ExOne (XONE) 10-K 15 Mar 19 2018 FY Annual report Financial data

Document and Entity Information

Document and Entity Information - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2018	Mar. 15, 2019	Jun. 30, 2018
Document And Entity Information [Abstract]
Document Type	10-K
Amendment Flag	false
Document Period End Date	Dec. 31, 2018
Document Fiscal Year Focus	2018
Document Fiscal Period Focus	FY
Trading Symbol	XONE
Entity Registrant Name	ExOne Co
Entity Central Index Key	0001561627
Current Fiscal Year End Date	--12-31
Entity Well-known Seasoned Issuer	No
Entity Current Reporting Status	Yes
Entity Voluntary Filers	No
Entity Filer Category	Accelerated Filer
Entity Small Business	true
Entity Emerging Growth Company	false
Entity Shell Company	false
Entity Common Stock, Shares Outstanding		16,331,202
Entity Public Float			$ 79.4

Statement of Consolidated Opera

Statement of Consolidated Operations and Comprehensive Loss - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017
Income Statement [Abstract]
Revenue	$ 64,644	$ 57,744
Cost of sales	43,703	43,362
Gross profit	20,941	14,382
Operating expenses
Research and development	10,744	9,909
Selling, general and administrative	23,194	24,155
Total operating expenses	33,938	34,064
Loss from operations	(12,997)	(19,682)
Other (income) expense
Interest expense	254	94
Other (income) expense – net	(744)	203
Total other (income) expense	(490)	297
Loss before income taxes	(12,507)	(19,979)
Provision for income taxes	160	38
Net loss	$ (12,667)	$ (20,017)
Net loss per common share:
Basic	$ (0.78)	$ (1.25)
Diluted	$ (0.78)	$ (1.25)
Comprehensive loss:
Net loss	$ (12,667)	$ (20,017)
Other comprehensive (loss) income:
Foreign currency translation adjustments	(1,264)	5,251
Comprehensive loss	$ (13,931)	$ (14,766)

Consolidated Balance Sheet

Consolidated Balance Sheet - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Current assets:
Cash and cash equivalents	$ 7,592	$ 21,848
Restricted cash	1,548	330
Accounts receivable – net	6,695	8,647
Inventories – net	15,930	15,430
Prepaid expenses and other current assets	2,438	1,710
Total current assets	34,203	47,965
Property and equipment – net	41,906	46,797
Intangible assets – net		62
Other noncurrent assets	1,573	736
Total assets	77,682	95,560
Current liabilities:
Current portion of long-term debt	144	137
Accounts payable	4,376	4,291
Accrued expenses and other current liabilities	6,049	6,096
Deferred revenue and customer prepayments	2,343	8,282
Total current liabilities	12,912	18,806
Long-term debt – net of current portion	1,364	1,508
Other noncurrent liabilities	631	37
Total liabilities	14,907	20,351
Contingencies and commitments
Stockholders' equity
Common stock, $0.01 par value, 200,000,000 shares authorized, 16,234,201 (2018) and 16,124,617 (2017) shares issued and outstanding	162	161
Additional paid-in capital	175,214	173,718
Accumulated deficit	(101,853)	(89,186)
Accumulated other comprehensive loss	(10,748)	(9,484)
Total stockholders' equity	62,775	75,209
Total liabilities and stockholders' equity	$ 77,682	$ 95,560

Consolidated Balance Sheet (Par

Consolidated Balance Sheet (Parenthetical) - $ / shares	Dec. 31, 2018	Dec. 31, 2017
Statement Of Financial Position [Abstract]
Common stock, par value	$ 0.01	$ 0.01
Common stock, shares authorized	200,000,000	200,000,000
Common stock, shares issued	16,234,201	16,124,617
Common stock, shares outstanding	16,234,201	16,124,617

Statement of Consolidated Cash

Statement of Consolidated Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017
Operating activities
Net loss	$ (12,667)	$ (20,017)
Adjustments to reconcile net loss to net cash used for operations:
Depreciation and amortization	5,503	6,278
Equity-based compensation	968	2,456
Amortization of debt issuance costs	75	6
Deferred income taxes		1
Provision (recoveries) for bad debts – net	58	(64)
Provision for slow-moving, obsolete and lower of cost or net realizable value inventories – net	1,022	2,056
Gain from disposal of property and equipment – net	(51)	(325)
Changes in assets and liabilities, excluding effects of foreign currency translation adjustments:
Decrease (increase) in accounts receivable	1,637	(1,733)
(Increase) decrease in inventories	(3,441)	357
Increase in prepaid expenses and other assets	(335)	(856)
Increase in accounts payable	195	2,017
Increase in accrued expenses and other liabilities	181	445
Decrease in deferred revenue and customer prepayments	(4,988)	(294)
Net cash used for operating activities	(11,843)	(9,673)
Investing activities
Capital expenditures	(1,327)	(987)
Proceeds from sale of property and equipment	98	3,706
Net cash (used for) provided by investing activities	(1,229)	2,719
Financing activities
Payments on long-term debt	(142)	(137)
Payments on capital leases	(17)	(78)
Proceeds from exercise of employee stock options	529	147
Debt issuance costs	(265)
Net cash provided by (used for) financing activities	105	(68)
Effect of exchange rate changes on cash, cash equivalents, and restricted cash	(71)	1,045
Net change in cash, cash equivalents, and restricted cash	(13,038)	(5,977)
Cash, cash equivalents, and restricted cash at beginning of period	22,178	28,155
Cash, cash equivalents, and restricted cash at end of period	9,140	22,178
Supplemental disclosure of cash flow information
Cash paid for interest	169	87
Cash paid for income taxes	103	5
Supplemental disclosure of noncash investing and financing activities
Transfer of internally developed 3D printing machines from inventories to property and equipment for internal use or leasing activities	2,194	2,868
Transfer of internally developed 3D printing machines from property and equipment to inventories for sale	1,042	3,042
Property and equipment included in assets held for sale	822
Property and equipment included in accounts payable	79	64
Property and equipment included in accrued expenses and other current liabilities		108
Property and equipment acquired through financing arrangements	$ 14	$ 48

Statement of Changes in Consoli

Statement of Changes in Consolidated Stockholders' Equity - USD ($) $ in Thousands	Total	Common Stock [Member]	Additional Paid-in Capital [Member]	Accumulated Deficit [Member]	Accumulated Other Comprehensive Loss [Member]
Beginning Balance at Dec. 31, 2016	$ 87,780	$ 160	$ 171,116	$ (68,761)	$ (14,735)
Beginning Balance, Shares at Dec. 31, 2016		16,017,000
Cumulative-effect adjustment due to the adoption of Financial Accounting Standards Board Accounting Standards Update 2016-16	(408)			(408)
Net loss	(20,017)			(20,017)
Other comprehensive income (loss)	5,251				5,251
Equity-based compensation	2,456	$ 1	2,455
Exercise of employee stock options	$ 147		147
Exercise of employee stock options, shares	18,500	19,000
Common stock issued from equity incentive plan, shares		89,000
Ending Balance at Dec. 31, 2017	$ 75,209	$ 161	173,718	(89,186)	(9,484)
Ending Balance, Shares at Dec. 31, 2017	16,124,617	16,125,000
Net loss	$ (12,667)			(12,667)
Other comprehensive income (loss)	(1,573)				(1,573)
Effect of dissolution of ExOne Italy S.r.l.	309				309
Equity-based compensation	968		968
Exercise of employee stock options	$ 529	$ 1	528
Exercise of employee stock options, shares	67,083	67,000
Common stock issued from equity incentive plan, shares		42,000
Ending Balance at Dec. 31, 2018	$ 62,775	$ 162	$ 175,214	$ (101,853)	$ (10,748)
Ending Balance, Shares at Dec. 31, 2018	16,234,201	16,234,000

Summary of Significant Accounti

Summary of Significant Accounting Policies	12 Months Ended
	Dec. 31, 2018
Accounting Policies [Abstract]
Summary of Significant Accounting Policies	Note 1. Summary of Significant Accounting Policies Organization The ExOne Company (“ExOne”) is a corporation organized under the laws of the state of Delaware. ExOne was formed on January 1, 2013, when The Ex One Company, LLC, a Delaware limited liability company, merged with and into a Delaware corporation, which survived and changed its name to The ExOne Company (the “Reorganization”). As a result of the Reorganization, The Ex One Company, LLC became ExOne, the common and preferred interest holders of The Ex One Company, LLC became holders of common stock and preferred stock, respectively, of ExOne and the subsidiaries of The Ex One Company, LLC became the subsidiaries of ExOne. The consolidated financial statements include the accounts of ExOne and its wholly-owned subsidiaries, ExOne Americas LLC (United States); ExOne GmbH (Germany); ExOne Property GmbH (Germany); ExOne KK (Japan); through December 2018, ExOne Italy S.r.l. (Italy); and through December 2017, ExOne Sweden AB (Sweden). Collectively, the consolidated group is referred to as the “Company”. On December 31, 2017, the Company completed a dissolution of its ExOne Sweden AB (Sweden) subsidiary. The purpose of this dissolution was to further simplify the Company’s legal structure. There were no significant accounting or tax related impacts associated with the dissolution of this subsidiary. On December 28, 2018, the Company completed a dissolution of its ExOne Italy S.r.l. (Italy) subsidiary. The purpose of this dissolution was to further simplify the Company’s legal structure. In connection with the dissolution, the Company settled an intercompany note payable with ExOne Italy S.r.l. pr eviously identified as a long-term investment in the subsidiary. This settlement resulted in the recognition of a $245 foreign exchange loss (recorded as a component of other (income) expense – net in the accompanying statement of consolidated operations and comprehensive loss). The Company filed a registration statement on Form S-3 (No. 333-223690) with the Securities and Exchange Commission (“SEC”) on March 15, 2018. The purpose of the Form S-3 was to register, among other securities, debt securities. Subsidiaries of the Company are co-registrants with the Company (“Subsidiary Guarantors”), and the registration statement registered guarantees of debt securities by one or more of the Subsidiary Guarantors. The Subsidiary Guarantors are 100% owned by the Company and any guarantees by the Subsidiary Guarantors will be full and unconditional . Basis of Presentation The consolidated financial statements of the Company are prepared in conformity with accounting principles generally accepted in the United States of America (“GAAP”). All material intercompany transactions and balances have been eliminated in consolidation. Certain amounts relating to current portion of capital leases ($15) and capital leases – net of current portion ($36) in the accompanying consolidated balance sheet at December 31, 2017, have been reclassified to accrued expenses and other current liabilities and other noncurrent liabilities, respectively, to conform to current period presentation. Use of Estimates The preparation of these consolidated financial statements requires the Company to make certain judgments, estimates and assumptions regarding uncertainties that affect the reported amounts of assets, liabilities, revenue and expenses and related disclosure of contingent assets and liabilities. Areas that require significant judgments, estimates and assumptions include accounting for accounts receivable (including the allowance for doubtful accounts); inventories (including the allowance for slow-moving and obsolete inventories); product warranty reserves; contingencies; income taxes (including the valuation allowance on certain deferred tax assets and liabilities for uncertain tax positions); equity-based compensation (including the valuation of certain equity-based compensation awards issued by the Company); and testing for impairment of long-lived assets (including the identification of asset groups by management, estimates of future cash flows of identified asset groups and fair value estimates used in connection with assessing the valuation of identified asset groups). The Company bases its estimates on historical experience and on various other assumptions that are believed to be reasonable, the results of which form the basis for making judgments about the carrying values of assets and liabilities that are not readily apparent from other sources. Actual results may differ from these estimates. Foreign Currency The local currency is the functional currency for significant operations outside of the United States. The determination of the functional currency of an operation is made based upon the appropriate economic and management indicators. Foreign currency assets and liabilities are translated into their United States dollar equivalents based upon year end exchange rates, and are included in stockholders’ equity as a component of other comprehensive income (loss). Revenues and expenses are translated at average exchange rates. Transaction gains and losses that arise from exchange rate fluctuations are charged to operations as incurred, except for gains and losses associated with certain long-term intercompany transactions between subsidiaries for which settlement is not planned or anticipated in the foreseeable future, which are included in other comprehensive income (loss) in the accompanying statement of consolidated operations and comprehensive loss. The Company transacts business globally and is subject to risks associated with fluctuating foreign exchange rates. Approximately 54.3% Revenue Recognition The Company derives revenue from the sale of 3D printing machines and 3D printed and other products, materials and services. Revenue is recognized by the Company when persuasive evidence of an arrangement exists, delivery has occurred (generally when title and risk and rewards of ownership have transferred to the customer) or services have been rendered, selling price is fixed or determinable and collectability is reasonably assured. The Company enters into arrangements that may provide for multiple deliverables to a customer. Sales of 3D printing machines may also include optional equipment, materials, replacement components and services (installation, training and other services, including maintenance services and/or an extended warranty). The Company identifies all products and services that are to be delivered separately under an arrangement and allocates revenue to each based on their relative fair value. Fair values are generally established based on the prices charged when sold separately by the Company (vendor specific objective evidence). The allocated revenue for each deliverable is then recognized ratably based on relative fair values of the components of the sale. In the absence of vendor specific objective evidence or third party evidence in leading to a relative fair value for a sale component, the Company’s best estimate of selling price is used. The Company also evaluates the impact of undelivered items on the functionality of delivered items for each sales transaction and, where appropriate, defers revenue on delivered items when that functionality has been affected. Functionality is determined to be met if the delivered products or services represent a separate earnings process. The Company’s arrangements for 3D printing machines generally include substantive customer acceptance provisions for which the Company must determine whether it can objectively demonstrate that either company-specific or customer-specific criteria identified in such provisions have been met prior to recognizing revenue on the transaction. Revenue is generally deferred on all such arrangements until formal acceptance is provided from the customer. The Company generally provides customers with a standard twelve month warranty on its 3D printing machines. The standard warranty is not treated as a separate service because the standard warranty is an integral part of the sale of the 3D printing machine. At the time of sale, a liability is recorded (with an offset to cost of sales) based upon the expected cost of replacement parts and labor to be incurred over the life of the standard warranty. Following the standard warranty period, the Company offers its customers optional maintenance service contracts or extended warranties. Deferred maintenance service revenues are generally recognized when the maintenance services are performed since the Company has historical evidence that indicates that the costs of performing the services under the contract are not incurred on a straight-line basis. The Company sells equipment with embedded software to its customers. The embedded software is not sold separately and it is not a significant focus of the Company’s marketing effort. The Company does not provide post-contract customer support specific to the software or incur significant costs that are within the scope of Financial Accounting Standards Board (“FASB”) guidance on accounting for software to be leased or sold. Additionally, the functionality that the software provides is marketed as part of the overall product. The software embedded in the equipment is incidental to the equipment as a whole such that the FASB guidance referenced above is not applicable. Sales of these products are recognized in accordance with FASB guidance on accounting for multiple-element arrangements. Shipping and handling costs billed to customers are included in revenue in the accompanying statement of consolidated operations and comprehensive loss. Costs incurred by the Company associated with shipping and handling are included in cost of sales in the accompanying statement of consolidated operations and comprehensive loss. In assessing collectability as part of the revenue recognition process, the Company considers a number of factors in its evaluation of the creditworthiness of the customer, including past due amounts, past payment history, and current economic conditions. If it is determined that collectability cannot be reasonably assured, the Company will defer recognition of revenue until collectability is assured. For 3D printing machines, the Company’s terms of sale vary by transaction. To reduce credit risk in connection with 3D printing machine sales, the Company may, depending upon the circumstances, require customers to furnish letters of credit or bank guarantees or to provide advanced payment (either partial or in full). Prepayments received from customers are reported as deferred revenue and customer prepayments in the accompanying consolidated balance sheet. For 3D printed and other products and materials, the Company’s terms of sale generally require payment within 30 to 60 days after delivery, although the Company also recognizes that longer payment periods are customary in certain countries where it transacts business. Service arrangements are generally billed in accordance with specific contract terms and are typically billed in advance or in proportion to performance of the related services. The Company has entered into certain contracts for the sale of its products and services with the federal government under fixed-fee, cost reimbursable and time and materials arrangements. With respect to cost reimbursable arrangements with the federal government, the Company generally bills for products and services in accordance with provisional rates as determined by the Company. To the extent that provisional rates billed under these contracts differ from actual experience, a billing adjustment (through revenue) is made in the period in which the difference is identified (generally upon completion of its annual Incurred Cost Submission filing as required by the federal government). For 2018 and 2017, revenues and any adjustments related to these contracts were not significant. Cash and Cash Equivalents The Company considers all highly liquid instruments with maturities when purchased of three months or less to be cash equivalents. The Company’s policy is to invest cash in excess of short-term operating and debt-service requirements in such cash equivalents. These instruments are stated at cost, which approximates fair value because of the short maturity of the instruments. The Company maintains cash balances with financial institutions located in the United States, Germany and Japan. The Company places its cash with high quality financial institutions and believes its risk of loss is limited; however, at times, account balances may exceed international and federally insured limits. The Company has not experienced any losses associated with these cash balances. Accounts Receivable and Net Investment in Sales-Type Leases Accounts receivable and net investment in sales-type leases are reported at their net realizable value. The Company carries its investment in sales-type leases based on discounting the minimum lease payments by the interest rate implicit in the lease and less an allowance for doubtful accounts. write-off and collections experience, current credit conditions, the age of the related balances and economic factors that may affect a customer’s ability to pay. Inventories The Company values all of its inventories at the lower of cost, as determined on the first-in, first-out method or net realizable value. Overhead is allocated to work in process and finished goods based upon normal capacity of the Company’s production facilities. Fixed overhead associated with production facilities that are being operated below normal capacity are recognized as a period expense rather than being capitalized as a product cost. An allowance for slow-moving and obsolete inventories is provided based on historical consumption experience, anticipated product demand and product design changes. These provisions reduce the cost basis of the respective inventories and are recorded as a charge to cost of sales. Property and Equipment Property and equipment are recorded at cost and depreciated on a straight-line basis over the estimated useful lives of the related assets, generally three to forty years. Leasehold improvements are amortized on a straight-line basis over the shorter of their estimated useful lives or the estimated or contractual lives of the related leases. Gains or losses from the sale of assets are recognized upon disposal or retirement of the related assets. Repairs and maintenance are charged to expense as incurred. The Company evaluates long-lived assets held and used for impairment whenever events or changes in circumstances indicate that the carrying amount of such assets (asset group) may not be recoverable. Recoverability of assets is determined by comparing the estimated undiscounted net cash flows of the operations related to the assets (asset group) to their carrying amount. An impairment loss would be recognized when the carrying amount of the assets (asset group) exceeds the estimated undiscounted net cash flows. The amount of the impairment loss to be recorded is calculated as the excess of carrying value of assets (asset group) over their fair value. The determination of what constitutes an asset group, the associated undiscounted net cash flows, the fair value of assets (asset group) and the estimated useful lives of assets require significant judgments and estimates by management. No impairment loss related to held and used assets was recorded by the Company during 2018 or 2017. The Company evaluates long-lived assets held for sale for impairment when the associated long-lived asset (asset group) is first determined to meet the held for sale criteria and in each reporting period thereafter until a disposal is executed or a change in plan occurs. A long-lived asset (asset group) is first determined to meet the held for sale criteria when: management, having the authority to approve the action, commits to a plan to sell the long-lived asset (asset group); the long-lived asset (asset group) is available for immediate sale in its present condition subject only to terms that are usual and customary for sales of such long-lived assets (asset groups); an active program to locate a buyer and other actions required to complete the plan to sell the long-lived asset (asset group) have been initiated; the sale of the long-lived asset (asset group) is probable, and transfer of the long-lived asset (asset group) is expected to qualify for recognition as a completed sale, within one year; the long-lived asset (asset group) is being actively marketed for sale at a price that is reasonable in relation to its current fair value; and actions required to complete the plan indicate that it is unlikely that significant changes to the plan will be made or that the plan will be withdrawn. In connection with the Company’s exit of its Houston, Texas facility (Note 5), the Company reclassified approximately $822 in property and equipment (principally land and building) associated with certain long-lived assets meeting required criteria as held for sale (included in prepaid expenses and other current assets in the accompanying consolidated balance sheet at December 31, 2018). Product Warranty Reserves Substantially all of the Company’s 3D printing machine sales are covered by a standard twelve month warranty. Generally, at the time of sale, a liability is recorded (with an offset to cost of sales) based upon the expected cost of replacement parts and labor to be incurred over the life of the standard warranty. Expected cost is estimated using historical experience for similar products. The Company periodically assesses the adequacy of the product warranty reserves based on changes in these factors and records any necessary adjustments if actual experience indicates that adjustments are necessary. Future claims experience could be materially different from prior results because of the introduction of new, more complex products, a change in the Company’s warranty policy in response to industry trends, competition or other external forces, or manufacturing changes that could impact product quality. In the event that the Company determines that its current or future product repair and replacement costs exceed estimates, an adjustment to these reserves would be charged to cost of sales in the period such a determination is made. Income Taxes The provision for income taxes is determined using the asset and liability approach of accounting for income taxes. Under this approach, the provision for income taxes represents income taxes paid or payable (or received or receivable) for the current year plus the change in deferred taxes during the year. Deferred taxes represent the future tax consequences expected to occur when the reported amounts of assets and liabilities are recovered or paid, and result from differences between the financial and tax bases of assets and liabilities and are adjusted for changes in tax rates and tax laws when enacted. Valuation allowances are established when necessary to reduce deferred tax assets to the amount expected to be realized. The Company’s foreign subsidiaries are taxed as corporations under the taxing regulations of those respective countries. As a result, the accompanying statement of consolidated operations and comprehensive loss includes a provision for income taxes related to these foreign jurisdictions. Any undistributed earnings are intended to be permanently reinvested in the respective subsidiaries. The Company recognizes the income tax benefit from an uncertain tax position only if it is more likely than not that the income tax position will be sustained on examination by the taxing authorities based upon the technical merits of the position. The income tax benefits recognized in the consolidated financial statements from such positions are then measured based upon the largest amount that has a greater than 50% likelihood of being realized upon settlement. Income tax benefits that do not meet the more likely than not criteria are recognized when effectively settled, which generally means that the statute of limitations has expired or that the appropriate taxing authority has completed its examination even though the statute of limitations remains open. Interest and penalties related to uncertain tax positions are recognized as part of the provision for income taxes and are accrued beginning in the period that such interest and penalties would be applicable under relevant tax law until such time that the related income tax benefits are recognized. Taxes on Revenue Producing Transactions Taxes assessed by governmental authorities on revenue producing transactions, including sales, excise, value added and use taxes, are recorded on a net basis (excluded from revenue) in the accompanying statement of consolidated operations and comprehensive loss. Research and Development The Company is involved in research and development of new methods and technologies relating to its products. Research and development expenses are charged to operations as they are incurred. The Company capitalizes the cost of certain materials, equipment and facilities that have alternative future uses in research and development projects or otherwise. Advertising Advertising costs are charged to expense as incurred, and were not significant for 2018 or 2017. Defined Contribution Plan The Company sponsors a defined contribution savings plan under section 401(k) of the Internal Revenue Code. Under the plan, participating employees in the United States may elect to defer a portion of their pre-tax earnings, up to the Internal Revenue Service’s annual contribution limit. During 2018 and 2017 the Company made discretionary matching contributions of 50% of the first 8% of employee contributions, subject to certain Internal Revenue Service limitations. Discretionary matching contributions made by the Company during 2018 and 2017 were approximately $320 and $303, respectively. Equity-Based Compensation The Company recognizes compensation expense for equity-based grants using the straight-line attribution method in which the expense is recognized ratably over the requisite service period based on the grant date fair value of the related award. Forfeitures of pre-vesting equity-based grants are recognized as they are incurred and result in an offset to equity-based compensation expense in the period of recognition. Fair value of equity-based awards is estimated on the date of grant using the Black-Scholes option pricing model. Recently Adopted Accounting Guidance On January 1, 2018, the Company adopted 2017-09, “Compensation – Stock Compensation: Scope of Modification Accounting.” This ASU requires registrants to apply modification accounting unless three specific criteria are met. The three criteria are: the fair value of the award is the same before and after the modification, the vesting conditions are the same before and after the modification and the classification as a debt or equity award is the same before and after the modification. Management has determined that the adoption of this ASU did not have an impact on the consolidated financial statements of the Company. On January 1, 2017, the Company adopted FASB ASU 2016-16, “Income Taxes: Intra-Entity Transfers of Assets Other Than Inventory.” This ASU modifies existing guidance and is intended to reduce diversity in practice with respect to the accounting for the income tax consequences of intra-entity transfers of assets. The ASU indicates that the former exception to income tax accounting that requires companies to defer the income tax effects of certain intercompany transactions would apply only to intercompany inventory transactions. That is, the exception no longer applies to intercompany sales and transfers of other assets ( e.g. e.g. Recently Issued Accounting Guidance The Company considers the applicability and impact of all ASUs issued by the FASB. Recently issued ASUs not listed below either were assessed and determined to be not applicable or are currently expected to have no impact on the consolidated financial statements of the Company. In August 2016, the FASB issued ASU 2016-15, “Statement of Cash Flows: Classification of Certain Cash Receipts and Cash Payments.” This ASU is intended to reduce diversity in practice in how certain cash receipts and payments are presented and classified in the statement of cash flows. The standard provides guidance in a number of situations including, among others, settlement of zero-coupon bonds, contingent consideration payments made after a business combination, proceeds from the settlement of insurance claims, and distributions received from equity method investees. The ASU also provides guidance for classifying cash receipts and payments that have aspects of more than one class of cash flows. This guidance became effective for the Company on January 1, 2019. Management has determined that the adoption of this ASU will not have an effect on the consolidated financial statements of the Company. In June 2016, the FASB issued ASU 2016-13, “Financial Instruments – Credit Losses.” This ASU added a new impairment model (known as the current expected credit loss (“CECL”) model) that is based on expected losses rather than incurred losses. Under the new guidance, an entity recognizes as an allowance its estimate of expected credit losses. The CECL model applies to most debt instruments, trade receivables, lease receivables, financial guarantee contracts, and other loan commitments. The CECL model does not have a minimum threshold for recognition of impairment losses and entities will need to measure expected credit losses on assets that have a low risk of loss. These changes become effective for the Company on January 1, 2020. Management is currently evaluating the potential impact of these changes on the consolidated financial statements of the Company. In February 2016, the FASB issued ASU 2016-02, “Leases.” This ASU requires lessees to recognize a right-of-use asset and lease liability on the consolidated balance sheet for leases classified as operating leases. For leases with a term of 12 months or less, a lessee is permitted to make an accounting policy election by class of underlying asset not to recognize a right-of-use asset and lease liability. Additionally, when measuring assets and liabilities arising from a lease, optional payments should be included only if the lessee is reasonably certain to exercise an option to extend the lease, exercise a purchase option, or not exercise an option to terminate the lease. A right-of-use asset represents an entity’s right to use the underlying asset for the lease term, and a lease liability represents an entity’s obligation to make lease payments. Currently, an asset and liability only are recorded for leases classified as capital leases (financing leases). The measurement, recognition, and presentation of expenses and cash flows arising from leases by a lessee remains the same. This guidance became effective for the Company on January 1, 2019. In connection with the adoption of this guidance, the Company has completed an assessment resulting in an accumulation of all of its leasing arrangements and has validated the information for accuracy and completeness. Upon adoption of the new lease guidance, management expects to record a right-of-use asset and lease liability, each in the amount of approximately $400, on the Company’s consolidated balance sheet for various types of operating leases, including certain machinery and other equipment and vehicles. This amount is equivalent to the aggregate future minimum lease payments on a discounted basis. The Company has also elected to apply the package of transitional practical expedients of the new lease guidance by allowing the Company to not: (1) reassess if expired or existing contracts are, or contain, leases; (2) reassess lease classification for any expired or existing leases; and (3) reassess initial direct costs for any existing leases. Additionally, in July 2018, the FASB issued guidance to provide for an alternative transition method to the new lease guidance, whereby an entity can choose to not reflect the impact of the new lease guidance in the prior periods included in its consolidated financial statements. The Company plans to utilize this alternative transition method in connection with its adoption on January 1, 2019. In May 2014, the FASB issued ASU 2014-09, “Revenue from Contracts with Customers.” This ASU created a comprehensive framework for all entities in all industries to apply in the determination of when to recognize revenue and, therefore, supersedes virtually all existing revenue recognition requirements and guidance. This framework is expected to provide a consistent and comparable methodology for revenue recognition. The core principle of the guidance is that an entity should recognize revenue 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. To achieve this principle, an entity should apply the following steps: identify the contract(s) with a customer, identify the performance obligations in the contract(s), determine the transaction price, allocate the transaction price to the performance obligations in the contract(s), and recognize revenue when, or as, the entity satisfies a performance obligation. In August 2015, the FASB issued ASU 2015-14, “Revenue from Contracts with Customers: Deferral of the Effective Date,” which deferred the effective date of this guidance for the Company until January 1, 2019. The Company adopted this guidance on January 1, 2019, using the modified retrospective approach. Revenue from the Company’s sale of 3D printing machines and 3D printed and other products, materials and services continues to generally be recognized when the related machines, products or materials are delivered or accepted by the Company’s customers or as the related services are performed by the Company. As such, the adoption of this guidance did not have a material impact on the Company’s financial position or results of operations. The Company expects to include the enhanced disclosures required by this guidance in its consolidated financial statements for the three months ended March 31, 2019.

