Rudolph 10-Q 2 Nov 18 2018 Q3 Quarterly report Financial data

Document and Entity Information

Document and Entity Information Document - shares	9 Months Ended
	Sep. 30, 2018	Oct. 15, 2018
Document And Entity Information [Abstract]
Entity Registrant Name	RUDOLPH TECHNOLOGIES INC
Trading Symbol	RTEC
Entity Central Index Key	1,094,392
Current Fiscal Year End Date	--12-31
Entity Filer Category	Large Accelerated Filer
Document Type	10-Q
Document Period End Date	Sep. 30, 2018
Document Fiscal Year Focus	2,018
Document Fiscal Period Focus	Q3
Amendment Flag	false
Entity Small Business	false
Entity Emerging Growth Company	false
Entity Common Stock, Shares Outstanding		31,900,604

CONDENSED CONSOLIDATED BALANCE

CONDENSED CONSOLIDATED BALANCE SHEETS - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017
Current Assets:
Cash and cash equivalents	$ 124,334	$ 67,770
Marketable securities	70,005	109,589
Accounts receivable, less allowance of $956 and $460	68,512	65,283
Inventories, net	91,391	67,521
Income taxes receivable	3,253	7,220
Prepaid expenses and other current assets	8,976	4,699
Total current assets	366,471	322,082
Property, plant and equipment, net	16,763	17,342
Goodwill	22,495	22,495
Identifiable intangible assets, net	7,786	8,632
Other assets	16,395	15,371
Total assets	429,910	385,922
Current liabilities:
Accounts payable and accrued liabilities	30,095	26,800
Deferred revenue	7,564	6,223
Other current liabilities	7,922	9,284
Total current liabilities	45,581	42,307
Other non-current liabilities	10,173	10,461
Total liabilities	55,754	52,768
Commitments and contingencies
Stockholders’ equity:
Common stock	32	32
Additional paid-in capital	390,547	386,196
Accumulated other comprehensive loss	(1,568)	(1,205)
Accumulated deficit	(14,855)	(51,869)
Total stockholders’ equity	374,156	333,154
Total liabilities and stockholders’ equity	$ 429,910	$ 385,922

CONDENSED CONSOLIDATED BALANC_2

CONDENSED CONSOLIDATED BALANCE SHEETS (Parenthetical) - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017
Statement Of Financial Position [Abstract]
Allowance for Doubtful Accounts Receivable, Current	$ 956	$ 460

CONDENSED CONSOLIDATED STATEMEN

CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS (Unaudited) - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Consolidated Statements Of Operations [Abstract]
Revenue	$ 60,432	$ 66,920	$ 211,004	$ 195,017
Cost of revenue	28,978	31,775	95,393	92,548
Gross profit	31,454	35,145	115,611	102,469
Operating expenses:
Research and development	12,313	12,020	36,829	36,176
Selling, general and administrative	11,128	10,102	35,867	29,880
Amortization	384	506	1,147	1,516
Patent litigation income	0	(13,000)	0	(13,000)
Total operating expenses	23,825	9,628	73,843	54,572
Operating income	7,629	25,517	41,768	47,897
Interest income, net	(607)	(244)	(1,474)	(658)
Other expense (income), net	(132)	98	(90)	533
Income before income taxes	8,368	25,663	43,332	48,022
Provision for income taxes	1,181	8,294	6,318	14,309
Net income	$ 7,187	$ 17,369	$ 37,014	$ 33,713
Earnings per share:
Basic	$ 0.23	$ 0.55	$ 1.16	$ 1.07
Diluted	$ 0.22	$ 0.54	$ 1.14	$ 1.05
Weighted average shares outstanding:
Basic	31,901	31,571	31,807	31,455
Diluted	32,408	32,170	32,387	32,126

CONDENSED CONSOLIDATED STATEM_2

CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (Unaudited) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Consolidated Statement Of Comprehensive Income [Abstract]
Net income	$ 7,187	$ 17,369	$ 37,014	$ 33,713
Other comprehensive income:
Change in net unrealized gains (losses) on marketable securities, net of tax	(68)	(2)	62	43
Change in currency translation adjustments	(202)	91	(425)	1,344
Total comprehensive income	$ 6,917	$ 17,458	$ 36,651	$ 35,100

CONDENSED CONSOLIDATED STATEM_3

CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS (Unaudited) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017
Cash flows from operating activities:
Net income	$ 37,014	$ 33,713
Adjustments to reconcile net income to net cash and cash equivalents provided by operating activities:
Amortization of intangibles	1,147	1,516
Depreciation	3,634	2,925
Foreign currency exchange loss	217	533
Change in fair value of contingent consideration	603	132
Share-based compensation	4,879	4,413
Provision for doubtful accounts and inventory valuation	3,105	3,019
Patent litigation income		(13,000)
Changes in operating assets and liabilities	(26,160)	9,536
Net cash and cash equivalents provided by operating activities	24,439	42,787
Cash flows from investing activities:
Purchases of marketable securities	(113,353)	(103,224)
Proceeds from sales of marketable securities	152,588	99,931
Cash advanced on convertible note receivable	(1,000)
Purchases of property, plant and equipment	(4,127)	(7,447)
Net cash and cash equivalents provided by (used in) investing activities	34,108	(10,740)
Cash flows from financing activities:
Redemption of stock warrants	0	(1,025)
Purchase of common stock	(38)
Tax payments related to shares withheld for share-based compensation plans	(980)	(1,331)
Payment of contingent consideration for acquired business	(1,057)	(358)
Issuance of shares through share-based compensation plans	490	289
Net cash and cash equivalents used in financing activities	(1,585)	(2,425)
Effect of exchange rate changes on cash and cash equivalents	(398)	545
Net increase in cash and cash equivalents	56,564	30,167
Cash and cash equivalents at beginning of period	67,770	37,859
Cash and cash equivalents at end of period	124,334	68,026
Supplemental disclosure of cash flow information:
Income taxes paid	$ 2,389	$ 6,917

Basis of Presentation

Basis of Presentation	9 Months Ended
	Sep. 30, 2018
Organization And Nature Of Operations [Abstract]
Basis of Presentation	NOTE 1. Basis of Presentation The accompanying interim unaudited Condensed Consolidated Financial Statements have been prepared by Rudolph Technologies, Inc. (the “Company” or “Rudolph”) and in the opinion of management reflect all adjustments, consisting of normal recurring accruals, necessary for their fair presentation in accordance with accounting principles generally accepted in the United States of America (“U.S. GAAP”). Preparing financial statements requires management to make estimates and assumptions that affect amounts reported in the financial statements and accompanying notes. Actual amounts could differ materially from reported amounts. The interim results for the three and nine month periods ended September 30, 2018 are not necessarily indicative of results to be expected for the entire year or any future periods. This interim financial information should be read in conjunction with the financial statements and the notes thereto included in the Company’s Annual Report on Form 10-K for the year ended December 31, 2017 (“2017 10-K”) filed with the Securities and Exchange Commission (“SEC”) on February 16, 2018. The accompanying Condensed Consolidated Balance Sheet at December 31, 2017 has been derived from the audited consolidated financial statements included in the 2017 10-K. Recent Accounting Pronouncements Recently Adopted Effective January 1, 2018, the Company adopted Accounting Standards Update (“ASU”) No. 2016-16, “Income Tax (Topic 740): Intra-Entity Transfers of Assets Other Than Inventory.” This ASU, which is part of the simplification initiative of the Financial Accounting Standards Board (“FASB”), is intended to reduce the complexity of U.S. GAAP and diversity in practice related to the tax consequences of certain types of intra-entity asset transfers, particularly those involving intellectual property. The adoption of ASU No. 2016-16 did not have any impact on the Company’s consolidated financial position, results of operations, and cash flows. Effective January 1, 2018, the Company adopted ASU No. 2016-15, “Statement of Cash Flows (Topic 230): Classification of Certain Cash Receipts and Cash Payments.” This ASU provides guidance on statement of cash flows presentation for eight specific cash flow issues where diversity in practice exists. The adoption of ASU No. 2016-15 did not have a material impact on the Company’s consolidated financial position, results of operations, and cash flows. Effective January 1, 2018, the Company adopted ASU No. 2014-09, “Revenue from Contracts with Customers (Topic 606),” which supersedes nearly all existing revenue recognition guidance. The core principle of this ASU is that revenue should be recognized to depict the transfer of promised goods or services to customers in an amount that reflects the consideration to which the entity expects to be entitled in exchange for those goods or services. Recently Issued In August 2018, the FASB issued ASU No. 2018-13, “Fair Value Measurement (Topic 820): Disclosure Framework – Changes to the Disclosure Requirements for Fair Value Measurement.” This ASU is part of the FASB’s larger disclosure framework project intended to improve the effectiveness of financial statement footnote disclosure. ASU 2018-13 modifies required fair value disclosures related primarily to level 3 investments. This ASU is effective for annual periods beginning after December 15, 2019 and interim periods within those annual periods. The adoption of ASU 2018-13 is not expected to have a material effect on the Company’s consolidated financial position, results of operations, and cash flows. In June 2018, the FASB issued ASU No. 2018-07, “Compensation – Stock Compensation (Topic 718): Improvements to Nonemployee Share-Based Payment Accounting.” This ASU expands the scope of Topic 718 to include share-based payment transactions for acquiring goods and services from nonemployees. An entity should apply the requirements of Topic 718 to nonemployee awards except for specific guidance on inputs to an option pricing model and the attribution of cost. The ASU is effective for the fiscal years beginning after December 15, 2018, including interim periods within that fiscal year. The adoption of ASU 2018-07 is not expected to have a material effect on the Company’s consolidated financial position, results of operations, and cash flows. In February 2018, the FASB issued ASU 2018-02, “Income Statement – Reporting Comprehensive Income (Topic 220): Reclassification of Certain Tax Effects from Accumulated Other Comprehensive Income.” The new guidance allows companies to reclassify stranded tax effects resulting from the Tax Cuts and Jobs Act (the “2017 Tax Act”) from accumulated other comprehensive income to retained earnings. The guidance also requires certain new disclosures regardless of a company’s election. The standard is effective for annual periods beginning after December 15, 2018 and for interim periods within those annual periods, with earlier adoption permitted. The adoption of ASU 2018-02 is not expected to have a material effect on the Company’s consolidated financial position, results of operations, and cash flows. In May 2017, the FASB issued ASU No. 2017-09, “Compensation - Stock Compensation (Topic718): Scope of Modification Accounting.” This ASU amends the scope of modification accounting for share-based payment arrangements and provides guidance on the types of changes to the terms or conditions of share-based payment awards to which an entity would be required to apply modification accounting under Accounting Standards Codification (“ASC”) 718. The ASU is effective for the fiscal years beginning after December 15, 2019 and for interim periods within those fiscal years. The Company is currently evaluating the effect the adoption of ASU No. 2017-09 will have on its consolidated financial position, results of operations, and cash flows, if any. In January 2017, the FASB issued ASU No. 2017-04, “Intangibles – Goodwill and Other (Topic 350): Simplifying the Test for Goodwill Impairment.” This ASU eliminates Step 2 from the goodwill impairment test. Accordingly, if the carrying amount of a reporting unit exceeds its fair value, an impairment loss will be recognized in an amount equal to the excess, limited to the total amount of goodwill allocated to the reporting unit. The ASU is effective for the fiscal years beginning after December 15, 2019 and for interim periods within those fiscal years. The Company is currently evaluating the effect the adoption of ASU No. 2017-04 will have on its consolidated financial position, results of operations, and cash flows, if any. In June 2016, the FASB issued ASU No. 2016-13, “Financial Instruments – Credit Losses (Topic 326),” which introduces new guidance for the accounting for credit losses on instruments within its scope. Given the breadth of that scope, the new ASU will impact both financial services and non-financial services entities. The standard is effective for fiscal years beginning after December 15, 2020. The Company is currently evaluating the effect the adoption of ASU No. 2016-13 will have on its consolidated financial position, results of operations, and cash flows, if any. In February 2016, the FASB issued ASU No. 2016-02, “Leases (Topic 842).” The FASB issued this update to require the recognition of lease assets and lease liabilities on the balance sheet of lessees. In July 2018, the FASB issued ASU No. 2018-11, “Leases (Topic 842): Targeted Improvements” and ASU No. 2018-10, “Codification Improvements to Topic 842, Leases.” ASU No. 2016-02 and the subsequent modifications are identified as “ASC 842.” ASC 842 will be effective for fiscal years beginning after December 15, 2018, including interim periods within such fiscal years. Early adoption is permitted. The Company intends to adopt ASC 842 using a modified retrospective transition method and will elect the package of practical expedients. The Company expects adoption to increase the assets and liabilities recorded on its consolidated balance sheet and increase the level of disclosures related to leases. In addition, the Company is in the process of identifying appropriate changes to its accounting policies, business processes, and related internal controls to support recognition and disclosure requirements under ASC 842. Recently issued accounting guidance not discussed above is not applicable or did not have, or is not expected to have, a material impact to the Company.

