (139,414 ) $ 199,703 Acquired goodwill(1) — — — 396,027 — 396,027 Sale of business(2) (3,115 ) — (3,115 ) — — — Impairment loss(3) — (4,862 ) (4,862 ) — — — Foreign currency translation 10,439 — 10,439 (7,145 ) — (7,145 ) Ending balance at December 31 $ 735,323 $ (144,276 ) $ 591,047 $ 727,999 $ (139,414 ) $ 588,585 (1) During 2016, the Company recorded $396,027 of goodwill related to the Newport Merger. (2) In 2017, the Company sold its Data Analytics business and, as a result, charged the related goodwill of $3,115 to the gain on sale of business. (3) In 2017, the Company recorded an impairment loss of $4,862 related to the write-off
Intangible Assets	Components of the Company’s acquired intangible assets are comprised of the following: As of December 31, 2017 Gross Impairment Accumulated Foreign Net Completed technology(1) $ 172,431 $ (105 ) $ (115,371 ) $ 333 $ 57,288 Customer relationships(1) 282,744 (1,406 ) (45,518 ) 1,571 237,391 Patents, trademarks, trade names and other(1) 110,523 — (38,730 ) (74 ) 71,719 $ 565,698 $ (1,511 ) $ (199,619 ) $ 1,830 $ 366,398 As of December 31, 2016 Gross Impairment Accumulated Foreign Net Completed technology(2) $ 176,586 $ — $ (97,707 ) $ (1,068 ) $ 77,811 Customer relationships(2) 285,044 — (29,709 ) (3,404 ) 251,931 Patents, trademarks, trade names and other(2) 111,723 — (33,397 ) (64 ) 78,262 $ 573,353 $ — $ (160,813 ) $ (4,536 ) $ 408,004 (1) In 2017, the Company sold its Data Analytics business and, as a result, wrote off the related intangibles of $4,155 of completed technology, $2,300 of customer relationships and $1,200 of patents, trademarks, trade names and other, which were fully amortized at the time of sale. (2) During 2016, the Company recorded $404,506 of separately identified intangible assets related to the Newport Merger, of which $75,386 was completed technology, $247,793 was customer relationships and $81,327 was patents, trademarks, trade names, in-process
Estimated Net Amortization Expense	Aggregate net amortization expense related to acquired intangible assets and unfavorable lease commitments for future years is: Year Amount 2018 $ 43,404 2019 40,333 2020 28,262 2021 20,464 2022 17,703 Thereafter 157,360

Product Warranties (Tables)

Product Warranties (Tables)	12 Months Ended
	Dec. 31, 2017
Guarantees and Product Warranties [Abstract]
Product Warranty Activities	Product warranty activities were as follows: Years Ended December 31, 2017 2016 Beginning balance $ 8,261 $ 5,205 Product warranty liability from Newport Merger — 3,040 Provisions for product warranties 15,884 8,858 Direct and other charges to warranty liability (14,041 ) (8,842 ) Ending balance(1) $ 10,104 $ 8,261 (1) Short-term product warranty of $9,719 and long-term product warranty of $385, each as of December 31, 2017, are included within other current liabilities and other liabilities, respectively, within the accompanying consolidated balance sheet. Short-term product warranty of $8,200 and long-term product warranty of $61 as of December 31, 2016, are included within other current liabilities and other liabilities, respectively, within the accompanying consolidated balance sheet.

Debt (Tables)

Debt (Tables)	12 Months Ended
	Dec. 31, 2017
Debt Disclosure [Abstract]
Schedule of Short-Term Debt	Short-term debt: December 31, 2017 December 31, 2016 Japanese lines of credit $ 2,750 $ 4,245 Japanese receivables financing facility 215 458 Other debt 7 8 Current portion of Term Loan Facility — 6,282 $ 2,972 $ 10,993 (1) Net of deferred financing fees, original issuance discount and re-pricing
Schedule of Long-Term Debt	Long-term debt: December 31, 2017 December 31, 2016 Austrian loans due through March 2020 $ 714 $ 548 Term Loan Facility, net(1) 389,279 600,681 $ 389,993 $ 601,229 (1) Net of deferred financing fees, original issuance discount and re-pricing
Schedule of Contractual Maturities of Debt Obligations	Contractual maturities of the Company’s debt obligations as of December 31, 2017 are as follows: Year Amount 2018 $ 2,972 2019 639 2020 75 2021 — 2022 — Thereafter 398,464

Income Taxes (Tables)

Income Taxes (Tables)	12 Months Ended
	Dec. 31, 2017
Income Tax Disclosure [Abstract]
Reconciliation of Company's Effective Tax Rate to U.S. Federal Statutory Rate	A reconciliation of the Company’s effective tax rate to the U.S. federal statutory rate is as follows: Years Ended December 31, 2017 2016 2015 U.S. Federal income tax statutory rate 35.0 % 35.0 % 35.0 % Federal tax credits (0.7 ) (1.8 ) (1.2 ) State income taxes, net of federal benefit 1.0 0.8 1.3 Effect of foreign operations taxed at various rates (12.1 ) (12.7 ) (6.4 ) Qualified production activity tax benefit (1.4 ) (2.9 ) (1.6 ) Transition tax, net of foreign tax credits 6.4 — — Revaluation of US deferred income taxes (5.0 ) — — Stock based compensation (2.5 ) — — Deferred tax asset valuation allowance (0.1 ) 2.1 — Release of income tax reserves (including interest) (0.4 ) (2.4 ) (4.8 ) Foreign dividends, net of foreign tax credits 3.3 (2.2 ) 0.7 Acquisition and integration related costs — 1.5 — Other 0.7 0.7 0.3 24.2 % 18.1 % 23.3 %
Components of Income from Operations Before Income Taxes and Related Provision for Income Taxes	The components of income from operations before income taxes and the related provision for income taxes consist of the following: Years Ended December 31, 2017 2016 2015 Income from operations before income taxes: United States $ 224,979 $ 42,491 $ 90,401 Foreign 222,646 85,486 69,067 $ 447,625 $ 127,977 $ 159,468 Current taxes: United States $ 77,023 $ 17,693 $ 15,813 State 6,149 2,359 2,927 Foreign 30,152 41,938 18,021 113,324 61,990 36,761 Deferred taxes: United States (16,250 ) (23,604 ) (862 ) State and Foreign 11,419 (15,218 ) 1,272 (4,831 ) (38,822 ) 410 Provision for income taxes $ 108,493 $ 23,168 $ 37,171
Significant Components of Deferred Tax Assets and Deferred Tax Liabilities	The significant components of the deferred tax assets and deferred tax liabilities are as follows: Years Ended December 31, 2017 2016 Deferred tax assets: Carry-forward losses and credits $ 25,834 $ 50,673 Inventory and warranty reserves 17,734 24,253 Accrued expenses and other reserves 15,393 16,176 Stock-based compensation 5,092 8,995 Executive supplemental retirement benefits 4,984 6,888 Other 597 — Total deferred tax assets $ 69,634 $ 106,985 Deferred tax liabilities: Acquired intangible assets (83,092 ) (127,571 ) Depreciation and amortization (10,150 ) (16,428 ) Loan costs (2,157 ) (7,282 ) Foreign withholding taxes (16,206 ) — Unrealized gain (469 ) (3,195 ) Other — (1,336 ) Total deferred tax liabilities (112,074 ) (155,812 ) Valuation allowance (13,629 ) (12,527 ) Net deferred tax (liabilities) assets $ (56,069 ) $ (61,354 )
Reconciliation of Beginning and Ending Amount of Gross Unrecognized Tax Benefits	A reconciliation of the beginning and ending amount of gross unrecognized tax benefits is as follows: Years Ended December 31, 2017 2016 2015 Balance at beginning of year $ 25,465 $ 4,332 $ 19,610 Increases/(decreases) for prior years 640 (195 ) (26 ) Increases for the current year 4,340 23,940 322 Reductions related to settlements with taxing authorities — — (15,370 ) Reductions related to expiration of statute of limitations (3,100 ) (2,612 ) (204 ) Balance at end of year $ 27,345 $ 25,465 $ 4,332

Stock-Based Compensation (Table

Stock-Based Compensation (Tables)	12 Months Ended
	Dec. 31, 2017
Summary of Activity for RSUs	The following table presents the activity for RSUs under the Plans: Year Ended December 31, 2017 Non-vested RSUs Weighted Non-vested 1,325,516 $ 34.38 Accrued dividend shares Granted 122 389,610 78.34 67.69 Vested (684,967 ) 34.58 Forfeited or expired (86,902 ) 38.97 Non-vested 943,379 $ 47.57
Summary of Activity for Outstanding and Exercisable Stock Appreciation Rights	At December 31, 2017, the Company’s outstanding and exercisable SARs, the weighted-average base value, the weighted average remaining contractual life and the aggregate intrinsic value thereof, were as follows: Number Weighted Average Weighted Average Aggregate Intrinsic SARs outstanding 282,907 $ 28.62 3.3 $ 18,639 SARs exercisable 221,375 $ 27.92 3.0 $ 14,740
Effect of Recording Stock-Based Compensation	The following table reflects the effect of recording stock-based compensation for the years 2017, 2016 and 2015: Years Ended December 31, 2017 2016 2015 Stock-based compensation expense by type of award: RSUs $ 22,428 $ 23,302 $ 11,885 SARs 529 700 — Employee stock purchase plan 1,421 1,226 1,128 Total stock-based compensation 24,378 25,228 13,013 Windfall tax effect on stock-based compensation (11,071 ) — — Net effect on net income $ 13,307 $ 25,228 $ 13,013 Effect on net earnings per share: Basic $ 0.25 $ 0.47 $ 0.24 Diluted $ 0.24 $ 0.47 $ 0.24
Pre-Tax Effect Within Consolidated Statements of Operations of Recording Stock-Based Compensation	The pre-tax Years Ended December 31, 2017 2016 2015 Cost of revenues $ 3,894 $ 2,997 $ 1,814 Research and development expense 2,816 2,529 1,590 Selling, general and administrative expense 17,668 19,702 9,609 Total pre-tax $ 24,378 $ 25,228 $ 13,013
Fair Value of Employees' Purchase Rights Estimated using Black-Scholes Option-Pricing Model	The fair value of the employees’ purchase plan rights was estimated using the Black-Scholes option-pricing model with the following weighted average assumptions: Years Ended December 31, 2017 2016 2015 Employee stock purchase plan rights: Expected life (years) 0.5 0.5 0.5 Risk-free interest rate 0.8 % 0.5 % 0.1 % Expected volatility 26.5 % 25.4 % 26.4 % Expected annual dividends per share $ 0.69 $ 0.68 $ 0.675
Stock Appreciation Rights (SARs) [Member]
Summary of Activity for Outstanding and Exercisable Stock Appreciation Rights	The following table presents the activity for SARs under the Plans: Year Ended December 31, 2017 Non-vested SARs Weighted SARs — beginning of period 599,334 $ 28.10 Exercised (289,822 ) 27.60 Forfeited or expired (26,605 ) 28.07 SARs Outstanding — end of period 282,907 $ 28.62

Employee Benefit Plans (Tables)

Employee Benefit Plans (Tables)	12 Months Ended
	Dec. 31, 2017
Postemployment Benefits [Abstract]
Summary of Net Periodic Benefit Costs	The net periodic benefit costs for the plans included the following components: Year Ended December 31, 2017 2016 Service cost $ 708 $ 479 Interest cost on projected benefit obligations 458 377 Expected return on plan assets (116 ) (84 ) Amortization of actuarial net loss 400 406 $ 1,450 $ 1,178
Summary of Changes in Projected Benefit Obligations and Plan Assets, and Ending Balances of Defined Benefit Plans	The changes in projected benefit obligations and plan assets, as well as the ending balance sheet amounts for the Company’s defined benefit plans, were as follows: Year Ended December 31, 2017 2016 Change in projected benefit obligations: Projected benefit obligations, beginning of year(1) $ 23,450 $ 2,134 Liabilities assumed through acquisition — 22,437 Service cost 708 479 Interest cost 458 377 Actuarial (gain) loss (312 ) 1,085 Benefits paid (1,271 ) (897 ) Currency translation adjustments 2,703 (2,165 ) Projected benefit obligations, end of year $ 25,736 $ 23,450 Change in plan assets: Fair value of plan assets, beginning of year(1) $ 7,672 $ 301 Assets acquired through acquisition — 7,896 Company contributions 324 741 Gain on plan assets 177 66 Benefits paid (722 ) (437 ) Currency translation adjustments 701 (895 ) Fair value of plan assets, end of year 8,152 7,672 Net underfunded status $ (17,584 ) $ (15,778 ) (1) The beginning of the year balances for the year ended December 31, 2016, relate to plans held in Taiwan and Germany in the Vacuum & Analysis segment. These were not disclosed in prior years as the net liability was not material.
Summary of Changes in Plan Assets and Benefit Obligations Recognized in Other Comprehensive Income (Loss)	Changes in plan assets and benefit obligations recognized in other comprehensive income (loss) included the following components: Year Ended December 31, 2017 2016 Amounts recognized in accumulated comprehensive income: Accumulated net actuarial (gain) loss $ (235 ) $ 465 Income tax benefit (88 ) (199 ) Accumulated other comprehensive (benefit) loss $ (323 ) $ 266
Summary of Estimated Benefit Payments for Next 10 Years	As of December 31, 2017, the estimated benefit payments for the next 10 years were as follows: Estimated benefit 2018 $ 2,283 2019 2,786 2020 2,900 2021 2,997 2022 2,858 2023-2027 13,027 $ 26,851
Schedule of Weighted Average Rates Used to Determine Net Periodic Benefit Costs	The weighted-average rates used to determine the net periodic benefit costs were as follows: December 31, 2017 Discount rate 1.8 % Rate of increase in salary levels 2.2 Expected long-term rate of return on assets 1.9
Schedule of Defined Benefit Plan Assets	Plan assets were held in the following categories as a percentage of total plan assets: Year Ended December 31, 2017 Amount Percentage Cash $ 561 7.0 % Debt securities 5,242 64.0 Equity securities 1,367 17.0 Other 982 12.0 $ 8,152 100.0 %