Liquidity

Liquidity	12 Months Ended
	Dec. 31, 2018
Organization Consolidation And Presentation Of Financial Statements [Abstract]
Liquidity	Note 2. Liquidity The Company has incurred a net loss in each of its annual periods since its inception. As shown in the accompanying statement of consolidated operations and comprehensive loss, the Company incurred a net loss of approximately $12,667 and $20,017 for 2018 and 2017, respectively. At December 31, 2018, the Company had approximately $7,592 in unrestricted cash and cash equivalents. Since its inception, the Company has received cumulative unrestricted net proceeds from the sale of its common stock (through its initial public offering and subsequent secondary offerings) of approximately $168,361 to fund its operations. Most recently, the Company received approximately $595 in unrestricted net proceeds from the sale of its common stock during the three months ended March 31, 2016 through an At Market Issuance Sales Agreement (“ATM”) with FBR Capital Markets & Co. (“FBR”) and MLV & Co. LLC (“MLV”) pursuant to which FBR and MLV agreed to act as distribution agents in the sale of up to $50,000 in the aggregate of ExOne common stock in “at the market offerings” as defined in Rule 415 under the Securities Act of 1933, as amended (the “Securities Act”) In March 2018 the Company entered into a three-year, $15,000 revolving credit facility with a related party (Note 14) to provide additional funding for working capital and general corporate purposes. In June 2018 the Company initiated a 2018 global cost realignment program focused on a reduction in the Company’s production overhead costs and operating expenses in an effort to drive efficiency in its operations and preserve capital. Management believes that the Company’s existing capital resources will be sufficient to support the Company’s operating plan. If management anticipates that the Company’s actual results will differ from its operating plan, management believes it has sufficient capabilities to enact cost savings measures to preserve capital (in addition to the costs savings measures associated with the Company’s 2018 global cost realignment program further described above). The Company may also seek to raise additional capital to support its growth through additional debt, equity or other alternatives (including asset sales) or a combination thereof.

Accumulated Other Comprehensive

Accumulated Other Comprehensive Loss	12 Months Ended
	Dec. 31, 2018
Equity [Abstract]
Accumulated Other Comprehensive Loss	Note 3. Accumulated Other Comprehensive Loss The following table summarizes changes in the components of accumulated other comprehensive loss: For the years ended December 31, 2018 2017 Foreign currency translation adjustments Balance at beginning of period $ (9,484 ) $ (14,735 ) Other comprehensive (loss) income before reclassifications (1,573 ) 5,251 Amounts reclassified from accumlated other comprehensive loss 309 — Balance at end of period $ (10,748 ) $ (9,484 ) Foreign currency translation adjustments consist of the effect of translation of functional currency financial statements (denominated in the euro and Japanese yen) to the reporting currency of the Company (United States dollar) and certain long-term intercompany transactions between subsidiaries for which settlement is not planned or anticipated in the foreseeable future. For 2018, foreign currency translation adjustments also included approximately $245 in a foreign exchange loss recognized in connection with the settlement of an intercompany note payable with ExOne Italy S.r.l. pr eviously identified as a long-term investment in the subsidiary (Note 1) and approximately $64 associated with the dissolution of the related subsidiary (both amounts recognized in other (income) expense – net in the accompanying statement of consolidated operations and comprehensive loss). There were no tax impacts associated with such reclassifications. Other than the amounts identified above, no amounts were reclassified to earnings for any of the periods presented.

Loss Per Share

Loss Per Share	12 Months Ended
	Dec. 31, 2018
Earnings Per Share [Abstract]
Loss Per Share	Note 4. Loss Per Share The Company presents basic and diluted loss per common share amounts. Basic loss per common share is calculated by dividing net loss available to common stockholders by the weighted average number of common shares outstanding during the applicable period. Diluted loss per share is calculated by dividing net loss available to common stockholders by the weighted average number of common shares and common equivalent shares outstanding during the applicable period. As the Company incurred a net loss during 2018 and 2017, basic average common shares outstanding and diluted average common shares outstanding were the same because the effect of potential shares of common stock, including stock options (621,986 — 2018 and 674,470 — 2017) and unvested restricted stock issued (67,001 — 2018 and 52,502 — 2017), was anti-dilutive. The information used to compute basic and diluted net loss per common share was as follows: For the years ended December 31, 2018 2017 Net loss $ (12,667 ) $ (20,017 ) Weighted average shares outstanding (basic and diluted) 16,176,415 16,062,424 Net loss per common share: Basic $ (0.78 ) $ (1.25 ) Diluted $ (0.78 ) $ (1.25 )

Restructuring

Restructuring	12 Months Ended
	Dec. 31, 2018
Restructuring And Related Activities [Abstract]
Restructuring	Note 5. Restructuring Houston, Texas In August 2018 the Company committed to a plan to consolidate certain of its three-dimensional (“3D”) printing operations from its Houston, Texas facility into its Troy, Michigan facility. These actions were taken as part of the Company’s efforts to optimize its business model and maximize its facility utilization. During 2018, the Company recorded a charge of approximately $28 split between cost of sales ($15) and selling, general and administrative expense ($13) associated with involuntary employee terminations related to this plan. During 2018, the Company recorded an additional charge of approximately $1 (to cost of sales) associated with asset impairments related to this plan. There are no additional charges expected to be incurred associated with this plan in future periods. The Company settled all amounts associated with involuntary employee terminations during 2018. Desenzano del Garda, Italy In December 2017 the Company committed to a plan to consolidate certain of its 3D printing operations from its Desenzano del Garda, Italy facility into its Gersthofen, Germany facility. These actions were taken as part of the Company’s efforts to optimize its business model and maximize its facility utilization. During 2017, the Company recorded a charge of approximately $72 split between cost of sales ($19) and selling, general and administrative expense ($53) associated with involuntary employee terminations related to this plan. During 2018, the Company recorded additional charges of approximately $258 associated with other exit costs ($17) and asset impairments ($241) related to this plan. In addition, during 2018, the Company recorded a gain from disposal of certain property and equipment of approximately $51 (recorded to cost of sales in the accompanying statement of consolidated operations and comprehensive loss). Charges associated with other exit costs recorded during 2018 were recorded to cost of sales in the accompanying statement of consolidated operations and comprehensive loss. Charges associated with asset impairments recorded during 2018 were recorded to cost of sales as a component of depreciation expense in the accompanying statement of consolidated operations and comprehensive loss. Other exit costs relate to the remaining facility rent due under a non-cancellable operating lease following the cessation of operations at the facility in January 2018. Asset impairment charges relate to certain leasehold improvements associated with the exited facility and other equipment which was abandoned by the Company. There are no additional charges expected to be incurred associated with this plan in future periods. The Company settled all amounts associated with involuntary employee terminations and facility rentals during 2018. North Las Vegas, Nevada and Chesterfield, Michigan In January 2017, the Company committed to a plan to consolidate certain of its 3D printing operations from its North Las Vegas, Nevada facility into its Troy, Michigan and Houston, Texas facilities and exit its non-core specialty machining operations in its Chesterfield, Michigan facility. These actions were taken as a result of t he accelerating adoption rate of the Company’s sand printing technology in North America which has resulted in a refocus of the Company’s operational strategy. As a result of these actions, during 2017, the Company recorded charges of approximately $1,016, including approximately $142 associated with involuntary employee terminations, approximately $7 associated with other exit costs and approximately $867 associated with asset impairments. Charges associated with involuntary employee terminations and other exit costs were recorded to cost of sales in the accompanying statement of consolidated operations and comprehensive loss. Charges associated with asset impairments were split between cost of sales ($598), as a component of depreciation expense, and selling, general and administrative expenses ($269), as a component of amortization expense, in the accompanying statement of consolidated operations and comprehensive loss. There are no additional charges expected to be incurred associated with this plan in future periods. Charges associated with asset impairments relate principally to the Company’s plan to exit its non-core specialty machining operations in its Chesterfield, Michigan facility. On April 21, 2017, the Company sold to a third party certain assets associated with these operations including inventories (approximately $79), property and equipment (approximately $2,475) and other contractual rights (approximately $269). Total gross proceeds from the sale of these assets were approximately $2,050. After deducting costs directly attributable to the sale of these assets (approximately $128), the Company recorded an impairment loss during the three months ended March 31, 2017, of approximately $859 split between property and equipment ($590) and intangible assets ($269) based on the excess of the carrying value over the estimated fair value of the related assets at March 31, 2017 (recorded to cost of sales in the accompanying statement of consolidated operations and comprehensive loss), and a loss on disposal during the three months ended June 30, 2017, of approximately $42 (recorded to cost of sales in the accompanying statement of consolidated operations and comprehensive loss). Separate from the transaction described above, on May 9, 2017, the Company sold to a third party certain property and equipment (principally land and building) associated with its North Las Vegas, Nevada facility. Total gross proceeds from the sale of these assets were approximately $1,950. After deducting costs directly attributable to the sale of these assets (approximately $137), the Company recorded a gain on disposal (recorded to cost of sales in the accompanying statement of consolidated operations and comprehensive loss), of approximately $347. Additionally, the Company recorded an impairment loss during 2017 of approximately $8 associated with certain property and equipment which was abandoned in connection with the Company’s exit of its North Las Vegas, Nevada facility.

Impairment

Impairment	12 Months Ended
	Dec. 31, 2018
Asset Impairment Charges [Abstract]
Impairment	Note 6. Impairment During the three months ended December 31, 2018, as a result of continued operating losses and cash flow deficiencies, the Company identified a triggering event requiring a test for the recoverability of long-lived assets held and used at the asset group level. Assessing the recoverability of long-lived assets held and used requires significant judgments and estimates by management. For purposes of testing long-lived assets for recoverability, the Company operates as three separate asset groups: United States, Europe and Japan. In assessing the recoverability of long-lived assets held and used, the Company determined the carrying amount of long-lived assets held and used to be in excess of the estimated future undiscounted net cash flows of the related assets. The Company proceeded to determine the fair value of its long-lived assets held and used, principally through use of the market approach. The Company’s use of the market approach included consideration of market transactions for comparable assets. Management concluded that the fair value of long-lived assets held and used exceeded their carrying value and, as such, no impairment loss was recorded . A significant decrease in the market price of a long-lived asset, adverse change in the use or condition of a long-lived asset, adverse change in the business climate or legal or regulatory factors impacting a long-lived asset and continued operating losses and cash flow deficiencies associated with a long-lived asset, among other indicators, could cause a future assessment to be performed which may result in an impairment of long-lived assets held and used, resulting in a material adverse effect on the financial position and results of operations of the Company.

Cash, Cash Equivalents, and Res

Cash, Cash Equivalents, and Restricted Cash	12 Months Ended
	Dec. 31, 2018
Cash And Cash Equivalents [Abstract]
Cash, Cash Equivalents, and Restricted Cash	Note 7. Cash, Cash Equivalents, and Restricted Cash The following provides a reconciliation of cash, cash equivalents, and restricted cash as reported in the accompanying consolidated balance sheet to the same such amounts shown in the accompanying statement of consolidated cash flows at December 31: 2018 2017 Cash and cash equivalents $ 7,592 $ 21,848 Restricted cash 1,548 330 Total cash, cash equivalents, and restricted cash shown in the statement of consolidated cash flows $ 9,140 $ 22,178 Restricted cash at December 31, 2018 includes approximately $1,044 associated with cash collateral required by a German bank for short-term financial guarantees issued by ExOne GmbH in connection with certain commercial transactions requiring security (Note 13). Restricted cash at December 31, 2018 and 2017 includes approximately $504 and $330, respectively, associated with cash collateral required by a United States bank to offset certain short-term, unsecured lending commitments associated with the Company’s corporate credit card program. Each of the balances described are considered legally restricted by the Company .