Revenue

Revenue	9 Months Ended
	Sep. 30, 2018
Revenue From Contract With Customer [Abstract]
Revenue	NOTE 2. Revenue Adoption of ASC Topic 606, “Revenue from Contracts with Customers” On January 1, 2018, the Company adopted Topic 606 using the modified retrospective method applied to those contracts which were not completed as of January 1, 2018. Results for reporting periods beginning after January 1, 2018 are presented under Topic 606, while comparative information has not been restated and continues to be reported under the accounting standards in effect for those periods. The Company did not record a cumulative impact due to the adoption of Topic 606. Revenue Recognition Revenue is recognized when control of the promised goods or services are transferred to the Company’s customers in an amount that reflects the consideration the Company expects to be entitled to receive in exchange for those goods or services. The Company accounts for a contract when it has approval and commitment from both parties, the rights of the parties and payment terms are identified, the contract has commercial substance and collectability of consideration is probable. The Company has elected to account for shipping and handling activities as the fulfillment of a promise to transfer goods to the customer and therefore records these activities under the caption “Cost of revenue.” Sales tax and any other taxes collected concurrent with revenue producing activities are excluded from revenue. Incidental items that are immaterial in the context of the contract are recognized as expense. These accounting policy elections are consistent with the manner in which the Company has historically recorded these items. Contracts with customers may include multiple performance obligations. For such arrangements, the Company allocates revenue to each performance obligation based on its relative standalone selling price. The Company generally determines standalone selling prices based on the prices charged to customers or the expected cost plus margin. Disaggregated Revenue The following table presents the Company’s revenue disaggregated by revenue source: Three Months Ended Nine Months Ended September 30, September 30, 2018 2017 2018 2017 Systems $ 43,955 $ 50,831 $ 160,170 $ 145,968 Software licensing, support and maintenance 6,877 6,053 21,879 20,447 Parts 7,141 7,101 20,884 20,779 Services 2,459 2,935 8,071 7,823 Total revenue $ 60,432 $ 66,920 $ 211,004 $ 195,017 The following table represents a disaggregation of revenue by timing of revenue: Three Months Ended Nine Months Ended September 30, September 30, 2018 2018 Point-in-time $ 56,185 $ 198,864 Over-time 4,247 12,140 Total revenue $ 60,432 $ 211,004 See Note 15 for additional discussion of the Company’s disaggregated revenue in detail. Systems Revenue Revenue from systems is recognized when the Company transfers control of the product to the customer. To indicate transfer of control, the Company must have a present right to payment, legal title must have passed to the customer and the customer must have the significant risks and rewards of ownership. The Company generally transfers control for system sales when the customer or the customer’s agent picks up the system at the Company’s facility. Payment for the majority of the Company’s systems have 80-90% of the invoice amount due within 30 days and the remaining amount due upon customer acceptance, which includes installation, recalibration and qualification by the customer. Customer acceptance is generally based on the Company’s products meeting published performance specifications, which have been demonstrated prior to shipment. The Company provides an assurance warranty on its systems for a period of twelve to fifteen months against defects in material and workmanship. The Company provides for the estimated cost of product warranties at the time revenue is recognized. Depending on the terms of the systems arrangement, the Company may also defer the recognition of a portion of the consideration expected to be received because the Company has to satisfy a future obligation ( e.g., Software Licensing, Support and Maintenance Revenue Revenue from software licenses provides the customer with a right to use the software as it exists when made available to the customer. Revenue from software licenses are recognized upfront at the point in time when the software is made available to the customer. Revenue from licensing support and maintenance is recognized as the support and maintenance are provided, which is over the contract period. Payment for software licensing, support and maintenance is generally due in 30 days. Parts Revenue Revenue from parts is recognized when the Company transfers control of the product, which typically occurs when the Company ships the product from its facilities to the customer. Payment for parts is generally due in 30 days. Services Revenue Revenue from services primarily consists of service contracts, which provide additional maintenance coverage beyond the Company’s assurance warranty on its products, service labor, consulting and training. Revenue from service contracts is recognized ratably over the term of the service contract. Revenue from service labor, consulting and training is recognized as services are performed. Payment for services is generally due in 30 days. Contract Liabilities The Company records contract liabilities when the customer has been billed in advance of the Company completing its performance obligations. These amounts are recorded as deferred revenue in the Consolidated Balance Sheets. The beginning balance in deferred revenue was $7,206 as of January 1, 2018. Changes in deferred revenue were as follows: Three Months Ended Nine Months Ended September 30, September 30, 2018 2018 Balance, beginning of the period $ 8,799 $ 7,206 Deferral of revenue 4,354 15,002 Recognition of deferred revenue (4,449 ) (13,504 ) Balance, ending of the period $ 8,704 $ 8,704 Practical Expedients The Company generally expenses sales commissions when incurred because the amortization period is one year or less. These costs are recorded within selling, general and administrative expenses. The Company does not adjust the amount of consideration for the effects of a significant financing component as the payment terms are generally one year or less. The Company does not disclose the value of remaining performance obligations for contracts with an original expected length of one year or less and contracts for which the Company recognizes revenue in the amount to which it has the right to invoice.

Fair Value Measurements

Fair Value Measurements	9 Months Ended
	Sep. 30, 2018
Fair Value Measurements [Abstract]
Fair Value Measurements	NOTE 3. Fair Value Measurements The Company applies a three-level valuation hierarchy for fair value measurements. This hierarchy prioritizes the inputs into three broad levels. Level 1 inputs are quoted prices (unadjusted) in active markets for identical assets or liabilities. Level 2 inputs are quoted prices for similar assets and liabilities in active markets or inputs that are observable for the asset or liability, either directly or indirectly through market corroboration, for substantially the full term of the asset or liability. Level 3 inputs are unobservable inputs based on management’s assumptions used to measure assets and liabilities at fair value. A financial asset’s or liability’s fair value measurement classification within the hierarchy is determined based on the lowest level input that is significant to the fair value measurement. The following tables provide the assets and liabilities carried at fair value measured on a recurring basis at September 30, 2018 and December 31, 2017: Fair Value Measurements Using Carrying Value Quoted Prices in Active Markets for Identical Assets (Level 1) Significant Other Observable Inputs (Level 2) Significant Unobservable Inputs (Level 3) September 30, 2018 Assets: Available-for-sale debt securities: Municipal notes and bonds $ 70,005 $ — $ 70,005 $ — Foreign currency forward exchange contracts 156 — 156 — Total assets $ 70,161 $ — $ 70,161 $ — Liabilities: Contingent consideration - acquisitions 2,139 — — 2,139 Total liabilities $ 2,139 $ — $ — $ 2,139 December 31, 2017 Assets: Available-for-sale debt securities: Municipal notes and bonds $ 109,589 $ — $ 109,589 $ — Foreign currency forward exchange contracts 45 — 45 — Total assets $ 109,634 $ — $ 109,634 $ — Liabilities: Contingent consideration - acquisitions $ 2,593 $ — $ — $ 2,593 Total liabilities $ 2,593 $ — $ — $ 2,593 The Company’s available-for-sale debt securities classified as Level 1 are based on quoted market prices that are available in active markets. The Company’s available-for-sale debt securities classified as Level 2 are valued using observable inputs to quoted market prices, benchmark yields, reported trades, broker/dealer quotes or alternative pricing sources with reasonable levels of price transparency. The foreign currency forward exchange contracts are primarily measured based on the foreign currency spot and forward rates quoted by the banks or foreign currency dealers. Investment prices are obtained from third party pricing providers, which model prices utilizing the above observable inputs, for each asset class. Level 3 liabilities consisted of contingent consideration related to an acquisition for which the Company uses a discounted cash flow model to value these liabilities. The Level 3 assumptions used in the discounted cash flow model for the contingent consideration included projected revenue, timing of cash flows and estimates of discount rates of 9.4% and 8.6% for the nine months ended September 30, 2018 and 2017, respectively. A significant decrease in the projected revenue or increase in discount rates could result in a significantly lower fair value measurement for the contingent consideration. This table presents a reconciliation of all liabilities measured at fair value on a recurring basis using significant unobservable inputs (Level 3) for the nine months ended September 30, 2018: Fair Value Measurements Using Significant Unobservable Inputs (Level 3) Balance at December 31, 2017 $ 2,593 Additions — Total loss included in selling, general and administrative expense 603 Payments (1,057 ) Transfers into (out of) Level 3 — Balance at September 30, 2018 $ 2,139 See Note 4 for additional discussion regarding the fair value of the Company’s marketable securities. Fair Value of Other Financial Instruments The carrying value of cash and cash equivalents, accounts receivable, accounts payable and accrued liabilities approximates fair value because of the short-term maturity of these instruments. The estimated fair value of these obligations is based primarily on a market approach, comparing the Company’s interest rates to those rates the Company believes it would reasonably receive upon re-entry into the market. Judgment is required to estimate the fair value, using available market information and appropriate valuation methods. The carrying amount of the convertible note receivable approximates fair value based on current interest rates for instruments with similar characteristics.