Net Income Per Share (Tables)

Net Income Per Share (Tables)	12 Months Ended
	Dec. 31, 2017
Earnings Per Share [Abstract]
Reconciliation of Basic and Diluted Net Income Per Share	The following is a reconciliation of basic to diluted net income per share: Years Ended December 31, 2017 2016 2015 Numerator: Net income $ 339,132 $ 104,809 $ 122,297 Denominator: Shares used in net income per common share — basic 54,137,000 53,472,000 53,282,000 Effect of dilutive securities 937,000 579,000 278,000 Shares used in net income per common share — diluted 55,074,000 54,051,000 53,560,000 Net income per common share: Basic $ 6.26 $ 1.96 $ 2.30 Diluted $ 6.16 $ 1.94 $ 2.28

Business Segment, Geographic 45

Business Segment, Geographic Area, Product and Significant Customer Information (Tables)	12 Months Ended
	Dec. 31, 2017
Segment Reporting [Abstract]
Net Revenues, Assets and Goodwill by Reportable Segment	The following is net revenues by reportable segment: Years Ended December 31, 2017 2016 2015 Vacuum & Analysis $ 1,207,457 $ 872,291 $ 813,524 Light & Motion 708,520 423,051 — $ 1,915,977 $ 1,295,342 $ 813,524 The following is segment assets by reportable segment: Vacuum & Analysis Light & Motion Corporate, Total December 31, 2017: Segment assets: Accounts receivable $ 201,318 $ 119,934 $ (20,944 ) $ 300,308 Inventory 197,831 141,250 — 339,081 Total segment assets $ 399,149 $ 261,184 $ (20,944 ) $ 639,389 Vacuum & Analysis Light & Motion Corporate, Total December 31, 2016: Segment assets: Accounts receivable $ 148,516 $ 121,516 $ (21,275 ) $ 248,757 Inventory 165,040 110,829 — 275,869 Total segment assets $ 313,556 $ 232,345 $ (21,275 ) $ 524,626 Goodwill associated with each of our reportable segments is as follows: Years Ended December 31, 2017 2016 Reportable segment: Vacuum & Analysis $ 197,617 $ 199,453 Light & Motion 393,430 389,132 Total goodwill $ 591,047 $ 588,585
Reconciliation of Segment Gross Profit to Consolidated Net Income	The following is a reconciliation of segment gross profit to consolidated net income: Years Ended December 31, 2017 2016 2015 Gross profit by reportable segment: Vacuum & Analysis $ 551,078 $ 388,220 $ 362,872 Light & Motion 340,373 177,399 — Total gross profit by reportable segment 891,451 565,619 362,872 Operating expenses: Research and development 132,555 110,579 68,305 Selling, general and administrative 290,548 229,171 129,087 Acquisition and integration costs 5,332 27,279 30 Restructuring 3,920 642 2,074 Asset impairment 6,719 5,000 — Amortization of intangible assets 45,743 35,681 6,764 Income from operations 406,634 157,267 156,612 Interest income 3,021 2,560 2,999 Interest expense 30,990 30,611 143 Gain on sale of business 74,856 — — Other expense, net 5,896 1,239 — Income before income taxes 447,625 127,977 159,468 Provision for income taxes 108,493 23,168 37,171 Net income $ 339,132 $ 104,809 $ 122,297
Schedule of Capital Expenditures, Depreciation and Amortization Expense of Intangible Assets by Reportable Segment	The following is capital expenditures by reportable segment for the years ended December 31, 2017, 2016 and 2015: Vacuum & Analysis Light & Motion Total December 31, 2017: Capital expenditures $ 17,111 $ 14,176 $ 31,287 December 31, 2016: Capital expenditures $ 11,732 $ 7,391 $ 19,123 December 31, 2015: Capital expenditures $ 12,414 $ — $ 12,414 The following is depreciation and amortization of intangible assets by reportable segment for the years ended December 31, 2017, 2016 and 2015: Vacuum & Analysis Light & Motion Total December 31, 2017: Depreciation and amortization $ 20,297 $ 62,259 $ 82,556 December 31, 2016: Depreciation and amortization $ 20,820 $ 45,106 $ 65,926 December 31, 2015: Depreciation and amortization $ 22,103 $ — $ 22,103
Reconciliation of Segment Assets to Consolidated Total Assets	A reconciliation of segment assets to consolidated total assets is as follows: Years Ended December 31, 2017 2016 Total segment assets $ 639,389 $ 524,626 Cash and cash equivalents, restricted cash and investments 553,976 433,231 Other current assets 53,543 50,770 Property, plant and equipment, net 171,782 174,559 Goodwill and intangible assets, net 957,445 996,589 Other assets 37,883 32,467 Consolidated total assets $ 2,414,018 $ 2,212,242
Schedule of Net Revenues and Long-Lived Assets by Geographic Regions	Transfers between geographic areas are at negotiated transfer prices and have been eliminated from consolidated net revenues. Years Ended December 31, Net revenues: 2017 2016 2015 United States $ 955,284 $ 675,601 $ 458,313 South Korea 212,763 112,432 106,909 Japan 167,318 96,954 62,879 Europe 209,912 156,365 79,927 Asia (excluding South Korea and Japan) 370,700 253,990 105,496 $ 1,915,977 $ 1,295,342 $ 813,524 Years Ended December 31, Long-lived assets:(1) 2017 2016 United States $ 124,689 $ 122,547 Europe 28,820 28,717 Asia 49,645 49,406 $ 203,154 $ 200,670 (1) Long-lived assets include property, plant and equipment, net and certain other assets, and exclude goodwill and intangibles and long-term tax-related
Worldwide Net Revenue for Each Group of Products	Worldwide net revenue for each group of products is as follows: Years Ended December 31, 2017 2016 2015 Analytical and Control Solutions Products $ 131,376 $ 115,758 $ 102,658 Power, Plasma and Reactive Gas Solutions Products 564,343 367,665 350,469 Vacuum Solutions Products 511,738 388,868 360,397 Laser Products 225,168 124,432 — Optics Products 203,775 124,218 — Photonics Products 279,577 174,401 — $ 1,915,977 $ 1,295,342 $ 813,524
Customers with Net Revenues Greater than 10% of Total Net Revenues	The Company had two customers with net revenues greater than 10% of total net revenues in the periods shown as follows: Years Ended December 31, 2017 2016 2015 Applied Materials, Inc. 12.7 % 13.6 % 17.8 % Lam Research Corporation 11.7 % 11.2 % 13.4 %

Restructurings (Tables)

Restructurings (Tables)	12 Months Ended
	Dec. 31, 2017
Restructuring and Related Activities [Abstract]
Schedule of Company's Restructuring Activity	The activity related to the Company’s restructuring accrual is shown below: 2017 2016 Balance at January 1 $ 540 $ 807 Restructuring liability from Newport Merger — 562 Charged to expense 3,920 642 Payments and adjustment (1,216 ) (1,471 ) Balance at December 31 $ 3,244 $ 540

Commitments and Contingencies (

Commitments and Contingencies (Tables)	12 Months Ended
	Dec. 31, 2017
Commitments and Contingencies Disclosure [Abstract]
Minimum Lease Payments under Operating Lease	Minimum lease payments under operating leases are as follows: Year Ending December 31, Operating Leases 2018 $ 18,489 2019 15,563 2020 12,828 2021 9,177 2022 7,385 Thereafter 3,956 Total minimum lease payments $ 67,398

Supplemental Financial Data (Ta

Supplemental Financial Data (Tables)	12 Months Ended
	Dec. 31, 2017
Quarterly Financial Information Disclosure [Abstract]
Schedule of Supplemental Financial Data	MKS Instruments, Inc. Supplemental Financial Data Quarter Ended March 31 June 30 Sept. 30 Dec. 31 (Table in thousands, except per share data) (Unaudited) 2017 Statement of Operations Data Net revenues $ 437,153 $ 480,757 $ 486,267 $ 511,800 Gross profit 205,547 219,583 227,995 238,326 Income from operations 83,580 92,883 110,155 120,016 Net income $ 65,060 $ 120,440 $ 75,994 $ 77,638 Net income per share: Basic $ 1.21 $ 2.22 $ 1.40 $ 1.43 Diluted $ 1.18 $ 2.19 $ 1.38 $ 1.41 Cash dividends paid per common share $ 0.175 $ 0.175 $ 0.175 $ 0.18 2016 Statement of Operations Data Net revenues(1) $ 183,681 $ 325,861 $ 380,660 $ 405,140 Gross profit 77,913 135,913 168,385 183,408 Income from operations 22,559 19,186 53,008 62,514 Net income $ 17,563 $ 9,210 $ 32,549 $ 45,487 Net income per share: Basic $ 0.33 $ 0.17 $ 0.61 $ 0.85 Diluted $ 0.33 $ 0.17 $ 0.60 $ 0.83 Cash dividends paid per common share $ 0.17 $ 0.17 $ 0.17 $ 0.17 (1) The increase in net revenues in the quarter ended June 30, 2016, compared to the quarter ended March 31, 2016, related to the Newport Merger which closed on April 29, 2016.

Business Description - Addition

Business Description - Additional Information (Detail)	12 Months Ended
	Dec. 31, 2017SegmentProduct
Number Of Product Groups And Reportable Segments [Abstract]
Number of product groups | Product	6
Number of reportable segments | Segment	2

Summary of Significant Accoun50

Summary of Significant Accounting Policies - Additional Information (Detail) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017USD ($)Customer	Dec. 31, 2016USD ($)	Dec. 31, 2015USD ($)
Schedule Of Significant Accounting Policies [Line Items]
Minimum period of company's research and development projects		3 months
Maximum period of company's research and development projects		30 months
Vesting period		3 years
Maximum maturity period of liquid investments		3 years
Maturity dates for short-term investments		12 months
Amortization period of leasehold improvements		Shorter of the lease term or the estimated useful life of the leased asset.
Asset impairment charge		$ 6,719	$ 5,000
Increase (decrease) in valuation allowance on state tax credit carryforwards		1,102	6,400	$ (20,636)
Valuation allowance		$ 13,629	$ 12,527	$ 6,127
Minimum percentage of recognition of tax benefits from uncertain tax positions		50.00%
U.S. federal corporate income tax rate		35.00%	35.00%	35.00%
Other Expense [Member]
Schedule Of Significant Accounting Policies [Line Items]
Net foreign exchange losses from re-measurement		$ (6,132)	$ (2,823)
Selling, General and Administrative Expenses [Member]
Schedule Of Significant Accounting Policies [Line Items]
Net foreign exchange losses from re-measurement				$ (1,388)
Customer Concentration Risk [Member] | Accounts Receivable [Member]
Schedule Of Significant Accounting Policies [Line Items]
Number of customers comprising of Accounts Receivable | Customer		1
Customer Concentration Risk [Member] | Customer A [Member] | Sales Revenue, Net [Member]
Schedule Of Significant Accounting Policies [Line Items]
Concentration risk, percentage		13.00%	14.00%	18.00%
Customer Concentration Risk [Member] | Customer B [Member] | Sales Revenue, Net [Member]
Schedule Of Significant Accounting Policies [Line Items]
Concentration risk, percentage		12.00%	11.00%	13.00%
Customer Concentration Risk [Member] | Semiconductor Products [Member] | Sales Revenue, Net [Member]
Schedule Of Significant Accounting Policies [Line Items]
Concentration risk, percentage		57.00%	56.00%	69.00%
Scenario, Forecast [Member]
Schedule Of Significant Accounting Policies [Line Items]
U.S. federal corporate income tax rate	21.00%
Minimum [Member]
Schedule Of Significant Accounting Policies [Line Items]
Intangible assets amortized period		1 year
Minimum [Member] | Credit Concentration Risk [Member] | Accounts Receivable [Member]
Schedule Of Significant Accounting Policies [Line Items]
Concentration risk, percentage		10.00%
Minimum [Member] | Buildings [Member]
Schedule Of Significant Accounting Policies [Line Items]
Estimated useful lives		20 years
Minimum [Member] | Machinery and Equipment [Member]
Schedule Of Significant Accounting Policies [Line Items]
Estimated useful lives		3 years
Minimum [Member] | Furniture and Fixtures [Member]
Schedule Of Significant Accounting Policies [Line Items]
Estimated useful lives		3 years
Minimum [Member] | Office Equipment [Member]
Schedule Of Significant Accounting Policies [Line Items]
Estimated useful lives		3 years
Maximum [Member]
Schedule Of Significant Accounting Policies [Line Items]
Intangible assets amortized period		18 years
Maximum [Member] | Buildings [Member]
Schedule Of Significant Accounting Policies [Line Items]
Estimated useful lives		31 years 6 months
Maximum [Member] | Machinery and Equipment [Member]
Schedule Of Significant Accounting Policies [Line Items]
Estimated useful lives		10 years
Maximum [Member] | Furniture and Fixtures [Member]
Schedule Of Significant Accounting Policies [Line Items]
Estimated useful lives		10 years
Maximum [Member] | Office Equipment [Member]
Schedule Of Significant Accounting Policies [Line Items]
Estimated useful lives		10 years