Inventories

Inventories	12 Months Ended
	Dec. 31, 2018
Inventory Disclosure [Abstract]
Inventories	Note 8. Inventories Inventories consisted of the following at December 31: 2018 2017 Raw materials and components $ 7,747 $ 7,171 Work in process 5,147 4,630 Finished goods 3,036 3,629 $ 15,930 $ 15,430 Raw materials and components consist of consumable materials and component parts and subassemblies associated with 3D printing machine manufacturing and support activities. Work in process consists of 3D printing machines and other products in varying stages of completion. Finished goods consist of 3D printing machines and other products prepared for sale in accordance with customer specifications. At December 31, 2018 and 2017, the allowance for slow-moving and obsolete inventories was approximately $4,143 During the three months ended June 30, 2018, the Company recorded a charge of approximately $561 to cost of sales in the accompanying statement of consolidated operations and comprehensive loss attributable to certain industrial microwave inventories based on a sustained absence of demand for such curing solutions and a decision by the Company to discontinue future manufacturing of such industrial microwaves. During the three months ended June 30, 2017, the Company recorded a charge of approximately $1,460 to cost of sales in the accompanying statement of consolidated operations and comprehensive loss attributable to certain raw material and component inventories (principally machine frames and other fabricated components) associated with the Company’s Exerial 3D printing machine platform based on decisions made by the Company during the period related to certain design changes to the underlying platform (rendering certain elements of the previous design obsolete). During 2018 and 2017, the Company recorded net charges of approximately $29 and $271, respectively, to cost of sales in the accompanying statement of consolidated operations and comprehensive loss associated with certain raw materials and components and work in process inventories for which cost was determined to exceed net realizable value.

Long-Lived Assets

Long-Lived Assets	12 Months Ended
	Dec. 31, 2018
Long Lived Assets [Abstract]
Long-Lived Assets	Note 9. Long-Lived Assets Property and Equipment Property and equipment consisted of the following at December 31: 2018 2017 Economic Life (in years) Land $ 7,024 $ 7,205 N/A Buildings and related improvements 25,895 27,785 5 - 40 Machinery and equipment 20,667 22,034 3 - 20 Other 7,121 6,772 3 - 20 60,707 63,796 Less: Accumulated depreciation (19,306 ) (17,739 ) 41,401 46,057 Construction-in-progress 505 740 Property and equipment - net $ 41,906 $ 46,797 Machinery and equipment includes assets leased by the Company of approximately $101 Machinery and equipment includes assets leased to customers (principally 3D printing machines and related equipment) under operating lease arrangements of approximately $2,345 and $2,254 at December 31, 2018 and 2017, respectively. The carrying value of these assets was approximately $1,264 Minimum future rentals of machinery and equipment under non-cancellable arrangements at December 31, 2018, were as follows: 2019 $ 687 2020 148 2021 48 2022 — 2023 — Thereafter — $ 883 Depreciation expense was approximately $5,439 and $5,637 for 2018 and 2017, respectively. Depreciation expense for 2017 includes approximately $598 in accelerated depreciation (impairment) associated with the Company’s consolidation of its 3D printing operations from its North Las Vegas, Nevada facility into its Troy, Michigan and Houston, Texas facilities and exit of its specialty machining operations in Chesterfield, Michigan (Note 5). Intangible Assets Intangible assets consisted of the following at December 31: 2018 Gross Amount Accumulated Amortization Net Unpatented technology $ 1,388 $ (1,388 ) $ — Trade names 30 (30 ) — $ 1,418 $ (1,418 ) $ — 2017 Gross Amount Accumulated Amortization Net Unpatented technology $ 1,453 $ (1,392 ) $ 61 Trade names 31 (30 ) 1 $ 1,484 $ (1,422 ) $ 62 Amortization expense related to the intangible assets was approximately $64 and $641 for 2018 and 2017, respectively. Amortization expense related to the intangible assets for 2017 includes approximately $269 in accelerated amortization (impairment) associated with the Company’s exit of its specialty machining operations in Chesterfield, Michigan (Note 5).

Net Investment in Sales-Type Le

Net Investment in Sales-Type Leases	12 Months Ended
	Dec. 31, 2018
Leases [Abstract]
Net Investment in Sales-Type Leases	Note 10. Net Investment in Sales-Type Leases The Company’s net investment in sales-type leases consisted of the following at December 31: 2018 2017 Future minimum lease payments receivable $ 1,969 $ 1,100 Less: Unearned interest income (316 ) (159 ) Net investment in sales-type leases $ 1,653 $ 941 At December 31, 2018, the Company’s net investment in sales-type leases was included in accounts receivable ($302) and other noncurrent assets ($1,351) in the accompanying consolidated balance sheet. At December 31, 2017, the Company’s net investment in sales-type leases was included in accounts receivable ($205) and other noncurrent assets ($736) in the accompanying consolidated balance sheet. Future minimum lease payments due from customers under sales-type leases as of December 31, 2018 were as follows: 2019 $ 409 2020 382 2021 382 2022 382 2023 414 Thereafter — $ 1,969 During 2018 and 2017, interest income associated with sales-type leases (recorded to revenue in the accompanying statement of consolidated operations and comprehensive loss) was approximately $48 and $28, respectively.

Accrued Expenses and Other Curr

Accrued Expenses and Other Current Liabilities	12 Months Ended
	Dec. 31, 2018
Payables And Accruals [Abstract]
Accrued Expenses and Other Current Liabilities	Note 11. Accrued Expenses and Other Current Liabilities Accrued expenses and other current liabilities consisted of the following at December 31: 2018 2017 Accrued payroll and related costs $ 1,895 $ 2,044 Product warranty reserves 1,670 1,300 Liability for uncertain tax positions 820 858 Accrued license fees 721 397 Accrued professional fees 215 223 Value-added taxes payable 140 28 Accrued sales commissions 123 307 Accrued property taxes 108 99 Income taxes payable 90 32 Other 267 808 $ 6,049 $ 6,096

Product Warranty Reserves

Product Warranty Reserves	12 Months Ended
	Dec. 31, 2018
Product Warranties Disclosures [Abstract]
Product Warranty Reserves	Note 12. Product Warranty Reserves The following table summarizes changes in product warranty reserves (such amounts reflected in accrued expenses and other current liabilities in the accompanying consolidated balance sheet): For the years ended December 31, 2018 2017 Balance at beginning of period $ 1,300 $ 1,115 Provisions for new issuances 1,803 1,288 Payments (960 ) (701 ) Reserve adjustments (434 ) (500 ) Foreign currency translation adjustments (39 ) 98 Balance at end of period $ 1,670 $ 1,300

Contingencies and Commitments

Contingencies and Commitments	12 Months Ended
	Dec. 31, 2018
Commitments And Contingencies Disclosure [Abstract]
Contingencies and Commitments	Note 13. Contingencies and Commitments Contingencies On March 1, 2018, the Company’s ExOne GmbH subsidiary notified Voxeljet AG that it has materially breached a 2003 Patent and Know-How Transfer Agreement and asserted its rights to set-off damages as a result of the breaches against the annual license fee due by the Company under the agreement. At this time, the Company cannot reasonably estimate a contingency, if any, related to this matter. On July 1, 2017, the Company (through its ExOne GmbH subsidiary) entered into a Settlement Agreement with Kocel Foundry Limited (also known as Kocel CSR Casting Company, Limited) and Kocel Group (Hong Kong) Limited (collectively, “Kocel”) relating to settlement of the arbitration case (no. 100019-2017) administered by the Swiss Chambers’ Arbitration Institution Notice of Arbitration, as filed by the Company on January 25, 2017. Among other things, the Settlement Agreement provided for a cash payment from ExOne GmbH to Kocel of approximately $811 and a settlement and release of claims related to a sales agreement between the parties for certain 3D printing machines and related equipment (the “Sales Agreement”). Based on the terms of the Settlement Agreement, including the final acceptance by Kocel of the 3D printing machines and related equipment, and relief from further obligation, liability or warranty for both parties (excluding certain intellectual property considerations), the Company recorded revenue of approximately $2,762 associated with the Sales Agreement (net of the cash payment made by ExOne GmbH to Kocel, such payment made on July 5, 2017) and the related cost of sales, during the three months ended September 30, 2017. The Company is subject to various litigation, claims, and proceedings which have been or may be instituted or asserted from time to time in the ordinary course of business. Management does not believe that the outcome of any pending or threatened matters will have a material adverse effect, individually or in the aggregate, on the financial position, results of operations or cash flows of the Company . Financial Guarantees and Letters of Credit In the normal course of its operations, ExOne GmbH issues financial guarantees and letters of credit to third parties in connection with certain commercial transactions requiring security. ExOne GmbH maintains a credit facility agreement with a German bank which provides for various short-term financings in the form of overdraft credit, financial guarantees, letters of credit and collateral security for commercial transactions for approximately $1,400 (€1,300). In addition, ExOne GmbH may use the credit facility agreement for short-term, fixed-rate loans in minimum increments of approximately $100 (€100) with minimum terms of at least thirty days. The overdraft credit interest rate is fixed at 10.2% while the interest rate associated with commercial transactions requiring security (financial guarantees, letters of credit or collateral security) is fixed at 1.75%. The credit facility agreement has an indefinite term and is subject to cancellation by either party at any time upon repayment of amounts outstanding or expiration of commercial transactions requiring security. There is no commitment fee associated with the credit facility agreement. There are no negative covenants associated with the credit facility agreement. The credit facility agreement has been guaranteed by the Company. At December 31, 2018 and 2017, there were no outstanding borrowings in the form of overdraft credit or short-term loans under the credit facility agreement. At December 31, 2018, total outstanding financial guarantees and letters of credit issued by ExOne GmbH under the credit facility agreement were approximately $1,044 (€912) with expiration dates ranging from March 2019 through November 2019. At December 31, 2017, total outstanding guarantees and letters of credit issued by ExOne GmbH under the credit facility agreement were approximately $1,128 (€941). In addition to amounts issued by ExOne GmbH under the credit facility agreement, during 2017, ExOne GmbH entered into a separate agreement with the same German bank for additional capacity for a financial guarantee associated with a commercial transaction requiring security. Terms of the separate agreement were substantially similar to those of the existing credit security agreement except that the requirement for cash collateral was waived by the German bank as it also represents the counterparty in the related transaction. At December 31, 2017, the outstanding financial guarantee issued by ExOne GmbH under this separate agreement was approximately $96 (€80) with an expiration date of June 2022. Leases The Company leases machinery and other equipment and vehicles under operating lease arrangements (with initial terms greater than twelve months), expiring in various years through 2026. Future minimum lease payments of operating lease arrangements (with initial terms greater than twelve months) at December 31, 2018, were approximately as follows: 2019 $ 170 2020 111 2021 76 2022 67 2023 12 Thereafter 5 $ 441 Rent expense under operating lease arrangements was approximately $235 and $358 for 2018 and 2017, respectively.

Related Party Revolving Credit

Related Party Revolving Credit Facility	12 Months Ended
	Dec. 31, 2018
Related Party Transactions [Abstract]
Related Party Revolving Credit Facility	Note 14. Related Party Revolving Credit Facility On March 12, 2018, ExOne and its ExOne Americas LLC and ExOne GmbH subsidiaries, as guarantors (collectively, the “Loan Parties”), entered into a Credit Agreement and related ancillary agreements with LBM Holdings, LLC (“LBM”), a company controlled by S. Kent Rockwell, who was the Executive Chairman of the Company (a related party) at such date and effective June 20, 2018, became the Chairman and Chief Executive Officer of the Company, relating to a $15,000 revolving credit facility (the “LBM Credit Agreement”) to provide additional funding for working capital and general corporate purposes. The LBM Credit Agreement provides for a term of three years (through March 12, 2021) and bears interest at a rate of one month LIBOR plus an applicable margin of 500 basis points (approximately 6.7% and 7.5% at inception and December 31, 2018, respectively). The LBM Credit Agreement requires a commitment fee of 75 basis points, or 0.75%, on the unused portion of the facility, payable monthly in arrears. In addition, an up-front commitment fee of 125 basis points, or 1.25% (approximately $188), was required at closing. Borrowings under the LBM Credit Agreement are required to be in minimum increments of $1,000. ExOne may terminate or reduce the credit commitment at any time during the term of the LBM Credit Agreement without penalty. ExOne may also make prepayments against outstanding borrowings under the LBM Credit Agreement at any time without penalty. Borrowings under the LBM Credit Agreement have been collateralized by the accounts receivable, inventories and machinery and equipment of the Loan Parties. At inception of the credit facility and December 31, 2018, the total estimated value of collateral was in significant excess of the maximum borrowing capacity under the LBM Credit Agreement. The LBM Credit Agreement contains several affirmative covenants including prompt payment of liabilities and taxes; maintenance of insurance, properties, and licenses; and compliance with laws. The LBM Credit Agreement also contains several negative covenants including restricting the incurrence of certain additional debt; prohibiting future liens (other than permitted liens); prohibiting investment in third parties; limiting the ability to pay dividends; limiting mergers, acquisitions, and dispositions; and limiting the sale of certain property and equipment of the Loan Parties. The LBM Credit Agreement does not contain any financial covenants. The LBM Credit Agreement also contains events of default, including, but not limited to, cross-default to certain other debt, breaches of representations and warranties, change of control events and breaches of covenants. LBM was determined to be a related party based on common control by S. Kent Rockwell, who was the Executive Chairman of the Company at the time the Company entered into the LBM Credit Agreement and effective June 20, 2018, became the Chairman and Chief Executive Officer of the Company. Accordingly, the Company does not consider the LBM Credit Agreement indicative of a fair market value lending. Prior to execution, the LBM Credit Agreement was subject to review and approval by the Audit Committee of the Board of Directors (the “Board”) and by a sub-committee of independent members of the ExOne Board. At the time of execution of the LBM Credit Agreement, the $15,000 in available loan proceeds were deposited into an escrow account with an unrelated, third party financial institution acting as escrow agent pursuant to a separate Escrow Agreement by and among the parties. Loan proceeds held in escrow are available to the Company upon its submission to the escrow agent of a loan request. Such proceeds will not be available to LBM until payment in-full of the obligations under the LBM Credit Agreement and termination of the LBM Credit Agreement. Payments of principal and other obligations will be made to the escrow agent, while interest payments will be made directly to LBM. Provided there exists no potential default or event of default, the LBM Credit Agreement and Escrow Agreement prohibit any acceleration of repayment of any amount outstanding under the LBM Credit Agreement and prohibit termination of the LBM Credit Agreement or withdrawal from escrow of any unused portion of the LBM Credit Agreement. There were no borrowings by the Company under the LBM Credit Agreement from March 12, 2018 (inception) through December 31, 2018. The Company incurred approximately $265 in debt issuance costs associated with the LBM Credit Agreement (including the aforementioned up front commitment fee paid at closing to LBM). During 2018, the Company recorded interest expense relating to the LBM Credit Agreement of approximately $160. Included in interest expense for 2018 was approximately $70 associated with amortization of debt issuance costs (resulting in approximately $195 in remaining debt issuance costs at December 31, 2018, of which $88 was included in prepaid expenses and other current assets and $107 was included in other noncurrent assets in the accompanying consolidated balance sheet). Included in interest expense for 2018 was approximately $90 associated with the commitment fee on the unused portion of the revolving credit facility, of which at December 31, 2018 approximately $10 was included in accounts payable in the accompanying consolidated balance sheet. Amounts payable to LBM at December 31, 2018 were settled by the Company in January 2019.

Long-Term Debt

Long-Term Debt	12 Months Ended
	Dec. 31, 2018
Debt Disclosure [Abstract]
Long-Term Debt	Note 15. Long-Term Debt Long-term debt consisted of the following at December 31: 2018 2017 Principal Unamortized Debt Issuance Costs Net Principal Unamortized Debt Issuance Costs Net Building note payable $ 1,533 $ (25 ) $ 1,508 $ 1,675 $ (30 ) $ 1,645 Less: Amount due within one year (149 ) 5 (144 ) (142 ) 5 (137 ) $ 1,384 $ (20 ) $ 1,364 $ 1,533 $ (25 ) $ 1,508 Terms of the building note payable include monthly payments of approximately $18 including interest at 4.00% through May 2017, and subsequently, monthly payments of approximately $19 including interest at the monthly average yield on United States Treasury Securities plus 3.25% for the remainder of the term through May 2027. The building note payable is collateralized by the Company’s facility located in North Huntingdon, Pennsylvania which had a carrying value of approximately $5,128 at December 31, 2018. At December 31, 2018, the Company identified that it was not in compliance with the annual cash flow-to-debt service ratio covenant associated with the building note payable. The Company requested and was granted a waiver related to compliance with this annual covenant at December 31, 2018 and through December 31, 2019. Related to the 2018 non-compliance, there were no cross default provisions or related impacts on other lending or financing agreements. Future maturities of long-term debt at December 31, 2018, were approximately as follows: 2019 $ 149 2020 157 2021 166 2022 173 2023 182 Thereafter 706 $ 1,533

Equity-Based Compensation

Equity-Based Compensation	12 Months Ended
	Dec. 31, 2018
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Equity-Based Compensation	Note 16. Equity-Based Compensation On January 24, 2013, the Board adopted the 2013 Equity Incentive Plan (the “Plan”). In connection with the adoption of the Plan, 500,000 shares of common stock were reserved for issuance pursuant to the Plan, with automatic increases in such reserve available each year annually on January 1 from 2014 through 2023 equal to the lesser of 3.0% of the total outstanding shares of common stock as of December 31 of the immediately preceding year or, a number of shares of common stock determined by the Board, provided that the maximum number of shares authorized under the Plan did not exceed 1,992,241 shares, subject to certain adjustments. The maximum number of shares authorized under the Plan was reached on January 1, 2017. At December 31, 2018, 1,024,185 shares remained available for future issuance under the Plan. Stock options and restricted stock issued by the Company under the Plan are generally subject to service conditions resulting in annual vesting on the anniversary of the date of grant over a period typically ranging between one and three years. Certain stock options and restricted stock issued by the Company under the Plan vest immediately upon issuance. Stock options issued by the Company under the Plan have contractual lives which expire over a period typically ranging between five and ten years from the date of grant subject to continued service to the Company by the participant. On February 7, 2018, the Compensation Committee of the Board adopted the 2018 Annual Incentive Program (the “Program”) as a subplan under the Plan. The Program provided an opportunity for performance-based compensation to senior executive officers of the Company, among others. The target annual incentive for each Program participant was expressed as a percentage of base salary and was conditioned on the achievement of certain financial goals (as approved by the Compensation Committee of the Board) or a combination of financial and non-financial goals. The Compensation Committee of the Board retained negative discretion over amounts payable under the Program. For 2018, the total target amount payable under the Program was approximately $1,423, with certain amounts to be settled with participants in cash, equity or a combination thereof. During 2018, total compensation expense associated with the Program was approximately $460, split between cost of sales ($91), research and development ($127) and selling general and administrative expenses ($242) in the accompanying statement of consolidated operations and comprehensive loss, of which approximately $167 is expected to be settled in equity by the Company. The following table summarizes the total equity-based compensation expense recognized by the Company : 2018 2017 Equity-based compensation expense recognized: Stock options $ 357 $ 1,503 Restricted stock 433 953 Other (a) 178 — Total equity-based compensation expense before income taxes 968 2,456 Benefit for income taxes (b) — — Total equity-based compensation expense net of income taxes $ 968 $ 2,456 (a) Other represents expense associated with the Program and other employee contractual amounts to be settled in equity. (b) The benefit for income taxes from equity-based compensation for each of the periods presented has been determined to be $0 At December 31, 2018, total future compensation expense related to unvested awards yet to be recognized by the Company was approximately $682 The fair value of stock options was estimated on the date of grant using the Black-Scholes option pricing model with the following assumptions: 2018 2017 Weighted average fair value per stock option $2.23 - $4.16 $3.28 - $5.75 Volatility 54.05% - 63.67% 61.68% - 67.92% Average risk-free interest rate 2.45% - 2.98% 1.40% - 1.94% Dividend yield 0.00% 0.00% Expected term (years) 2.5 - 3.3 2.5 - 5.5 For certain stock option awards, volatility is estimated based on the historical volatility of the Company when the expected term of the award is less than the period for which the Company has been publicly traded. For certain stock option awards, volatility is estimated based on the historical volatilities of certain peer group companies when the expected term of the award exceeds the period for which the Company has been publicly traded. The average risk-free rate is based on a weighted average yield curve of risk-free interest rates consistent with the expected term of the awards. Expected dividend yield is based on historical dividend data as well as future expectations. Expected term is calculated using the simplified method as the Company does not have sufficient historical exercise experience upon which to base an estimate. The activity for stock options was as follows: 2018 2017 Number of Stock Options Weighted Average Exercise Price Weighted Average Grant Date Fair Value Number of Stock Options Weighted Average Exercise Price Weighted Average Grant Date Fair Value Outstanding at beginning of period 674,470 $ 11.58 $ 6.41 314,303 $ 15.62 $ 9.38 Stock options granted 258,100 $ 8.01 $ 3.43 389,000 $ 8.16 $ 3.89 Stock options exercised (67,083 ) $ 7.89 $ 3.85 (18,500 ) $ 7.91 $ 3.40 Stock options forfeited (135,169 ) $ 9.48 $ 5.18 (1,167 ) $ 15.74 $ 9.60 Stock options expired (108,332 ) $ 13.28 $ 7.58 (9,166 ) $ 17.59 $ 10.77 Outstanding at end of period 621,986 $ 10.66 $ 5.52 674,470 $ 11.58 $ 6.41 Stock options exercisable at end of period 409,914 $ 11.89 $ 6.44 421,960 $ 12.95 $ 7.39 Stock options expected to vest at end of period 212,072 $ 8.27 $ 3.76 252,510 $ 9.28 $ 4.78 At December 31, 2018, intrinsic value associated with stock options exercisable was approximately $3. At December 31, 2018, there was no intrinsic value associated with stock options expected to vest. The activity for restricted stock was as follows: For the years ended December 31, 2018 2017 Shares of Restricted Stock Weighted Average Grant Date Fair Value Shares of Restricted Stock Weighted Average Grant Date Fair Value Outstanding at beginning of period 52,502 $ 11.07 94,171 $ 14.29 Restricted stock granted 57,000 $ 7.39 60,000 $ 9.01 Restricted stock vested (42,501 ) $ 10.51 (89,002 ) $ 12.67 Restricted stock forfeited — $ — (12,667 ) $ 13.95 Outstanding at end of period 67,001 $ 8.30 52,502 $ 11.07 Restricted stock expected to vest at end of period 67,001 $ 8.30 52,502 $ 11.07 Restricted stock vesting during 2018 and 2017 had a fair value of approximately $326 and $801, respectively.