Marketable Securities

Marketable Securities	9 Months Ended
	Sep. 30, 2018
Marketable Securities [Abstract]
Marketable Securities	NOTE 4. Marketable Securities The Company has evaluated its investment policies and has determined that all of its marketable securities, which are comprised of debt securities, are to be classified as available-for-sale. The Company’s available-for-sale debt securities are carried at fair value, with the unrealized gains and losses reported in Stockholders’ equity under the caption “Accumulated other comprehensive loss.” Realized gains and losses on available-for-sale debt securities are included in “Other expense” in the Condensed Consolidated Statements of Operations. The Company records other-than-temporary impairment charges for its available-for-sale debt securities when it intends to sell the securities, it is more-likely-than not that it will be required to sell the securities before a recovery, or when it does not expect to recover the entire amortized cost basis of the securities. The cost of securities sold is based on the specific identification method. The Company has determined that the gross unrealized losses on its marketable securities at September 30, 2018 and December 31, 2017 are temporary in nature. The Company reviews its investment portfolio to identify and evaluate marketable securities that have indications of possible impairment. Factors considered in determining whether a loss is other-than-temporary include the length of time and extent to which fair value has been less than the cost basis, credit quality and the Company’s ability and intent to hold the securities for a period of time sufficient to allow for any anticipated recovery in market value. At September 30, 2018 and December 31, 2017, marketable securities are categorized as follows: Amortized Cost Gross Unrealized Holding Gains Gross Unrealized Holding Losses Fair Value September 30, 2018 Municipal notes and bonds $ 70,092 $ — $ 87 $ 70,005 Total marketable securities $ 70,092 $ — $ 87 $ 70,005 December 31, 2017 Municipal notes and bonds $ 109,750 $ — $ 161 $ 109,589 Total marketable securities $ 109,750 $ — $ 161 $ 109,589 The amortized cost and estimated fair value of marketable securities classified by the maturity date listed on the security, regardless of the Condensed Consolidated Balance Sheet classification, are as follows at September 30, 2018 and December 31, 2017: September 30, 2018 December 31, 2017 Amortized Cost Fair Value Amortized Cost Fair Value Due within one year $ 63,901 $ 63,831 $ 104,742 $ 104,605 Due after one through five years 6,191 6,174 5,008 4,984 Due after five through ten years — — — — Due after ten years — — — — Total marketable securities $ 70,092 $ 70,005 $ 109,750 $ 109,589 The following table summarizes the estimated fair value and gross unrealized holding losses of marketable securities, aggregated by investment instrument and period of time in an unrealized loss position, at September 30, 2018 and December 31, 2017: Unrealized Loss Position For Less Than 12 Months Unrealized Loss Position For Greater Than 12 Months Fair Value Gross Unrealized Losses Fair Value Gross Unrealized Losses September 30, 2018 Municipal notes and bonds $ 50,097 $ 70 $ 7,172 $ 17 Total $ 50,097 $ 70 $ 7,172 $ 17 December 31, 2017 Municipal notes and bonds $ 98,805 $ 161 $ — $ — Total $ 98,805 $ 161 $ — $ — See Note 2 for additional discussion regarding the fair value of the Company’s marketable securities.

Convertible Note Receivable

Convertible Note Receivable	9 Months Ended
	Sep. 30, 2018
Receivables [Abstract]
Convertible Note Receivable	NOTE 5. Convertible Note Receivable The Company entered into a convertible loan agreement with Simax Precision Technologies Limited (“Simax”) on May 31, 2018. Simax may borrow from the Company up to $15,000 in multiple promissory notes. The Company expects to be a supplier of lithography modules to Simax which is focused on the manufacture, sale and service of lithography systems. The convertible notes will bear a rate of interest of 4.25% per annum payable on a semi-annual basis. The convertible notes provide the Company with the option to convert the outstanding indebtedness into equity. If the Company does not elect to exercise its option to convert the notes, Simax will repay the principal amount outstanding and any outstanding interest in equal installments beginning on the fifth anniversary of the loan date and continuing on a quarterly basis over the next three years. As of September 30, 2018, the Convertible notes receivable balance was $1,000 with accrued interest of $4.

Derivative Instruments and Hedg

Derivative Instruments and Hedging Activities	9 Months Ended
	Sep. 30, 2018
Derivative Instruments And Hedging Activities Disclosure [Abstract]
Derivative Instruments and Hedging Activities	NOTE 6. Derivative Instruments and Hedging Activities The Company, when it considers it to be appropriate, enters into forward exchange contracts to hedge the economic exposures arising from foreign currency denominated transactions. At September 30, 2018 and December 31, 2017, these contracts included the future sale of Japanese Yen to purchase U.S. dollars. Derivative instruments are recognized as either, “Prepaid expenses and other current assets” or “Other current liabilities” in the Condensed Consolidated Balance Sheets and are measured at fair value. The foreign currency forward exchange contracts were entered into by the Company’s Japanese subsidiary to economically hedge a portion of certain intercompany obligations. The forward exchange contracts are not designated as hedges for accounting purposes and increases in the fair value of $111 for the nine months ended September 30, 2018 and a decrease in the fair value of $251 for the nine months ended September 30, 2017, are recorded under the caption “Other expense (income), net” in the Condensed Consolidated Statements of Operations. The dollar equivalent of the U.S. dollar forward exchange contracts and related fair values as of September 30, 2018 and December 31, 2017 were as follows: September 30, 2018 December 31, 2017 Notional amount $ 5,709 $ 8,417 Fair value of asset $ 156 $ 45

Purchased Intangible Assets

Purchased Intangible Assets	9 Months Ended
	Sep. 30, 2018
Purchased Intangible Assets [Abstract]
Purchased Intangible Assets	NOTE 7. Purchased Intangible Assets Purchased intangible assets as of September 30, 2018 and December 31, 2017 are as follows: Gross Carrying Amount Accumulated Amortization Net September 30, 2018 Finite-lived intangibles: Developed technology $ 66,127 $ 59,396 $ 6,731 Customer and distributor relationships 9,561 9,016 545 Trade names 4,361 3,851 510 Total identifiable intangible assets $ 80,049 $ 72,263 $ 7,786 December 31, 2017 Finite-lived intangibles: Developed technology $ 65,827 $ 58,522 $ 7,305 Customer and distributor relationships 9,560 8,818 742 Trade names 4,361 3,776 585 Total identifiable intangible assets $ 79,748 $ 71,116 $ 8,632 Intangible asset amortization expenses for the three and nine months ended September 30, 2018 were $384 and $1,147, respectively. For the three and nine month periods ended September 30, 2017, intangible assets amortization expenses were $506 and $1,516, respectively. Assuming no change in the gross carrying value of identifiable intangible assets and estimated lives, estimated amortization expenses for the remainder of 2018 are $386, and for each of the next five years estimated amortization expenses are $1,544 for 2019, $1,341 for 2020, $594 for 2021, $527 for 2022, and $511 for 2023.

Balance Sheet Details

Balance Sheet Details	9 Months Ended
	Sep. 30, 2018
Balance Sheet Detail [Abstract]
Balance Sheet Details	NOTE 8. Balance Sheet Details Inventories Inventories are comprised of the following: September 30, 2018 December 31, 2017 Materials $ 55,856 $ 39,765 Work-in-process 24,467 20,923 Finished goods 11,068 6,833 Total inventories $ 91,391 $ 67,521 The Company has established reserves of $12,164 and $13,035 as of September 30, 2018 and December 31, 2017, respectively, for slow moving and obsolete inventory, which are included in the amounts above. Property, Plant and Equipment Property, plant and equipment, net is comprised of the following: September 30, 2018 December 31, 2017 Land and building $ 2,584 $ 2,584 Machinery and equipment 29,370 29,870 Furniture and fixtures 3,267 3,201 Computer equipment and software 6,749 5,444 Leasehold improvements 9,494 9,472 51,464 50,571 Accumulated depreciation (34,701 ) (33,229 ) Total property, plant and equipment, net $ 16,763 $ 17,342 Other assets Other assets is comprised of the following: September 30, 2018 December 31, 2017 Deferred income taxes $ 14,896 $ 14,879 Convertible note receivable $ 1,000 $ — Other 499 492 Total other assets $ 16,395 $ 15,371 Other current liabilities Other current liabilities is comprised of the following: September 30, 2018 December 31, 2017 Intangible asset acquisition - Stella Alliance $ 250 $ 100 Contingent consideration - acquisitions 781 634 Customer deposits 877 5,561 Other 6,014 2,989 Total other current liabilities $ 7,922 $ 9,284 Other non-current liabilities Other non-current liabilities is comprised of the following: September 30, 2018 December 31, 2017 Unrecognized tax benefits (including interest) $ 4,698 $ 4,660 Contingent consideration - acquisitions 1,358 1,959 Deferred revenue 1,140 983 Other 2,977 2,859 Total other non-current liabilities $ 10,173 $ 10,461