Investments - Investments Class

Investments - Investments Classified as Short-Term Available-for-Sale Investments (Detail) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Schedule of Available-for-sale Securities [Line Items]
Fair value of available-for-sale investments	$ 209,434	$ 189,463
Time Deposits and Certificates of Deposit [Member]
Schedule of Available-for-sale Securities [Line Items]
Fair value of available-for-sale investments	9,757	23,818
Bankers Acceptance Drafts [Member]
Schedule of Available-for-sale Securities [Line Items]
Fair value of available-for-sale investments	5,330	1,439
Asset-Backed Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Fair value of available-for-sale investments	36,990	36,809
Commercial Paper [Member]
Schedule of Available-for-sale Securities [Line Items]
Fair value of available-for-sale investments	13,750	24,381
Corporate Obligations [Member]
Schedule of Available-for-sale Securities [Line Items]
Fair value of available-for-sale investments	77,821	46,707
Municipal Bonds [Member]
Schedule of Available-for-sale Securities [Line Items]
Fair value of available-for-sale investments	1,970	591
Promissory Note [Member]
Schedule of Available-for-sale Securities [Line Items]
Fair value of available-for-sale investments		675
U.S. Treasury Obligations [Member]
Schedule of Available-for-sale Securities [Line Items]
Fair value of available-for-sale investments	28,078	25,414
U.S. Agency Obligations [Member]
Schedule of Available-for-sale Securities [Line Items]
Fair value of available-for-sale investments	$ 35,738	$ 29,629

Investments - Investments Cla52

Investments - Investments Classified as Long-Term Available-for-Sale Investments and Long-Term Cost Method Investments (Detail) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Schedule of Available-for-sale Securities and Cost-method Investments [Line Items]
Investments classified as long-term	$ 10,655	$ 9,858
Available-for-Sale Investments [Member] | Group Insurance Contracts [Member]
Schedule of Available-for-sale Securities and Cost-method Investments [Line Items]
Investments classified as long-term	6,255	5,558
Cost-method Investments [Member] | Minority Interest in Private Company [Member]
Schedule of Available-for-sale Securities and Cost-method Investments [Line Items]
Investments classified as long-term	$ 4,400	$ 4,300

Investments - Investments Cla53

Investments - Investments Classified as Long-Term Available-for-Sale Investments and Long-Term Cost Method Investments (Parenthetical) (Detail) - Minority Interest in Private Company [Member] - USD ($) $ in Thousands	1 Months Ended		3 Months Ended	12 Months Ended
	Jul. 31, 2017	Apr. 30, 2016	Dec. 31, 2016	Dec. 31, 2016
Schedule of Cost-method Investments [Line Items]
Investments in minority interest	$ 100	$ 9,300
Impairment charges			$ 5,000	$ 5,000

Investments - Gross Unrealized

Investments - Gross Unrealized Gains and (Losses) Aggregated by Investment Category (Detail) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Schedule of Available-for-sale Securities [Line Items]
Investments, Cost	$ 209,453	$ 189,538
Investments, Gross Unrealized Gains	108	35
Investments, Gross Unrealized (Losses)	(127)	(110)
Investments, Estimated Fair Value	209,434	189,463
Time Deposits and Certificates of Deposit [Member]
Schedule of Available-for-sale Securities [Line Items]
Investments, Cost	9,756	23,818
Investments, Gross Unrealized Gains	1
Investments, Estimated Fair Value	9,757	23,818
Bankers Acceptance Drafts [Member]
Schedule of Available-for-sale Securities [Line Items]
Investments, Cost	5,330	1,439
Investments, Estimated Fair Value	5,330	1,439
Asset-Backed Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Investments, Cost	37,017	36,847
Investments, Gross Unrealized Gains	15	6
Investments, Gross Unrealized (Losses)	(42)	(44)
Investments, Estimated Fair Value	36,990	36,809
Commercial Paper [Member]
Schedule of Available-for-sale Securities [Line Items]
Investments, Cost	13,810	24,423
Investments, Gross Unrealized (Losses)	(60)	(42)
Investments, Estimated Fair Value	13,750	24,381
Corporate Obligations [Member]
Schedule of Available-for-sale Securities [Line Items]
Investments, Cost	77,788	46,700
Investments, Gross Unrealized Gains	58	21
Investments, Gross Unrealized (Losses)	(25)	(14)
Investments, Estimated Fair Value	77,821	46,707
Municipal Bonds [Member]
Schedule of Available-for-sale Securities [Line Items]
Investments, Cost	1,970	591
Investments, Estimated Fair Value	1,970	591
Promissory Note [Member]
Schedule of Available-for-sale Securities [Line Items]
Investments, Cost		675
Investments, Estimated Fair Value		675
U.S. Treasury Obligations [Member]
Schedule of Available-for-sale Securities [Line Items]
Investments, Cost	28,054	25,414
Investments, Gross Unrealized Gains	24
Investments, Estimated Fair Value	28,078	25,414
U.S. Agency Obligations [Member]
Schedule of Available-for-sale Securities [Line Items]
Investments, Cost	35,728	29,631
Investments, Gross Unrealized Gains	10	8
Investments, Gross Unrealized (Losses)		(10)
Investments, Estimated Fair Value	35,738	29,629
Group Insurance Contracts [Member] | Long Term Investments [Member]
Schedule of Available-for-sale Securities [Line Items]
Investments, Cost	6,006	5,432
Investments, Gross Unrealized Gains	249	126
Investments, Estimated Fair Value	$ 6,255	$ 5,558

Fair Value Measurements - Sched

Fair Value Measurements - Schedule of Fair Value of Assets and Liabilities Measured on Recurring Basis (Detail) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Restricted cash	$ 119	$ 5,287
Available-for-sale investments	209,434	189,463
Short-term investments	209,434	189,463
Derivatives - contracts		2,985
Pension assets	8,152
Other assets	37,883	32,467
Derivatives - liabilities		543
Interest Rate Hedge [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivatives - contracts	6,179	4,900
Derivatives - interest rate hedge - non-current	6,179	4,900
Fair Value Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total liabilities		559
Restricted cash - non-current	1,010	573
Total assets	275,775	255,935
Cash and cash equivalents	37,562	33,255
Restricted cash	119	5,287
Short-term investments	209,434	189,463
Derivatives - contracts	168	2,989
Total current assets	247,283	230,994
Available-for-sale investments	6,255	5,558
Other assets	22,237	19,383
Total long-term assets	28,492	24,941
Derivatives - liabilities	6,198	559
Fair Value Measurements, Recurring [Member] | Currency Forward Contracts [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivatives - contracts	168	2,985
Derivatives - liabilities	6,198	543
Fair Value Measurements, Recurring [Member] | Interest Rate Hedge [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivatives - interest rate hedge - non-current	6,179	4,900
Fair Value Measurements, Recurring [Member] | Options Contracts [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivatives - contracts		4
Derivatives - liabilities		16
Money Market Funds [Member] | Fair Value Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and cash equivalents	4,987	10,155
Restricted cash	119	5,287
Time Deposits and Certificates of Deposit [Member] | Fair Value Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and cash equivalents	2,100	4,900
Available-for-sale investments	9,757	23,818
Bankers Acceptance Drafts [Member] | Fair Value Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and cash equivalents		448
Available-for-sale investments	5,330	1,439
U.S. Agency Obligations [Member] | Fair Value Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and cash equivalents		3,899
Available-for-sale investments	35,738	29,629
Asset-Backed Securities [Member] | Fair Value Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale investments	36,990	36,809
U.S. Treasury Obligations [Member] | Fair Value Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale investments	28,078	25,414
Quoted Prices in Active Markets for Identical Assets or Liabilities (Level 1) [Member] | Fair Value Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Restricted cash - non-current	1,010	573
Total assets	6,116	16,015
Cash and cash equivalents	4,987	10,155
Restricted cash	119	5,287
Total current assets	5,106	15,442
Other assets	1,010	573
Total long-term assets	1,010	573
Quoted Prices in Active Markets for Identical Assets or Liabilities (Level 1) [Member] | Money Market Funds [Member] | Fair Value Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and cash equivalents	4,987	10,155
Restricted cash	119	5,287
Significant Other Observable Inputs (Level 2) [Member] | Fair Value Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total liabilities		559
Total assets	269,659	239,920
Cash and cash equivalents	32,575	23,100
Short-term investments	209,434	189,463
Derivatives - contracts	168	2,989
Total current assets	242,177	215,552
Available-for-sale investments	6,255	5,558
Other assets	21,227	18,810
Total long-term assets	27,482	24,368
Derivatives - liabilities	6,198	559
Significant Other Observable Inputs (Level 2) [Member] | Fair Value Measurements, Recurring [Member] | Currency Forward Contracts [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivatives - contracts	168	2,985
Derivatives - liabilities	6,198	543
Significant Other Observable Inputs (Level 2) [Member] | Fair Value Measurements, Recurring [Member] | Interest Rate Hedge [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivatives - interest rate hedge - non-current	6,179	4,900
Significant Other Observable Inputs (Level 2) [Member] | Fair Value Measurements, Recurring [Member] | Options Contracts [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivatives - contracts		4
Derivatives - liabilities		16
Significant Other Observable Inputs (Level 2) [Member] | Time Deposits and Certificates of Deposit [Member] | Fair Value Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and cash equivalents	2,100	4,900
Available-for-sale investments	9,757	23,818
Significant Other Observable Inputs (Level 2) [Member] | Bankers Acceptance Drafts [Member] | Fair Value Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and cash equivalents		448
Available-for-sale investments	5,330	1,439
Significant Other Observable Inputs (Level 2) [Member] | U.S. Agency Obligations [Member] | Fair Value Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and cash equivalents		3,899
Available-for-sale investments	35,738	29,629
Significant Other Observable Inputs (Level 2) [Member] | Asset-Backed Securities [Member] | Fair Value Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale investments	36,990	36,809
Significant Other Observable Inputs (Level 2) [Member] | U.S. Treasury Obligations [Member] | Fair Value Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale investments	28,078	25,414
Commercial Paper [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale investments	13,750	24,381
Commercial Paper [Member] | Fair Value Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and cash equivalents	30,475	11,828
Available-for-sale investments	13,750	24,381
Commercial Paper [Member] | Significant Other Observable Inputs (Level 2) [Member] | Fair Value Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and cash equivalents	30,475	11,828
Available-for-sale investments	13,750	24,381
Corporate Obligations [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale investments	77,821	46,707
Corporate Obligations [Member] | Fair Value Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and cash equivalents		2,025
Available-for-sale investments	77,821	46,707
Corporate Obligations [Member] | Significant Other Observable Inputs (Level 2) [Member] | Fair Value Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and cash equivalents		2,025
Available-for-sale investments	77,821	46,707
Municipal Bonds [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale investments	1,970	591
Municipal Bonds [Member] | Fair Value Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale investments	1,970	591
Municipal Bonds [Member] | Significant Other Observable Inputs (Level 2) [Member] | Fair Value Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale investments	1,970	591
Promissory Note [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale investments		675
Promissory Note [Member] | Fair Value Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale investments		675
Promissory Note [Member] | Significant Other Observable Inputs (Level 2) [Member] | Fair Value Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale investments		675
Group Insurance Contracts [Member] | Fair Value Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale investments	6,255	5,558
Group Insurance Contracts [Member] | Significant Other Observable Inputs (Level 2) [Member] | Fair Value Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale investments	6,255	5,558
Israeli Pension Assets [Member] | Fair Value Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Pension assets	15,048	13,910
Israeli Pension Assets [Member] | Significant Other Observable Inputs (Level 2) [Member] | Fair Value Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Pension assets	$ 15,048	$ 13,910

Fair Value Measurements - Sch56

Fair Value Measurements - Schedule of Fair Value of Assets and Liabilities Measured on Recurring Basis (Parenthetical) (Detail) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash/Non-negotiable time deposits - not subject to fair value disclosure requirements	$ 333,768	$ 228,623	$ 227,574	$ 305,437
Cash [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash/Non-negotiable time deposits - not subject to fair value disclosure requirements	292,808	192,432
Non-Negotiable Time Deposits [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash/Non-negotiable time deposits - not subject to fair value disclosure requirements	$ 3,398	$ 2,936

Derivatives - Additional Inform

Derivatives - Additional Information (Detail) - USD ($)	Sep. 30, 2016	Dec. 31, 2017	Dec. 31, 2016
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Maximum period for hedging a portion of forecasted foreign currency denominated intercompany sales of inventory		18 months
Gross notional values of outstanding forward foreign exchange contracts		$ 208,922,000	$ 120,208,000
Accumulated other comprehensive income realization period		12 months
Interest Rate Hedge [Member]
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Percentage of debt which is subject to interest rate swap fixed rate	50.00%
Interest rate swap agreement, credit spread rate		2.00%
Interest rate swap agreement, maturity date	Sep. 30, 2020
Interest rate swap agreement, notional amount		$ 305,000,000	335,000,000
Interest rate swap agreement, interest rate description		The Company entered into an interest rate swap agreement to fix the rate on approximately 50% of its then outstanding term loan balance, as described further in Note 13. This hedge fixes the interest rate paid on the hedged debt at 1.198% per annum plus the credit spread, which was 2.00% as of December 31, 2017, through September 30, 2020.
Interest rate swap agreement, fair value		$ 6,179,000	$ 4,900,000
Cash Flow Hedging [Member] | Interest Rate Hedge [Member]
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Interest rate swap agreement, interest rate	1.198%

