ExOne (XONE) 10-Q 10 May 18 2018 Q1 Quarterly report Financial data

Document and Entity Information

Document and Entity Information - shares	3 Months Ended
	Mar. 31, 2018	May 10, 2018
Document And Entity Information [Abstract]
Document Type	10-Q
Amendment Flag	false
Document Period End Date	Mar. 31, 2018
Document Fiscal Year Focus	2,018
Document Fiscal Period Focus	Q1
Trading Symbol	XONE
Entity Registrant Name	ExOne Co
Entity Central Index Key	1,561,627
Current Fiscal Year End Date	--12-31
Entity Filer Category	Accelerated Filer
Entity Common Stock, Shares Outstanding		16,202,119

Condensed Statement of Consolid

Condensed Statement of Consolidated Operations and Comprehensive Loss - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Income Statement [Abstract]
Revenue	$ 11,893	$ 10,869
Cost of sales	9,277	9,266
Gross profit	2,616	1,603
Operating expenses
Research and development	2,795	1,999
Selling, general and administrative	6,202	6,263
Total operating expenses	8,997	8,262
Loss from operations	(6,381)	(6,659)
Other (income) expense
Interest expense	33	22
Other (income) expense ̶ net	(46)	110
Total other (income) expense	(13)	132
Loss before income taxes	(6,368)	(6,791)
Provision for income taxes	17	0
Net loss	$ (6,385)	$ (6,791)
Net loss per common share:
Basic	$ (0.40)	$ (0.42)
Diluted	$ (0.40)	$ (0.42)
Comprehensive loss:
Net loss	$ (6,385)	$ (6,791)
Other comprehensive income:
Foreign currency translation adjustments	1,402	1,026
Comprehensive loss	$ (4,983)	$ (5,765)

Condensed Consolidated Balance

Condensed Consolidated Balance Sheet - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017
Current assets:
Cash and cash equivalents	$ 15,222	$ 21,848
Restricted cash	1,634	330
Accounts receivable ̶ net of allowance of $1,199 (2018) and $1,193 (2017)	5,272	8,647
Inventories ̶ net	18,603	15,430
Prepaid expenses and other current assets	3,188	1,710
Total current assets	43,919	47,965
Property and equipment ̶ net	47,536	46,797
Intangible assets ̶ net		62
Other noncurrent assets	870	736
Total assets	92,325	95,560
Current liabilities:
Current portion of long-term debt	138	137
Current portion of capital leases	19	15
Accounts payable	5,591	4,291
Accrued expenses and other current liabilities	5,700	6,081
Deferred revenue and customer prepayments	8,752	8,282
Total current liabilities	20,200	18,806
Long-term debt ̶ net of current portion	1,473	1,508
Capital leases ̶ net of current portion	46	36
Other noncurrent liabilities	1	1
Total liabilities	21,720	20,351
Contingencies and commitments
Stockholders' equity
Common stock, $0.01 par value, 200,000,000 shares authorized, 16,149,617 (2018) and 16,124,617 (2017) shares issued and outstanding	161	161
Additional paid-in capital	174,097	173,718
Accumulated deficit	(95,571)	(89,186)
Accumulated other comprehensive loss	(8,082)	(9,484)
Total stockholders' equity	70,605	75,209
Total liabilities and stockholders' equity	$ 92,325	$ 95,560

Condensed Consolidated Balance4

Condensed Consolidated Balance Sheet (Parenthetical) - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017
Statement Of Financial Position [Abstract]
Allowance for accounts receivable	$ 1,199	$ 1,193
Common stock, par value	$ 0.01	$ 0.01
Common stock, shares authorized	200,000,000	200,000,000
Common stock, shares issued	16,149,617	16,124,617
Common stock, shares outstanding	16,149,617	16,124,617