Commitments and Contingencies

Commitments and Contingencies	9 Months Ended
	Sep. 30, 2018
Commitments And Contingencies [Abstract]
Commitments and Contingencies	NOTE 9. Commitments and Contingencies Intellectual Property Indemnification Obligations The Company has entered into agreements with customers that include limited intellectual property indemnification obligations that are customary in the industry. These guarantees generally require the Company to compensate the other party for certain damages and costs incurred as a result of third party intellectual property claims arising from these transactions. The nature of the intellectual property indemnification obligations prevents the Company from making a reasonable estimate of the maximum potential amount it could be required to pay to its customers. Historically, the Company has not made any indemnification payments under such agreements and no amount has been accrued in the accompanying Condensed Consolidated Financial Statements with respect to these indemnification guarantees. Warranty Reserves The Company generally provides a warranty on its products for a period of 12 to 15 months against defects in material and workmanship. The Company estimates the costs that may be incurred during the warranty period and records a liability in the amount of such costs at the time revenue is recognized. The Company’s estimate is based primarily on historical experience. The Company periodically assesses the adequacy of its recorded warranty liabilities and adjusts the amounts as necessary. Settlements of warranty reserves are generally associated with sales that occurred during the 12 to 15 months prior to the quarter-end and warranty accruals are related to sales during the same year. Changes in the Company’s warranty reserves are as follows: Nine Months Ended September 30, 2018 2017 Balance, beginning of the period $ 2,427 $ 1,788 Accruals 2,720 2,511 Usage (2,589 ) (2,025 ) Balance, end of the period $ 2,558 $ 2,274 Warranty reserves are reported in the Condensed Consolidated Balance Sheets under the caption “Accounts payable and accrued liabilities.” Legal Matters From time to time, the Company is subject to legal proceedings and claims in the ordinary course of business. There are no legal proceedings pending or threatened against the Company that management believes are likely to have a material adverse effect on the Company’s consolidated financial position or otherwise. Line of Credit The Company has a credit agreement with a bank that provides for a line of credit which is secured by the marketable securities the Company has with the bank. The Company is permitted to borrow up to 70% of the value of eligible securities held at the time the line of credit is accessed. The available line of credit as of September 30, 2018 was approximately $102 million with an available interest rate of 3.8%. The credit agreement is available to the Company until such time that either party terminates the arrangement at their discretion. The Company has not utilized the line of credit to date.

Share-Based Compensation

Share-Based Compensation	9 Months Ended
	Sep. 30, 2018
Share Based Compensation [Abstract]
Share-Based Compensation	NOTE 10. Share-Based Compensation Restricted Stock Unit Activity A summary of the activity with respect to the Company’s unvested restricted stock units during the nine months ended September 30, 2018 is as follows: Number of Shares Weighted Average Grant Date Fair Value Nonvested at December 31, 2017 1,014 $ 14.88 Granted 274 $ 28.25 Vested (300 ) $ 14.22 Forfeited (68 ) $ 17.50 Nonvested at September 30, 2018 920 $ 18.89 Included in the number of shares granted in the table directly above are 53 market performance-based restricted stock units (“MPRSUs”) granted to executives in 2018. Vesting of these MPRSUs is contingent upon the Company meeting certain total shareholder return (“TSR”) levels as compared to a select peer group over three years from the year granted. The 2018 MPRSUs cliff vest at the end of the three-year period and have a maximum potential to vest at 200% (105 shares) based on TSR performance. The related share-based compensation expense is determined based on the estimated fair value of the underlying shares on the date of grant and is recognized straight-line over the vesting term. The estimated fair value per share of the MPRSUs was $30.76. As of September 30, 2018 and December 31, 2017, there was $11,088 and $9,420 of total unrecognized compensation cost related to restricted stock units granted under the Company’s stock plans, respectively. That cost is expected to be recognized over a weighted average period of 2.1 years and 2.2 years for each of the respective periods.

Other Expense (Income), net

Other Expense (Income), net	9 Months Ended
	Sep. 30, 2018
Other Income Expense [Abstract]
Other Expense (Income), net	NOTE 11. Other Expense (Income), net Other expense (income), net is comprised of the following: Three Months Ended September 30, Nine Months Ended September 2018 2017 2018 2017 Gain on casualty insurance claim $ (302 ) $ — $ (302 ) $ — Foreign currency exchange losses (gains), net 174 98 217 533 Other (4 ) — (5 ) — Total other expense (income), net $ (132 ) $ 98 $ (90 ) $ 533

Income Taxes

Income Taxes	9 Months Ended
	Sep. 30, 2018
Income Taxes [Abstract]
Income Taxes	NOTE 12. Income Taxes The following table provides details of income taxes: Three Months Ended September 30, Nine Months Ended September 2018 2017 2018 2017 Income before income taxes $ 8,368 $ 25,663 $ 43,332 $ 48,022 Provision for income taxes $ 1,181 $ 8,294 $ 6,318 $ 14,309 Effective tax rate 14.1 % 32.3 % 14.6 % 29.8 % The income tax provision for the three and nine months ended September 30, 2018 was computed based on the Company’s annual forecast of profit by jurisdiction and forecasted effective tax rate for the year. The changes in the Company’s effective tax rate for the three and nine months ended September 30, 2018 as compared to the same period in 2017 are primarily due to enactment of U.S. tax reform, which provides for a change in the corporate tax rate from 35% to 21%, changes in the mix of forecasted earnings by jurisdictions and the Foreign Derived Intangible Income Deduction. The 2017 Tax Act was enacted on December 22, 2017. The 2017 Tax Act reduces the U.S. federal corporate income tax rate from 35% to 21%, requires companies to pay a one-time transition tax on earnings of certain foreign subsidiaries that were previously tax deferred, provides tax benefits for export sales and creates new taxes on certain foreign sourced earnings. The Company is applying the guidance in SAB 118 when accounting for the enactment-date effects of the 2017 Tax Act. At September 30, 2018, the Company has not completed its accounting for all of the tax effects of the 2017 Tax Act. In all cases, the Company will continue to make and refine its calculations as additional analysis is completed. The Company’s estimates may also be affected as it gains a more thorough understanding of the 2017 Tax Act. These changes could be material to income tax expense. Foreign-Derived Intangible Income: The 2017 Tax Act provides tax incentives to U.S. companies to earn income from the sale, lease or license of goods and services abroad in the form of a deduction for foreign-derived intangible income (“FDII”). FDII is taxed at an effective rate of 13.1% for taxable years beginning after December 31, 2017 and at an effective rate of 16.4% for taxable years beginning after December 31, 2025. The accounting for the deduction for FDII is similar to a special deduction and should be accounted for based on the guidance in ASC 740-10-25-37. The tax benefits for special deductions ordinarily are recognized no earlier than the year in which they are deductible on a tax return. As of September 30, 2018, the Company has made sufficient progress in its calculations to reasonably estimate the effect on its estimated annual effective tax rate. Since a large portion of the Company’s sales are made to non-U.S. customers, this adjustment decreased its effective tax rate by 4.3%. The Company will continue to refine its calculations, which may result in changes to this amount. The Company does not expect other provisions of the 2017 Tax Act, including global intangible low-taxed income (“GILTI”), the new interest expense limitations and base erosion anti-abuse tax (“BEAT”) to have a material impact on the Company’s effective tax rate. Deferred Tax Assets and Liabilities: The Company remeasured certain deferred tax assets and liabilities based on the rates to which they are expected to reverse in the future, which is anticipated to be 21%. The Company recorded a provisional amount of $8.0 million as of December 31, 2017 related to the remeasurement of certain deferred tax balances. Due to the continued refinement of the Company’s transition tax calculation, discussed further below, and the effect it may have on the measurement of NOLs and other carryforwards, the Company will continue to analyze and refine its calculations related to the measurement of these balances. One-Time Transition Tax: The one-time transition tax is based on its total post-1986 earnings and profits (“E&P”), which it has deferred from U.S. income taxes under previous U.S. law. The Company originally recorded a provisional amount for its one-time transition tax liability for all of its foreign subsidiaries, resulting in a transition tax benefit (net of foreign tax credits) of $0.1 million being recorded at December 31, 2017. As the Company continues to refine its E&P analysis, it will refine its calculations of the one-time transition tax, which could affect the measurement of this liability. No additional income taxes have been provided for any remaining undistributed foreign earnings not subject to the transition tax, or any additional outside basis difference inherent in these entities, as these amounts continue to be indefinitely reinvested in foreign operations. The Company currently has a partial valuation allowance recorded against certain foreign and state net operating loss and credit carryforwards where the realizability of such deferred tax assets is substantially in doubt. Each quarter, the Company assesses the likelihood that it will be able to recover its deferred tax assets. The Company considers available evidence, both positive and negative, including forecasted earnings in assessing the need for a valuation allowance. As a result of the Company’s analysis, it concluded that it is more likely than not that a portion of its deferred tax assets will not be realized. Therefore, the Company continues to provide a valuation allowance against certain deferred tax assets. The Company continues to monitor available evidence and may reverse some or all of the remaining valuation allowance in future periods, if appropriate. The Company has a recorded valuation allowance against certain of its deferred tax assets of $2,447 as of September 30, 2018 and December 31, 2017.

Earnings Per Share

Earnings Per Share	9 Months Ended
	Sep. 30, 2018
Earnings Loss Per Share [Abstract]
Earnings Per Share	NOTE 13. Earnings Per Share Basic earnings per share is calculated using the weighted average number of shares of common stock outstanding during the period. Diluted earnings per share is computed in the same manner and also gives effect to all dilutive common equivalent shares outstanding during the period. Potential common shares that would have the effect of increasing diluted earnings per share are considered to be anti-dilutive. In accordance with U.S. GAAP, these shares were not included in calculating diluted earnings per share. The following table sets forth the weighted average number of restricted stock units that have been excluded from the calculation of diluted earnings per share as their effect would have been anti-dilutive: Three Months Ended September 30, Nine Months Ended September 2018 2017 2018 2017 Restricted stock units 7 2 17 9 Total 7 2 17 9 The Company’s basic and diluted earnings per share amounts are as follows: Three Months Ended September 30, Nine Months Ended September 2018 2017 2018 2017 Numerator: Net income $ 7,187 $ 17,369 $ 37,014 $ 33,713 Denominator: Basic earnings per share - weighted average shares outstanding 31,901 31,571 31,807 31,455 Effect of potential dilutive securities: Employee stock options and restricted stock units - dilutive shares 507 599 580 669 Warrant - dilutive shares — — — 2 Diluted earnings per share - weighted average shares outstanding 32,408 32,170 32,387 32,126 Earnings per share: Basic $ 0.23 $ 0.55 $ 1.16 $ 1.07 Diluted $ 0.22 $ 0.54 $ 1.14 $ 1.05