Derivatives - Summary of Primar

Derivatives - Summary of Primary Net Hedging Positions and Corresponding Fair Values (Detail) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Derivative [Line Items]
Currency Hedged (Buy/Sell), Gross Notional Value, Net	$ 208,922	$ 120,208
Currency Hedged (Buy/Sell), Fair Value, (Liability)/Asset, Net	(6,030)	2,442
Forward Exchange Contracts [Member] | U.S. Dollar/Japanese Yen [Member]
Derivative [Line Items]
Currency Hedged (Buy/Sell), Gross Notional Value, Net	70,175	30,522
Currency Hedged (Buy/Sell), Fair Value, (Liability)/Asset, Net	(233)	763
Forward Exchange Contracts [Member] | U.S. Dollar/South Korean Won [Member]
Derivative [Line Items]
Currency Hedged (Buy/Sell), Gross Notional Value, Net	79,672	50,049
Currency Hedged (Buy/Sell), Fair Value, (Liability)/Asset, Net	(3,799)	1,342
Forward Exchange Contracts [Member] | U.S. Dollar/Euro [Member]
Derivative [Line Items]
Currency Hedged (Buy/Sell), Gross Notional Value, Net	26,140	18,040
Currency Hedged (Buy/Sell), Fair Value, (Liability)/Asset, Net	(1,047)	156
Forward Exchange Contracts [Member] | U.S. Dollar/U.K. Pound Sterling [Member]
Derivative [Line Items]
Currency Hedged (Buy/Sell), Gross Notional Value, Net	12,104	6,067
Currency Hedged (Buy/Sell), Fair Value, (Liability)/Asset, Net	(337)	117
Forward Exchange Contracts [Member] | U.S. Dollar/Taiwan Dollar [Member]
Derivative [Line Items]
Currency Hedged (Buy/Sell), Gross Notional Value, Net	20,831	15,530
Currency Hedged (Buy/Sell), Fair Value, (Liability)/Asset, Net	$ (614)	$ 64

Derivatives - Summary of Fair V

Derivatives - Summary of Fair Value Amounts of Company's Derivative Instruments (Detail) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Derivatives, Fair Value [Line Items]
Derivative assets		$ 2,985
Derivative liabilities		(543)
Total net derivative asset designated as hedging instruments	$ (6,030)	2,442
Derivatives Designated as Hedging Instruments [Member]
Derivatives, Fair Value [Line Items]
Total net derivative asset designated as hedging instruments	149	7,342
Foreign Exchange Contracts [Member]
Derivatives, Fair Value [Line Items]
Derivative assets	168
Derivative liabilities	(6,198)
Foreign Exchange Contracts [Member] | Derivatives Designated as Hedging Instruments [Member]
Derivatives, Fair Value [Line Items]
Derivative assets	168	2,985
Derivative liabilities	(6,198)	(543)
Interest Rate Hedge [Member]
Derivatives, Fair Value [Line Items]
Derivative assets	6,179	4,900
Interest Rate Hedge [Member] | Derivatives Designated as Hedging Instruments [Member]
Derivatives, Fair Value [Line Items]
Derivative assets	$ 6,179	$ 4,900

Derivatives - Summary of Fair60

Derivatives - Summary of Fair Value Amounts of Company's Derivative Instruments (Parenthetical) (Detail) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Derivatives, Fair Value [Line Items]
Derivative asset classified in other current assets		$ 2,985
Derivative liability classified in other current liabilities		(543)
Foreign Exchange Contracts [Member]
Derivatives, Fair Value [Line Items]
Derivative asset classified in other current assets	$ 168
Derivative liability classified in other current liabilities	(6,198)
Interest Rate Hedge [Member]
Derivatives, Fair Value [Line Items]
Derivative asset classified in other current assets	$ 6,179	$ 4,900

Derivatives - Summary of (Losse

Derivatives - Summary of (Losses) Gains on Derivatives Designated as Cash Flow Hedging Instruments (Detail) - Forward Exchange Contracts [Member] - Cash Flow Hedging [Member] - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Derivative Instruments, Gain (Loss) [Line Items]
Net (loss) gain recognized in OCI	$ (6,036)	$ 5,914	$ (3,748)
Net (loss) gain reclassified from accumulated OCI into income	$ (2,685)	$ (1,414)	$ 3,520

Derivatives - Summary of Losses

Derivatives - Summary of Losses on Derivatives Not Designated as Cash Flow Hedging Instruments (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Forward Exchange Contracts [Member]
Derivative Instruments Gain Loss Not Designated As Hedging Instruments [Line Items]
Net loss recognized in income	$ (3,416)	$ (31)	$ (40)

Inventories - Summary of Invent

Inventories - Summary of Inventories (Detail) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Inventory Disclosure [Abstract]
Raw material	$ 191,351	$ 150,150
Work-in-process	54,050	39,105
Finished goods	93,680	86,614
Inventories	$ 339,081	$ 275,869

Inventories - Additional Inform

Inventories - Additional Information (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Inventory Disclosure [Abstract]
Inventory related excess and obsolete charges	$ 20,213	$ 16,039	$ 13,602

Property, Plant and Equipment -

Property, Plant and Equipment - Summary of Property, Plant and Equipment (Detail) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Property, Plant and Equipment [Line Items]
Property, plant and equipment	$ 657,143	$ 618,041
Less: accumulated depreciation	485,361	443,482
Property, plant and equipment, net	171,782	174,559
Land [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment	11,650	11,115
Buildings [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment	103,563	100,169
Machinery and Equipment [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment	317,073	297,342
Furniture and Fixtures, Office Equipment and Software [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment	145,945	139,392
Leasehold Improvements [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment	65,293	63,431
Construction in Progress [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment	$ 13,619	$ 6,592

Property, Plant and Equipment66

Property, Plant and Equipment - Additional Information (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Property, Plant and Equipment [Abstract]
Depreciation of property, plant and equipment	$ 36,813	$ 30,245	$ 15,339

Acquisitions and Dispositions -

Acquisitions and Dispositions - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Thousands	Apr. 29, 2016	Mar. 17, 2015	Jul. 31, 2017	Apr. 30, 2017	Apr. 30, 2016	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Business Acquisition [Line Items]
Business acquisition share price	$ 23
Stock-based compensation expense														$ 24,378	$ 25,228	$ 13,013
Total proceeds from sale of business unit, net of cash sold				$ 72,509										72,509
Pre-tax gain				$ 74,856										74,856
Net revenues						$ 511,800	$ 486,267	$ 480,757	$ 437,153	$ 405,140	$ 380,660	$ 325,861	$ 183,681	1,915,977	1,295,342	813,524
Payments to acquire business, net of cash acquired															939,591	$ 9,910
Data Analytics Solutions Business [Member]
Business Acquisition [Line Items]
Net revenues															12,700
Minority Interest in Private Company [Member]
Business Acquisition [Line Items]
Investments in minority interest			$ 100		$ 9,300
Impairment charges										$ 5,000					5,000
Newport [Member]
Business Acquisition [Line Items]
Business acquisition share price	$ 23
Fair value write-up of acquired finished goods inventory						15,090								15,090
Incremental costs of sales charge															15,090
Fair value write-up of acquired property, plant and equipment						$ 36,242								$ 36,242
Compensation expense															6,635
Stock-based compensation expense															$ 3,334
Payments to acquire business, net of cash acquired	$ 945,815
Business acquisition, cash acquired	$ 61,463
Precisive, LLC [Member]
Business Acquisition [Line Items]
Payments to acquire business, net of cash acquired		$ 12,085
Business acquisition, cash acquired		435
Business acquisition, deferred consideration payment		$ 2,600

Acquisitions and Dispositions68

Acquisitions and Dispositions - Summary of Purchase Price (Detail) - USD ($) $ in Thousands	Apr. 29, 2016	Dec. 31, 2016	Dec. 31, 2015
Business Acquisition [Line Items]
Total purchase price, net of cash and cash equivalents acquired		$ 939,591	$ 9,910
Newport [Member]
Business Acquisition [Line Items]
Cash paid for outstanding shares	$ 905,254
Settlement of share-based compensation awards	8,824
Cash paid for Newport debt	93,200
Total purchase price	1,007,278
Less: cash and cash equivalents acquired	(61,463)
Total purchase price, net of cash and cash equivalents acquired	$ 945,815

Acquisitions and Dispositions69

Acquisitions and Dispositions - Summary of Purchase Price (Parenthetical) (Detail)	Apr. 29, 2016$ / sharesshares
Business Combinations [Abstract]
Business acquisition share price | $ / shares	$ 23
Business acquisition number of shares acquired | shares	39,359,000

Acquisitions and Dispositions70

Acquisitions and Dispositions - Summary of Estimated Fair Value of Assets Acquired and Liabilities Assumed (Detail) - USD ($) $ in Thousands	Apr. 29, 2016	Mar. 17, 2015	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2017
Business Acquisition [Line Items]
Goodwill			$ 588,585	$ 199,703	$ 591,047
Total purchase price, net of cash and cash equivalents acquired			939,591	$ 9,910
Newport [Member]
Business Acquisition [Line Items]
Current assets (including cash)	$ 186,137
Inventory	142,714
Intangible assets	404,506
Goodwill	396,027		$ 396,027
Property, plant and equipment	119,932
Long-term assets	22,725
Total assets acquired	1,272,041
Current liabilities	95,156
Intangible liability	4,302
Other long-term liabilities	165,305
Total liabilities assumed	264,763
Fair value of assets acquired and liabilities assumed	1,007,278
Less: cash and cash equivalents acquired	(61,463)
Total purchase price, net of cash and cash equivalents acquired	$ 945,815
Precisive, LLC [Member]
Business Acquisition [Line Items]
Current assets (including cash)		$ 693
Non-current assets		18
Intangible assets		5,110
Goodwill		7,042
Total assets acquired		12,863
Current liabilities		343
Fair value of assets acquired and liabilities assumed		12,520
Less: cash and cash equivalents acquired		(435)
Total purchase price, net of cash and cash equivalents acquired		$ 12,085

Acquisitions and Dispositions71

Acquisitions and Dispositions - Allocation of Acquired Intangible Assets and Liabilities Related Estimates of Useful Lives (Detail) - USD ($) $ in Thousands	Apr. 29, 2016	Mar. 17, 2015	Mar. 17, 2015	Dec. 31, 2017	Dec. 31, 2016
Acquired Finite-Lived Intangible Assets [Line Items]
Acquired intangible assets, purchase price	$ 404,506
Minimum [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Estimated useful life of finite-lived intangible assets				1 year
Maximum [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Estimated useful life of finite-lived intangible assets				18 years
Newport [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Acquired intangible assets, purchase price					$ 404,506
Precisive, LLC [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Acquired intangible assets, purchase price		$ 5,110
Order Backlog [Member] | Newport [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Acquired intangible assets, purchase price	$ 12,100
Estimated useful life of finite-lived intangible assets	1 year
Order Backlog [Member] | Precisive, LLC [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Acquired intangible assets, purchase price		50
Estimated useful life of finite-lived intangible assets			18 months
Customer Relationships [Member] | Newport [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Acquired intangible assets, purchase price	$ 247,793				$ 247,793
Customer Relationships [Member] | Newport [Member] | Minimum [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Estimated useful life of finite-lived intangible assets	6 years
Customer Relationships [Member] | Newport [Member] | Maximum [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Estimated useful life of finite-lived intangible assets	18 years
Customer Relationships [Member] | Precisive, LLC [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Acquired intangible assets, purchase price		1,430
Estimated useful life of finite-lived intangible assets			8 years
Trademarks and Trade Names [Member] | Newport [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Acquired intangible assets, purchase price	$ 55,900
Estimated useful life of finite-lived intangible assets	Indefinite
Developed Technology [Member] | Newport [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Acquired intangible assets, purchase price	$ 75,386
Developed Technology [Member] | Newport [Member] | Minimum [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Estimated useful life of finite-lived intangible assets	4 years
Developed Technology [Member] | Newport [Member] | Maximum [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Estimated useful life of finite-lived intangible assets	8 years
Developed Technology [Member] | Precisive, LLC [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Acquired intangible assets, purchase price		820
Estimated useful life of finite-lived intangible assets			10 years
In-process Research and Development [Member] | Newport [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Acquired intangible assets, purchase price	$ 6,899
Estimated useful life of finite-lived intangible assets	Undefined
Leasehold Interest Favorable [Member] | Newport [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Acquired intangible assets, purchase price	$ 6,428
Leasehold Interest Favorable [Member] | Newport [Member] | Minimum [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Estimated useful life of finite-lived intangible assets	4 years
Leasehold Interest Favorable [Member] | Newport [Member] | Maximum [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Estimated useful life of finite-lived intangible assets	5 years
Leasehold Interest Unfavorable [Member] | Newport [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Acquired intangible assets, purchase price	$ 4,302
Exclusive Patent License [Member] | Precisive, LLC [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Acquired intangible assets, purchase price		2,600
Estimated useful life of finite-lived intangible assets			10 years
Trade names [Member] | Precisive, LLC [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Acquired intangible assets, purchase price		$ 210
Estimated useful life of finite-lived intangible assets			10 years