Income Taxes

Income Taxes	12 Months Ended
	Dec. 31, 2018
Income Tax Disclosure [Abstract]
Income Taxes	Note 17. Income Taxes The components of loss before taxes were as follows: 2018 2017 United States $ (16,262 ) $ (18,064 ) Foreign 3,755 (1,915 ) Loss before income taxes $ (12,507 ) $ (19,979 ) The provision for income taxes consisted of the following: 2018 2017 Current Deferred Total Current Deferred Total United States $ 18 $ — $ 18 $ — $ — $ — Foreign 142 — 142 37 1 38 Provision for income taxes $ 160 $ — $ 160 $ 37 $ 1 $ 38 A reconciliation of the provision for income taxes at the United States statutory rate to the effective rate of the Company for the years ended December 31 was as follows: 2018 2017 United States statutory rate (21.0% for 2018 and 34.0% for 2017) $ (2,626 ) $ (6,793 ) Effect of foreign disregarded entity (129 ) (199 ) Taxes on foreign operations 259 35 Net change in valuation allowances 917 8,017 Indebtedness income not subject to income tax — (1,208 ) Effect of intercompany asset transfers — (182 ) Permanent differences and other 1,739 368 Provision for income taxes $ 160 $ 38 Effective tax rate (1.3 )% (0.2 )% In December 2017, the Tax Cuts and Jobs Act (the “Tax Act”) was enacted into law. The Tax Act reduces the corporate income tax rate from 34.0% to 21.0% and generally modifies certain United States income tax deductions and the United States taxation of certain foreign earnings, among other changes. The Company is required to recognize the effect of tax law changes in the period of enactment. As a result of the Tax Act, the Company re-measured its United States deferred tax assets and liabilities as well as its valuation allowance against its net United States deferred tax assets at December 31, 2017. In December 2017, the SEC staff issued Staff Accounting Bulletin No. 118: Income Tax Accounting Implications of the 2017 Tax Cuts and Jobs Act, which allows the Company to record provisional amounts during a measurement period not to extend beyond one year of the enactment date. No provisional amounts were recorded by the Company due to the valuation allowance on United States net deferred tax assets, and the accounting related to the Tax Act is now complete as of December 31, 2018. The components of deferred income tax assets and liabilities consisted of the following at December 31: 2018 2017 Deferred tax assets Accounts receivable $ 46 $ 311 Inventories 1,077 1,024 Accrued expenses and other current liabilities 489 549 Net operating loss carryforwards 24,419 22,864 Tax credit carryforwards 676 676 Other 1,059 1,495 Valuation allowance (26,563 ) (25,690 ) Total deferred tax assets 1,203 1,229 Deferred tax liabilities Property and equipment 703 689 Other 501 541 Total deferred tax liabilities 1,204 1,230 Net deferred tax liabilities (a) $ 1 $ 1 (a) At December 31, 2018 and 2017, net deferred tax liabilities were reflected in other noncurrent liabilities in the consolidated balance sheet. The Company has provided a valuation allowance for its net deferred tax assets as a result of the Company not generating consistent net operating profits in jurisdictions in which it operates. As such, any benefit from deferred taxes in any of the periods presented has been fully offset by changes in the valuation allowance for net deferred tax assets. The Company continues to assess its future taxable income by jurisdiction based on recent historical operating results, the expected timing of reversal of temporary differences, various tax planning strategies that the Company may be able to enact in future periods, the impact of potential operating changes on the business and forecast results from operations in future periods based on available information at the end of each reporting period. To the extent that the Company is able to reach the conclusion that its net deferred tax assets are realizable based on any combination of the above factors in a single, or in multiple, taxing jurisdictions, a reversal of the related portion of the Company’s existing valuation allowances may occur. The following table summarizes changes to the Company’s valuation allowances for the years ended December 31: 2018 2017 Balance at beginning of period $ 25,690 $ 25,177 Net increases in allowances 1,247 8,017 Tax Act rate change adjustment — (7,670 ) Foreign currency translation and other adjustments (374 ) 166 Balance at end of period $ 26,563 $ 25,690 At December 31, 2018, the Company had approximately $85,674 in net operating loss carryforwards, subject to certain limitations, $70,100 of which expire from 2033 to 2037, and $15,574 of which do not expire, and $676 The Company has a liability for uncertain tax positions related primarily to certain intercompany transactions. A reconciliation of the beginning and ending amount of unrecognized tax benefits (including accrued interest and penalties) at December 31 was as follows: 2018 2017 Balance at beginning of period $ 1,775 $ 1,217 Additions based on tax positions related to the current year 60 219 Additions for tax positions of prior years — 5 Reductions for tax positions of prior years (606 ) — Settlements — (5 ) Foreign currency translation adjustments (43 ) 339 Balance at end of period $ 1,186 $ 1,775 The Company includes interest and penalties related to income taxes as a component of the provision for income taxes in the accompanying statement of consolidated operations and comprehensive loss (there were no such interest or penalties included in the provision for income taxes in 2018 or 2017). At December 31, 2018 and 2017, there were approximately $820 and $858, respectively, in unrecognized tax benefits (including accrued interest and penalties) that if recognized would affect the annual effective tax rate (such amounts were included in accrued expenses and other current liabilities in the accompanying consolidated balance sheet at December 31, 2018 and 2017, respectively). During 2018, in connection with its periodic re-assessment of its uncertain tax positions, the Company determined that the uncertain tax positions related to its ExOne KK (Japan) subsidiary no longer met the more likely than not criteria, and as a result, the related liability was reversed in-full. No amount was recorded as a component of the provision for income taxes due to existing net operating loss carryforwards. The Company files income tax returns in the United States, Germany, Japan, Italy (through 2018) and Sweden (through 2017). The following table summarizes tax years remaining subject to examination for each of the Company’s subsidiaries at December 31, 2018: Jurisdiction Tax Years Remaining Subject to Examination United States 2015-2018 Germany 2010-2018 Japan 2017-2018 Italy 2014-2018 Sweden 2015-2017 At December 31, 2018, the Company’s ExOne GmbH (2010-2013) and ExOne Property GmbH (2013) subsidiaries were under examination by local taxing authorities in Germany. In January 2019 this examination was concluded by the local taxing authorities in Germany without significant adjustment to previously established tax positions. As a result, during the three months ended March 31, 2019, the Company expects to record a reversal of its previously recorded liabilities for uncertain tax positions of approximately $1,187, of which approximately $367 is expected to be offset against net operating loss carryforwards. The Company expects to record the remainder, approximately $820, as a benefit for income taxes during the three months ended March 31, 2019.

Fair Value Measurements

Fair Value Measurements	12 Months Ended
	Dec. 31, 2018
Fair Value Disclosures [Abstract]
Fair Value Measurements	Note 18. Fair Value Measurements Fair value is defined as the price that would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants at the measurement date. When determining the fair value measurements for assets and liabilities which are required to be recorded at fair value, the Company considers the principal or most advantageous market in which the Company would transact and the market-based risk measurements or assumptions that market participants would use in pricing the asset or liability, such as inherent risk, transfer restrictions and credit risk. The Company applies the following fair value hierarchy, which prioritizes the inputs used to measure fair value into three levels and bases the categorization within the hierarchy upon the lowest level of input that is available and significant to the fair value measurement: Level 1 Observable inputs such as quoted prices in active markets for identical investments that the Company has the ability to access. Level 2 Inputs include: Quoted prices for similar assets or liabilities in active markets; Quoted prices for identical or similar assets or liabilities in inactive markets; Inputs, other than quoted prices in active markets, that are observable either directly or indirectly; and Inputs that are derived principally from, or corroborated by, observable market data by correlation or other means. Level 3 Inputs that are generally unobservable and typically reflect management’s estimates of assumptions that market participants would use in pricing the asset or liability. The Company is required to disclose its estimate of the fair value of material financial instruments, including those recorded as assets or liabilities in its consolidated financial statements, in accordance with GAAP. During the three months ended March 31, 2017, the Company entered into two separate foreign exchange forward contracts with a German bank in an effort to hedge the variability of certain foreign exchange risks between the euro (the functional currency of the Company’s ExOne GmbH subsidiary) and British pound sterling (the currency basis for cash flows resulting from a commercial sales arrangement with a customer). The first of the two foreign exchange forward contracts was entered into and settled (in connection with cash received from the customer) during the three months ended March 31, 2017, resulting in a realized gain on settlement of approximately $16 (€15). The second of the two foreign exchange forward contracts was settled on August 31, 2017, resulting in a realized gain on settlement of approximately $14 (€12). Neither of the contracts was designated as a hedging instrument and accordingly, realized and unrealized gains (losses) for all periods have been recorded to other (income) expense – net in the accompanying statement of consolidated operations and comprehensive loss. The Company has classified both contracts as Level 2 fair value measurements. The carrying values and fair values of other financial instruments (assets and liabilities) not required to be recorded at fair value were as follows: December 31, December 31, 2018 2017 Carrying Value Fair Value Carrying Value Fair Value Cash and cash equivalents $ 7,592 $ 7,592 $ 21,848 $ 21,848 Restricted cash $ 1,548 $ 1,548 $ 330 $ 330 Debt issuance costs (a) $ 195 $ — $ — $ — Current portion of long-term debt (b) $ 144 $ 149 $ 137 $ 142 Long-term debt - net of current portion (b) $ 1,364 $ 1,384 $ 1,508 $ 1,533 (a) Represents debt issuance costs associated with the Company’s related party revolving credit facility (Note 14) of which $88 was included in prepaid expenses and other current assets and $107 was included in other noncurrent assets in the accompanying consolidated balance sheet at December 31, 2018 (b) Carrying values at December 31, 2018 and 2017 are net of unamortized debt issuance costs of approximately $20 and $25, respectively. The carrying amounts of cash and cash equivalents, restricted cash and current portion of long-term debt approximate fair value due to their short-term maturities. The fair value of long-term debt – net of current portion has been estimated by management based on the consideration of applicable interest rates (including certain instruments at variable or floating rates). Cash and cash equivalents and restricted cash are classified in Level 1; current portion of long-term debt and long-term debt – net of current portion are classified in Level 2.

Concentration of Credit Risk

Concentration of Credit Risk	12 Months Ended
	Dec. 31, 2018
Risks And Uncertainties [Abstract]
Concentration of Credit Risk	Note 19. Concentration of Credit Risk During 2018 and 2017, the Company conducted a significant portion of its business with a limited number of customers, though not necessarily the same customers for each respective period. During 2018 and 2017, the Company’s five most significant customers represented approximately 16.5% and 20.5% of total revenue, respectively. At December 31, 2018 and 2017, accounts receivable from the Company’s five most significant customers were approximately $2,344

Related Party Transactions

Related Party Transactions	12 Months Ended
	Dec. 31, 2018
Related Party Transactions [Abstract]
Related Party Transactions	Note 20. Related Party Transactions Revenues During 2017, sales of products and/or services to related parties were approximately $33. None of the transactions met a threshold requiring review and approval by the Audit Committee of the Board of Directors in accordance with Company policy. There were no sales of products and/or services to related parties during 2018. There were no amounts due from related parties at December 31, 2018 or 2017. Expenses During 2018 and 2017, purchases of products and/or services from related parties were approximately $27 and $14, respectively. Purchases of products and/or services by the Company during 2018 and 2017 included website design services and leased office space from related parties under common control by S. Kent Rockwell, who is the Chairman and Chief Executive Officer of the Company and prior to June 20, 2018, was the Executive Chairman of the Company. None of the transactions met a threshold requiring review and approval by the Audit Committee of the Board in accordance with Company policy. Amounts due to related parties at both December 31, 2018 and 2017 were approximately $1 and are reflected in accounts payable in the accompanying consolidated balance sheet. The Company also receives the benefit of the corporate use of an airplane from a related party under common control by S. Kent Rockwell, who is the Chairman and Chief Executive Officer of the Company and prior to June 20, 2018, was the Executive Chairman of the Company, Other Refer to Note 14 for further discussion relating to a revolving credit facility with a related party entered into in March 2018.

Other (Income) Expense _ Net

Other (Income) Expense – Net	12 Months Ended
	Dec. 31, 2018
Other Income And Expenses [Abstract]
Other (Income) Expense – Net	Note 21. Other (Income) Expense – Net Other (income) expense – net consisted of the following: 2018 2017 Gain on settlement of insurance claim $ (819 ) $ (1 ) Interest income (39 ) (56 ) Foreign currency losses – net 93 199 Bank fees 95 122 Other – net (74 ) (61 ) $ (744 ) $ 203 For 2018, gain on settlement of insurance claim represented approximately $819 of a realized gain associated with an insurance recovery for a 3D printing machine damaged by a third party freight company while in transit. For 2018, foreign currency losses – net included approximately $245 of a foreign exchange loss associated with settlement of an intercompany note payable with ExOne Italy S.r.l. pr

Segment, Product and Geographic

Segment, Product and Geographic Information	12 Months Ended
	Dec. 31, 2018
Segment Reporting [Abstract]
Segment, Product and Geographic Information	Note 22. Segment, Product and Geographic Information The Company manages its business globally in a singular operating segment in which it develops, manufactures and markets 3D printing machines, 3D printed and other products, materials and services. Geographically, the Company conducts its business through wholly-owned subsidiaries in the United States, Germany, Japan, Italy (through December 2018) and Sweden (through December 2017). Revenue by product group for the year ended December 31 was as follows: 2018 2017 3D printing machines $ 36,393 $ 29,980 3D printed and other products, materials and services 28,251 27,764 $ 64,644 $ 57,744 Geographic information for revenue for the year ended December 31 was as follows (based on the country where the sale originated): 2018 2017 United States $ 29,514 $ 25,008 Germany 27,084 27,497 Japan 8,027 4,115 Italy (a) 19 917 Sweden (b) — 207 $ 64,644 $ 57,744 (a) In December 2017 the Company committed to a plan to consolidate certain of its 3D printing operations from its Desenzano del Garda, Italy facility into its Gersthofen, Germany facility (Note 5) . Operations at the Desenzano del Garda, Italy facility effectively ceased during the three months ended March 31, 2018 and in December 2018, the Company completed the dissolution of its ExOne Italy S.r.l. subsidiary. (b) In March 2017 the Company terminated its Cooperation Agreement with Swerea SWECAST AB (“Swerea”), resulting in an exit of its PSC/EAC operations in Jönköping, Sweden, effective April 1, 2017. Also in March 2017 the Company agreed to an operating lease agreement with Beijer Industri AB, effective April 1, 2017, related to the 3D printing machine and related equipment located on the Swerea premises, previously covered under the Cooperation Agreement with Swerea Geographic information for long-lived assets at December 31 was as follows (based on the physical location of assets): 2018 2017 United States $ 13,603 $ 14,873 Germany 23,249 25,748 Japan 4,650 4,996 Italy (a) 199 796 Sweden (b) 205 273 United Kingdom (c) — 111 $ 41,906 $ 46,797 (a) In December 2017 the Company committed to a plan to consolidate certain of its 3D printing operations from its Desenzano del Garda, Italy facility into its Gersthofen, Germany facility (Note 5) . Operations at the Desenzano del Garda, Italy facility effectively ceased during the three months ended March 31, 2018 and in December 2018, the Company completed the dissolution of its ExOne Italy S.r.l. subsidiary. At December 31, 2018, long-lived assets represent a 3D printing machine and related equipment held by the Company under an operating lease agreement with a customer. At December 31, 2017, long-lived assets represent certain machinery and other equipment associated with the former Desenzano del Garda facility. (b) At December 31, 2018 and 2017, represents a 3D printing machine and related equipment held by the Company under an operating lease agreement with a customer. (c) At December 31, 2017, represents a 3D printing machine and related equipment held by the Company under an operating lease agreement with a customer. This customer agreement was terminated during 2018.

Subsequent Events

Subsequent Events	12 Months Ended
	Dec. 31, 2018
Subsequent Events [Abstract]
Subsequent Events	Note 23. Subsequent Events Refer to Note 17 for further discussion relating to the conclusion of a tax examination, which qualifies as a reportable subsequent event. The Company has evaluated all of its activities and concluded that no other subsequent events have occurred that would require recognition in the consolidated financial statements or disclosure in the notes to the consolidated financial statements, except as described above.