Condensed Statement of Consoli5

Condensed Statement of Consolidated Cash Flows - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Operating activities
Net loss	$ (6,385)	$ (6,791)
Adjustments to reconcile net loss to net cash (used for) provided by operations:
Depreciation and amortization	1,488	2,307
Equity-based compensation	379	561
Amortization of debt issuance costs	5	2
Provision for bad debts ̶ net	9	123
Provision for slow-moving, obsolete and lower of cost or net realizable value inventories ̶ net	16	427
Loss (gain) from disposal of property and equipment ̶ net	9	(8)
Changes in assets and liabilities, excluding effects of foreign currency translation adjustments:
Decrease in accounts receivable	3,518	944
Increase in inventories	(3,486)	(295)
Increase in prepaid expenses and other assets	(1,351)	(902)
Increase in accounts payable	1,244	787
Decrease in accrued expenses and other liabilities	(511)	(195)
Increase in deferred revenue and customer prepayments	219	3,203
Net cash (used for) provided by operating activities	(4,846)	163
Investing activities
Capital expenditures	(483)	(249)
Proceeds from sale of property and equipment	25	37
Net cash used for investing activities	(458)	(212)
Financing activities
Payments on long-term debt	(35)	(35)
Payments on capital leases	(4)	(22)
Debt issuance costs	(188)
Net cash used for financing activities	(227)	(57)
Effect of exchange rate changes on cash, cash equivalents, and restricted cash	209	285
Net change in cash, cash equivalents, and restricted cash	(5,322)	179
Cash, cash equivalents, and restricted cash at beginning of period	22,178	28,155
Cash, cash equivalents, and restricted cash at end of period	16,856	28,334
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	814	131
Transfer of internally developed 3D printing machines from property and equipment to inventories for sale	113	395
Property and equipment acquired through financing arrangements	14	48
Property and equipment included in accounts payable	49	$ 25
Property and equipment included in accrued expenses and other current liabilities	50
Debt issuance costs included in accrued expenses and other current liabilities	$ 76

Condensed Statement of Changes

Condensed Statement of Changes in Consolidated Stockholders' Equity (Unaudited) - 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	(6,791)			(6,791)
Other comprehensive income	1,026				1,026
Equity-based compensation	561		561
Common stock issued from equity incentive plan, shares		29,000
Ending Balance at Mar. 31, 2017	82,168	$ 160	171,677	(75,960)	(13,709)
Ending Balance, Shares at Mar. 31, 2017		16,046,000
Beginning Balance at Dec. 31, 2017	$ 75,209	$ 161	173,718	(89,186)	(9,484)
Beginning Balance, Shares at Dec. 31, 2017	16,124,617	16,125,000
Net loss	$ (6,385)			(6,385)
Other comprehensive income	1,402				1,402
Equity-based compensation	379		379
Common stock issued from equity incentive plan, shares		25,000
Ending Balance at Mar. 31, 2018	$ 70,605	$ 161	$ 174,097	$ (95,571)	$ (8,082)
Ending Balance, Shares at Mar. 31, 2018	16,149,617	16,150,000

Basis of Presentation

Basis of Presentation	3 Months Ended
	Mar. 31, 2018
Accounting Policies [Abstract]
Basis of Presentation	Note 1. Basis of Presentation 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 condensed consolidated financial statements include the accounts of ExOne, its wholly-owned subsidiaries, ExOne Americas LLC (United States); ExOne GmbH (Germany); ExOne Property GmbH (Germany); ExOne KK (Japan); ExOne Italy S.r.l (Italy); and through December 2017, ExOne Sweden AB (Sweden). Collectively, the consolidated group is referred to as the “Company”. The Company filed a registration statement on Form S-3 (No. 333-223690) Basis of Presentation The condensed consolidated financial statements of the Company are unaudited. The condensed consolidated financial statements include all adjustments, consisting of normal recurring adjustments, considered necessary by management to fairly state the results of operations, financial position and cash flows of the Company. All material intercompany transactions and balances have been eliminated in consolidation. The results reported in these condensed consolidated financial statements are not necessarily indicative of the results that may be expected for the entire year. The December 31, 2017 condensed consolidated balance sheet data was derived from the audited financial statements but does not include all disclosures required by accounting principles generally accepted in the United States of America (“GAAP”). This Quarterly Report on Form 10-Q should be read in connection with the Company’s Annual Report on Form 10-K for the year ended December 31, 2017, which includes all disclosures required by GAAP. The preparation of these condensed 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. Certain amounts relating to provision for slow-moving, obsolete and lower of cost or net realizable value inventories – net ($427) in the accompanying condensed statement of consolidated cash flows for the three months ended March 31, 2017, have been reclassified from decrease in inventories to conform to current period presentation. Recently Adopted Accounting Guidance On January 1, 2018, the Company adopted ASU 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 were assessed and determined to be either not applicable or are currently expected to have no impact on the consolidated financial statements of the Company. In February 2016, the FASB issued ASU 2016-02, “Leases.” As a result of this ASU, lessees will be required to recognize the following for all leases (with the exception of short-term leases) at the commencement date: a lease liability, which is a lessee’s obligation to make lease payments arising from a lease, measured on a discounted basis; and a right-of-use asset, which is an asset that represents the lessee’s right to use, or control the use of, a specified asset for the lease term. As a result of this ASU, lessor accounting is largely unchanged and lessees will no longer be provided with a source of off-balance sheet financing. This ASU becomes effective for the Company on January 1, 2019. Early adoption is permitted. Lessees (for capital and operating leases) and lessors (for sales-type, direct financing, and operating leases) must apply a modified retrospective transition approach for leases existing at, or entered into after, the beginning of the earliest comparative period presented in the consolidated financial statements. The modified retrospective approach would not require any transition accounting for leases that expired before the earliest comparative period presented. Lessees and lessors may not apply a full retrospective transition approach. Management is currently evaluating the potential impact of this ASU on the consolidated financial statements of the Company. 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. Management is currently evaluating the potential impact of these collective changes on the consolidated financial statements of the Company. The Company plans to utilize the modified retrospective method in connection with its future adoption of this ASU, as amended.