Acquisitions and Dispositions72

Acquisitions and Dispositions - Schedule of Unaudited Pro Forma Financial Information (Detail) - Newport [Member] - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015
Business Acquisition [Line Items]
Total net revenues	$ 1,475,637	$ 1,412,748
Net income	$ 111,076	$ 69,096
Net income per share:
Basic	$ 2.08	$ 1.30
Diluted	$ 2.06	$ 1.29

Goodwill and Intangible Asset73

Goodwill and Intangible Assets - Goodwill (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016
Goodwill and Intangible Assets Disclosure [Abstract]
Beginning balance, Goodwill Gross Carrying Amount	$ 727,999	$ 339,117
Acquired goodwill, Gross Carrying Amount		396,027
Sale of business, Gross Carrying Amount	(3,115)
Foreign currency translation, Gross Carrying Amount	10,439	(7,145)
Ending balance, Goodwill Gross Carrying Amount	735,323	727,999
Beginning balance, Accumulated Impairment (Loss)	(139,414)	(139,414)
Acquired goodwill, Accumulated Impairment (Loss)	0	0
Impairment loss, Accumulated Impairment (Loss)	(4,862)
Foreign currency translation, Accumulated Impairment (Loss)	0	0
Ending balance, Accumulated Impairment (Loss)	(144,276)	(139,414)
Beginning balance, Goodwill Net	588,585	199,703
Acquired goodwill, Net		396,027
Sale of business, Net	(3,115)
Impairment loss, Net	(4,862)
Foreign currency translation, Net	10,439	(7,145)
Ending balance, Goodwill Net	$ 591,047	$ 588,585

Goodwill and Intangible Asset74

Goodwill and Intangible Assets - Goodwill (Parenthetical) (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Apr. 29, 2016	Dec. 31, 2015
Goodwill [Line Items]
Goodwill	$ 591,047	$ 588,585		$ 199,703
Goodwill related to the sale of business unit	3,115
Goodwill impairment loss	4,862
Data Analytics Solutions Business [Member]
Goodwill [Line Items]
Goodwill related to the sale of business unit	$ 3,115
Newport [Member]
Goodwill [Line Items]
Goodwill		$ 396,027	$ 396,027

Goodwill and Intangible Asset75

Goodwill and Intangible Assets - Additional Information (Detail) - USD ($)	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Goodwill and Intangible Assets Disclosure [Abstract]
Impairment charges	$ 1,511,000	$ 0	$ 0
Amortization of intangible assets	45,743,000	35,681,000	$ 6,764,000
Amortization income from unfavorable lease commitments	$ 811,000	$ 569,000

Goodwill and Intangible Asset76

Goodwill and Intangible Assets - Intangible Assets (Detail) - USD ($)	Apr. 29, 2016	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Finite-Lived Intangible Assets [Line Items]
Intangible assets, Gross		$ 565,698,000	$ 573,353,000
Impairment Charges		(1,511,000)	0	$ 0
Accumulated Amortization		(199,619,000)	(160,813,000)
Foreign Currency Translation		1,830,000	(4,536,000)
Intangible assets, net		366,398,000	408,004,000
Acquired intangible assets	$ 404,506,000
Newport [Member]
Finite-Lived Intangible Assets [Line Items]
Acquired intangible assets			404,506,000
Completed Technology [Member]
Finite-Lived Intangible Assets [Line Items]
Intangible assets, Gross		172,431,000	176,586,000
Impairment Charges		(105,000)
Accumulated Amortization		(115,371,000)	(97,707,000)
Foreign Currency Translation		333,000	(1,068,000)
Intangible assets, net		57,288,000	77,811,000
Completed Technology [Member] | Newport [Member]
Finite-Lived Intangible Assets [Line Items]
Acquired intangible assets			75,386,000
Customer Relationships [Member]
Finite-Lived Intangible Assets [Line Items]
Intangible assets, Gross		282,744,000	285,044,000
Impairment Charges		(1,406,000)
Accumulated Amortization		(45,518,000)	(29,709,000)
Foreign Currency Translation		1,571,000	(3,404,000)
Intangible assets, net		237,391,000	251,931,000
Customer Relationships [Member] | Newport [Member]
Finite-Lived Intangible Assets [Line Items]
Acquired intangible assets	$ 247,793,000		247,793,000
Patents, Trademarks, Trade Names and Other [Member]
Finite-Lived Intangible Assets [Line Items]
Intangible assets, Gross		110,523,000	111,723,000
Accumulated Amortization		(38,730,000)	(33,397,000)
Foreign Currency Translation		(74,000)	(64,000)
Intangible assets, net		$ 71,719,000	78,262,000
Patents, Trademarks, Trade Names and Other [Member] | Newport [Member]
Finite-Lived Intangible Assets [Line Items]
Acquired intangible assets			$ 81,327,000

Goodwill and Intangible Asset77

Goodwill and Intangible Assets - Intangible Assets (Parenthetical) (Detail) - USD ($) $ in Thousands	Apr. 29, 2016	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Finite-Lived Intangible Assets [Line Items]
Amortization of intangible assets		$ 45,743	$ 35,681	$ 6,764
Acquired intangible assets	$ 404,506
Completed Technology [Member] | Data Analytics Solutions Business [Member]
Finite-Lived Intangible Assets [Line Items]
Amortization of intangible assets		4,155
Customer Relationships [Member] | Data Analytics Solutions Business [Member]
Finite-Lived Intangible Assets [Line Items]
Amortization of intangible assets		2,300
Patents, Trademarks, Trade Names and Other [Member] | Data Analytics Solutions Business [Member]
Finite-Lived Intangible Assets [Line Items]
Amortization of intangible assets		$ 1,200
Newport [Member]
Finite-Lived Intangible Assets [Line Items]
Acquired intangible assets			404,506
Unfavorable lease commitments			4,302
Newport [Member] | Completed Technology [Member]
Finite-Lived Intangible Assets [Line Items]
Acquired intangible assets			75,386
Newport [Member] | Customer Relationships [Member]
Finite-Lived Intangible Assets [Line Items]
Acquired intangible assets	$ 247,793		247,793
Newport [Member] | Patents, Trademarks, Trade Names and Other [Member]
Finite-Lived Intangible Assets [Line Items]
Acquired intangible assets			$ 81,327

Goodwill and Intangible Asset78

Goodwill and Intangible Assets - Estimated Net Amortization Expense (Detail) $ in Thousands	Dec. 31, 2017USD ($)
Goodwill and Intangible Assets Disclosure [Abstract]
2,018	$ 43,404
2,019	40,333
2,020	28,262
2,021	20,464
2,022	17,703
Thereafter	$ 157,360

Product Warranties - Product Wa

Product Warranties - Product Warranty Activities (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016
Guarantees [Abstract]
Beginning balance	$ 8,261	$ 5,205
Product warranty liability from Newport Merger		3,040
Provisions for product warranties	15,884	8,858
Direct and other charges to warranty liability	(14,041)	(8,842)
Ending balance	$ 10,104	$ 8,261

Product Warranties - Product 80

Product Warranties - Product Warranty Activities (Parenthetical) (Detail) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Guarantees [Abstract]
Short-term product warranty	$ 9,719	$ 8,200
Long-term product warranty	$ 385	$ 61

Debt - Additional Information (

Debt - Additional Information (Detail)

Jun. 06, 2017

Dec. 14, 2016

Sep. 30, 2016USD ($)

Jun. 09, 2016USD ($)

Sep. 30, 2016USD ($)

Dec. 31, 2017USD ($)Institution

Dec. 31, 2016USD ($)

Nov. 30, 2017USD ($)

Aug. 31, 2017USD ($)

Jul. 31, 2017USD ($)

Mar. 31, 2017USD ($)

Nov. 30, 2016USD ($)

Debt Instrument [Line Items]

Leverage ratio

1.25%

1.25%

Applicable margin for Term Loan Credit agreement

2.25%

LIBOR floor rate

0.75%

2.00%

Decrease in base rate borrowings margin

1.25%

Description of applicable margin

The Re-pricing Amendment 3 decreased the applicable margin for the Company’s term loan under the Credit Agreement to 2.25% for LIBOR rate loans when the Total Leverage Ratio (as defined in the Credit Agreement) was at or above 1.25:1 and decreased to 2.00% when the Total Leverage Ratio was below 1.25:1, both with a LIBOR floor of 0.75%. The margin for base rate borrowings decreased to 1.25% when the Total Leverage Ratio is at or above 1.25:1 and to 1.00% when the Total Leverage Ratio is below 1.25:1.

Interest expense

$ 30,990,000

$ 30,611,000

Interest Rate Hedge [Member]

Debt Instrument [Line Items]

Interest rate swap agreement, maturity date

Sep. 30, 2020

Interest rate swap agreement, notional amount

$ 305,000,000

335,000,000

Interest rate swap agreement, credit spread rate

2.00%

Austria [Member]

Debt Instrument [Line Items]

Interest on loans payable

Semi-annually

Japan [Member]

Debt Instrument [Line Items]

Borrowing capacity in the form of letters of credit

$ 20,410,000

Number of financial institutions for available lines of credit and borrowing arrangements | Institution

2

Aggregate borrowings expire and renewed

3 month intervals

Total borrowings outstanding

$ 0

0

Minimum [Member] | Austria [Member]

Debt Instrument [Line Items]

Loan interest rate

0.75%

Maximum [Member] | Austria [Member]

Debt Instrument [Line Items]

Loan interest rate

2.00%

Revolving Lines of Credit [Member]

Debt Instrument [Line Items]

Borrowing capacity in the form of letters of credit

$ 11,092,000

Revolving Lines of Credit [Member] | Base Rate [Member]

Debt Instrument [Line Items]

Line of credit base interest rate

1.25%

Newport [Member] | Revolving Lines of Credit [Member]

Debt Instrument [Line Items]

Total borrowings outstanding

$ 2,965,000

$ 4,703,000

Newport [Member] | Term Loan Credit Agreement [Member] | Secured Debt [Member]

Debt Instrument [Line Items]

Secured term loan, face amount

$ 780,000,000

Debt instrument, interest rate terms

Borrowings under the Term Loan Facility bear interest per annum at one of the following rates selected by the Company: (a) a base rate determined by reference to the highest of (1) the federal funds effective rate plus 0.50%, (2) the “prime rate” quoted in The Wall Street Journal, (3) a LIBOR rate determined by reference to the costs of funds for U.S. dollar deposits for an interest period of one month adjusted for certain additional costs, plus 1.00%, and (4) a floor of 1.75%, plus, in each case, an applicable margin based on the Company’s leverage ratio (1.25% as of December 31, 2017); or (b) a LIBOR rate determined by reference to the costs of funds for U.S. dollar deposits for the interest period relevant to such borrowing adjusted for certain additional costs, subject to a LIBOR rate floor of 0.75%, plus an applicable margin based on our leverage ratio (2.00% as of December 31, 2017). The Company has elected the interest rate as described in clause (b). The Credit Agreement provides that all loans will be determined by reference to the Base Rate if the LIBOR rate cannot be ascertained, if regulators impose material restrictions on the authority of a lender to make LIBOR rate loans, and for other reasons. The Term Loan Facility was issued with original issue discount of 1.00% of the principal amount thereof.

Debt instrument, issue discount percentage on principal

1.00%

Newport [Member] | Term Loan Credit Agreement [Member] | Secured Debt [Member] | Federal Funds Rate [Member]

Debt Instrument [Line Items]

Debt instrument, interest rate

0.50%

Newport [Member] | Term Loan Credit Agreement [Member] | Secured Debt [Member] | Adjusted One Month LIBOR [Member]

Debt Instrument [Line Items]

Debt instrument, interest rate

1.00%

Period of Libor measurement

1 month

Newport [Member] | Term Loan Credit Agreement [Member] | Secured Debt [Member] | Floor Rate [Member]

Debt Instrument [Line Items]

Debt instrument, interest rate

1.75%

Leverage ratio

1.25%

Newport [Member] | Term Loan Credit Agreement [Member] | Secured Debt [Member] | LIBOR Floor Rate [Member]

Debt Instrument [Line Items]

Debt instrument, interest rate

0.75%

Leverage ratio

2.00%

Newport [Member] | Term Loan Credit Agreement [Member] | Secured Debt Repricing Amendment 1 [Member]

Debt Instrument [Line Items]

Debt instrument, interest rate

2.50%

Debt instrument, pre-payment premium percentage

1.00%

Debt instrument, pre-payment premium

$ 7,300,000

Debt instrument, prepaid principal amount

$ 50,000,000

Debt instrument, prepaid amount

$ 60,000,000

Deferred finance fees, original issue discount and re-pricing fee, gross

$ 28,747,000

Deferred finance fees, original issue discount and re-pricing fee, net

9,185,000

Newport [Member] | Term Loan Credit Agreement [Member] | Secured Debt Repricing Amendment 1 [Member] | Interest Rate Hedge [Member]

Debt Instrument [Line Items]

Interest rate swap agreement, maturity date

Sep. 30, 2020

Interest rate swap agreement, notional amount

$ 335,000,000

$ 335,000,000

$ 305,000,000

Interest rate swap agreement, interest rate

1.198%

1.198%

Interest rate swap agreement, credit spread rate

2.00%

Newport [Member] | Term Loan Credit Agreement [Member] | Secured Debt Repricing Amendment 1 [Member] | Maximum [Member]

Debt Instrument [Line Items]

Debt instrument, quarterly payment percentage

0.25

Newport [Member] | Term Loan Credit Agreement [Member] | Secured Debt Repricing Amendment 1 [Member] | LIBOR [Member]

Debt Instrument [Line Items]

Debt instrument, interest rate

3.50%

Newport [Member] | Term Loan Credit Agreement [Member] | Secured Debt Repricing Amendment 2 [Member]

Debt Instrument [Line Items]

Secured term loan, face amount

$ 398,464,000

Debt instrument, prepaid principal amount

375,000,000

$ 50,000,000

$ 75,000,000

$ 50,000,000

$ 50,000,000

$ 40,000,000

Debt instrument, scheduled principal payments

6,536,000

Newport [Member] | Term Loan Credit Agreement [Member] | Secured Debt Repricing Amendment 2 [Member] | LIBOR [Member]

Debt Instrument [Line Items]

Debt instrument, interest rate

2.75%

Newport [Member] | Term Loan Credit Agreement [Member] | Secured Debt Repricing Amendment 2 [Member] | Base Rate [Member]

Debt Instrument [Line Items]

Debt instrument, interest rate

1.75%

Newport [Member] | Asset Based Credit Agreement [Member]

Debt Instrument [Line Items]

Debt issuance cost capitalized

$ 1,201,000

Contractual term

5 years

Newport [Member] | Asset Based Credit Agreement [Member] | Secured Debt [Member]

Debt Instrument [Line Items]

Secured term loan, face amount

$ 50,000,000

Debt instrument, interest rate terms

Borrowings under the ABL Facility bear interest per annum at one of the following rates selected by the Company: (a) a base rate determined by reference to the highest of (1) the federal funds effective rate plus 0.50%, (2) the “prime rate” quoted in The Wall Street Journal, and (3) a LIBOR rate determined by reference to the costs of funds for U.S. dollar deposits for an interest period of one month adjusted for certain additional costs, plus 1.00%, plus, in each case, an initial applicable margin of 0.75%; and (b) a LIBOR rate determined by reference to the costs of funds for U.S. dollar deposits for the interest period relevant to such borrowing adjusted for certain additional costs, plus an initial applicable margin of 1.75%.