Summary of Significant Accoun_2

Summary of Significant Accounting Policies (Policies)	12 Months Ended
	Dec. 31, 2018
Accounting Policies [Abstract]
Organization	Organization The ExOne Company (“ExOne”) is a corporation organized under the laws of the state of Delaware. ExOne was formed on January 1, 2013, when The Ex One Company, LLC, a Delaware limited liability company, merged with and into a Delaware corporation, which survived and changed its name to The ExOne Company (the “Reorganization”). As a result of the Reorganization, The Ex One Company, LLC became ExOne, the common and preferred interest holders of The Ex One Company, LLC became holders of common stock and preferred stock, respectively, of ExOne and the subsidiaries of The Ex One Company, LLC became the subsidiaries of ExOne. The consolidated financial statements include the accounts of ExOne and its wholly-owned subsidiaries, ExOne Americas LLC (United States); ExOne GmbH (Germany); ExOne Property GmbH (Germany); ExOne KK (Japan); through December 2018, ExOne Italy S.r.l. (Italy); and through December 2017, ExOne Sweden AB (Sweden). Collectively, the consolidated group is referred to as the “Company”. On December 31, 2017, the Company completed a dissolution of its ExOne Sweden AB (Sweden) subsidiary. The purpose of this dissolution was to further simplify the Company’s legal structure. There were no significant accounting or tax related impacts associated with the dissolution of this subsidiary. On December 28, 2018, the Company completed a dissolution of its ExOne Italy S.r.l. (Italy) subsidiary. The purpose of this dissolution was to further simplify the Company’s legal structure. In connection with the dissolution, the Company settled an intercompany note payable with ExOne Italy S.r.l. pr eviously identified as a long-term investment in the subsidiary. This settlement resulted in the recognition of a $245 foreign exchange loss (recorded as a component of other (income) expense – net in the accompanying statement of consolidated operations and comprehensive loss). The Company filed a registration statement on Form S-3 (No. 333-223690) with the Securities and Exchange Commission (“SEC”) on March 15, 2018. The purpose of the Form S-3 was to register, among other securities, debt securities. Subsidiaries of the Company are co-registrants with the Company (“Subsidiary Guarantors”), and the registration statement registered guarantees of debt securities by one or more of the Subsidiary Guarantors. The Subsidiary Guarantors are 100% owned by the Company and any guarantees by the Subsidiary Guarantors will be full and unconditional . Basis of Presentation The consolidated financial statements of the Company are prepared in conformity with accounting principles generally accepted in the United States of America (“GAAP”). All material intercompany transactions and balances have been eliminated in consolidation. Certain amounts relating to current portion of capital leases ($15) and capital leases – net of current portion ($36) in the accompanying consolidated balance sheet at December 31, 2017, have been reclassified to accrued expenses and other current liabilities and other noncurrent liabilities, respectively, to conform to current period presentation.
Use of Estimates	Use of Estimates The preparation of these consolidated financial statements requires the Company to make certain judgments, estimates and assumptions regarding uncertainties that affect the reported amounts of assets, liabilities, revenue and expenses and related disclosure of contingent assets and liabilities. Areas that require significant judgments, estimates and assumptions include accounting for accounts receivable (including the allowance for doubtful accounts); inventories (including the allowance for slow-moving and obsolete inventories); product warranty reserves; contingencies; income taxes (including the valuation allowance on certain deferred tax assets and liabilities for uncertain tax positions); equity-based compensation (including the valuation of certain equity-based compensation awards issued by the Company); and testing for impairment of long-lived assets (including the identification of asset groups by management, estimates of future cash flows of identified asset groups and fair value estimates used in connection with assessing the valuation of identified asset groups). The Company bases its estimates on historical experience and on various other assumptions that are believed to be reasonable, the results of which form the basis for making judgments about the carrying values of assets and liabilities that are not readily apparent from other sources. Actual results may differ from these estimates.
Foreign Currency	Foreign Currency The local currency is the functional currency for significant operations outside of the United States. The determination of the functional currency of an operation is made based upon the appropriate economic and management indicators. Foreign currency assets and liabilities are translated into their United States dollar equivalents based upon year end exchange rates, and are included in stockholders’ equity as a component of other comprehensive income (loss). Revenues and expenses are translated at average exchange rates. Transaction gains and losses that arise from exchange rate fluctuations are charged to operations as incurred, except for gains and losses associated with certain long-term intercompany transactions between subsidiaries for which settlement is not planned or anticipated in the foreseeable future, which are included in other comprehensive income (loss) in the accompanying statement of consolidated operations and comprehensive loss. The Company transacts business globally and is subject to risks associated with fluctuating foreign exchange rates. Approximately 54.3%
Revenue Recognition	Revenue Recognition The Company derives revenue from the sale of 3D printing machines and 3D printed and other products, materials and services. Revenue is recognized by the Company when persuasive evidence of an arrangement exists, delivery has occurred (generally when title and risk and rewards of ownership have transferred to the customer) or services have been rendered, selling price is fixed or determinable and collectability is reasonably assured. The Company enters into arrangements that may provide for multiple deliverables to a customer. Sales of 3D printing machines may also include optional equipment, materials, replacement components and services (installation, training and other services, including maintenance services and/or an extended warranty). The Company identifies all products and services that are to be delivered separately under an arrangement and allocates revenue to each based on their relative fair value. Fair values are generally established based on the prices charged when sold separately by the Company (vendor specific objective evidence). The allocated revenue for each deliverable is then recognized ratably based on relative fair values of the components of the sale. In the absence of vendor specific objective evidence or third party evidence in leading to a relative fair value for a sale component, the Company’s best estimate of selling price is used. The Company also evaluates the impact of undelivered items on the functionality of delivered items for each sales transaction and, where appropriate, defers revenue on delivered items when that functionality has been affected. Functionality is determined to be met if the delivered products or services represent a separate earnings process. The Company’s arrangements for 3D printing machines generally include substantive customer acceptance provisions for which the Company must determine whether it can objectively demonstrate that either company-specific or customer-specific criteria identified in such provisions have been met prior to recognizing revenue on the transaction. Revenue is generally deferred on all such arrangements until formal acceptance is provided from the customer. The Company generally provides customers with a standard twelve month warranty on its 3D printing machines. The standard warranty is not treated as a separate service because the standard warranty is an integral part of the sale of the 3D printing machine. At the time of sale, a liability is recorded (with an offset to cost of sales) based upon the expected cost of replacement parts and labor to be incurred over the life of the standard warranty. Following the standard warranty period, the Company offers its customers optional maintenance service contracts or extended warranties. Deferred maintenance service revenues are generally recognized when the maintenance services are performed since the Company has historical evidence that indicates that the costs of performing the services under the contract are not incurred on a straight-line basis. The Company sells equipment with embedded software to its customers. The embedded software is not sold separately and it is not a significant focus of the Company’s marketing effort. The Company does not provide post-contract customer support specific to the software or incur significant costs that are within the scope of Financial Accounting Standards Board (“FASB”) guidance on accounting for software to be leased or sold. Additionally, the functionality that the software provides is marketed as part of the overall product. The software embedded in the equipment is incidental to the equipment as a whole such that the FASB guidance referenced above is not applicable. Sales of these products are recognized in accordance with FASB guidance on accounting for multiple-element arrangements. Shipping and handling costs billed to customers are included in revenue in the accompanying statement of consolidated operations and comprehensive loss. Costs incurred by the Company associated with shipping and handling are included in cost of sales in the accompanying statement of consolidated operations and comprehensive loss. In assessing collectability as part of the revenue recognition process, the Company considers a number of factors in its evaluation of the creditworthiness of the customer, including past due amounts, past payment history, and current economic conditions. If it is determined that collectability cannot be reasonably assured, the Company will defer recognition of revenue until collectability is assured. For 3D printing machines, the Company’s terms of sale vary by transaction. To reduce credit risk in connection with 3D printing machine sales, the Company may, depending upon the circumstances, require customers to furnish letters of credit or bank guarantees or to provide advanced payment (either partial or in full). Prepayments received from customers are reported as deferred revenue and customer prepayments in the accompanying consolidated balance sheet. For 3D printed and other products and materials, the Company’s terms of sale generally require payment within 30 to 60 days after delivery, although the Company also recognizes that longer payment periods are customary in certain countries where it transacts business. Service arrangements are generally billed in accordance with specific contract terms and are typically billed in advance or in proportion to performance of the related services. The Company has entered into certain contracts for the sale of its products and services with the federal government under fixed-fee, cost reimbursable and time and materials arrangements. With respect to cost reimbursable arrangements with the federal government, the Company generally bills for products and services in accordance with provisional rates as determined by the Company. To the extent that provisional rates billed under these contracts differ from actual experience, a billing adjustment (through revenue) is made in the period in which the difference is identified (generally upon completion of its annual Incurred Cost Submission filing as required by the federal government). For 2018 and 2017, revenues and any adjustments related to these contracts were not significant.
Cash and Cash Equivalents	Cash and Cash Equivalents The Company considers all highly liquid instruments with maturities when purchased of three months or less to be cash equivalents. The Company’s policy is to invest cash in excess of short-term operating and debt-service requirements in such cash equivalents. These instruments are stated at cost, which approximates fair value because of the short maturity of the instruments. The Company maintains cash balances with financial institutions located in the United States, Germany and Japan. The Company places its cash with high quality financial institutions and believes its risk of loss is limited; however, at times, account balances may exceed international and federally insured limits. The Company has not experienced any losses associated with these cash balances.
Accounts Receivable and Net Investment in Sales-Type Leases	Accounts Receivable and Net Investment in Sales-Type Leases Accounts receivable and net investment in sales-type leases are reported at their net realizable value. The Company carries its investment in sales-type leases based on discounting the minimum lease payments by the interest rate implicit in the lease and less an allowance for doubtful accounts. write-off and collections experience, current credit conditions, the age of the related balances and economic factors that may affect a customer’s ability to pay.
Inventories	Inventories The Company values all of its inventories at the lower of cost, as determined on the first-in, first-out method or net realizable value. Overhead is allocated to work in process and finished goods based upon normal capacity of the Company’s production facilities. Fixed overhead associated with production facilities that are being operated below normal capacity are recognized as a period expense rather than being capitalized as a product cost. An allowance for slow-moving and obsolete inventories is provided based on historical consumption experience, anticipated product demand and product design changes. These provisions reduce the cost basis of the respective inventories and are recorded as a charge to cost of sales.
Property and Equipment	Property and Equipment Property and equipment are recorded at cost and depreciated on a straight-line basis over the estimated useful lives of the related assets, generally three to forty years. Leasehold improvements are amortized on a straight-line basis over the shorter of their estimated useful lives or the estimated or contractual lives of the related leases. Gains or losses from the sale of assets are recognized upon disposal or retirement of the related assets. Repairs and maintenance are charged to expense as incurred. The Company evaluates long-lived assets held and used for impairment whenever events or changes in circumstances indicate that the carrying amount of such assets (asset group) may not be recoverable. Recoverability of assets is determined by comparing the estimated undiscounted net cash flows of the operations related to the assets (asset group) to their carrying amount. An impairment loss would be recognized when the carrying amount of the assets (asset group) exceeds the estimated undiscounted net cash flows. The amount of the impairment loss to be recorded is calculated as the excess of carrying value of assets (asset group) over their fair value. The determination of what constitutes an asset group, the associated undiscounted net cash flows, the fair value of assets (asset group) and the estimated useful lives of assets require significant judgments and estimates by management. No impairment loss related to held and used assets was recorded by the Company during 2018 or 2017. The Company evaluates long-lived assets held for sale for impairment when the associated long-lived asset (asset group) is first determined to meet the held for sale criteria and in each reporting period thereafter until a disposal is executed or a change in plan occurs. A long-lived asset (asset group) is first determined to meet the held for sale criteria when: management, having the authority to approve the action, commits to a plan to sell the long-lived asset (asset group); the long-lived asset (asset group) is available for immediate sale in its present condition subject only to terms that are usual and customary for sales of such long-lived assets (asset groups); an active program to locate a buyer and other actions required to complete the plan to sell the long-lived asset (asset group) have been initiated; the sale of the long-lived asset (asset group) is probable, and transfer of the long-lived asset (asset group) is expected to qualify for recognition as a completed sale, within one year; the long-lived asset (asset group) is being actively marketed for sale at a price that is reasonable in relation to its current fair value; and actions required to complete the plan indicate that it is unlikely that significant changes to the plan will be made or that the plan will be withdrawn. In connection with the Company’s exit of its Houston, Texas facility (Note 5), the Company reclassified approximately $822 in property and equipment (principally land and building) associated with certain long-lived assets meeting required criteria as held for sale (included in prepaid expenses and other current assets in the accompanying consolidated balance sheet at December 31, 2018).
Product Warranty Reserves	Product Warranty Reserves Substantially all of the Company’s 3D printing machine sales are covered by a standard twelve month warranty. Generally, at the time of sale, a liability is recorded (with an offset to cost of sales) based upon the expected cost of replacement parts and labor to be incurred over the life of the standard warranty. Expected cost is estimated using historical experience for similar products. The Company periodically assesses the adequacy of the product warranty reserves based on changes in these factors and records any necessary adjustments if actual experience indicates that adjustments are necessary. Future claims experience could be materially different from prior results because of the introduction of new, more complex products, a change in the Company’s warranty policy in response to industry trends, competition or other external forces, or manufacturing changes that could impact product quality. In the event that the Company determines that its current or future product repair and replacement costs exceed estimates, an adjustment to these reserves would be charged to cost of sales in the period such a determination is made.
Income Taxes	Income Taxes The provision for income taxes is determined using the asset and liability approach of accounting for income taxes. Under this approach, the provision for income taxes represents income taxes paid or payable (or received or receivable) for the current year plus the change in deferred taxes during the year. Deferred taxes represent the future tax consequences expected to occur when the reported amounts of assets and liabilities are recovered or paid, and result from differences between the financial and tax bases of assets and liabilities and are adjusted for changes in tax rates and tax laws when enacted. Valuation allowances are established when necessary to reduce deferred tax assets to the amount expected to be realized. The Company’s foreign subsidiaries are taxed as corporations under the taxing regulations of those respective countries. As a result, the accompanying statement of consolidated operations and comprehensive loss includes a provision for income taxes related to these foreign jurisdictions. Any undistributed earnings are intended to be permanently reinvested in the respective subsidiaries. The Company recognizes the income tax benefit from an uncertain tax position only if it is more likely than not that the income tax position will be sustained on examination by the taxing authorities based upon the technical merits of the position. The income tax benefits recognized in the consolidated financial statements from such positions are then measured based upon the largest amount that has a greater than 50% likelihood of being realized upon settlement. Income tax benefits that do not meet the more likely than not criteria are recognized when effectively settled, which generally means that the statute of limitations has expired or that the appropriate taxing authority has completed its examination even though the statute of limitations remains open. Interest and penalties related to uncertain tax positions are recognized as part of the provision for income taxes and are accrued beginning in the period that such interest and penalties would be applicable under relevant tax law until such time that the related income tax benefits are recognized.
Taxes on Revenue Producing Transactions	Taxes on Revenue Producing Transactions Taxes assessed by governmental authorities on revenue producing transactions, including sales, excise, value added and use taxes, are recorded on a net basis (excluded from revenue) in the accompanying statement of consolidated operations and comprehensive loss.
Research and Development	Research and Development The Company is involved in research and development of new methods and technologies relating to its products. Research and development expenses are charged to operations as they are incurred. The Company capitalizes the cost of certain materials, equipment and facilities that have alternative future uses in research and development projects or otherwise.
Advertising	Advertising Advertising costs are charged to expense as incurred, and were not significant for 2018 or 2017.
Defined Contribution Plan	Defined Contribution Plan The Company sponsors a defined contribution savings plan under section 401(k) of the Internal Revenue Code. Under the plan, participating employees in the United States may elect to defer a portion of their pre-tax earnings, up to the Internal Revenue Service’s annual contribution limit. During 2018 and 2017 the Company made discretionary matching contributions of 50% of the first 8% of employee contributions, subject to certain Internal Revenue Service limitations. Discretionary matching contributions made by the Company during 2018 and 2017 were approximately $320 and $303, respectively.
Equity-Based Compensation	Equity-Based Compensation The Company recognizes compensation expense for equity-based grants using the straight-line attribution method in which the expense is recognized ratably over the requisite service period based on the grant date fair value of the related award. Forfeitures of pre-vesting equity-based grants are recognized as they are incurred and result in an offset to equity-based compensation expense in the period of recognition. Fair value of equity-based awards is estimated on the date of grant using the Black-Scholes option pricing model.
Recently Adopted and Issued Accounting Guidance	Recently Adopted Accounting Guidance On January 1, 2018, the Company adopted 2017-09, “Compensation – Stock Compensation: Scope of Modification Accounting.” This ASU requires registrants to apply modification accounting unless three specific criteria are met. The three criteria are: the fair value of the award is the same before and after the modification, the vesting conditions are the same before and after the modification and the classification as a debt or equity award is the same before and after the modification. Management has determined that the adoption of this ASU did not have an impact on the consolidated financial statements of the Company. On January 1, 2017, the Company adopted FASB ASU 2016-16, “Income Taxes: Intra-Entity Transfers of Assets Other Than Inventory.” This ASU modifies existing guidance and is intended to reduce diversity in practice with respect to the accounting for the income tax consequences of intra-entity transfers of assets. The ASU indicates that the former exception to income tax accounting that requires companies to defer the income tax effects of certain intercompany transactions would apply only to intercompany inventory transactions. That is, the exception no longer applies to intercompany sales and transfers of other assets ( e.g. e.g. Recently Issued Accounting Guidance The Company considers the applicability and impact of all ASUs issued by the FASB. Recently issued ASUs not listed below either were assessed and determined to be not applicable or are currently expected to have no impact on the consolidated financial statements of the Company. In August 2016, the FASB issued ASU 2016-15, “Statement of Cash Flows: Classification of Certain Cash Receipts and Cash Payments.” This ASU is intended to reduce diversity in practice in how certain cash receipts and payments are presented and classified in the statement of cash flows. The standard provides guidance in a number of situations including, among others, settlement of zero-coupon bonds, contingent consideration payments made after a business combination, proceeds from the settlement of insurance claims, and distributions received from equity method investees. The ASU also provides guidance for classifying cash receipts and payments that have aspects of more than one class of cash flows. This guidance became effective for the Company on January 1, 2019. Management has determined that the adoption of this ASU will not have an effect on the consolidated financial statements of the Company. In June 2016, the FASB issued ASU 2016-13, “Financial Instruments – Credit Losses.” This ASU added a new impairment model (known as the current expected credit loss (“CECL”) model) that is based on expected losses rather than incurred losses. Under the new guidance, an entity recognizes as an allowance its estimate of expected credit losses. The CECL model applies to most debt instruments, trade receivables, lease receivables, financial guarantee contracts, and other loan commitments. The CECL model does not have a minimum threshold for recognition of impairment losses and entities will need to measure expected credit losses on assets that have a low risk of loss. These changes become effective for the Company on January 1, 2020. Management is currently evaluating the potential impact of these changes on the consolidated financial statements of the Company. In February 2016, the FASB issued ASU 2016-02, “Leases.” This ASU requires lessees to recognize a right-of-use asset and lease liability on the consolidated balance sheet for leases classified as operating leases. For leases with a term of 12 months or less, a lessee is permitted to make an accounting policy election by class of underlying asset not to recognize a right-of-use asset and lease liability. Additionally, when measuring assets and liabilities arising from a lease, optional payments should be included only if the lessee is reasonably certain to exercise an option to extend the lease, exercise a purchase option, or not exercise an option to terminate the lease. A right-of-use asset represents an entity’s right to use the underlying asset for the lease term, and a lease liability represents an entity’s obligation to make lease payments. Currently, an asset and liability only are recorded for leases classified as capital leases (financing leases). The measurement, recognition, and presentation of expenses and cash flows arising from leases by a lessee remains the same. This guidance became effective for the Company on January 1, 2019. In connection with the adoption of this guidance, the Company has completed an assessment resulting in an accumulation of all of its leasing arrangements and has validated the information for accuracy and completeness. Upon adoption of the new lease guidance, management expects to record a right-of-use asset and lease liability, each in the amount of approximately $400, on the Company’s consolidated balance sheet for various types of operating leases, including certain machinery and other equipment and vehicles. This amount is equivalent to the aggregate future minimum lease payments on a discounted basis. The Company has also elected to apply the package of transitional practical expedients of the new lease guidance by allowing the Company to not: (1) reassess if expired or existing contracts are, or contain, leases; (2) reassess lease classification for any expired or existing leases; and (3) reassess initial direct costs for any existing leases. Additionally, in July 2018, the FASB issued guidance to provide for an alternative transition method to the new lease guidance, whereby an entity can choose to not reflect the impact of the new lease guidance in the prior periods included in its consolidated financial statements. The Company plans to utilize this alternative transition method in connection with its adoption on January 1, 2019. In May 2014, the FASB issued ASU 2014-09, “Revenue from Contracts with Customers.” This ASU created a comprehensive framework for all entities in all industries to apply in the determination of when to recognize revenue and, therefore, supersedes virtually all existing revenue recognition requirements and guidance. This framework is expected to provide a consistent and comparable methodology for revenue recognition. The core principle of the guidance is that an entity should recognize revenue 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. To achieve this principle, an entity should apply the following steps: identify the contract(s) with a customer, identify the performance obligations in the contract(s), determine the transaction price, allocate the transaction price to the performance obligations in the contract(s), and recognize revenue when, or as, the entity satisfies a performance obligation. In August 2015, the FASB issued ASU 2015-14, “Revenue from Contracts with Customers: Deferral of the Effective Date,” which deferred the effective date of this guidance for the Company until January 1, 2019. The Company adopted this guidance on January 1, 2019, using the modified retrospective approach. Revenue from the Company’s sale of 3D printing machines and 3D printed and other products, materials and services continues to generally be recognized when the related machines, products or materials are delivered or accepted by the Company’s customers or as the related services are performed by the Company. As such, the adoption of this guidance did not have a material impact on the Company’s financial position or results of operations. The Company expects to include the enhanced disclosures required by this guidance in its consolidated financial statements for the three months ended March 31, 2019.

Basis of Presentation (Policies

Basis of Presentation (Policies)	12 Months Ended
	Dec. 31, 2018
Accounting Policies [Abstract]
Loss Per Share	The Company presents basic and diluted loss per common share amounts. Basic loss per common share is calculated by dividing net loss available to common stockholders by the weighted average number of common shares outstanding during the applicable period. Diluted loss per share is calculated by dividing net loss available to common stockholders by the weighted average number of common shares and common equivalent shares outstanding during the applicable period.