Liquidity

Liquidity	3 Months Ended
	Mar. 31, 2018
Organization Consolidation And Presentation Of Financial Statements [Abstract]
Liquidity	Note 2. Liquidity On February 6, 2013, the Company commenced an initial public offering of 6,095,000 shares of its common stock at a price to the public of $18.00 per share, of which 5,483,333 shares of common stock were sold by the Company and 611,667 shares of common stock were sold by a selling stockholder (including consideration of the exercise of the underwriters’ over-allotment option). The Company received approximately $90,371 in unrestricted net proceeds in connection with this offering (net of underwriting commissions and offering costs). On September 9, 2013, the Company commenced a secondary public offering of 3,054,400 shares of its common stock at a price to the public of $62.00 per share, of which 1,106,000 shares of common stock were sold by the Company and 1,948,400 shares of common stock were sold by selling stockholders (including consideration of the exercise of the underwriters’ over-allotment option). The Company received approximately $64,948 in unrestricted net proceeds in connection with this offering (net of underwriting commissions and offering costs). On January 8, 2016, the Company announced that it had entered into 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”). On January 11, 2016, the Company announced that it had entered into a subscription agreement with Rockwell Forest Products, Inc. and S. Kent Rockwell for the registered direct offering and sale of 1,423,877 shares of ExOne common stock at a per share price of $9.13 (a $0.50 premium from the closing price on the close of business on January 8, 2016). Both Rockwell Forest Products, Inc. and S. Kent Rockwell were identified as related parties to the Company, as S. Kent Rockwell served as Chairman and Chief Executive Officer of the Company and was the controlling shareholder of Rockwell Forest Products, Inc. at the time of the transaction. The terms of this transaction were reviewed and approved by a sub-committee of independent members of the Board of Directors of the Company (which included each of the members of the Audit Committee of the Board of Directors). The sub-committee of independent members of the Board of Directors of the Company were advised on the transaction by an independent financial advisor and independent legal counsel. Concurrent with the approval of this sale of common stock under the terms identified, a separate sub-committee of independent members of the Board of Directors of the Company approved the termination of the Company’s revolving credit facility with RHI Investments, LLC. Following completion of the registered direct offering on January 13, 2016, the Company received gross proceeds of approximately $13,000. Unrestricted net proceeds to the Company from the sale of common stock in the registered direct offering were approximately $12,447 (after deducting offering costs of approximately $553). The Company has incurred a net loss in each of its annual periods since its inception. As shown in the accompanying condensed statement of consolidated operations and comprehensive loss, the Company incurred a net loss of approximately $6,385 for the three months ended March 31, 2018. As noted above, the Company has received cumulative unrestricted net proceeds from the sale of its common stock of approximately $168,361 to fund its operations. At March 31, 2018, the Company had approximately $15,222 in unrestricted cash and cash equivalents. In addition, on March 12, 2018, the Company entered into a three-year, $15,000 revolving credit facility with a related party (Note 11). 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. Further, the Company may 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	3 Months Ended
	Mar. 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: Three Months Ended March 31, Foreign currency translation adjustments 2018 2017 Balance at beginning of period $ (9,484 ) $ (14,735 ) Other comprehensive income 1,402 1,026 Balance at end of period $ (8,082 ) $ (13,709 ) 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. There were no tax impacts related to income tax rate changes and no amounts were reclassified to earnings for either of the periods presented.