Percentage of borrowing based on eligible accounts

85.00%

Percentage of borrowing based on lower of cost or market value of certain eligible inventory

65.00%

Percentage of borrowing based on net orderly liquidation value of certain eligible inventory

85.00%

Percentage of borrowing base

30.00%

Initial commitment fee percentage

0.375%

Total commitment fee recognized in interest expense

$ 242,000

Newport [Member] | Asset Based Credit Agreement [Member] | Secured Debt [Member] | Maximum [Member]

Debt Instrument [Line Items]

Percentage of borrowing based on book value of certain eligible accounts

70.00%

Newport [Member] | Asset Based Credit Agreement [Member] | Secured Debt [Member] | Federal Funds Rate [Member]

Debt Instrument [Line Items]

Debt instrument, interest rate

0.50%

Newport [Member] | Asset Based Credit Agreement [Member] | Secured Debt [Member] | Adjusted One Month LIBOR [Member]

Debt Instrument [Line Items]

Debt instrument, interest rate

1.00%

Period of Libor measurement

1 month

Newport [Member] | Asset Based Credit Agreement [Member] | Secured Debt [Member] | LIBOR [Member]

Debt Instrument [Line Items]

Debt instrument, interest rate

1.75%

Newport [Member] | Asset Based Credit Agreement [Member] | Secured Debt [Member] | Initial Margin Rate [Member]

Debt Instrument [Line Items]

Debt instrument, interest rate

0.75%

Newport [Member] | Asset Based Credit Agreement [Member] | Letter of Credit [Member]

Debt Instrument [Line Items]

Borrowing capacity in the form of letters of credit

$ 15,000,000

Debt - Schedule of Short Term D

Debt - Schedule of Short Term Debt (Detail) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Short-term Debt [Line Items]
Short term debt	$ 2,972	$ 10,993
Short term debt		6,282
Short term debt	2,972	10,993
Other Debt [Member]
Short-term Debt [Line Items]
Short term debt	7	8
Japan [Member] | Line of Credit [Member]
Short-term Debt [Line Items]
Short term debt	2,750	4,245
Japan [Member] | Receivables Financing Facility [Member]
Short-term Debt [Line Items]
Short term debt	$ 215	$ 458

Debt - Schedule of Long Term De

Debt - Schedule of Long Term Debt (Detail) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Debt Instrument [Line Items]
Long term debt	$ 389,993	$ 601,229
Term Loan Facility, Net [Member]
Debt Instrument [Line Items]
Long term debt	389,279	600,681
Austria [Member] | Loans Due Through March 2020 [Member]
Debt Instrument [Line Items]
Long term debt	$ 714	$ 548

Debt - Schedule of Long Term 84

Debt - Schedule of Long Term Debt (Parenthetical) (Detail) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Term Loan Facility, Net [Member]
Debt Instrument [Line Items]
Deferred financing fees, original issuance discount and re-pricing fee	$ 9,185	$ 19,642

Debt - Schedule of Contractual

Debt - Schedule of Contractual Maturities of Debt Obligations (Detail) $ in Thousands	Dec. 31, 2017USD ($)
Maturities of Long-term Debt [Abstract]
2,018	$ 2,972
2,019	639
2,020	75
2,021	0
2,022	0
Thereafter	$ 398,464

Income Taxes - Reconciliation o

Income Taxes - Reconciliation of Company's Effective Tax Rate to U.S. Federal Statutory Rate (Detail)	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Income Tax Disclosure [Abstract]
U.S. Federal income tax statutory rate	35.00%	35.00%	35.00%
Federal tax credits	(0.70%)	(1.80%)	(1.20%)
State income taxes, net of federal benefit	1.00%	0.80%	1.30%
Effect of foreign operations taxed at various rates	(12.10%)	(12.70%)	(6.40%)
Qualified production activity tax benefit	(1.40%)	(2.90%)	(1.60%)
Transition tax, net of foreign tax credits	6.40%
Revaluation of US deferred income taxes	(5.00%)
Stock based compensation	(2.50%)
Deferred tax asset valuation allowance	(0.10%)	2.10%
Release of income tax reserves (including interest)	(0.40%)	(2.40%)	(4.80%)
Foreign dividends, net of foreign tax credits	3.30%	(2.20%)	0.70%
Acquisition and integration related costs		1.50%
Other	0.70%	0.70%	0.30%
Total	24.20%	18.10%	23.30%

Income Taxes - Components of In

Income Taxes - Components of Income from Operations Before Income Taxes and Related Provision for Income Taxes (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Income from continuing operations before income taxes:
United States	$ 224,979	$ 42,491	$ 90,401
Foreign	222,646	85,486	69,067
Income from continuing operations before income taxes	447,625	127,977	159,468
Current taxes:
United States	77,023	17,693	15,813
State	6,149	2,359	2,927
Foreign	30,152	41,938	18,021
Current taxes, Total	113,324	61,990	36,761
Deferred taxes:
United States			(862)
State and Foreign	11,419	(15,218)	1,272
Deferred taxes, Total	(4,831)	(38,822)	410
Provision for income taxes	$ 108,493	$ 23,168	$ 37,171

Income Taxes - Significant Comp

Income Taxes - Significant Components of Deferred Tax Assets and Deferred Tax Liabilities (Detail) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Deferred tax assets:
Carry-forward losses and credits	$ 25,834	$ 50,673
Inventory and warranty reserves	17,734	24,253
Accrued expenses and other reserves	15,393	16,176
Stock-based compensation	5,092	8,995
Executive supplemental retirement benefits	4,984	6,888
Other	597
Total deferred tax assets	69,634	106,985
Deferred tax liabilities:
Acquired intangible assets	(83,092)	(127,571)
Depreciation and amortization	(10,150)	(16,428)
Loan costs	(2,157)	(7,282)
Foreign withholding taxes	(16,206)
Unrealized gain	(469)	(3,195)
Other		(1,336)
Total deferred tax liabilities	(112,074)	(155,812)
Valuation allowance	(13,629)	(12,527)	$ (6,127)
Net deferred tax (liabilities) assets	$ (56,069)	$ (61,354)

Income Taxes - Additional Infor

Income Taxes - Additional Information (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Income Taxes [Line Items]
Decrease in deferred tax liabilities	$ 22,345
Gross tax research other tax credit carryforwards	36,496
Gross unrecognized tax benefits excluding interest and penalties	27,345	$ 25,465	$ 4,332	$ 19,610
Net unrecognized tax benefit excluding interest and penalties that would impact effective tax rate	18,276
Net benefit to income tax expense, excluding interest and penalties, due to discrete reserve releases	3,100
Accrued interest on unrecognized tax benefits	327	491	157
Net unrecognized tax benefits, excluding interest and penalties, related to foreign tax positions	$ 1,025
Income tax examination, description	The U.S. statute of limitations remains open for tax years 2014 through present. The statute of limitations for the Company’s tax filings in other jurisdictions varies between fiscal years 2012 through the present. The Company also has certain federal credit carry-forwards and state tax loss and credit carry-forwards that are open to examination for tax years 2000 through the present.
Change in valuation allowance	$ 1,102	$ 6,400	$ (20,636)
Undistributed earnings of foreign subsidiaries	560,000
Tax expense related to repatriation of foreign earnings	$ 27,610
Minimum [Member]
Income Taxes [Line Items]
Income tax holiday tax rate	7.50%
Maximum [Member]
Income Taxes [Line Items]
Income tax holiday tax rate	16.00%
Indefinite [Member]
Income Taxes [Line Items]
Gross tax research other tax credit carryforwards	$ 12,559
Federal State and Foreign [Member]
Income Taxes [Line Items]
Tax credit expiration period	2,035
Federal State and Foreign [Member] | Indefinite [Member]
Income Taxes [Line Items]
Operating loss carry forwards	$ 43,431
Federal State and Foreign [Member] | 2017 [Member]
Income Taxes [Line Items]
Operating loss carry forwards	$ 37,098
Earliest Tax Year [Member]
Income Taxes [Line Items]
Open tax year	2,014

Income Taxes - Reconciliation90

Income Taxes - Reconciliation of Beginning and Ending Amount of Gross Unrecognized Tax Benefits (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Income Tax Disclosure [Abstract]
Balance at beginning of year	$ 25,465	$ 4,332	$ 19,610
Decreases for prior years	640	(195)	(26)
Increases for the current year	4,340	23,940	322
Reductions related to settlements with taxing authorities			(15,370)
Reductions related to expiration of statute of limitations	(3,100)	(2,612)	(204)
Balance at end of year	$ 27,345	$ 25,465	$ 4,332

Stockholders' Equity - Addition

Stockholders' Equity - Additional Information (Detail) - USD ($)	Feb. 12, 2018	Jul. 25, 2011	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Stockholders Equity [Line Items]
Common stock, value of shares authorized to repurchase		$ 200,000,000
Stock repurchase, shares		1,770,000									0	44,798
Value of shares repurchased		$ 52,000,000										$ 1,545,000	$ 13,294,000
Average price of repurchased shares												$ 34.50
Cash dividends per common share			$ 0.180	$ 0.175	$ 0.175	$ 0.175	$ 0.170	$ 0.170	$ 0.170	$ 0.170	$ 0.71	$ 0.68	$ 0.68
Dividend payment to common shareholders			$ 38,178,000	$ 38,178,000	$ 38,178,000	$ 38,178,000	$ 36,361,000	$ 36,361,000	$ 36,361,000	$ 36,361,000	$ 38,178,000	$ 36,361,000	$ 35,969,000
Subsequent Event [Member]
Stockholders Equity [Line Items]
Dividend declared date	Feb. 12, 2018
Cash dividend to be paid	$ 0.18
Dividend to be paid date	Mar. 9, 2018
Dividend declared, shareholders of record date	Feb. 26, 2018