Accumulated Other Comprehensive

Accumulated Other Comprehensive Loss	9 Months Ended
	Sep. 30, 2018
Accumulated Other Comprehensive Loss [Abstract]
Accumulated Other Comprehensive Loss	NOTE 14. Accumulated Other Comprehensive Loss Comprehensive income includes net income, foreign currency translation adjustments and net unrealized gains and losses on available-for-sale debt securities. See the Condensed Consolidated Statements of Comprehensive Income for the effect of the components of comprehensive income on the Company’s net income. The components of accumulated other comprehensive loss, net of tax, are as follows: Foreign currency translation adjustments Net unrealized (gains) losses on marketable securities Accumulated other comprehensive loss (income) Balance at December 31, 2017 $ 1,079 $ 126 $ 1,205 Net current period other comprehensive income 425 (62 ) 363 Reclassifications — — — Balance at September 30, 2018 $ 1,504 $ 64 $ 1,568

Segment Reporting and Geographi

Segment Reporting and Geographic Information	9 Months Ended
	Sep. 30, 2018
Segment Reporting And Geographic Information [Abstract]
Segment Reporting and Geographic Information	NOTE 15. Segment Reporting and Geographic Information The Company is engaged in the design, development, manufacture and support of high-performance control metrology, defect inspection, advanced packaging lithography and data analysis systems used by microelectronics device manufacturers. The Company and its subsidiaries currently operate in a single operating segment: the design, development, manufacture and support of high-performance process control defect inspection and metrology, advanced packaging lithography and process control software systems used by microelectronics device manufacturers. Therefore the Company has one reportable segment. The Company’s chief operating decision maker is the Chief Executive Officer (the “CEO”). The CEO allocates resources and assesses performance of the business and other activities at the reportable segment level. The following table lists the different sources of revenue: Three Months Ended Nine Months Ended September 30, September 30, 2018 2017 2018 2017 Systems and Software: Process control $ 41,164 68 % $ 43,821 65 % $ 145,458 69 % $ 135,408 70 % Lithography 2,791 5 % 7,010 11 % 14,712 7 % 10,560 5 % Software licensing, support and maintenance 6,877 11 % 6,053 9 % 21,879 10 % 20,447 10 % Parts 7,141 12 % 7,101 11 % 20,884 10 % 20,779 11 % Services 2,459 4 % 2,935 4 % 8,071 4 % 7,823 4 % Total revenue $ 60,432 100 % $ 66,920 100 % $ 211,004 100 % $ 195,017 100 % For geographical revenue reporting, revenue is attributed to the geographic location to which the product is shipped. Revenue by geographic region is as follows: Three Months Ended Nine Months Ended September 30, September 30, 2018 2017 2018 2017 Revenue from third parties: United States $ 11,476 $ 7,666 $ 29,344 $ 25,856 Taiwan 10,233 17,300 35,643 49,960 Japan 4,134 6,268 14,082 12,944 China 11,547 4,151 52,866 24,156 South Korea 10,977 10,852 44,581 36,099 Singapore 4,644 4,664 11,985 9,875 Other Asia 1,102 1,690 3,520 3,249 Germany 3,527 4,488 8,668 12,357 Other Europe 2,792 9,841 10,315 20,521 Total revenue $ 60,432 $ 66,920 $ 211,004 $ 195,017 The following customer accounted for more than 10% of total revenue for the indicated periods: Nine Months Ended September 30, 2018 2017 Customer A 10.5 % 8.2 %

Share Repurchase Authorization

Share Repurchase Authorization	9 Months Ended
	Sep. 30, 2018
Share Repurchase Program [Abstract]
Share Repurchase Authorization	NOTE 16. Share Repurchase Authorization In January 2015, the Board of Directors authorized the Company to repurchase up to 3,000 shares of the Company’s common stock with no established end date. The authorization allows for repurchases to be made in the open market or through negotiated transactions from time to time. During the three and nine months ended September 30, 2018, the Company repurchased 2 shares of common stock pursuant to the share repurchase authorization. At September 30, 2018, there were 709 shares available for future stock repurchases under this share repurchase authorization. Shares of common stock purchased under the share repurchase authorization are retired.

Revenue (Tables)

Revenue (Tables)	9 Months Ended
	Sep. 30, 2018
Revenue Recognition [Abstract]
Schedule of Disaggregation of Revenue	The following table presents the Company’s revenue disaggregated by revenue source: Three Months Ended Nine Months Ended September 30, September 30, 2018 2017 2018 2017 Systems $ 43,955 $ 50,831 $ 160,170 $ 145,968 Software licensing, support and maintenance 6,877 6,053 21,879 20,447 Parts 7,141 7,101 20,884 20,779 Services 2,459 2,935 8,071 7,823 Total revenue $ 60,432 $ 66,920 $ 211,004 $ 195,017 The following table represents a disaggregation of revenue by timing of revenue: Three Months Ended Nine Months Ended September 30, September 30, 2018 2018 Point-in-time $ 56,185 $ 198,864 Over-time 4,247 12,140 Total revenue $ 60,432 $ 211,004
Schedule of Changes in Deferred Revenue	Changes in deferred revenue were as follows: Three Months Ended Nine Months Ended September 30, September 30, 2018 2018 Balance, beginning of the period $ 8,799 $ 7,206 Deferral of revenue 4,354 15,002 Recognition of deferred revenue (4,449 ) (13,504 ) Balance, ending of the period $ 8,704 $ 8,704

Fair Value Measurements - (Tabl

Fair Value Measurements - (Tables)	9 Months Ended
	Sep. 30, 2018
Fair Value Measurements [Abstract]
Fair Value Measurements, Recurring and Nonrecurring	The following tables provide the assets and liabilities carried at fair value measured on a recurring basis at September 30, 2018 and December 31, 2017: Fair Value Measurements Using Carrying Value Quoted Prices in Active Markets for Identical Assets (Level 1) Significant Other Observable Inputs (Level 2) Significant Unobservable Inputs (Level 3) September 30, 2018 Assets: Available-for-sale debt securities: Municipal notes and bonds $ 70,005 $ — $ 70,005 $ — Foreign currency forward exchange contracts 156 — 156 — Total assets $ 70,161 $ — $ 70,161 $ — Liabilities: Contingent consideration - acquisitions 2,139 — — 2,139 Total liabilities $ 2,139 $ — $ — $ 2,139 December 31, 2017 Assets: Available-for-sale debt securities: Municipal notes and bonds $ 109,589 $ — $ 109,589 $ — Foreign currency forward exchange contracts 45 — 45 — Total assets $ 109,634 $ — $ 109,634 $ — Liabilities: Contingent consideration - acquisitions $ 2,593 $ — $ — $ 2,593 Total liabilities $ 2,593 $ — $ — $ 2,593
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation	This table presents a reconciliation of all liabilities measured at fair value on a recurring basis using significant unobservable inputs (Level 3) for the nine months ended September 30, 2018: Fair Value Measurements Using Significant Unobservable Inputs (Level 3) Balance at December 31, 2017 $ 2,593 Additions — Total loss included in selling, general and administrative expense 603 Payments (1,057 ) Transfers into (out of) Level 3 — Balance at September 30, 2018 $ 2,139

Marketable Securities - (Tables

Marketable Securities - (Tables)	9 Months Ended
	Sep. 30, 2018
Marketable Securities [Abstract]
Schedule of Marketable Securities by Category	At September 30, 2018 and December 31, 2017, marketable securities are categorized as follows: Amortized Cost Gross Unrealized Holding Gains Gross Unrealized Holding Losses Fair Value September 30, 2018 Municipal notes and bonds $ 70,092 $ — $ 87 $ 70,005 Total marketable securities $ 70,092 $ — $ 87 $ 70,005 December 31, 2017 Municipal notes and bonds $ 109,750 $ — $ 161 $ 109,589 Total marketable securities $ 109,750 $ — $ 161 $ 109,589
Schedule of Amortized Cost and Estimated Fair Value of Marketable Securities Classified by Maturity Date	The amortized cost and estimated fair value of marketable securities classified by the maturity date listed on the security, regardless of the Condensed Consolidated Balance Sheet classification, are as follows at September 30, 2018 and December 31, 2017: September 30, 2018 December 31, 2017 Amortized Cost Fair Value Amortized Cost Fair Value Due within one year $ 63,901 $ 63,831 $ 104,742 $ 104,605 Due after one through five years 6,191 6,174 5,008 4,984 Due after five through ten years — — — — Due after ten years — — — — Total marketable securities $ 70,092 $ 70,005 $ 109,750 $ 109,589
Summary of Estimated Fair Value and Gross Unrealized Holding Losses of Marketable Securities in Unrealized Loss Position	The following table summarizes the estimated fair value and gross unrealized holding losses of marketable securities, aggregated by investment instrument and period of time in an unrealized loss position, at September 30, 2018 and December 31, 2017: Unrealized Loss Position For Less Than 12 Months Unrealized Loss Position For Greater Than 12 Months Fair Value Gross Unrealized Losses Fair Value Gross Unrealized Losses September 30, 2018 Municipal notes and bonds $ 50,097 $ 70 $ 7,172 $ 17 Total $ 50,097 $ 70 $ 7,172 $ 17 December 31, 2017 Municipal notes and bonds $ 98,805 $ 161 $ — $ — Total $ 98,805 $ 161 $ — $ —

Derivative Instruments and He_2

Derivative Instruments and Hedging Activities (Tables)	9 Months Ended
	Sep. 30, 2018
Derivative Instruments And Hedging Activities Disclosure [Abstract]
Forward Contracts and Related Fair Values	The dollar equivalent of the U.S. dollar forward exchange contracts and related fair values as of September 30, 2018 and December 31, 2017 were as follows: September 30, 2018 December 31, 2017 Notional amount $ 5,709 $ 8,417 Fair value of asset $ 156 $ 45

Purchased Intangible Assets - (

Purchased Intangible Assets - (Tables)	9 Months Ended
	Sep. 30, 2018
Purchased Intangible Assets [Abstract]
Schedule of Purchased Intangible Assets	Purchased intangible assets as of September 30, 2018 and December 31, 2017 are as follows: Gross Carrying Amount Accumulated Amortization Net September 30, 2018 Finite-lived intangibles: Developed technology $ 66,127 $ 59,396 $ 6,731 Customer and distributor relationships 9,561 9,016 545 Trade names 4,361 3,851 510 Total identifiable intangible assets $ 80,049 $ 72,263 $ 7,786 December 31, 2017 Finite-lived intangibles: Developed technology $ 65,827 $ 58,522 $ 7,305 Customer and distributor relationships 9,560 8,818 742 Trade names 4,361 3,776 585 Total identifiable intangible assets $ 79,748 $ 71,116 $ 8,632