Accumulated Other Comprehensi_2

Accumulated Other Comprehensive Loss (Tables)	12 Months Ended
	Dec. 31, 2018
Equity [Abstract]
Summary of Changes in the Components of Accumulated Other Comprehensive Loss	The following table summarizes changes in the components of accumulated other comprehensive loss: For the years ended December 31, 2018 2017 Foreign currency translation adjustments Balance at beginning of period $ (9,484 ) $ (14,735 ) Other comprehensive (loss) income before reclassifications (1,573 ) 5,251 Amounts reclassified from accumlated other comprehensive loss 309 — Balance at end of period $ (10,748 ) $ (9,484 )

Loss Per Share (Tables)

Loss Per Share (Tables)	12 Months Ended
	Dec. 31, 2018
Earnings Per Share [Abstract]
Computation of Basic and Diluted Loss Per Common Share	The information used to compute basic and diluted net loss per common share was as follows: For the years ended December 31, 2018 2017 Net loss $ (12,667 ) $ (20,017 ) Weighted average shares outstanding (basic and diluted) 16,176,415 16,062,424 Net loss per common share: Basic $ (0.78 ) $ (1.25 ) Diluted $ (0.78 ) $ (1.25 )

Cash, Cash Equivalents, and R_2

Cash, Cash Equivalents, and Restricted Cash (Tables)	12 Months Ended
	Dec. 31, 2018
Cash And Cash Equivalents [Abstract]
Schedule of Reconciliation of Cash, Cash Equivalents and Restricted Cash	The following provides a reconciliation of cash, cash equivalents, and restricted cash as reported in the accompanying consolidated balance sheet to the same such amounts shown in the accompanying statement of consolidated cash flows at December 31: 2018 2017 Cash and cash equivalents $ 7,592 $ 21,848 Restricted cash 1,548 330 Total cash, cash equivalents, and restricted cash shown in the statement of consolidated cash flows $ 9,140 $ 22,178

Inventories (Tables)

Inventories (Tables)	12 Months Ended
	Dec. 31, 2018
Inventory Disclosure [Abstract]
Schedule of Inventories	Inventories consisted of the following at December 31: 2018 2017 Raw materials and components $ 7,747 $ 7,171 Work in process 5,147 4,630 Finished goods 3,036 3,629 $ 15,930 $ 15,430

Long-Lived Assets (Tables)

Long-Lived Assets (Tables)	12 Months Ended
	Dec. 31, 2018
Long-Lived Assets [Line Items]
Summary of Property and Equipment	Property and equipment consisted of the following at December 31: 2018 2017 Economic Life (in years) Land $ 7,024 $ 7,205 N/A Buildings and related improvements 25,895 27,785 5 - 40 Machinery and equipment 20,667 22,034 3 - 20 Other 7,121 6,772 3 - 20 60,707 63,796 Less: Accumulated depreciation (19,306 ) (17,739 ) 41,401 46,057 Construction-in-progress 505 740 Property and equipment - net $ 41,906 $ 46,797
Future Minimum Lease Payments of Operating Lease Arrangements	Future minimum lease payments of operating lease arrangements (with initial terms greater than twelve months) at December 31, 2018, were approximately as follows: 2019 $ 170 2020 111 2021 76 2022 67 2023 12 Thereafter 5 $ 441
Schedule of Intangible Assets	Intangible assets consisted of the following at December 31: 2018 Gross Amount Accumulated Amortization Net Unpatented technology $ 1,388 $ (1,388 ) $ — Trade names 30 (30 ) — $ 1,418 $ (1,418 ) $ — 2017 Gross Amount Accumulated Amortization Net Unpatented technology $ 1,453 $ (1,392 ) $ 61 Trade names 31 (30 ) 1 $ 1,484 $ (1,422 ) $ 62
Machinery and Equipment [Member]
Long-Lived Assets [Line Items]
Future Minimum Lease Payments of Operating Lease Arrangements	Minimum future rentals of machinery and equipment under non-cancellable arrangements at December 31, 2018, were as follows: 2019 $ 687 2020 148 2021 48 2022 — 2023 — Thereafter — $ 883

Net Investment in Sales-Type _2

Net Investment in Sales-Type Leases (Table)	12 Months Ended
	Dec. 31, 2018
Leases [Abstract]
Schedule of Net Investment in Sales-Type Leases	The Company’s net investment in sales-type leases consisted of the following at December 31: 2018 2017 Future minimum lease payments receivable $ 1,969 $ 1,100 Less: Unearned interest income (316 ) (159 ) Net investment in sales-type leases $ 1,653 $ 941
Schedule of Future Minimum Lease Payments Due From Customers Under Sales-Type Leases	Future minimum lease payments due from customers under sales-type leases as of December 31, 2018 were as follows: 2019 $ 409 2020 382 2021 382 2022 382 2023 414 Thereafter — $ 1,969

Accrued Expenses and Other Cu_2

Accrued Expenses and Other Current Liabilities (Tables)	12 Months Ended
	Dec. 31, 2018
Payables And Accruals [Abstract]
Schedule of Accrued Expenses and Other Current Liabilities	Accrued expenses and other current liabilities consisted of the following at December 31: 2018 2017 Accrued payroll and related costs $ 1,895 $ 2,044 Product warranty reserves 1,670 1,300 Liability for uncertain tax positions 820 858 Accrued license fees 721 397 Accrued professional fees 215 223 Value-added taxes payable 140 28 Accrued sales commissions 123 307 Accrued property taxes 108 99 Income taxes payable 90 32 Other 267 808 $ 6,049 $ 6,096

Product Warranty Reserves (Tabl

Product Warranty Reserves (Tables)	12 Months Ended
	Dec. 31, 2018
Product Warranties Disclosures [Abstract]
Summary of Changes in Product Warranty Reserves	The following table summarizes changes in product warranty reserves (such amounts reflected in accrued expenses and other current liabilities in the accompanying consolidated balance sheet): For the years ended December 31, 2018 2017 Balance at beginning of period $ 1,300 $ 1,115 Provisions for new issuances 1,803 1,288 Payments (960 ) (701 ) Reserve adjustments (434 ) (500 ) Foreign currency translation adjustments (39 ) 98 Balance at end of period $ 1,670 $ 1,300

Contingencies and Commitments (

Contingencies and Commitments (Tables)	12 Months Ended
	Dec. 31, 2018
Commitments And Contingencies Disclosure [Abstract]
Future Minimum Lease Payments of Operating Lease Arrangements	Future minimum lease payments of operating lease arrangements (with initial terms greater than twelve months) at December 31, 2018, were approximately as follows: 2019 $ 170 2020 111 2021 76 2022 67 2023 12 Thereafter 5 $ 441

Long-Term Debt (Tables)

Long-Term Debt (Tables)	12 Months Ended
	Dec. 31, 2018
Debt Disclosure [Abstract]
Components of Long-Term Debt	Long-term debt consisted of the following at December 31: 2018 2017 Principal Unamortized Debt Issuance Costs Net Principal Unamortized Debt Issuance Costs Net Building note payable $ 1,533 $ (25 ) $ 1,508 $ 1,675 $ (30 ) $ 1,645 Less: Amount due within one year (149 ) 5 (144 ) (142 ) 5 (137 ) $ 1,384 $ (20 ) $ 1,364 $ 1,533 $ (25 ) $ 1,508
Future Maturities of Long-Term Debt	Future maturities of long-term debt at December 31, 2018, were approximately as follows: 2019 $ 149 2020 157 2021 166 2022 173 2023 182 Thereafter 706 $ 1,533

Equity-Based Compensation (Tabl

Equity-Based Compensation (Tables)	12 Months Ended
	Dec. 31, 2018
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Summary of Equity-Based Compensation Expense	The following table summarizes the total equity-based compensation expense recognized by the Company : 2018 2017 Equity-based compensation expense recognized: Stock options $ 357 $ 1,503 Restricted stock 433 953 Other (a) 178 — Total equity-based compensation expense before income taxes 968 2,456 Benefit for income taxes (b) — — Total equity-based compensation expense net of income taxes $ 968 $ 2,456 (a) Other represents expense associated with the Program and other employee contractual amounts to be settled in equity. (b) The benefit for income taxes from equity-based compensation for each of the periods presented has been determined to be $0
Assumptions for Fair Value of Stock Options Granted Estimated on the Date of Grant Using the Black-Scholes Option	The fair value of stock options was estimated on the date of grant using the Black-Scholes option pricing model with the following assumptions: 2018 2017 Weighted average fair value per stock option $2.23 - $4.16 $3.28 - $5.75 Volatility 54.05% - 63.67% 61.68% - 67.92% Average risk-free interest rate 2.45% - 2.98% 1.40% - 1.94% Dividend yield 0.00% 0.00% Expected term (years) 2.5 - 3.3 2.5 - 5.5
Summary of Activity for Stock Options	The activity for stock options was as follows: 2018 2017 Number of Stock Options Weighted Average Exercise Price Weighted Average Grant Date Fair Value Number of Stock Options Weighted Average Exercise Price Weighted Average Grant Date Fair Value Outstanding at beginning of period 674,470 $ 11.58 $ 6.41 314,303 $ 15.62 $ 9.38 Stock options granted 258,100 $ 8.01 $ 3.43 389,000 $ 8.16 $ 3.89 Stock options exercised (67,083 ) $ 7.89 $ 3.85 (18,500 ) $ 7.91 $ 3.40 Stock options forfeited (135,169 ) $ 9.48 $ 5.18 (1,167 ) $ 15.74 $ 9.60 Stock options expired (108,332 ) $ 13.28 $ 7.58 (9,166 ) $ 17.59 $ 10.77 Outstanding at end of period 621,986 $ 10.66 $ 5.52 674,470 $ 11.58 $ 6.41 Stock options exercisable at end of period 409,914 $ 11.89 $ 6.44 421,960 $ 12.95 $ 7.39 Stock options expected to vest at end of period 212,072 $ 8.27 $ 3.76 252,510 $ 9.28 $ 4.78
Summary of Activity for Restricted Stock Awards	The activity for restricted stock was as follows: For the years ended December 31, 2018 2017 Shares of Restricted Stock Weighted Average Grant Date Fair Value Shares of Restricted Stock Weighted Average Grant Date Fair Value Outstanding at beginning of period 52,502 $ 11.07 94,171 $ 14.29 Restricted stock granted 57,000 $ 7.39 60,000 $ 9.01 Restricted stock vested (42,501 ) $ 10.51 (89,002 ) $ 12.67 Restricted stock forfeited — $ — (12,667 ) $ 13.95 Outstanding at end of period 67,001 $ 8.30 52,502 $ 11.07 Restricted stock expected to vest at end of period 67,001 $ 8.30 52,502 $ 11.07

Income Taxes (Tables)

Income Taxes (Tables)	12 Months Ended
	Dec. 31, 2018
Income Tax Disclosure [Abstract]
Schedule of Loss Before Tax	The components of loss before taxes were as follows: 2018 2017 United States $ (16,262 ) $ (18,064 ) Foreign 3,755 (1,915 ) Loss before income taxes $ (12,507 ) $ (19,979 )
Summary of Income Tax Provision	The provision for income taxes consisted of the following: 2018 2017 Current Deferred Total Current Deferred Total United States $ 18 $ — $ 18 $ — $ — $ — Foreign 142 — 142 37 1 38 Provision for income taxes $ 160 $ — $ 160 $ 37 $ 1 $ 38
Reconciliation of the Provision for Income Taxes	A reconciliation of the provision for income taxes at the United States statutory rate to the effective rate of the Company for the years ended December 31 was as follows: 2018 2017 United States statutory rate (21.0% for 2018 and 34.0% for 2017) $ (2,626 ) $ (6,793 ) Effect of foreign disregarded entity (129 ) (199 ) Taxes on foreign operations 259 35 Net change in valuation allowances 917 8,017 Indebtedness income not subject to income tax — (1,208 ) Effect of intercompany asset transfers — (182 ) Permanent differences and other 1,739 368 Provision for income taxes $ 160 $ 38 Effective tax rate (1.3 )% (0.2 )%
Components of Deferred Income Tax Assets and Liabilities	The components of deferred income tax assets and liabilities consisted of the following at December 31: 2018 2017 Deferred tax assets Accounts receivable $ 46 $ 311 Inventories 1,077 1,024 Accrued expenses and other current liabilities 489 549 Net operating loss carryforwards 24,419 22,864 Tax credit carryforwards 676 676 Other 1,059 1,495 Valuation allowance (26,563 ) (25,690 ) Total deferred tax assets 1,203 1,229 Deferred tax liabilities Property and equipment 703 689 Other 501 541 Total deferred tax liabilities 1,204 1,230 Net deferred tax liabilities (a) $ 1 $ 1 (a) At December 31, 2018 and 2017, net deferred tax liabilities were reflected in other noncurrent liabilities in the consolidated balance sheet.
Summary of Changes to Valuation Allowances	The following table summarizes changes to the Company’s valuation allowances for the years ended December 31: 2018 2017 Balance at beginning of period $ 25,690 $ 25,177 Net increases in allowances 1,247 8,017 Tax Act rate change adjustment — (7,670 ) Foreign currency translation and other adjustments (374 ) 166 Balance at end of period $ 26,563 $ 25,690
Reconciliation of Unrecognized Tax Benefits (Including Accrued Interest and Penalties)	A reconciliation of the beginning and ending amount of unrecognized tax benefits (including accrued interest and penalties) at December 31 was as follows: 2018 2017 Balance at beginning of period $ 1,775 $ 1,217 Additions based on tax positions related to the current year 60 219 Additions for tax positions of prior years — 5 Reductions for tax positions of prior years (606 ) — Settlements — (5 ) Foreign currency translation adjustments (43 ) 339 Balance at end of period $ 1,186 $ 1,775
Summary of Tax Years Subject to Examinations	The following table summarizes tax years remaining subject to examination for each of the Company’s subsidiaries at December 31, 2018: Jurisdiction Tax Years Remaining Subject to Examination United States 2015-2018 Germany 2010-2018 Japan 2017-2018 Italy 2014-2018 Sweden 2015-2017

Fair Value Measurements (Tables

Fair Value Measurements (Tables)	12 Months Ended
	Dec. 31, 2018
Fair Value Disclosures [Abstract]
Carrying Values and Fair Values of Other Financial Instruments	The carrying values and fair values of other financial instruments (assets and liabilities) not required to be recorded at fair value were as follows: December 31, December 31, 2018 2017 Carrying Value Fair Value Carrying Value Fair Value Cash and cash equivalents $ 7,592 $ 7,592 $ 21,848 $ 21,848 Restricted cash $ 1,548 $ 1,548 $ 330 $ 330 Debt issuance costs (a) $ 195 $ — $ — $ — Current portion of long-term debt (b) $ 144 $ 149 $ 137 $ 142 Long-term debt - net of current portion (b) $ 1,364 $ 1,384 $ 1,508 $ 1,533 (a) Represents debt issuance costs associated with the Company’s related party revolving credit facility (Note 14) of which $88 was included in prepaid expenses and other current assets and $107 was included in other noncurrent assets in the accompanying consolidated balance sheet at December 31, 2018 (b) Carrying values at December 31, 2018 and 2017 are net of unamortized debt issuance costs of approximately $20 and $25, respectively.

Other (Income) Expense _ Net (T

Other (Income) Expense – Net (Tables)	12 Months Ended
	Dec. 31, 2018
Other Income And Expenses [Abstract]
Schedule of Other (Income) Expense - Net	Other (income) expense – net consisted of the following: 2018 2017 Gain on settlement of insurance claim $ (819 ) $ (1 ) Interest income (39 ) (56 ) Foreign currency losses – net 93 199 Bank fees 95 122 Other – net (74 ) (61 ) $ (744 ) $ 203

Segment, Product and Geograph_2

Segment, Product and Geographic Information (Tables)	12 Months Ended
	Dec. 31, 2018
Segment Reporting [Abstract]
Revenue by Product	Revenue by product group for the year ended December 31 was as follows: 2018 2017 3D printing machines $ 36,393 $ 29,980 3D printed and other products, materials and services 28,251 27,764 $ 64,644 $ 57,744
Geographic Information for Revenue	Geographic information for revenue for the year ended December 31 was as follows (based on the country where the sale originated): 2018 2017 United States $ 29,514 $ 25,008 Germany 27,084 27,497 Japan 8,027 4,115 Italy (a) 19 917 Sweden (b) — 207 $ 64,644 $ 57,744 (a) In December 2017 the Company committed to a plan to consolidate certain of its 3D printing operations from its Desenzano del Garda, Italy facility into its Gersthofen, Germany facility (Note 5) . Operations at the Desenzano del Garda, Italy facility effectively ceased during the three months ended March 31, 2018 and in December 2018, the Company completed the dissolution of its ExOne Italy S.r.l. subsidiary. (b) In March 2017 the Company terminated its Cooperation Agreement with Swerea SWECAST AB (“Swerea”), resulting in an exit of its PSC/EAC operations in Jönköping, Sweden, effective April 1, 2017. Also in March 2017 the Company agreed to an operating lease agreement with Beijer Industri AB, effective April 1, 2017, related to the 3D printing machine and related equipment located on the Swerea premises, previously covered under the Cooperation Agreement with Swerea
Geographic Information for Long-Lived Assets	Geographic information for long-lived assets at December 31 was as follows (based on the physical location of assets): 2018 2017 United States $ 13,603 $ 14,873 Germany 23,249 25,748 Japan 4,650 4,996 Italy (a) 199 796 Sweden (b) 205 273 United Kingdom (c) — 111 $ 41,906 $ 46,797 (a) In December 2017 the Company committed to a plan to consolidate certain of its 3D printing operations from its Desenzano del Garda, Italy facility into its Gersthofen, Germany facility (Note 5) . Operations at the Desenzano del Garda, Italy facility effectively ceased during the three months ended March 31, 2018 and in December 2018, the Company completed the dissolution of its ExOne Italy S.r.l. subsidiary. At December 31, 2018, long-lived assets represent a 3D printing machine and related equipment held by the Company under an operating lease agreement with a customer. At December 31, 2017, long-lived assets represent certain machinery and other equipment associated with the former Desenzano del Garda facility. (b) At December 31, 2018 and 2017, represents a 3D printing machine and related equipment held by the Company under an operating lease agreement with a customer. (c) At December 31, 2017, represents a 3D printing machine and related equipment held by the Company under an operating lease agreement with a customer. This customer agreement was terminated during 2018.

Summary of Significant Accoun_3

Summary of Significant Accounting Policies - Additional Information (Detail) - USD ($)	Dec. 28, 2018	Dec. 31, 2018	Dec. 31, 2017	Jan. 01, 2019	Jan. 01, 2017
Organization Consolidation And Presentation Of Financial Statements Disclosure [Line Items]
State of incorporation		Delaware
Date of incorporation		Jan. 1, 2013
Recognition of foreign exchange loss	$ 245,000
Current portion of capital leases			$ 15,000
Capital leases – net of current portion			36,000
Maturity of liquid instruments when purchased		three months or less
Allowance for doubtful accounts		$ 225,000	1,193,000
Allowance for doubtful accounts associated net investment in sales-type leases		0	0
Provision (recoveries) for bad debts		58,000	(64,000)
Impairment loss related to held and used assets		$ 0	0
Standard product warranty period		Substantially all of the Company’s 3D printing machine sales are covered by a standard twelve month warranty. Generally, at the time of sale, a liability is recorded (with an offset to cost of sales) based upon the expected cost of replacement parts and labor to be incurred over the life of the standard warranty.
Tax benefits recognized upon settlement		50.00%
Advertising costs		$ 0	0
Percentage of contributions matched		50.00%
Percentage of matching contributions		8.00%
Contributions made to defined contribution savings plan		$ 320,000	$ 303,000
ASU 2016-16 [Member] | Retrospective Adjustment [Member] | Accumulated Deficit [Member]
Organization Consolidation And Presentation Of Financial Statements Disclosure [Line Items]
Cumulative-effect adjustment to accumulated deficit					$ (408,000)
ASU 2016-02 [Member] | Subsequent Events [Member]
Organization Consolidation And Presentation Of Financial Statements Disclosure [Line Items]
Operating lease, right-of-use asset				$ 400,000
Operating lease liability				$ 400,000
Houston, Texas 3D Printing Operations [Member]
Organization Consolidation And Presentation Of Financial Statements Disclosure [Line Items]
Reclassifications of assets held for sale from property and equipment to prepaid and other current assets		$ 822,000
Minimum [Member]
Organization Consolidation And Presentation Of Financial Statements Disclosure [Line Items]
Term till payment is required from date of shipment		30 days
Estimated useful lives		3 years
Maximum [Member]
Organization Consolidation And Presentation Of Financial Statements Disclosure [Line Items]
Term till payment is required from date of shipment		60 days
Estimated useful lives		40 years
Geographic Concentration Risk [Member] | Sales Revenue, Net [Member] | Outside of United States [Member]
Organization Consolidation And Presentation Of Financial Statements Disclosure [Line Items]
Percentage of revenue derived outside the United States		54.30%	56.70%
Subsidiary Guarantors [Member]
Organization Consolidation And Presentation Of Financial Statements Disclosure [Line Items]
Percentage of ownership in subsidiary guarantors		100.00%

Liquidity - Additional Informat

Liquidity - Additional Information (Detail) - USD ($)	Mar. 12, 2018	Mar. 31, 2018	Mar. 31, 2016	Dec. 31, 2018	Dec. 31, 2018	Dec. 31, 2017
Organization Consolidation And Presentation Of Financial Statements Disclosure [Line Items]
Net income (loss)					$ (12,667,000)	$ (20,017,000)
Cash and cash equivalents				$ 7,592,000	7,592,000	$ 21,848,000
Initial And Secondary Public Offerings [Member]
Organization Consolidation And Presentation Of Financial Statements Disclosure [Line Items]
Cumulative unrestricted net proceeds from common stock				168,361,000
FBR Capital Markets & Co. and MLV & Co. LLC [Member] | At Market Issuance Offering [Member]
Organization Consolidation And Presentation Of Financial Statements Disclosure [Line Items]
Unrestricted net proceeds of secondary public offering			$ 595,000
FBR Capital Markets & Co. and MLV & Co. LLC [Member] | At Market Issuance Offering [Member] | Maximum [Member]
Organization Consolidation And Presentation Of Financial Statements Disclosure [Line Items]
Sale of common stock, value			$ 50,000,000
Revolving Credit Facility [Member] | LBM Holdings, LLC [Member]
Organization Consolidation And Presentation Of Financial Statements Disclosure [Line Items]
Credit facility, expiration period	3 years	3 years
Line of credit facility, maximum borrowing capacity		$ 15,000,000		$ 15,000,000	$ 15,000,000