Stock-Based Compensation - Addi

Stock-Based Compensation - Additional Information (Detail) - USD ($)	Jun. 01, 2017	Jan. 31, 2017	Apr. 29, 2016	May 31, 2017	May 31, 2016	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock, shares issued						54,355,535	53,672,861
Common stock reserved for issuance						18,000,000
Vesting period						3 years
Number of stock options outstanding						0	0
Tax benefit realized from stock-based plans							$ 1,254,000	$ 837,000
Capitalization of share based payment costs						$ 471,000	$ 471,000
Options granted						0	0	0
Total intrinsic value of options exercised								$ 494,000
Restricted stock units, weighted average grant date fair value						$ 13.14	$ 8.52	$ 8.16
Employee Stock Option [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of stock options outstanding						0	0
Cash received from employees as a result of employee stock option exercises								$ 592,000
Tax benefit realized from stock-based plans								$ 21,000
Number of stock options exercisable						0	0
Stock Incentive Plan 2014 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock reserved for issuance						14,548,013
Shares available for future grant						18,000,000
Percentage of exercise price fair value option grant in period						100.00%
Number of shares returned for each common stock						2.4
Stock Incentive Plans 2001 and After [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of exercise price fair value option grant in period						100.00%
Stock options granted to employees under plans prior to 2001, vested per quarter thereafter						6.25%
Stock options expired						10 years
Stock Incentive Plans 2001 and After [Member] | Share-based Compensation Award, Tranche One [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock options granted to employees under plans prior to 2001, vested after one year						25.00%
1997 Director Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share based compensation arrangement by share based payment award vesting period description						Options granted to directors generally vested at the earliest of (1) one day prior to the next annual meeting, (2) 13 months from the date of grant, or (3) the effective date of an acquisition.
Number of stock options outstanding						0	0
1997 Director Plan [Member] | Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period						1 day
1997 Director Plan [Member] | Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period						13 months
2014 ESPP Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares authorized for issuance						2,500,000
Percentage of payroll deduction to compensation						Up to 10%
Percentage of Common Stock through payroll deductions						10.00%
Amount of payroll deduction	$ 22,500,000					$ 21,250,000
Amount of payroll deduction increased						$ 22,500,000
Percentage of closing price of the Common Stock		90.00%				85.00%
Common stock, shares issued						105,506	139,079	140,531
Common stock reserved for issuance						2,032,403
2014 ESPP Plan [Member] | Offer Terminate [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of closing price of the Common Stock		90.00%				85.00%
2014 ESPP Plan [Member] | Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock, exercise price						$ 46.37	$ 31.40	$ 30.74
2014 ESPP Plan [Member] | Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock, exercise price						$ 74.12	$ 35.16	$ 31.34
Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares issued as per merger agreement						1,260,525
Number of RSUs outstanding						12,134	17,462
Dividend reinvestment						122	187
Restricted stock units, weighted average grant date fair value						$ 67.69
Total intrinsic value of options, stock appreciation rights exercised and fair value of RSUs vested						$ 60,302,000	$ 18,844,000	$ 12,868,000
Total compensation expense related to restricted stock unites and stock appreciation rights						$ 20,314,000
Estimated weighted average amortization period						11 months 4 days
Restricted Stock Units (RSUs) [Member] | Share-based Compensation Award, Tranche One [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock options granted to employees under plans prior to 2001, vested after one year						33.00%	33.00%	33.00%
Restricted Stock Units (RSUs) [Member] | Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period						1 day
Restricted Stock Units (RSUs) [Member] | Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period						13 months
Restricted Stock Units (RSUs) [Member] | Newport Deferred Compensation [Member] | Outside Directors [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Newport RSUs converted to MKS RSUs at Merger date						36,599
Newport RSUs converted to MKS RSUs at Merger date and released				5,515	19,137
RSUs Granted to Employees [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share based compensation arrangement by share based payment award vesting period description						Employees who are at least 60 years old and have a minimum of 10 Years of Service (as defined in the applicable RSU agreement) are expensed immediately.
Minimum years of service for RSU						10 years
RSUs Granted to Directors [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share based compensation arrangement by share based payment award vesting period description						Earliest of (1) one day prior to the next annual meeting, (2) 13 months from date of grant, or (3) the effective date of a change in control of the Company.
Stock Appreciation Rights (SARs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total intrinsic value of options, stock appreciation rights exercised and fair value of RSUs vested						$ 60,302,000	$ 18,844,000	$ 12,868,000
Total compensation expense related to restricted stock unites and stock appreciation rights						$ 20,314,000
Estimated weighted average amortization period						11 months 4 days
Employee Stock Option [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total intrinsic value of options, stock appreciation rights exercised and fair value of RSUs vested						$ 60,302,000	$ 18,844,000	$ 12,868,000
Newport [Member] | Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares issued as per merger agreement			360,674
Newport [Member] | Stock Appreciation Rights (SARs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares issued as per merger agreement			899,851

Stock-Based Compensation - Summ

Stock-Based Compensation - Summary of Activity for RSUs (Detail) - $ / shares	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted Average Grant Date Fair Value, Granted	$ 13.14	$ 8.52	$ 8.16
Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Non-vested RSUs/SARs - beginning of period	1,325,516
Granted	389,610
Vested	(684,967)
Forfeited or expired	(86,902)
Non-vested RSUs/SARs - end of period	943,379	1,325,516
RSUs/SARs, Weighted Average Grant Date Fair Value, Beginning of period	$ 34.38
Weighted Average Grant Date Fair Value, Granted	67.69
Weighted Average Grant Date Fair Value, Vested	34.58
Weighted Average Grant Date Fair Value, Forfeited or expired	38.97
RSUs/SARs, Weighted Average Grant Date Fair Value, end of period	$ 47.57	$ 34.38
Shares [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Accrued dividend shares	122
Weighted Average Grant Date Fair Value, Accrued dividend shares	$ 78.34

Stock-Based Compensation - Su94

Stock-Based Compensation - Summary of Activity for SARs (Detail) - Stock Appreciation Rights (SARs) [Member]	12 Months Ended
	Dec. 31, 2017$ / sharesshares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Non-vested RSUs/SARs - beginning of period | shares	599,334
Exercised, Outstanding SARs | shares	(289,822)
Forfeited or expired, Outstanding SARs | shares	(26,605)
Non-vested RSUs/SARs - end of period | shares	282,907
RSUs/SARs, Weighted Average Grant Date Fair Value, Beginning of period | $ / shares	$ 28.10
Exercised, Weighted Average Grant Date Fair Value | $ / shares	27.60
Forfeited or expired, Weighted Average Grant Date Fair Value | $ / shares	28.07
RSUs/SARs, Weighted Average Grant Date Fair Value, end of period | $ / shares	$ 28.62

Stock-Based Compensation - Su95

Stock-Based Compensation - Summary of Activity for Outstanding and Exercisable SARs (Detail) - Stock Appreciation Rights (SARs) [Member] - USD ($)	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock appreciation rights outstanding	282,907	599,334
Stock appreciation rights exercisable	221,375
Weighted Average Base Value, Stock appreciation rights outstanding	$ 28.62
Weighted Average Base Value, Stock appreciation rights exercisable	$ 27.92
Weighted Average Remaining Contractual Life, Stock appreciation rights outstanding	3 years 3 months 19 days
Weighted Average Remaining Contractual Life, Stock appreciation rights exercisable	3 years
Aggregate Intrinsic Value, Stock appreciation rights outstanding	$ 18,639
Aggregate Intrinsic Value, Stock appreciation rights exercisable	$ 14,740

Stock-Based Compensation - Effe

Stock-Based Compensation - Effect of Recording Stock-Based Compensation (Detail) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-based compensation	$ 24,378	$ 25,228	$ 13,013
Windfall tax effect on stock-based compensation	(11,071)
Net effect on net income	$ 13,307	$ 25,228	$ 13,013
Basic	$ 250	$ 470	$ 240
Diluted	$ 240	$ 470	$ 240
Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-based compensation	$ 22,428	$ 23,302	$ 11,885
Stock Appreciation Rights (SARs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-based compensation	529	700
Employee Stock Purchase Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-based compensation	$ 1,421	$ 1,226	$ 1,128

Stock-Based Compensation - Sche

Stock-Based Compensation - Schedule of Total Stock-Based Compensation Expense Included in Company's Consolidated Statements of Income and Comprehensive Income (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Total pre-tax stock-based compensation expense	$ 24,378	$ 25,228	$ 13,013
Cost of Revenues [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Total pre-tax stock-based compensation expense	3,894	2,997	1,814
Research and Development Expense [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Total pre-tax stock-based compensation expense	2,816	2,529	1,590
Selling, General and Administrative Expenses [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Total pre-tax stock-based compensation expense	$ 17,668	$ 19,702	$ 9,609

Stock-Based Compensation - Fair

Stock-Based Compensation - Fair Value of Employees' Purchase Rights Estimated Using Black-Scholes Option-Pricing Model (Detail) - $ / shares	3 Months Ended								12 Months Ended
	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Expected life (years)									6 months	6 months	6 months
Risk-free interest rate									0.80%	0.50%	0.10%
Expected volatility									26.50%	25.40%	26.40%
Expected annual dividends per share	$ 0.180	$ 0.175	$ 0.175	$ 0.175	$ 0.170	$ 0.170	$ 0.170	$ 0.170	$ 0.71	$ 0.68	$ 0.68

Employee Benefit Plans - Additi

Employee Benefit Plans - Additional Information (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Defined Benefit Plan Disclosure [Line Items]
Employee contribution to Company's profit sharing plan percentage	1.00%
Employee contribution to Company's profit sharing plan percentage	50.00%
Minimum age limit for specified additional amount	50 years
Company's contributions	$ 5,651	$ 6,524	$ 2,667
Bonus expense	46,783	28,097	14,599
Supplemental retirement benefits cost	3,478	1,805	$ 1,704
Accumulated benefit obligation	15,929	12,450
Defined benefit plan assets	8,152
Defined benefit plan, vested benefit obligations	17,932	16,224
Defined benefit plan expected future benefit payments	$ 2,283
Expected long-term rate of return on assets	1.90%
Israel [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan assets	$ 15,048	13,910
Japan [Member]
Defined Benefit Plan Disclosure [Line Items]
Expected long-term rate of return on assets	1.50%
United Kingdom [Member]
Defined Benefit Plan Disclosure [Line Items]
Expected long-term rate of return on assets	2.60%
France [Member]
Defined Benefit Plan Disclosure [Line Items]
Expected long-term rate of return on assets	1.60%
Germany [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan assets	$ 6,255	$ 5,558
Germany [Member] | Minimum [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan assets guaranteed rate of return	2.25%
Germany [Member] | Maximum [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan assets guaranteed rate of return	4.25%

Employee Benefit Plans - Summar

Employee Benefit Plans - Summary of Net Periodic Benefit Costs (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016
Defined Benefit Plan, Net Periodic Benefit Cost (Credit) [Abstract]
Service cost	$ 708	$ 479
Interest cost on projected benefit obligations	458	377
Expected return on plan assets	(116)	(84)
Amortization of actuarial net loss	400	406
Net periodic benefit costs	$ 1,450	$ 1,178

Employee Benefit Plans - Sum101

Employee Benefit Plans - Summary of Changes in Projected Benefit Obligations and Plan Assets, and Ending Balances of Defined Benefit Plans (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016
Change in projected benefit obligations:
Service cost	$ 708	$ 479
Interest cost	458	377
Newport [Member]
Change in plan assets:
Net underfunded status	(17,584)	(15,778)
Newport [Member] | Change in Projected Benefit Obligation [Member]
Change in projected benefit obligations:
Projected benefit obligations, beginning of year	23,450	2,134
Liabilities assumed through acquisition		22,437
Service cost	708	479
Interest cost	458	377
Actuarial (gain) loss	(312)	1,085
Benefits paid	(1,271)	(897)
Currency translation adjustments	2,703	(2,165)
Projected benefit obligations, end of year	25,736	23,450
Change in plan assets:
Gain on plan assets	(312)	1,085
Benefits paid	(1,271)	(897)
Newport [Member] | Change in Plan Assets [Member]
Change in projected benefit obligations:
Actuarial (gain) loss	177	66
Benefits paid	(722)	(437)
Change in plan assets:
Fair value of plan assets, beginning of year	7,672	301
Assets acquired through acquisition		7,896
Company contributions	324	741
Gain on plan assets	177	66
Benefits paid	(722)	(437)
Currency translation adjustments	701	(895)
Fair value of plan assets, end of year	$ 8,152	$ 7,672

Employee Benefit Plans - Sum102

Employee Benefit Plans - Summary of Changes in Plan Assets and Benefit Obligations Recognized in Other Comprehensive Income (Loss) (Detail) - USD ($) $ in Thousands		12 Months Ended
		Dec. 31, 2017	Dec. 31, 2016
Amounts recognized in accumulated comprehensive income:
Accumulated net actuarial (gain) loss		$ (235)	$ 465
Income tax benefit		(88)	(199)
Accumulated other comprehensive (benefit) loss	[1]	$ (323)	$ 266
[1]	Tax benefit was $(88) and $(199) for the years ended December 31, 2017 and 2016, respectively, and $0 for 2015.

Employee Benefit Plans - Sum103

Employee Benefit Plans - Summary of Estimated Benefit Payments for Next 10 Years (Detail) $ in Thousands	Dec. 31, 2017USD ($)
Defined Benefit Plan, Expected Future Benefit Payment [Abstract]
2,018	$ 2,283
2,019	2,786
2,020	2,900
2,021	2,997
2,022	2,858
2023-2027	13,027
Estimated benefit payments for next 10 years, total	$ 26,851

Employee Benefit Plans - Schedu

Employee Benefit Plans - Schedule of Weighted Average Rates Used to Determine Net Periodic Benefit Costs (Detail)	12 Months Ended
	Dec. 31, 2017
Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Net Periodic Benefit Cost [Abstract]
Discount rate	1.80%
Rate of increase in salary levels	2.20%
Expected long-term rate of return on assets	1.90%

Employee Benefit Plans - Sch105

Employee Benefit Plans - Schedule of Defined Benefit Plan Assets (Detail) $ in Thousands	Dec. 31, 2017USD ($)
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan assets, amount	$ 8,152
Defined benefit plan assets, percentage	100.00%
Cash [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan assets, amount	$ 561
Defined benefit plan assets, percentage	7.00%
Debt Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan assets, amount	$ 5,242
Defined benefit plan assets, percentage	64.00%
Equity Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan assets, amount	$ 1,367
Defined benefit plan assets, percentage	17.00%
Other [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan assets, amount	$ 982
Defined benefit plan assets, percentage	12.00%

Net Income Per Share - Reconcil

Net Income Per Share - Reconciliation of Basic and Diluted Net Income Per Share (Detail) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Numerator:
Net income	$ 77,638	$ 75,994	$ 120,440	$ 65,060	$ 45,487	$ 32,549	$ 9,210	$ 17,563	$ 339,132	$ 104,809	$ 122,297
Denominator:
Shares used in net income per common share - basic									54,137,000	53,472,000	53,282,000
Effect of dilutive securities									937,000	579,000	278,000
Shares used in net income per common share - diluted									55,074,000	54,051,000	53,560,000
Net income per common share:
Basic	$ 1.43	$ 1.40	$ 2.22	$ 1.21	$ 0.85	$ 0.61	$ 0.17	$ 0.33	$ 6.26	$ 1.96	$ 2.30
Diluted	$ 1.41	$ 1.38	$ 2.19	$ 1.18	$ 0.83	$ 0.60	$ 0.17	$ 0.33	$ 6.16	$ 1.94	$ 2.28