Balance Sheet Details (Tables)

Balance Sheet Details (Tables)	9 Months Ended
	Sep. 30, 2018
Balance Sheet Detail [Abstract]
Schedule of Inventories	Inventories are comprised of the following: September 30, 2018 December 31, 2017 Materials $ 55,856 $ 39,765 Work-in-process 24,467 20,923 Finished goods 11,068 6,833 Total inventories $ 91,391 $ 67,521
Schedule of Property, Plant and Equipment, Net	Property, plant and equipment, net is comprised of the following: September 30, 2018 December 31, 2017 Land and building $ 2,584 $ 2,584 Machinery and equipment 29,370 29,870 Furniture and fixtures 3,267 3,201 Computer equipment and software 6,749 5,444 Leasehold improvements 9,494 9,472 51,464 50,571 Accumulated depreciation (34,701 ) (33,229 ) Total property, plant and equipment, net $ 16,763 $ 17,342
Schedule of Other Assets	Other assets is comprised of the following: September 30, 2018 December 31, 2017 Deferred income taxes $ 14,896 $ 14,879 Convertible note receivable $ 1,000 $ — Other 499 492 Total other assets $ 16,395 $ 15,371
Schedule of Other Current Liabilities	Other current liabilities is comprised of the following: September 30, 2018 December 31, 2017 Intangible asset acquisition - Stella Alliance $ 250 $ 100 Contingent consideration - acquisitions 781 634 Customer deposits 877 5,561 Other 6,014 2,989 Total other current liabilities $ 7,922 $ 9,284
Schedule of Other Non-Current Liabilities	Other non-current liabilities is comprised of the following: September 30, 2018 December 31, 2017 Unrecognized tax benefits (including interest) $ 4,698 $ 4,660 Contingent consideration - acquisitions 1,358 1,959 Deferred revenue 1,140 983 Other 2,977 2,859 Total other non-current liabilities $ 10,173 $ 10,461

Commitments and Contingencies (

Commitments and Contingencies (Tables)	9 Months Ended
	Sep. 30, 2018
Commitments And Contingencies [Abstract]
Schedule of Changes in Warranty Reserves	Changes in the Company’s warranty reserves are as follows: Nine Months Ended September 30, 2018 2017 Balance, beginning of the period $ 2,427 $ 1,788 Accruals 2,720 2,511 Usage (2,589 ) (2,025 ) Balance, end of the period $ 2,558 $ 2,274

Share-Based Compensation - (Tab

Share-Based Compensation - (Tables)	9 Months Ended
	Sep. 30, 2018
Share Based Compensation [Abstract]
Summary of Unvested Restricted Stock Unit Activity	A summary of the activity with respect to the Company’s unvested restricted stock units during the nine months ended September 30, 2018 is as follows: Number of Shares Weighted Average Grant Date Fair Value Nonvested at December 31, 2017 1,014 $ 14.88 Granted 274 $ 28.25 Vested (300 ) $ 14.22 Forfeited (68 ) $ 17.50 Nonvested at September 30, 2018 920 $ 18.89

Other Expense (Income), net (Ta

Other Expense (Income), net (Tables)	9 Months Ended
	Sep. 30, 2018
Other Income Expense [Abstract]
Schedule of Other Expense (Income), Net	Three Months Ended September 30, Nine Months Ended September 2018 2017 2018 2017 Gain on casualty insurance claim $ (302 ) $ — $ (302 ) $ — Foreign currency exchange losses (gains), net 174 98 217 533 Other (4 ) — (5 ) — Total other expense (income), net $ (132 ) $ 98 $ (90 ) $ 533

Income Taxes - (Tables)

Income Taxes - (Tables)	9 Months Ended
	Sep. 30, 2018
Income Taxes [Abstract]
Schedule of Effective Tax Rate	The following table provides details of income taxes: Three Months Ended September 30, Nine Months Ended September 2018 2017 2018 2017 Income before income taxes $ 8,368 $ 25,663 $ 43,332 $ 48,022 Provision for income taxes $ 1,181 $ 8,294 $ 6,318 $ 14,309 Effective tax rate 14.1 % 32.3 % 14.6 % 29.8 %

Earnings Per Share - (Tables)

Earnings Per Share - (Tables)	9 Months Ended
	Sep. 30, 2018
Earnings Per Share [Abstract]
Schedule of Anti-dilutive Securities Excluded from Computation of Earnings Per Share	The following table sets forth the weighted average number of restricted stock units that have been excluded from the calculation of diluted earnings per share as their effect would have been anti-dilutive: Three Months Ended September 30, Nine Months Ended September 2018 2017 2018 2017 Restricted stock units 7 2 17 9 Total 7 2 17 9
Schedule of Earnings Per Share, Basic and Diluted	The Company’s basic and diluted earnings per share amounts are as follows: Three Months Ended September 30, Nine Months Ended September 2018 2017 2018 2017 Numerator: Net income $ 7,187 $ 17,369 $ 37,014 $ 33,713 Denominator: Basic earnings per share - weighted average shares outstanding 31,901 31,571 31,807 31,455 Effect of potential dilutive securities: Employee stock options and restricted stock units - dilutive shares 507 599 580 669 Warrant - dilutive shares — — — 2 Diluted earnings per share - weighted average shares outstanding 32,408 32,170 32,387 32,126 Earnings per share: Basic $ 0.23 $ 0.55 $ 1.16 $ 1.07 Diluted $ 0.22 $ 0.54 $ 1.14 $ 1.05

Accumulated Other Comprehensi_2

Accumulated Other Comprehensive Loss (Tables)	9 Months Ended
	Sep. 30, 2018
Accumulated Other Comprehensive Loss [Abstract]
Components of Accumulated Other Comprehensive Loss, Net of Tax	The components of accumulated other comprehensive loss, net of tax, are as follows: Foreign currency translation adjustments Net unrealized (gains) losses on marketable securities Accumulated other comprehensive loss (income) Balance at December 31, 2017 $ 1,079 $ 126 $ 1,205 Net current period other comprehensive income 425 (62 ) 363 Reclassifications — — — Balance at September 30, 2018 $ 1,504 $ 64 $ 1,568

Segment Reporting and Geograp_2

Segment Reporting and Geographic Information - (Tables)	9 Months Ended
	Sep. 30, 2018
Segment Reporting And Geographic Information [Abstract]
Schedule of Revenue from External Customers by Products and Services	The following table lists the different sources of revenue: Three Months Ended Nine Months Ended September 30, September 30, 2018 2017 2018 2017 Systems and Software: Process control $ 41,164 68 % $ 43,821 65 % $ 145,458 69 % $ 135,408 70 % Lithography 2,791 5 % 7,010 11 % 14,712 7 % 10,560 5 % Software licensing, support and maintenance 6,877 11 % 6,053 9 % 21,879 10 % 20,447 10 % Parts 7,141 12 % 7,101 11 % 20,884 10 % 20,779 11 % Services 2,459 4 % 2,935 4 % 8,071 4 % 7,823 4 % Total revenue $ 60,432 100 % $ 66,920 100 % $ 211,004 100 % $ 195,017 100 %
Schedule of Revenue from External Customers Attributed to Foreign Countries by Geographic Area	For geographical revenue reporting, revenue is attributed to the geographic location to which the product is shipped. Revenue by geographic region is as follows: Three Months Ended Nine Months Ended September 30, September 30, 2018 2017 2018 2017 Revenue from third parties: United States $ 11,476 $ 7,666 $ 29,344 $ 25,856 Taiwan 10,233 17,300 35,643 49,960 Japan 4,134 6,268 14,082 12,944 China 11,547 4,151 52,866 24,156 South Korea 10,977 10,852 44,581 36,099 Singapore 4,644 4,664 11,985 9,875 Other Asia 1,102 1,690 3,520 3,249 Germany 3,527 4,488 8,668 12,357 Other Europe 2,792 9,841 10,315 20,521 Total revenue $ 60,432 $ 66,920 $ 211,004 $ 195,017
Schedule of Revenue by Major Customers by Reporting Segments	The following customer accounted for more than 10% of total revenue for the indicated periods: Nine Months Ended September 30, 2018 2017 Customer A 10.5 % 8.2 %

Revenue - Schedule of Disaggreg

Revenue - Schedule of Disaggregation of Revenue by Revenue Source (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Disaggregation Of Revenue [Line Items]
Total revenue	$ 60,432	$ 66,920	$ 211,004	$ 195,017
Systems Revenue [Member]
Disaggregation Of Revenue [Line Items]
Total revenue	43,955	50,831	160,170	145,968
Software Revenue [Member]
Disaggregation Of Revenue [Line Items]
Total revenue	6,877	6,053	21,879	20,447
Parts Revenue [Member]
Disaggregation Of Revenue [Line Items]
Total revenue	7,141	7,101	20,884	20,779
Service Revenue [Member]
Disaggregation Of Revenue [Line Items]
Total revenue	$ 2,459	$ 2,935	$ 8,071	$ 7,823

Revenue - Schedule of Disaggr_2

Revenue - Schedule of Disaggregation of Revenue by Timing of Revenue (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Disaggregation Of Revenue [Line Items]
Total revenue	$ 60,432	$ 66,920	$ 211,004	$ 195,017
Transferred at Point in Time [Member]
Disaggregation Of Revenue [Line Items]
Total revenue	56,185		198,864
Transferred over Time [Member]
Disaggregation Of Revenue [Line Items]
Total revenue	$ 4,247		$ 12,140

Revenue - Additional Informatio

Revenue - Additional Information (Details) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2018	Jun. 30, 2018	Dec. 31, 2017
Disaggregation Of Revenue [Line Items]
Deferred revenue	$ 8,704	$ 8,799	$ 7,206
Systems Revenue [Member]
Disaggregation Of Revenue [Line Items]
Number of days for payment due from customer	30 days
Software Revenue [Member]
Disaggregation Of Revenue [Line Items]
Number of days for payment due from customer	30 days
Parts Revenue [Member]
Disaggregation Of Revenue [Line Items]
Number of days for payment due from customer	30 days
Service Revenue [Member]
Disaggregation Of Revenue [Line Items]
Number of days for payment due from customer	30 days
Minimum [Member] | Systems Revenue [Member]
Disaggregation Of Revenue [Line Items]
Percentage of invoice amount due	80.00%
Assurance warranty period against defects	12 months
Maximum [Member] | Systems Revenue [Member]
Disaggregation Of Revenue [Line Items]
Percentage of invoice amount due	90.00%
Assurance warranty period against defects	15 months