Accumulated Other Comprehensi_3

Accumulated Other Comprehensive Loss - Summary of Changes in the Components of Accumulated Other Comprehensive Loss (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017
Statement Of Income And Comprehensive Income [Abstract]
Balance at beginning of period	$ (9,484)	$ (14,735)
Other comprehensive (loss) income before reclassifications	(1,573)	5,251
Amounts reclassified from accumlated other comprehensive loss	309
Balance at end of period	$ (10,748)	$ (9,484)

Accumulated Other Comprehensi_4

Accumulated Other Comprehensive Loss - Additional Information (Detail) - USD ($)	Dec. 28, 2018	Dec. 31, 2018	Dec. 31, 2017
Accumulated Other Comprehensive Income Loss [Line Items]
Foreign currency translation adjustment in foreign exchange loss recognized with settlement of intercompany note payable	$ 245,000
Accumulated other comprehensive loss, tax		$ 0	$ 0
Amounts reclassified to earnings from accumulated other comprehensive loss		0	$ 0
Dissolution of Related Subsidiary [Member]
Accumulated Other Comprehensive Income Loss [Line Items]
Foreign currency translation adjustment in foreign exchange loss recognized with settlement of intercompany note payable		$ 64,000

Loss Per Share - Additional Inf

Loss Per Share - Additional Information (Detail) - shares	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017
Stock Option [Member]
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Potential shares of anti-dilutive common stock	621,986	674,470
Restricted Stock [Member]
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Potential shares of anti-dilutive common stock	67,001	52,502

Loss Per Share - Computation of

Loss Per Share - Computation of Basic and Diluted Loss Per Common Share (Detail) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017
Earnings Per Share [Abstract]
Net loss	$ (12,667)	$ (20,017)
Weighted average shares outstanding (basic and diluted)	16,176,415	16,062,424
Net loss per common share:
Basic	$ (0.78)	$ (1.25)
Diluted	$ (0.78)	$ (1.25)

Restructuring - Additional Info

Restructuring - Additional Information (Detail) - USD ($)	May 09, 2017	Apr. 21, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2018	Dec. 31, 2017
Restructuring Cost And Reserve [Line Items]
Gain (loss) on disposal of assets					$ 51,000	$ 325,000
Proceeds from sale of property and equipment					98,000	3,706,000
Houston, Texas 3D Printing Operations [Member]
Restructuring Cost And Reserve [Line Items]
Involuntary employee terminations charges					28,000
Asset impairment charges					1,000
Additional charges expected to be incurred					0
Houston, Texas 3D Printing Operations [Member] | Cost of Sales [Member]
Restructuring Cost And Reserve [Line Items]
Involuntary employee terminations charges					15,000
Houston, Texas 3D Printing Operations [Member] | Selling, General and Administrative Expenses [Member]
Restructuring Cost And Reserve [Line Items]
Involuntary employee terminations charges					13,000
Desenzano Del Garada, Italy 3D Printing Operations [Member]
Restructuring Cost And Reserve [Line Items]
Involuntary employee terminations charges						72,000
Asset impairment charges					241,000
Additional charges expected to be incurred					0
Total restructuring charges					258,000
Other exit costs					17,000
Gain (loss) on disposal of assets					$ 51,000
Desenzano Del Garada, Italy 3D Printing Operations [Member] | Cost of Sales [Member]
Restructuring Cost And Reserve [Line Items]
Involuntary employee terminations charges						19,000
Desenzano Del Garada, Italy 3D Printing Operations [Member] | Selling, General and Administrative Expenses [Member]
Restructuring Cost And Reserve [Line Items]
Involuntary employee terminations charges						53,000
North Las Vegas, Nevada 3D Printing Operations [Member]
Restructuring Cost And Reserve [Line Items]
Involuntary employee terminations charges						142,000
Asset impairment charges						867,000
Additional charges expected to be incurred						0
Total restructuring charges						1,016,000
Other exit costs						7,000
North Las Vegas, Nevada 3D Printing Operations [Member] | Cost of Sales [Member]
Restructuring Cost And Reserve [Line Items]
Asset impairment charges						598,000
North Las Vegas, Nevada 3D Printing Operations [Member] | Selling, General and Administrative Expenses [Member]
Restructuring Cost And Reserve [Line Items]
Asset impairment charges						269,000
Chesterfield Michigan Non Core Specialty Machining Operations [Member]
Restructuring Cost And Reserve [Line Items]
Gain (loss) on disposal of assets			$ (42,000)
Proceeds from sale of inventories		$ 79,000
Proceeds from sale of property and equipment		2,475,000
Proceeds from sale of other contractual rights		269,000
Gross proceeds from the sale assets		2,050,000
Impairment loss				$ 859,000		269,000
Chesterfield Michigan Non Core Specialty Machining Operations [Member] | Service [Member]
Restructuring Cost And Reserve [Line Items]
Direct cost of assets		$ 128,000
Chesterfield Michigan Non Core Specialty Machining Operations [Member] | Property Plant and Equipment [Member]
Restructuring Cost And Reserve [Line Items]
Impairment loss				590,000
Chesterfield Michigan Non Core Specialty Machining Operations [Member] | Intangible Assets [Member]
Restructuring Cost And Reserve [Line Items]
Impairment loss				$ 269,000
North Las Vegas, Nevada [Member]
Restructuring Cost And Reserve [Line Items]
Gain (loss) on disposal of assets	$ 137,000
Proceeds from sale of property and equipment	1,950,000
North Las Vegas, Nevada [Member] | Service [Member]
Restructuring Cost And Reserve [Line Items]
Direct cost of assets	$ 347,000
North Las Vegas, Nevada [Member] | Property Plant and Equipment [Member]
Restructuring Cost And Reserve [Line Items]
Gain (loss) on disposal of assets						$ (8,000)

Impairment - Additional Informa

Impairment - Additional Information (Detail)	3 Months Ended
	Dec. 31, 2018USD ($)Asset_Group
Asset Impairment Charges [Abstract]
Number of operating asset groups | Asset_Group	3
Long-lived assets held for use impairment loss | $	$ 0

Cash, Cash Equivalents, and R_3

Cash, Cash Equivalents, and Restricted Cash - Schedule of Reconciliation of Cash, Cash Equivalents, and Restricted Cash (Detail) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Cash And Cash Equivalents [Abstract]
Cash and cash equivalents	$ 7,592	$ 21,848
Restricted cash	1,548	330
Total cash, cash equivalents, and restricted cash shown in the statement of consolidated cash flows	$ 9,140	$ 22,178

Cash, Cash Equivalents, and R_4

Cash, Cash Equivalents, and Restricted Cash - Additional Information (Detail) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Cash Cash Equivalents And Restricted Cash [Line Items]
Restricted cash associated with cash collateral	$ 1,548	$ 330
German Bank [Member]
Cash Cash Equivalents And Restricted Cash [Line Items]
Restricted cash associated with cash collateral	1,044
United States Bank [Member]
Cash Cash Equivalents And Restricted Cash [Line Items]
Restricted cash associated with cash collateral	$ 504	$ 330

Inventories - Schedule of Inven

Inventories - Schedule of Inventories (Detail) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Inventory Disclosure [Abstract]
Raw materials and components	$ 7,747	$ 7,171
Work in process	5,147	4,630
Finished goods	3,036	3,629
Inventories	$ 15,930	$ 15,430

Inventories - Additional Inform

Inventories - Additional Information (Detail) - USD ($) $ in Thousands	3 Months Ended		12 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Dec. 31, 2018	Dec. 31, 2017
Inventory [Line Items]
Allowance for slow-moving and obsolete inventories			$ 4,143	$ 3,437
Inventory (credit) charge			$ 29	$ 271
Auburn, Washington 3D Printing Operations [Member]
Inventory [Line Items]
Inventory (credit) charge		$ 1,460
Industrial Microwave [Member]
Inventory [Line Items]
Inventory (credit) charge	$ 561

Long-Lived Assets - Summary of

Long-Lived Assets - Summary of Property and Equipment (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017
Property, Plant and Equipment [Line Items]
Total gross property and equipment before accumulated depreciation	$ 60,707	$ 63,796
Less: Accumulated depreciation	(19,306)	(17,739)
Property and equipment, excluding construction-in-progress	41,401	46,057
Construction-in-progress	505	740
Property and equipment - net	$ 41,906	46,797
Minimum [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, Economic Life	3 years
Maximum [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, Economic Life	40 years
Land [Member]
Property, Plant and Equipment [Line Items]
Total gross property and equipment before accumulated depreciation	$ 7,024	7,205
Building and Related Improvements [Member]
Property, Plant and Equipment [Line Items]
Total gross property and equipment before accumulated depreciation	$ 25,895	27,785
Building and Related Improvements [Member] | Minimum [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, Economic Life	5 years
Building and Related Improvements [Member] | Maximum [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, Economic Life	40 years
Machinery and Equipment [Member]
Property, Plant and Equipment [Line Items]
Total gross property and equipment before accumulated depreciation	$ 20,667	22,034
Machinery and Equipment [Member] | Minimum [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, Economic Life	3 years
Machinery and Equipment [Member] | Maximum [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, Economic Life	20 years
Other [Member]
Property, Plant and Equipment [Line Items]
Total gross property and equipment before accumulated depreciation	$ 7,121	$ 6,772
Other [Member] | Minimum [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, Economic Life	3 years
Other [Member] | Maximum [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, Economic Life	20 years

Long-Lived Assets - Additional

Long-Lived Assets - Additional Information (Detail) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
	Mar. 31, 2017	Dec. 31, 2018	Dec. 31, 2017
Long-Lived Assets [Line Items]
Depreciation		$ 5,439	$ 5,637
Amortization of intangible assets		64	641
North Las Vegas, Nevada 3D Printing Operations [Member]
Long-Lived Assets [Line Items]
Asset impairment charges			598
Chesterfield Michigan Non Core Specialty Machining Operations [Member]
Long-Lived Assets [Line Items]
Impairment loss	$ 859		269
Machinery and Equipment [Member]
Long-Lived Assets [Line Items]
Machinery and equipment		101	85
Machinery and equipment		2,345	2,254
Carrying value of assets		$ 1,264	$ 1,620

Long-Lived Assets - Schedule of

Long-Lived Assets - Schedule of Minimum Future Rentals of Machinery and Equipment Under Non-cancellable Arrangements (Detail) - Machinery and Equipment [Member] $ in Thousands	Dec. 31, 2018USD ($)
Property, Plant and Equipment [Line Items]
2019	$ 687
2020	148
2021	48
2022	0
2023	0
Thereafter	0
Minimum future rentals of machinery and equipment, total	$ 883

Long-Lived Assets - Schedule _2

Long-Lived Assets - Schedule of Intangible Assets (Detail) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Finite Lived Intangible Assets [Line Items]
Gross Carrying Amount	$ 1,418	$ 1,484
Accumulated Amortization	(1,418)	(1,422)
Finite lived intangible asset net		62
Unpatented Technology [Member]
Finite Lived Intangible Assets [Line Items]
Gross Carrying Amount	1,388	1,453
Accumulated Amortization	(1,388)	(1,392)
Finite lived intangible asset net		61
Trade Names [Member]
Finite Lived Intangible Assets [Line Items]
Gross Carrying Amount	30	31
Accumulated Amortization	$ (30)	(30)
Finite lived intangible asset net		$ 1

Net Investment in Sales-Type _3

Net Investment in Sales-Type Leases - Schedule of Net Investment in Sales-Type Leases (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Leases [Abstract]
Future minimum lease payments receivable	$ 1,969	$ 1,100
Less: Unearned interest income	(316)	(159)
Net investment in sales-type leases	$ 1,653	$ 941

Net Investment in Sales-Type _4

Net Investment in Sales-Type Leases - Additional Information (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017
Capital Leased Assets [Line Items]
Net investment in sales-type leases	$ (1,653)	$ (941)
Interest income associated with sales-type leases	48	28
Accounts Receivable [Member]
Capital Leased Assets [Line Items]
Net investment in sales-type leases	(302)	(205)
Other Noncurrent Assets [Member]
Capital Leased Assets [Line Items]
Net investment in sales-type leases	$ (1,351)	$ (736)

Net Investment in Sales-Type _5

Net Investment in Sales-Type Leases - Schedule of Future Minimum Lease Payments Due from Customers Under Sales-Type Leases (Details) $ in Thousands	Dec. 31, 2018USD ($)
Leases [Abstract]
2019	$ 409
2020	382
2021	382
2022	382
2023	414
Total	$ 1,969

Accrued Expenses and Other Cu_3

Accrued Expenses and Other Current Liabilities - Schedule of Accrued Expenses and Other Current Liabilities (Detail) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Payables And Accruals [Abstract]
Accrued payroll and related costs	$ 1,895	$ 2,044
Product warranty reserves	1,670	1,300
Liability for uncertain tax positions	820	858
Accrued license fees	721	397
Accrued professional fees	215	223
Value-added taxes payable	140	28
Accrued sales commissions	123	307
Accrued property taxes	108	99
Income taxes payable	90	32
Other	267	808
Accrued expenses and other current liabilities	$ 6,049	$ 6,096

Product Warranty Reserves - Sum

Product Warranty Reserves - Summary of Changes in Product Warranty Reserves (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017
Guarantees [Abstract]
Balance at beginning of period	$ 1,300	$ 1,115
Provisions for new issuances	1,803	1,288
Payments	(960)	(701)
Reserve adjustments	(434)	(500)
Foreign currency translation adjustments	(39)	98
Balance at end of period	$ 1,670	$ 1,300

Contingencies and Commitments -

Contingencies and Commitments - Additional Information (Detail) € in Thousands	Jul. 01, 2017USD ($)	Sep. 30, 2017USD ($)	Dec. 31, 2018USD ($)	Dec. 31, 2017USD ($)	Dec. 31, 2018EUR (€)	Dec. 31, 2017EUR (€)
Line Of Credit Facility [Line Items]
Revenue associated with Sales Agreement net of the cash payment			$ 64,644,000	$ 57,744,000
Lease expiration year			2026
Rent expense under operating lease			$ 235,000	358,000
Germany [Member]
Line Of Credit Facility [Line Items]
Revenue associated with Sales Agreement net of the cash payment			27,084,000	27,497,000
German Bank [Member] | Germany [Member]
Line Of Credit Facility [Line Items]
Line of credit facility, maximum borrowing capacity			1,400,000		€ 1,300
Credit facility, minimum increments			100,000		100
Credit facility, commitment fee			$ 0
German Bank [Member] | Germany [Member] | Minimum [Member]
Line Of Credit Facility [Line Items]
Debt Instrument, term			30 days
German Bank [Member] | Germany [Member] | Commercial Transactions Requiring Security [Member]
Line Of Credit Facility [Line Items]
Credit facility, interest rate			1.75%
Credit facility, outstanding amount				1,128,000		€ 941
German Bank [Member] | Germany [Member] | Commercial Transactions Requiring Security [Member] | Separate Agreements for Additional Capacity for Financial Guarantees and Letters of Credit [Member]
Line Of Credit Facility [Line Items]
Credit facility, outstanding amount			$ 96,000		80
Expiration date, description			June 2022
German Bank [Member] | Germany [Member] | Overdraft Credit [Member]
Line Of Credit Facility [Line Items]
Credit facility, interest rate			10.20%
Outstanding borrowings in form of overdraft credit or short-term loans			$ 0	0
German Bank [Member] | Germany [Member] | Short-Term Loans [Member]
Line Of Credit Facility [Line Items]
Outstanding borrowings in form of overdraft credit or short-term loans			0	$ 0
German Bank [Member] | Germany [Member] | Commercial Transactions Requiring Security Expiring From March 2019 Through November 2019 [Member]
Line Of Credit Facility [Line Items]
Credit facility, outstanding amount			$ 1,044,000		€ 912
Expiration date, description			March 2019 through November 2019
Kocel [Member]
Line Of Credit Facility [Line Items]
Settlement Agreement date			July 1, 2017
Settlement Agreement, counterparty's name			Kocel Foundry Limited (also known as Kocel CSR Casting Company, Limited) and Kocel Group (Hong Kong) Limited (collectively, “Kocel”)
Cash payment relates to Sales Agreement	$ 811,000
Revenue associated with Sales Agreement net of the cash payment		$ 2,762,000

Contingencies and Commitments_2

Contingencies and Commitments - Future Minimum Lease Payments of Operating Lease Arrangements (Detail) $ in Thousands	Dec. 31, 2018USD ($)
Commitments And Contingencies Disclosure [Abstract]
2019	$ 170
2020	111
2021	76
2022	67
2023	12
Thereafter	5
Future minimum lease payments of operating lease, Total	$ 441

Related Party Revolving Credi_2

Related Party Revolving Credit Facility - Additional Information (Detail) - USD ($)	Mar. 12, 2018	Mar. 31, 2018	Dec. 31, 2018	Dec. 31, 2017
Related Party Transaction [Line Items]
Amortization of debt issuance costs			$ 75,000	$ 6,000
Accounts payable			4,376,000	$ 4,291,000
Revolving Credit Facility [Member] | Prepaid Expenses and Other Current Assets [Member]
Related Party Transaction [Line Items]
Debt issuance costs, net			88,000
Revolving Credit Facility [Member] | Other Noncurrent Assets [Member]
Related Party Transaction [Line Items]
Debt issuance costs, net			107,000
Revolving Credit Facility [Member] | LBM Holdings, LLC [Member]
Related Party Transaction [Line Items]
Line of credit facility, maximum borrowing capacity		$ 15,000,000	$ 15,000,000
Credit facility, expiration period	3 years	3 years
Credit facility, expiration date	Mar. 12, 2021
Credit facility, description of variable rate basis	one month LIBOR
Credit facility, interest rate	6.70%		7.50%
Credit facility, commitment fee on unused portion, percentage	0.75%
Credit facility, commitment fee on unused portion, payable term	The LBM Credit Agreement requires a commitment fee of 75 basis points, or 0.75%, on the unused portion of the facility, payable monthly in arrears.
Credit facility, up-front commitment fee percentage	1.25%
Credit facility, up-front commitment fee amount	$ 188,000
Credit facility, minimum increments	1,000,000
Available loan proceeds deposited into escrow account	$ 15,000,000
Credit facility, outstanding amount			$ 0
Debt issuance costs			265,000
Interest expense relating to the Credit Agreement			160,000
Amortization of debt issuance costs			70,000
Debt issuance costs, net			195,000
Interest expense relating to the commitment fee			90,000
Accounts payable			10,000
Revolving Credit Facility [Member] | LBM Holdings, LLC [Member] | Prepaid Expenses and Other Current Assets [Member]
Related Party Transaction [Line Items]
Debt issuance costs, net			88,000
Revolving Credit Facility [Member] | LBM Holdings, LLC [Member] | Other Noncurrent Assets [Member]
Related Party Transaction [Line Items]
Debt issuance costs, net			$ 107,000
Revolving Credit Facility [Member] | One Month LIBOR [Member] | LBM Holdings, LLC [Member]
Related Party Transaction [Line Items]
Credit facility, basis spread on variable rate	5.00%

Long-Term Debt - Components of

Long-Term Debt - Components of Long-Term Debt (Detail) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Debt Disclosure [Abstract]
Building note payable, Principal	$ 1,533	$ 1,675
Less: amount due within one year, Principal	(149)	(142)
Long-term debt - net of current portion, Principal	1,384	1,533
Building note payable, Unamortized Debt Issuance Costs	(25)	(30)
Less: amount due within one year, Unamortized Debt Issuance Costs	5	5
Long-term debt - net of current portion, Unamortized Debt Issuance Costs	(20)	(25)
Building note payable, Net	1,508	1,645
Less: amount due within one year, Net	(144)	(137)
Long-term debt - net of current portion	$ 1,364	$ 1,508

Long-Term Debt - Additional Inf

Long-Term Debt - Additional Information (Detail) - Building Note Payable [Member] $ in Thousands	12 Months Ended
	Dec. 31, 2018USD ($)
Debt Instrument [Line Items]
Notes payable monthly payments	$ 18
Building note payable, with monthly payments interest rate	4.00%
Building note payable, with monthly payments basis spread	3.25%
Date of interest rate adjustment	2017-05
Notes payable maturity	2027-05
Building [Member] | North Huntington, Pennsylvania [Member]
Debt Instrument [Line Items]
Carrying value of collateralized facility	$ 5,128
United States Treasury Securities [Member]
Debt Instrument [Line Items]
Notes payable monthly payments	$ 19