Net Income Per Share - Addition

Net Income Per Share - Additional Information (Detail) - shares	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Restricted Stock Units (RSUs) [Member]
Earnings Per Share [Line Items]
Number of shares excluded from computation of diluted earnings per share	404	508	0

Business Segment, Geographic108

Business Segment, Geographic Area, Product and Significant Customer Information - Additional Information (Detail)	12 Months Ended
	Dec. 31, 2017CustomerSegmentProduct
Segment Reporting [Abstract]
Number of reportable segments | Segment	2
Number of product groups | Product	6
Number of customers with net revenues greater than 10% of total net revenues | Customer	2
Entity wide net revenue major customer percentage minimum	10.00%

Business Segment, Geographic109

Business Segment, Geographic Area, Product and Significant Customer Information - Net Revenues by Reportable Segment (Detail) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Segment Reporting Information [Line Items]
Total net revenues	$ 511,800	$ 486,267	$ 480,757	$ 437,153	$ 405,140	$ 380,660	$ 325,861	$ 183,681	$ 1,915,977	$ 1,295,342	$ 813,524
Vacuum & Analysis [Member]
Segment Reporting Information [Line Items]
Total net revenues									1,207,457	872,291	$ 813,524
Light & Motion [Member]
Segment Reporting Information [Line Items]
Total net revenues									$ 708,520	$ 423,051

Business Segment, Geographic110

Business Segment, Geographic Area, Product and Significant Customer Information - Reconciliation of Segment Gross Profit to Consolidated Net Income (Detail) - USD ($) $ in Thousands	1 Months Ended	3 Months Ended								12 Months Ended
	Apr. 30, 2017	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Segment Reporting Information [Line Items]
Gross profit		$ 238,326	$ 227,995	$ 219,583	$ 205,547	$ 183,408	$ 168,385	$ 135,913	$ 77,913	$ 891,451	$ 565,619	$ 362,872
Research and development										132,555	110,579	68,305
Selling, general and administrative										290,548	229,171	129,087
Acquisition and integration costs										5,332	27,279	30
Restructuring										3,920	642	2,074
Asset impairment										6,719	5,000
Amortization of intangible assets										45,743	35,681	6,764
Income from operations		120,016	110,155	92,883	83,580	62,514	53,008	19,186	22,559	406,634	157,267	156,612
Interest income										3,021	2,560	2,999
Interest expense										30,990	30,611	143
Gain on sale of business	$ 74,856									74,856
Other expense, net										5,896	1,239
Income before income taxes										447,625	127,977	159,468
Provision for income taxes										108,493	23,168	37,171
Net income		$ 77,638	$ 75,994	$ 120,440	$ 65,060	$ 45,487	$ 32,549	$ 9,210	$ 17,563	339,132	104,809	122,297
Vacuum & Analysis [Member]
Segment Reporting Information [Line Items]
Gross profit										551,078	388,220	$ 362,872
Light & Motion [Member]
Segment Reporting Information [Line Items]
Gross profit										$ 340,373	$ 177,399

Business Segment, Geographic111

Business Segment, Geographic Area, Product and Significant Customer Information - Schedule of Capital Expenditures, Depreciation and Amortization Expense of Intangible Assets by Reportable Segment (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Segment Reporting Information [Line Items]
Capital expenditures	$ 31,287	$ 19,123	$ 12,414
Depreciation and amortization	82,556	65,926	22,103
Vacuum & Analysis [Member]
Segment Reporting Information [Line Items]
Capital expenditures	17,111	11,732	12,414
Depreciation and amortization	20,297	20,820	$ 22,103
Light & Motion [Member]
Segment Reporting Information [Line Items]
Capital expenditures	14,176	7,391
Depreciation and amortization	$ 62,259	$ 45,106

Business Segment, Geographic112

Business Segment, Geographic Area, Product and Significant Customer Information - Segment Assets by Reportable Segment (Detail) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Segment Reporting Information [Line Items]
Accounts receivable	$ 300,308	$ 248,757
Inventory	339,081	275,869
Total assets	2,414,018	2,212,242
Operating Segments [Member]
Segment Reporting Information [Line Items]
Accounts receivable	300,308	248,757
Inventory	339,081	275,869
Total assets	639,389	524,626
Operating Segments [Member] | Vacuum & Analysis [Member]
Segment Reporting Information [Line Items]
Accounts receivable	201,318	148,516
Inventory	197,831	165,040
Total assets	399,149	313,556
Operating Segments [Member] | Light & Motion [Member]
Segment Reporting Information [Line Items]
Accounts receivable	119,934	121,516
Inventory	141,250	110,829
Total assets	261,184	232,345
Corporate, Eliminations & Other [Member]
Segment Reporting Information [Line Items]
Accounts receivable	(20,944)	(21,275)
Total assets	$ (20,944)	$ (21,275)

Business Segment, Geographic113

Business Segment, Geographic Area, Product and Significant Customer Information - Reconciliation of Segment Assets to Consolidated Total Assets (Detail) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Segment Reporting, Asset Reconciling Item [Line Items]
Consolidated total assets	$ 2,414,018	$ 2,212,242
Other current assets	53,543	50,770
Property, plant and equipment, net	171,782	174,559
Other assets	37,883	32,467
Operating Segments [Member]
Segment Reporting, Asset Reconciling Item [Line Items]
Consolidated total assets	639,389	524,626
Segment Reconciling Items [Member]
Segment Reporting, Asset Reconciling Item [Line Items]
Cash and cash equivalents, restricted cash and investments	553,976	433,231
Other current assets	53,543	50,770
Property, plant and equipment, net	171,782	174,559
Goodwill and intangible assets, net	957,445	996,589
Other assets	$ 37,883	$ 32,467

Business Segment, Geographic114

Business Segment, Geographic Area, Product and Significant Customer Information - Schedule of Net Revenues and Long-Lived Assets by Geographic Regions (Detail) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Revenues from External Customers and Long-Lived Assets [Line Items]
Net revenues	$ 511,800	$ 486,267	$ 480,757	$ 437,153	$ 405,140	$ 380,660	$ 325,861	$ 183,681	$ 1,915,977	$ 1,295,342	$ 813,524
Long-lived assets	203,154				200,670				203,154	200,670
United States [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Net revenues									955,284	675,601	458,313
Long-lived assets	124,689				122,547				124,689	122,547
South Korea [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Net revenues									212,763	112,432	106,909
Japan [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Net revenues									167,318	96,954	62,879
Europe [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Net revenues									209,912	156,365	79,927
Long-lived assets	28,820				28,717				28,820	28,717
Asia (Excluding Korea and Japan) [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Net revenues									370,700	253,990	$ 105,496
Long-lived assets	$ 49,645				$ 49,406				$ 49,645	$ 49,406

Business Segment, Geographic115

Business Segment, Geographic Area, Product and Significant Customer Information - Summary of Goodwill Associated with Reportable Segments (Detail) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Segment Reporting Information [Line Items]
Goodwill	$ 591,047	$ 588,585	$ 199,703
Vacuum & Analysis [Member]
Segment Reporting Information [Line Items]
Goodwill	197,617	199,453
Light & Motion [Member]
Segment Reporting Information [Line Items]
Goodwill	$ 393,430	$ 389,132

Business Segment, Geographic116

Business Segment, Geographic Area, Product and Significant Customer Information - Worldwide Net Revenue for Each Group of Products (Detail) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Revenue from External Customer [Line Items]
Net sales from product groups	$ 511,800	$ 486,267	$ 480,757	$ 437,153	$ 405,140	$ 380,660	$ 325,861	$ 183,681	$ 1,915,977	$ 1,295,342	$ 813,524
Analytical and Control Solutions Products [Member]
Revenue from External Customer [Line Items]
Net sales from product groups									131,376	115,758	102,658
Power Plasma and Reactive Gas Solutions Products [Member]
Revenue from External Customer [Line Items]
Net sales from product groups									564,343	367,665	350,469
Vacuum Solutions Products [Member]
Revenue from External Customer [Line Items]
Net sales from product groups									511,738	388,868	$ 360,397
Laser Products [Member]
Revenue from External Customer [Line Items]
Net sales from product groups									225,168	124,432
Optics Products [Member]
Revenue from External Customer [Line Items]
Net sales from product groups									203,775	124,218
Photonics Products [Member]
Revenue from External Customer [Line Items]
Net sales from product groups									$ 279,577	$ 174,401

Business Segment, Geographic117

Business Segment, Geographic Area, Product and Significant Customer Information - Customers with Net Revenues Greater than 10% of Total Net Revenues (Detail) - Customer Concentration Risk [Member] - Sales Revenue, Net [Member]	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Applied Materials, Inc [Member]
Revenue, Major Customer [Line Items]
Percentage of total net revenues	12.70%	13.60%	17.80%
LAM Research Corporation [Member]
Revenue, Major Customer [Line Items]
Percentage of total net revenues	11.70%	11.20%	13.40%

Restructurings - Additional Inf

Restructurings - Additional Information (Detail) $ in Thousands	12 Months Ended
	Dec. 31, 2017USD ($)FacilitiesPlant	Dec. 31, 2016USD ($)Facilities	Dec. 31, 2015USD ($)
Reorganizations [Abstract]
Restructuring charges | $	$ 3,920	$ 642	$ 2,074
Number of manufacturing plants | Plant	2
Number of facilities consolidated | Facilities	1	1

Restructurings - Schedule of Co

Restructurings - Schedule of Company's Restructuring Activity (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Restructuring and Related Activities [Abstract]
Balance at January 1	$ 540	$ 807
Restructuring liability from Newport Merger		562
Charged to expense	3,920	642	$ 2,074
Payments and adjustment	(1,216)	(1,471)
Balance at December 31	$ 3,244	$ 540	$ 807

Commitments and Contingencies -

Commitments and Contingencies - Additional Information (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Commitments and Contingencies Disclosure [Abstract]
Lease expiration date	2,026
Rental expenses under operating leases	$ 19,693	$ 16,253	$ 7,845
Purchase commitments covered by aggregate value	$ 278,797
Purchase commitments	Less than one year

Commitments and Contingencie121

Commitments and Contingencies - Minimum Lease Payments under Operating Leases (Detail) $ in Thousands	Dec. 31, 2017USD ($)
Commitments and Contingencies Disclosure [Abstract]
2,018	$ 18,489
2,019	15,563
2,020	12,828
2,021	9,177
2,022	7,385
Thereafter	3,956
Total minimum lease payments	$ 67,398

Supplemental Financial Data (De

Supplemental Financial Data (Detail) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Statement of Operations Data
Net revenues	$ 511,800	$ 486,267	$ 480,757	$ 437,153	$ 405,140	$ 380,660	$ 325,861	$ 183,681	$ 1,915,977	$ 1,295,342	$ 813,524
Gross profit	238,326	227,995	219,583	205,547	183,408	168,385	135,913	77,913	891,451	565,619	362,872
Income from operations	120,016	110,155	92,883	83,580	62,514	53,008	19,186	22,559	406,634	157,267	156,612
Net income	$ 77,638	$ 75,994	$ 120,440	$ 65,060	$ 45,487	$ 32,549	$ 9,210	$ 17,563	$ 339,132	$ 104,809	$ 122,297
Net income per share:
Basic	$ 1.43	$ 1.40	$ 2.22	$ 1.21	$ 0.85	$ 0.61	$ 0.17	$ 0.33	$ 6.26	$ 1.96	$ 2.30
Diluted	1.41	1.38	2.19	1.18	0.83	0.60	0.17	0.33	6.16	1.94	2.28
Cash dividends paid per common share	$ 0.180	$ 0.175	$ 0.175	$ 0.175	$ 0.170	$ 0.170	$ 0.170	$ 0.170	$ 0.71	$ 0.68	$ 0.68

Schedule II - Valuation and 123

Schedule II - Valuation and Qualifying Accounts (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Valuation Allowance for Doubtful Accounts [Member]
Valuation and Qualifying Accounts Disclosure [Line Items]
Balance at Beginning of Year	$ 3,909	$ 1,760	$ 2,250
Additions Acquisition Beginning Balance		1,292
Additions Charged to Costs and Expenses	825	1,109	(255)
Additions Charged to Other Accounts		(66)	21
Deductions & Write-offs	(599)	(186)	(256)
Balance at End of Year	4,135	3,909	1,760
Valuation Allowance for Sales Returns [Member]
Valuation and Qualifying Accounts Disclosure [Line Items]
Balance at Beginning of Year	1,138	601	730
Additions Acquisition Beginning Balance		423
Additions Charged to Costs and Expenses	(142)	2,262	2,500
Additions Charged to Other Accounts			(3)
Deductions & Write-offs	299	(2,148)	(2,626)
Balance at End of Year	1,295	1,138	601
Valuation Allowance on Deferred Tax Asset [Member]
Valuation and Qualifying Accounts Disclosure [Line Items]
Balance at Beginning of Year	12,527	6,127	26,763
Additions Acquisition Beginning Balance		3,769
Additions Charged to Costs and Expenses	1,603	2,719
Additions Charged to Other Accounts			113
Deductions & Write-offs	(501)	(88)	(20,749)
Balance at End of Year	$ 13,629	$ 12,527	$ 6,127