Revenue - Schedule of Changes i

Revenue - Schedule of Changes in Deferred Revenue (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
	Sep. 30, 2018	Sep. 30, 2018
Deferred Revenue Disclosure [Abstract]
Balance, beginning of the period	$ 8,799	$ 7,206
Deferral of revenue	4,354	15,002
Recognition of deferred revenue	(4,449)	(13,504)
Balance, ending of the period	$ 8,704	$ 8,704

Fair Value Measurements - Sched

Fair Value Measurements - Schedule of Assets and Liabilities Carried at Fair Value Measured on a Recurring Basis (Details) - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Municipal notes and bonds	$ 70,005	$ 109,589
Foreign currency forward exchange contracts	156	45
Total assets	70,161	109,634
Contingent consideration - acquisitions	2,139	2,593
Total liabilities	2,139	2,593
Quoted Prices in Active Markets for Identical Assets (Level 1) [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Municipal notes and bonds	0	0
Foreign currency forward exchange contracts	0	0
Total assets	0	0
Contingent consideration - acquisitions	0	0
Total liabilities	0	0
Significant Other Observable Inputs (Level 2) [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Municipal notes and bonds	70,005	109,589
Foreign currency forward exchange contracts	156	45
Total assets	70,161	109,634
Contingent consideration - acquisitions	0	0
Total liabilities	0	0
Significant Unobservable Inputs (Level 3) [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Municipal notes and bonds	0	0
Foreign currency forward exchange contracts	0	0
Total assets	0	0
Contingent consideration - acquisitions	2,139	2,593
Total liabilities	$ 2,139	$ 2,593

Fair Value Measurements - Addit

Fair Value Measurements - Additional Information (Details)	Sep. 30, 2018	Sep. 30, 2017
Significant Unobservable Inputs (Level 3) [Member] | Measurement Input Discount Rate [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Estimated discount rates	0.094	0.086

Fair Value Measurements - Recon

Fair Value Measurements - Reconciliation for All Liabilities Measured at Fair Value on Recurring Basis Using Significant Unobservable Inputs (level 3) (Details) $ in Thousands	9 Months Ended
	Sep. 30, 2018USD ($)
Fair Value Measurements [Abstract]
Balance at December 31, 2017	$ 2,593
Additions	0
Total loss included in selling, general and administrative expense	603
Payments	(1,057)
Transfers into (out of) Level 3	0
Balance at September 30, 2018	$ 2,139

Marketable Securities - Schedul

Marketable Securities - Schedule of Marketable Securities by Category (Details) - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	$ 70,092	$ 109,750
Gross Unrealized Holding Gains	0	0
Gross Unrealized Holding Losses	87	161
Fair Value	70,005	109,589
Municipal Notes and Bonds [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	70,092	109,750
Gross Unrealized Holding Gains	0	0
Gross Unrealized Holding Losses	87	161
Fair Value	$ 70,005	$ 109,589

Marketable Securities - Sched_2

Marketable Securities - Schedule of Amortized Cost and Estimated Fair Value of Marketable Securities Classified by Maturity Date (Details) - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017
Available For Sale Securities Debt Maturities Fair Value [Abstract]
Amortized Cost, Due within one year	$ 63,901	$ 104,742
Amortized Cost, Due after one through five years	6,191	5,008
Amortized Cost, Due after five through ten years	0	0
Amortized Cost, Due after ten years	0	0
Amortized Cost, Total marketable securities	70,092	109,750
Fair Value, Due within one year	63,831	104,605
Fair Value, Due after one through five years	6,174	4,984
Fair Value, Due after five through ten years	0	0
Fair Value, Due after ten years	0	0
Fair Value, Total marketable securities	$ 70,005	$ 109,589

Marketable Securities - Summary

Marketable Securities - Summary of Estimated Fair Value and Gross Unrealized Holding Losses of Marketable Securities in Unrealized Loss Position (Details) - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017
Schedule of Available-for-sale Securities [Line Items]
Unrealized Loss Position For Less Than 12 Months, Fair Value	$ 50,097	$ 98,805
Unrealized Loss Position For Less Than 12 Months, Gross Unrealized Losses	(70)	(161)
Unrealized Loss Position For Greater Than 12 Months, Fair Value	7,172	0
Unrealized Loss Position For Greater Than 12 Months, Gross Unrealized Losses	(17)	0
Municipal Notes and Bonds [Member]
Schedule of Available-for-sale Securities [Line Items]
Unrealized Loss Position For Less Than 12 Months, Fair Value	50,097	98,805
Unrealized Loss Position For Less Than 12 Months, Gross Unrealized Losses	(70)	(161)
Unrealized Loss Position For Greater Than 12 Months, Fair Value	7,172	0
Unrealized Loss Position For Greater Than 12 Months, Gross Unrealized Losses	$ (17)	$ 0

Convertible Note Receivable - A

Convertible Note Receivable - Additional Information (Details) - USD ($)	May 31, 2018	Sep. 30, 2018	Dec. 31, 2017
Loans And Leases Receivable Disclosure [Line Items]
Convertible notes receivable		$ 1,000,000	$ 0
Accrued interest		$ 4,000
Convertible Loan Agreement [Member] | Simax Precision Technologies Limited [Member]
Loans And Leases Receivable Disclosure [Line Items]
Funds available in multiple promissory notes	$ 15,000,000
Convertible notes rate of interest	4.25%
Term of repayment for principal amount and outstanding interest	3 years

Derivative Instruments and He_3

Derivative Instruments and Hedging Activities - Additional Information (Details) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017
Derivative Instruments And Hedging Activities Disclosure [Abstract]
Increase (decrease) in fair value of forward contracts	$ 111	$ (251)

Derivative Instruments and He_4

Derivative Instruments and Hedging Activities - Forward Contracts and Related Fair Values (Details) - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017
Derivative Instruments And Hedging Activities Disclosure [Abstract]
Notional amount	$ 5,709	$ 8,417
Fair value of asset	$ 156	$ 45

Purchase Intangible Assets - (D

Purchase Intangible Assets - (Details) - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017
Finite Lived Intangible Assets [Line Items]
Finite-lived intangibles, Gross Carrying Amount	$ 80,049	$ 79,748
Finite-lived intangibles, Accumulated Amortization	72,263	71,116
Finite-lived intangibles, Net	7,786	8,632
Developed Technology [Member]
Finite Lived Intangible Assets [Line Items]
Finite-lived intangibles, Gross Carrying Amount	66,127	65,827
Finite-lived intangibles, Accumulated Amortization	59,396	58,522
Finite-lived intangibles, Net	6,731	7,305
Customer and Distributor Relationships [Member]
Finite Lived Intangible Assets [Line Items]
Finite-lived intangibles, Gross Carrying Amount	9,561	9,560
Finite-lived intangibles, Accumulated Amortization	9,016	8,818
Finite-lived intangibles, Net	545	742
Trade Names [Member]
Finite Lived Intangible Assets [Line Items]
Finite-lived intangibles, Gross Carrying Amount	4,361	4,361
Finite-lived intangibles, Accumulated Amortization	3,851	3,776
Finite-lived intangibles, Net	$ 510	$ 585

Purchase Intangible Assets - Ad

Purchase Intangible Assets - Additional Information (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Purchased Intangible Assets [Abstract]
Amortization	$ 384	$ 506	$ 1,147	$ 1,516
Future amortization expense, Remainder of 2018	386		386
Future amortization expense, 2019	1,544		1,544
Future amortization expense, 2020	1,341		1,341
Future amortization expense, 2021	594		594
Future amortization expense, 2022	527		527
Future amortization expense, 2023	$ 511		$ 511

Balance Sheet Details - Schedul

Balance Sheet Details - Schedule of Inventories (Details) - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017
Inventory Details [Abstract]
Materials	$ 55,856	$ 39,765
Work-in-process	24,467	20,923
Finished goods	11,068	6,833
Total inventories	$ 91,391	$ 67,521

Balance Sheet Details - Additio

Balance Sheet Details - Additional Information (Details) - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017
Balance Sheet Detail [Abstract]
Inventory valuation reserves	$ 12,164	$ 13,035

Balance Sheet Details - Sched_2

Balance Sheet Details - Schedule of Property, Plant and Equipment, Net (Details) - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017
Property Plant And Equipment [Line Items]
Property, plant and equipment, gross	$ 51,464	$ 50,571
Accumulated depreciation	(34,701)	(33,229)
Total property, plant and equipment, net	16,763	17,342
Land and Building [Member]
Property Plant And Equipment [Line Items]
Property, plant and equipment, gross	2,584	2,584
Machinery and Equipment [Member]
Property Plant And Equipment [Line Items]
Property, plant and equipment, gross	29,370	29,870
Furniture and Fixtures [Member]
Property Plant And Equipment [Line Items]
Property, plant and equipment, gross	3,267	3,201
Computer Equipment and Software [Member]
Property Plant And Equipment [Line Items]
Property, plant and equipment, gross	6,749	5,444
Leasehold Improvements [Member]
Property Plant And Equipment [Line Items]
Property, plant and equipment, gross	$ 9,494	$ 9,472

Balance Sheet Details - Sched_3

Balance Sheet Details - Schedule of Other Assets (Details) - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017
Other Assets [Abstract]
Deferred income taxes	$ 14,896	$ 14,879
Convertible notes receivable	1,000	0
Other	499	492
Total other assets	$ 16,395	$ 15,371

Balance Sheet Details - Sched_4

Balance Sheet Details - Schedule of Other Current Liabilities (Details) - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017
Other Liabilities Current [Abstract]
Intangible asset acquisition - Stella Alliance	$ 250	$ 100
Contingent consideration - acquisitions	781	634
Customer deposits	877	5,561
Other	6,014	2,989
Total other current liabilities	$ 7,922	$ 9,284

Balance Sheet Details - Sched_5

Balance Sheet Details - Schedule of Other Non-Current Liabilities (Details) - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017
Other Liabilities Noncurrent [Abstract]
Unrecognized tax benefits (including interest)	$ 4,698	$ 4,660
Contingent consideration - acquisitions	1,358	1,959
Deferred revenue	1,140	983
Other	2,977	2,859
Total other non-current liabilities	$ 10,173	$ 10,461