Long-Term Debt - Future Maturit

Long-Term Debt - Future Maturities of Long-Term Debt (Detail) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Debt Disclosure [Abstract]
2019	$ 149
2020	157
2021	166
2022	173
2023	182
Thereafter	706
Building note payable, Principal	$ 1,533	$ 1,675

Equity-Based Compensation - Add

Equity-Based Compensation - Additional Information (Detail) - USD ($)	Jan. 24, 2013	Dec. 31, 2018	Dec. 31, 2017
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation expense		$ 968,000	$ 2,456,000
Weighted-average remaining vesting period		1 year 2 months 12 days
Proceeds from exercise of employee stock options		$ 529,000	147,000
Stock Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation expense		357,000	1,503,000
Total future compensation expense		682,000
Intrinsic value, stock options expected to vest		0
Intrinsic value, stock options exercisable		$ 3,000
Weighted average remaining contractual term of stock options exercisable		4 years 8 months 12 days
Weighted average remaining contractual term of stock options expected to vest		4 years 10 months 24 days
Intrinsic value of stock options exercised		$ 586,000	218,000
Proceeds from exercise of employee stock options		529,000	147,000
Income tax benefit		0	0
Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation expense		433,000	953,000
Total future compensation expense		273,000
Fair value of restricted shares vested		$ 326,000	$ 801,000
Maximum [Member] | Stock Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period		3 years
Stock options contractual expiration period		10 years
Maximum [Member] | Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period		3 years
Minimum [Member] | Stock Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period		1 year
Stock options contractual expiration period		5 years
Minimum [Member] | Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period		1 year
2013 Equity Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock reserved for issuance	500,000
Remaining shares available for future issuance		1,024,185
2013 Equity Incentive Plan [Member] | Common Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of outstanding shares of common stock	3.00%
2013 Equity Incentive Plan [Member] | Common Stock [Member] | Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of Shares authorized	1,992,241
2018 Annual Incentive Program [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Target amount payable under Program		$ 1,423,000
Compensation expense		460,000
Compensation expense, expected to be settled in equity		167,000
2018 Annual Incentive Program [Member] | Cost of Sales [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation expense		91,000
2018 Annual Incentive Program [Member] | Research and Development [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation expense		127,000
2018 Annual Incentive Program [Member] | Selling, General and Administrative Expenses [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation expense		$ 242,000

Equity-Based Compensation - Sum

Equity-Based Compensation - Summary of Equity-Based Compensation Expense (Detail) - USD ($) $ in Thousands		12 Months Ended
		Dec. 31, 2018	Dec. 31, 2017
Equity-based compensation expense recognized:
Total equity-based compensation expense before income taxes		$ 968	$ 2,456
Benefit for income taxes	[1]	0	0
Total equity-based compensation expense net of income taxes		968	2,456
Stock Options [Member]
Equity-based compensation expense recognized:
Total equity-based compensation expense before income taxes		357	1,503
Restricted Stock [Member]
Equity-based compensation expense recognized:
Total equity-based compensation expense before income taxes		433	953
Other [Member]
Equity-based compensation expense recognized:
Total equity-based compensation expense before income taxes	[2]	$ 178	$ 0
[1]	The benefit for income taxes from equity-based compensation for each of the periods presented has been determined to be $0 based on valuation allowances against net deferred tax assets.
[2]	Other represents expense associated with the Program and other employee contractual amounts to be settled in equity.

Equity-Based Compensation - S_2

Equity-Based Compensation - Summary of Equity-Based Compensation Expense (Parenthetical) (Detail) - USD ($) $ in Thousands		12 Months Ended
		Dec. 31, 2018	Dec. 31, 2017
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Benefit for income taxes from equity-based compensation	[1]	$ 0	$ 0
[1]	The benefit for income taxes from equity-based compensation for each of the periods presented has been determined to be $0 based on valuation allowances against net deferred tax assets.

Equity-Based Compensation - Ass

Equity-Based Compensation - Assumptions for Fair Value of Stock Options Granted Estimated on the Date of Grant Using the Black-Scholes Option (Detail) - Stock Options [Member] - $ / shares	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Dividend yield	0.00%	0.00%
Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted average fair value per stock option	$ 2.23	$ 3.28
Volatility	54.05%	61.68%
Average risk-free interest rate	2.45%	1.40%
Expected term (years)	2 years 6 months	2 years 6 months
Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted average fair value per stock option	$ 4.16	$ 5.75
Volatility	63.67%	67.92%
Average risk-free interest rate	2.98%	1.94%
Expected term (years)	3 years 3 months 18 days	5 years 6 months

Equity-Based Compensation - S_3

Equity-Based Compensation - Summary of Activity for Stock Options (Detail) - $ / shares	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Stock options outstanding, Beginning balance	674,470	314,303
Stock options granted	258,100	389,000
Stock options exercised	(67,083)	(18,500)
Stock options forfeited	(135,169)	(1,167)
Stock options expired	(108,332)	(9,166)
Stock options outstanding, Ending balance	621,986	674,470
Stock options exercisable at end of period	409,914	421,960
Stock options expected to vest at end of period	212,072	252,510
Weighted average exercise price, Beginning balance	$ 11.58	$ 15.62
Weighted average exercise price, Stock options granted	8.01	8.16
Weighted average exercise price, Stock options exercised	7.89	7.91
Weighted average exercise price, Stock options forfeited	9.48	15.74
Weighted average exercise price, Stock options expired	13.28	17.59
Weighted average exercise price, Ending balance	10.66	11.58
Weighted average exercise price, Stock options exercisable	11.89	12.95
Weighted average exercise price, Stock options expected to vest, net of forfeitures	8.27	9.28
Weighted average grant date fair value, Beginning balance	6.41	9.38
Weighted average grant date fair value, Stock options granted	3.43	3.89
Weighted average grant date fair value, Stock options exercised	3.85	3.40
Weighted average grant date fair value, Stock options forfeited	5.18	9.60
Weighted average grant date fair value, Stock options expired	7.58	10.77
Weighted average grant date fair value, Ending balance	5.52	6.41
Weighted average grant date fair value, Stock options exercisable	6.44	7.39
Weighted average grant date fair value, Stock options expected to vest, net of forfeitures	$ 3.76	$ 4.78

Equity-Based Compensation - S_4

Equity-Based Compensation - Summary of Activity for Restricted Stock Awards (Detail) - Restricted Stock [Member] - $ / shares	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of Restricted Shares, outstanding, Beginning Balance	52,502	94,171
Number of Restricted Shares, granted	57,000	60,000
Number of Restricted Shares, vested	(42,501)	(89,002)
Number of Restricted Shares, forfeited	0	(12,667)
Number of Restricted Shares, outstanding, Ending Balance	67,001	52,502
Number of Restricted Shares, expected to vest	67,001	52,502
Weighted Average Grant Date Fair Value, Beginning Balance	$ 11.07	$ 14.29
Weighted Average Grant Date Fair Value, granted	7.39	9.01
Weighted Average Grant Date Fair Value, vested	10.51	12.67
Weighted Average Grant Date Fair Value, forfeited	0	13.95
Weighted Average Grant Date Fair Value, Ending Balance	8.30	11.07
Weighted Average Grant Date Fair Value, expected to vest	$ 8.30	$ 11.07

Income Taxes - Schedule of Loss

Income Taxes - Schedule of Loss Before Tax (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017
Income Tax Disclosure [Abstract]
United States	$ (16,262)	$ (18,064)
Foreign	3,755	(1,915)
Loss before income taxes	$ (12,507)	$ (19,979)

Income Taxes - Summary of Incom

Income Taxes - Summary of Income Tax Provision (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017
Income Tax Disclosure [Abstract]
United States	$ 18
Foreign	142	$ 37
Provision for income taxes	160	37
Foreign		1
Provision for income taxes		1
United States	18
Foreign	142	38
Provision for income taxes	$ 160	$ 38

Income Taxes - Reconciliation o

Income Taxes - Reconciliation of the Provision for Income Taxes (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017
Income Tax Disclosure [Abstract]
United States statutory rate (21.0% for 2018 and 34.0% for 2017)	$ (2,626)	$ (6,793)
Effect of foreign disregarded entity	(129)	(199)
Taxes on foreign operations	259	35
Net change in valuation allowances	917	8,017
Indebtedness income not subject to income tax		(1,208)
Effect of intercompany asset transfers		(182)
Permanent differences and other	1,739	368
Provision for income taxes	$ 160	$ 38
Effective tax rate	(1.30%)	(0.20%)

Income Taxes - Reconciliation_2

Income Taxes - Reconciliation of the Provision for Income Taxes (Parenthetical) (Detail)	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017
Income Tax Disclosure [Abstract]
United States statutory rate	21.00%	34.00%

Income Taxes - Additional Infor

Income Taxes - Additional Information (Detail) - USD ($)	3 Months Ended	12 Months Ended
	Mar. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Schedule Of Income Taxes [Line Items]
United States statutory rate		21.00%	34.00%
Tax Cuts and Jobs Act, accounting complete		true
Penalties and interest expense		$ 0	$ 0
Unrecognized tax benefits including accrued interest and penalties		820,000	$ 858,000
Subsidiaries [Member] | United States [Member]
Schedule Of Income Taxes [Line Items]
Net operating loss carryforwards		85,674,000
Net operating loss carryforwards subject to expire		70,100,000
Net operating loss carryforwards not subject to expire		15,574,000
Subsidiaries [Member] | Japan [Member]
Schedule Of Income Taxes [Line Items]
Net operating loss carryforwards		3,162,000
Subsidiaries [Member] | Germany [Member]
Schedule Of Income Taxes [Line Items]
Net operating loss carryforwards		$ 18,303,000
Subsidiaries [Member] | Germany [Member] | Scenario, Forecast [Member] | Local Taxing Authorities [Member]
Schedule Of Income Taxes [Line Items]
Reversal of previously recorded liabilities for uncertain tax positions	$ 1,187,000
Uncertain tax positions expected amount to be offset against net operating loss carryforwards	367,000
Income tax benefit recorded from uncertain tax positions	$ 820,000
Subsidiaries [Member] | Earliest Tax Year [Member] | United States [Member]
Schedule Of Income Taxes [Line Items]
Expiration period of net operating loss carryforwards		2033
Subsidiaries [Member] | Earliest Tax Year [Member] | Japan [Member]
Schedule Of Income Taxes [Line Items]
Expiration period of net operating loss carryforwards		2019
Subsidiaries [Member] | Latest Tax Year [Member] | United States [Member]
Schedule Of Income Taxes [Line Items]
Expiration period of net operating loss carryforwards		2037
Subsidiaries [Member] | Latest Tax Year [Member] | Japan [Member]
Schedule Of Income Taxes [Line Items]
Expiration period of net operating loss carryforwards		2026
Subsidiaries [Member] | 2023 [Member] | United States [Member]
Schedule Of Income Taxes [Line Items]
Tax credit carryforwards		$ 676,000
Expiration period of tax credit carryforwards		2023

Income Taxes - Components of De

Income Taxes - Components of Deferred Income Tax Assets and Liabilities (Detail) - USD ($) $ in Thousands		Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Deferred tax assets
Accounts receivable		$ 46	$ 311
Inventories		1,077	1,024
Accrued expenses and other current liabilities		489	549
Net operating loss carryforwards		24,419	22,864
Tax credit carryforwards		676	676
Other		1,059	1,495
Valuation allowance		(26,563)	(25,690)	$ (25,177)
Total deferred tax assets		1,203	1,229
Deferred tax liabilities
Property and equipment		703	689
Other		501	541
Total deferred tax liabilities		1,204	1,230
Net deferred tax liabilities	[1]	$ 1	$ 1
[1]	At December 31, 2018 and 2017, net deferred tax liabilities were reflected in other noncurrent liabilities in the consolidated balance sheet.

Income Taxes - Summary of Chang

Income Taxes - Summary of Changes to Valuation Allowances (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017
Income Tax Disclosure [Abstract]
Balance at beginning of period	$ 25,690	$ 25,177
Net increases in allowances	1,247	8,017
Tax Act rate change adjustment		(7,670)
Foreign currency translation and other adjustments	(374)	166
Balance at end of period	$ 26,563	$ 25,690

Income Taxes - Reconciliation_3

Income Taxes - Reconciliation of Unrecognized Tax Benefits (Including Accrued Interest and Penalties) (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017
Income Tax Disclosure [Abstract]
Balance at beginning of period	$ 1,775	$ 1,217
Additions based on tax positions related to the current year	60	219
Additions for tax positions of prior years		5
Reductions for tax positions of prior years	(606)
Settlements		(5)
Foreign currency translation adjustments	(43)	339
Balance at end of period	$ 1,186	$ 1,775

Income Taxes - Summary of Tax Y

Income Taxes - Summary of Tax Year Subject to Examinations (Detail)	12 Months Ended
	Dec. 31, 2018
United States [Member] | Earliest Tax Year [Member]
Income Tax Contingency [Line Items]
Tax year subject to examination	2015
United States [Member] | Latest Tax Year [Member]
Income Tax Contingency [Line Items]
Tax year subject to examination	2018
Germany [Member] | Earliest Tax Year [Member]
Income Tax Contingency [Line Items]
Tax year subject to examination	2010
Germany [Member] | Latest Tax Year [Member]
Income Tax Contingency [Line Items]
Tax year subject to examination	2018
Japan [Member] | Earliest Tax Year [Member]
Income Tax Contingency [Line Items]
Tax year subject to examination	2017
Japan [Member] | Latest Tax Year [Member]
Income Tax Contingency [Line Items]
Tax year subject to examination	2018
Italy [Member] | Earliest Tax Year [Member]
Income Tax Contingency [Line Items]
Tax year subject to examination	2014
Italy [Member] | Latest Tax Year [Member]
Income Tax Contingency [Line Items]
Tax year subject to examination	2018
Sweden [Member] | Earliest Tax Year [Member]
Income Tax Contingency [Line Items]
Tax year subject to examination	2015
Sweden [Member] | Latest Tax Year [Member]
Income Tax Contingency [Line Items]
Tax year subject to examination	2017

Fair Value Measurements - Addit

Fair Value Measurements - Additional Information (Detail) - Level 2 Fair Value Measurements [Member] - German Bank [Member] € in Thousands, $ in Thousands	1 Months Ended		3 Months Ended
	Aug. 31, 2017USD ($)	Aug. 31, 2017EUR (€)	Mar. 31, 2017USD ($)Contract	Mar. 31, 2017EUR (€)Contract
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Number of foreign exchange forward contracts			2	2
Gain realized on settlement of foreign exchange forward contracts	$ 14	€ 12	$ 16	€ 15

Fair Value Measurements - Carry

Fair Value Measurements - Carrying Values and Fair Values of Other Financial Instruments (Detail) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Carrying Value [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and cash equivalents	$ 7,592	$ 21,848
Restricted cash	1,548	330
Debt issuance costs	195
Current portion of long-term debt	144	137
Long-term debt ̶ net of current portion	1,364	1,508
Fair Value [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and cash equivalents	7,592	21,848
Restricted cash	1,548	330
Current portion of long-term debt	149	142
Long-term debt ̶ net of current portion	$ 1,384	$ 1,533

Fair Value Measurements - Car_2

Fair Value Measurements - Carrying Values and Fair Values of Other Financial Instruments (Parenthetical) (Detail) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Unamortized debt issuance costs	$ 20	$ 25
Revolving Credit Facility [Member] | Prepaid Expenses and Other Current Assets [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Debt issuance costs	88
Revolving Credit Facility [Member] | Other Noncurrent Assets [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Debt issuance costs	$ 107

Concentration of Credit Risk -

Concentration of Credit Risk - Additional Information (Detail) - Five Most Significant Customers [Member] - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017
Revenue, Major Customer [Line Items]
Accounts receivable from significant customers	$ 2,344	$ 4,199
Customer Concentration Risk [Member] | Sales Revenue, Net [Member]
Revenue, Major Customer [Line Items]
Revenue concentration, by most significant customers	16.50%	20.50%

Related Party Transactions - Ad

Related Party Transactions - Additional Information (Detail) - USD ($)	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017
Related Party Transaction [Line Items]
Revenue - related parties	$ 0	$ 33,000
Amounts due from related parties reflected in accounts receivable	0	0
Accounts Payable [Member]
Related Party Transaction [Line Items]
Amounts due to related party	1,000	1,000
Former Chairman and Chief Executive Officer [Member]
Related Party Transaction [Line Items]
Purchases from related parties	27,000	14,000
Fair market value of benefits received from related party	$ 8,000	$ 0

Other (Income) Expense - Net -

Other (Income) Expense - Net - Schedule of Other (Income) Expense - Net (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017
Other Income And Expenses [Abstract]
Gain on settlement of insurance claim	$ (819)	$ (1)
Interest income	(39)	(56)
Foreign currency losses – net	93	199
Bank fees	95	122
Other – net	(74)	(61)
Other (income) expense – net	$ (744)	$ 203

Other (Income) Expense - Net _2

Other (Income) Expense - Net - Additional Information (Detail) - USD ($) $ in Thousands	Dec. 28, 2018	Dec. 31, 2018	Dec. 31, 2017
Other Income Expense Net [Line Items]
Realized gain associated with insurance recovery		$ 819	$ 1
Foreign currency translation adjustment in foreign exchange loss recognized with settlement of intercompany note payable	$ 245
3D Printing Machines [Member]
Other Income Expense Net [Line Items]
Realized gain associated with insurance recovery		$ 819

Segment, Product and Geograph_3

Segment, Product and Geographic Information - Revenue by Product (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017
Revenue from External Customer [Line Items]
Revenues	$ 64,644	$ 57,744
3D Printing Machines [Member]
Revenue from External Customer [Line Items]
Revenues	36,393	29,980
3D Printed and Other Products, Materials and Services [Member]
Revenue from External Customer [Line Items]
Revenues	$ 28,251	$ 27,764

Segment, Product and Geograph_4

Segment, Product and Geographic Information - Geographic Information for Revenue (Detail) - USD ($) $ in Thousands		12 Months Ended
		Dec. 31, 2018	Dec. 31, 2017
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenues		$ 64,644	$ 57,744
United States [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenues		29,514	25,008
Germany [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenues		27,084	27,497
Japan [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenues		8,027	4,115
Italy [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenues	[1]	$ 19	917
Sweden [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenues	[2]		$ 207
[1]	In December 2017 the Company committed to a plan to consolidate certain of its 3D printing operations from its Desenzano del Garda, Italy facility into its Gersthofen, Germany facility (Note 5). Operations at the Desenzano del Garda, Italy facility effectively ceased during the three months ended March 31, 2018 and in December 2018, the Company completed the dissolution of its ExOne Italy S.r.l. subsidiary.
[2]	In March 2017 the Company terminated its Cooperation Agreement with Swerea SWECAST AB (“Swerea”), resulting in an exit of its PSC/EAC operations in Jönköping, Sweden, effective April 1, 2017. Also in March 2017 the Company agreed to an operating lease agreement with Beijer Industri AB, effective April 1, 2017, related to the 3D printing machine and related equipment located on the Swerea premises, previously covered under the Cooperation Agreement with Swerea. For 2017 revenues considered to be originated from Sweden are limited to the PSC/EAC operations which ceased on April 1, 2017. Revenues associated the operating lease agreement with Beijer Industri AB subsequent to April 1, 2017, are considered to be originated from Germany.

Segment, Product and Geograph_5

Segment, Product and Geographic Information - Geographic Information for Long-Lived Assets (Detail) - USD ($) $ in Thousands		Dec. 31, 2018	Dec. 31, 2017
Revenues from External Customers and Long-Lived Assets [Line Items]
Long-lived assets		$ 41,906	$ 46,797
United States [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Long-lived assets		13,603	14,873
Germany [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Long-lived assets		23,249	25,748
Japan [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Long-lived assets		4,650	4,996
Italy [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Long-lived assets	[1]	199	796
Sweden [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Long-lived assets	[2]	$ 205	273
United Kingdom
Revenues from External Customers and Long-Lived Assets [Line Items]
Long-lived assets	[3]		$ 111
[1]	In December 2017 the Company committed to a plan to consolidate certain of its 3D printing operations from its Desenzano del Garda, Italy facility into its Gersthofen, Germany facility (Note 5). Operations at the Desenzano del Garda, Italy facility effectively ceased during the three months ended March 31, 2018 and in December 2018, the Company completed the dissolution of its ExOne Italy S.r.l. subsidiary. At December 31, 2018, long-lived assets represent a 3D printing machine and related equipment held by the Company under an operating lease agreement with a customer. At December 31, 2017, long-lived assets represent certain machinery and other equipment associated with the former Desenzano del Garda facility.
[2]	At December 31, 2018 and 2017, represents a 3D printing machine and related equipment held by the Company under an operating lease agreement with a customer.
[3]	At December 31, 2017, represents a 3D printing machine and related equipment held by the Company under an operating lease agreement with a customer. This customer agreement was terminated during 2018.