Commitments and Contingencies -

Commitments and Contingencies - Additional Information (Details) $ in Millions	9 Months Ended
	Sep. 30, 2018USD ($)
Commitments And Contingencies [Line Items]
Percentage of maximum borrowing capacity of value of eligible securities	70.00%
Available line of credit	$ 102
Available interest rate on line of credit	3.80%
Minimum [Member]
Commitments And Contingencies [Line Items]
Warranty period	12 months
Maximum [Member]
Commitments And Contingencies [Line Items]
Warranty period	15 months

Commitments and Contingencies_2

Commitments and Contingencies - Schedule of Changes in Warranty Reserves (Details) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017
Commitments And Contingencies [Abstract]
Balance, beginning of the period	$ 2,427	$ 1,788
Accruals	2,720	2,511
Usage	(2,589)	(2,025)
Balance, end of the period	$ 2,558	$ 2,274

Share-Based Compensation - Summ

Share-Based Compensation - Summary of Unvested Restricted Stock Unit Activity (Details)	9 Months Ended
	Sep. 30, 2018$ / sharesshares
Restricted Stock Units Activity [Abstract]
Number of Shares, Nonvested beginning balance | shares	1,014
Number of Shares, Granted | shares	274
Number of Shares, Vested | shares	(300)
Number of Shares, Forfeited | shares	(68)
Number of Shares, Nonvested ending balance | shares	920
Weighted Average Grant Date Fair Value, Nonvested beginning balance | $ / shares	$ 14.88
Weighted Average Grant Date Fair Value, Granted | $ / shares	28.25
Weighted Average Grant Date Fair Value, Vested | $ / shares	14.22
Weighted Average Grant Date Fair Value, Forfeited | $ / shares	17.50
Weighted Average Grant Date Fair Value, Nonvested ending balance | $ / shares	$ 18.89

Share-Based Compensation - Addi

Share-Based Compensation - Additional Information (Details) - USD ($)	9 Months Ended	12 Months Ended
	Sep. 30, 2018	Dec. 31, 2017
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Market performance-based restricted stock units granted	274
Maximum potential market performance-based restricted stock units to vest	105
Estimated fair value per share of the market performance-based restricted stock units	$ 30.76
Maximum potential market performance-based restricted stock units to vest percentage	200.00%
Market performance-based restricted stock units vesting period	3 years
Total unrecognized compensation cost related to restricted stock units granted	$ 11,088	$ 9,420
Unrecognized compensation cost related to restricted stock units, weighted average period	2 years 1 month 6 days	2 years 2 months 12 days
Market Performance Based Restricted Stock Units [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Market performance-based restricted stock units granted	53

Other Expense (Income), Net - S

Other Expense (Income), Net - Schedule of Other Expense (Income), Net (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Other Income Expense [Abstract]
Gain on casualty insurance claim	$ (302)	$ 0	$ (302)	$ 0
Foreign currency exchange losses (gains), net	174	98	217	533
Other	(4)	0	(5)	0
Total other expense (income), net	$ (132)	$ 98	$ (90)	$ 533

Income Taxes - Schedule of Effe

Income Taxes - Schedule of Effective Tax Rate (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Income Taxes [Abstract]
Income before income taxes	$ 8,368	$ 25,663	$ 43,332	$ 48,022
Provision for income taxes	$ 1,181	$ 8,294	$ 6,318	$ 14,309
Effective tax rate	14.10%	32.30%	14.60%	29.80%

Income Taxes - Additional Infor

Income Taxes - Additional Information (Details) $ in Thousands	9 Months Ended	12 Months Ended
	Sep. 30, 2018USD ($)	Dec. 31, 2017USD ($)	Dec. 31, 2025
Income Taxes [Abstract]
Valuation allowance against deferred tax assets	$ 2,447	$ 2,447
Tax cuts and jobs act of 2017, incomplete accounting, change in tax rate, deferred tax assets, provisional income tax benefit		8,000
Transition tax expense		$ 100
Change in effective tax rate due to FDII	4.3
Effective income tax rate reconciliation, at federal statutory income tax rate, percent	21.00%	35.00%
Foreign derived intangible income (FDII) effective tax rate		13.1	16.4

Earnings Per Share - Schedule o

Earnings Per Share - Schedule of Anti-dilutive Securities Excluded from Computation of Earnings Per Share (Details) - shares shares in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of earnings per share, amount	7	2	17	9
Restricted Stock Units (RSUs) [Member]
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of earnings per share, amount	7	2	17	9

Earnings Per Share - Schedule_2

Earnings Per Share - Schedule of Earnings Per Share, Basic and Diluted (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Earnings Per Share [Abstract]
Net income	$ 7,187	$ 17,369	$ 37,014	$ 33,713
Basic earnings per share - weighted average shares outstanding	31,901	31,571	31,807	31,455
Employee stock options and restricted stock units - dilutive shares	507	599	580	669
Warrant - dilutive shares	0	0	0	2
Diluted earnings per share - weighted average shares outstanding	32,408	32,170	32,387	32,126
Basic	$ 0.23	$ 0.55	$ 1.16	$ 1.07
Diluted	$ 0.22	$ 0.54	$ 1.14	$ 1.05

Accumulated Other Comprehensi_3

Accumulated Other Comprehensive Loss - Components of Accumulated Other Comprehensive Loss, Net of Tax (Details) $ in Thousands	9 Months Ended
	Sep. 30, 2018USD ($)
Accumulated Other Comprehensive Income Loss [Line Items]
Balance at December 31, 2017	$ 333,154
Balance at September 30, 2018	374,156
Foreign Currency Translation Adjustments [Member]
Accumulated Other Comprehensive Income Loss [Line Items]
Balance at December 31, 2017	1,079
Net current period other comprehensive income	425
Reclassifications	0
Balance at September 30, 2018	1,504
Net Unrealized (Gains) Losses on Marketable Securities [Member]
Accumulated Other Comprehensive Income Loss [Line Items]
Balance at December 31, 2017	126
Net current period other comprehensive income	(62)
Reclassifications	0
Balance at September 30, 2018	64
Accumulated Other Comprehensive Loss (Income) [Member]
Accumulated Other Comprehensive Income Loss [Line Items]
Balance at December 31, 2017	1,205
Net current period other comprehensive income	363
Reclassifications	0
Balance at September 30, 2018	$ 1,568

Segment Reporting and Geograp_3

Segment Reporting and Geographic Information - Additional Information (Details)	9 Months Ended
	Sep. 30, 2018Segment
Segment Reporting [Abstract]
Number of reportable segments	1

Segment Reporting and Geograp_4

Segment Reporting and Geographic Information - Schedule of Revenue from External Customers by Products and Services (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Segment Reporting Information [Line Items]
Revenues	$ 60,432	$ 66,920	$ 211,004	$ 195,017
Sales [Member] | Product [Member]
Segment Reporting Information [Line Items]
Concentration risk, percentage	100.00%	100.00%	100.00%	100.00%
Process Control [Member]
Segment Reporting Information [Line Items]
Revenues	$ 41,164	$ 43,821	$ 145,458	$ 135,408
Process Control [Member] | Sales [Member] | Product [Member]
Segment Reporting Information [Line Items]
Concentration risk, percentage	68.00%	65.00%	69.00%	70.00%
Lithography [Member]
Segment Reporting Information [Line Items]
Revenues	$ 2,791	$ 7,010	$ 14,712	$ 10,560
Lithography [Member] | Sales [Member] | Product [Member]
Segment Reporting Information [Line Items]
Concentration risk, percentage	5.00%	11.00%	7.00%	5.00%
Software Revenue [Member]
Segment Reporting Information [Line Items]
Revenues	$ 6,877	$ 6,053	$ 21,879	$ 20,447
Software Revenue [Member] | Sales [Member] | Product [Member]
Segment Reporting Information [Line Items]
Concentration risk, percentage	11.00%	9.00%	10.00%	10.00%
Parts [Member]
Segment Reporting Information [Line Items]
Revenues	$ 7,141	$ 7,101	$ 20,884	$ 20,779
Parts [Member] | Sales [Member] | Product [Member]
Segment Reporting Information [Line Items]
Concentration risk, percentage	12.00%	11.00%	10.00%	11.00%
Services [Member]
Segment Reporting Information [Line Items]
Revenues	$ 2,459	$ 2,935	$ 8,071	$ 7,823
Services [Member] | Sales [Member] | Product [Member]
Segment Reporting Information [Line Items]
Concentration risk, percentage	4.00%	4.00%	4.00%	4.00%

Segment Reporting and Geograp_5

Segment Reporting and Geographic Information - Schedule of Revenue from External Customers Attributed to Foreign Countries by Geographic Area (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Segment Reporting Information [Line Items]
Revenues	$ 60,432	$ 66,920	$ 211,004	$ 195,017
United States [Member]
Segment Reporting Information [Line Items]
Revenues	11,476	7,666	29,344	25,856
Taiwan [Member]
Segment Reporting Information [Line Items]
Revenues	10,233	17,300	35,643	49,960
Japan [Member]
Segment Reporting Information [Line Items]
Revenues	4,134	6,268	14,082	12,944
China [Member]
Segment Reporting Information [Line Items]
Revenues	11,547	4,151	52,866	24,156
South Korea [Member]
Segment Reporting Information [Line Items]
Revenues	10,977	10,852	44,581	36,099
Singapore [Member]
Segment Reporting Information [Line Items]
Revenues	4,644	4,664	11,985	9,875
Other Asia [Member]
Segment Reporting Information [Line Items]
Revenues	1,102	1,690	3,520	3,249
Germany [Member]
Segment Reporting Information [Line Items]
Revenues	3,527	4,488	8,668	12,357
Other Europe [Member]
Segment Reporting Information [Line Items]
Revenues	$ 2,792	$ 9,841	$ 10,315	$ 20,521

Segment Reporting and Geograp_6

Segment Reporting and Geographic Information - Schedule of Revenue by Major Customers by Reporting Segments (Details)	9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017
Sales [Member] | Customer [Member] | Customer A [Member]
Segment Reporting Information [Line Items]
Entity-wide revenue, major customer, percentage	10.50%	8.20%

Share Repurchase Authorization

Share Repurchase Authorization - Additional Information (Details)	3 Months Ended	9 Months Ended
	Sep. 30, 2018shares	Sep. 30, 2018shares
Share Repurchase Program [Abstract]
Stock Repurchase Program, Number of Shares Authorized to be Repurchased	3,000,000	3,000,000
Number of shares repurchased pursuant to share repurchase authorization	2,000	2,000
Stock Repurchase Program, Remaining Number of Shares Authorized to be Repurchased	709,000	709,000