Loss Per Share

Loss Per Share	3 Months Ended
	Mar. 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 common 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 each of the three months ended March 31, 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 (685,970 – 2018 and 357,137 – 2017) and unvested restricted stock issued (52,502 – 2018 and 95,337 – 2017), was anti-dilutive. The information used to compute basic and diluted net loss per common share was as follows: Three Months Ended March 31, 2018 2017 Net loss $ (6,385 ) $ (6,791 ) Weighted average shares outstanding (basic and diluted) 16,138,506 16,028,906 Net loss per common share: Basic $ (0.40 ) $ (0.42 ) Diluted $ (0.40 ) $ (0.42 )

Restructuring

Restructuring	3 Months Ended
	Mar. 31, 2018
Restructuring And Related Activities [Abstract]
Restructuring	Note 5. Restructuring Desenzano del Garda, Italy In December 2017, the Company committed to a plan to consolidate certain of its three-dimensional (“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 the three months ended December 31, 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 the three months ended March 31, 2018, the Company recorded an additional charge of approximately $245 associated with other exit costs ($17) and asset impairments ($228) related to this plan. Charges associated with other exit costs recorded during the three months ended March 31, 2018 were recorded to cost of sales in the accompanying condensed statement of consolidated operations and comprehensive loss. Charges associated with asset impairments recorded during the three months ended March 31, 2018 were recorded to cost of sales as a component of depreciation expense in the accompanying condensed 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 previously recorded associated with involuntary employee terminations during the three months ended March 31, 2018. Amounts associated with other exit costs (remaining facility rent payments) of approximately $11 are expected to be settled by the Company during the three months ended June 30, 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 indirect printing technology in North America which resulted in a refocus of the Company’s operational strategy. As a result of these actions, during the three months ended March 31, 2017, the Company recorded charges of approximately $984, including approximately $110 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 condensed 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 condensed statement of consolidated operations and comprehensive loss. During the three months ended June 30, 2017, the Company recorded an additional charge of approximately $32 associated with an additional involuntary employee termination which required a service commitment through April 2017. 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 condensed statement of consolidated operations and comprehensive loss). During the three months ended June 30, 2017, the Company recorded a loss on disposal of approximately $42. 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 condensed statement of consolidated operations and comprehensive loss) during the three months ended June 30, 2017, of approximately $347. Additionally, the Company recorded an impairment loss during the three months ended March 31, 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	3 Months Ended
	Mar. 31, 2018
Asset Impairment Charges [Abstract]
Impairment	Note 6. Impairment During the three months ended March 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	3 Months Ended
	Mar. 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 condensed consolidated balance sheet to the same such amounts shown in the accompanying condensed statement of consolidated cash flows: March 31, December 31, 2018 2017 Cash and cash equivalents $ 15,222 $ 21,848 Restricted cash 1,634 330 Cash, cash equivalents, and restricted cash $ 16,856 $ 22,178 Restricted cash at March 31, 2018 includes approximately $1,134 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 10).

Inventories

Inventories	3 Months Ended
	Mar. 31, 2018
Inventory Disclosure [Abstract]
Inventories	Note 8. Inventories Inventories consist of the following: March 31, December 31, 2018 2017 Raw materials and components $ 8,516 $ 7,171 Work in process 5,254 4,630 Finished goods 4,833 3,629 $ 18,603 $ 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 March 31, 2018 and December 31, 2017, the allowance for slow-moving and obsolete inventories was approximately $3,530 and $3,437, respectively, and has been reflected as a reduction to inventories (principally raw materials and components). During the three months ended March 31, 2018 and 2017, the Company recorded a net (credit) charge of approximately ($15) and $206, respectively, to cost of sales in the accompanying condensed statement of consolidated operations and comprehensive loss associated with certain inventories for which cost was determined to exceed net realizable value.

Product Warranty Reserves

Product Warranty Reserves	3 Months Ended
	Mar. 31, 2018
Product Warranties Disclosures [Abstract]
Product Warranty Reserves	Note 9. Product Warranty Reserves Substantially all of the Company’s 3D printing machines 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. The following table summarizes changes in product warranty reserves (such amounts reflected in accrued expenses and other current liabilities in the accompanying condensed consolidated balance sheet for each respective period): Three Months Ended March 31, 2018 2017 Balance at beginning of period $ 1,300 $ 1,115 Provisions for new issuances 219 236 Payments (208 ) (169 ) Reserve adjustments (187 ) (150 ) Foreign currency translation adjustments 24 12 Balance at end of period $ 1,148 $ 1,044

Contingencies and Commitments

Contingencies and Commitments	3 Months Ended
	Mar. 31, 2018
Commitments And Contingencies Disclosure [Abstract]
Contingencies and Commitments	Note 10. 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. The Company and its subsidiaries are 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. Commitments In the normal course of its operations, ExOne GmbH issues short-term financial guarantees and letters of credit to third parties in connection with certain commercial transactions requiring security. ExOne GmbH maintains a credit facility 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 an aggregate of approximately $1,600 (€1,300). In addition, ExOne GmbH may use the credit facility for short-term, fixed-rate loans in minimum increments of approximately $100 (€100) with minimum terms of at least 30 May 2018 In connection with the related party revolving credit facility agreement entered into by the Company on March 12, 2018 (Note 11), the Company was required to post cash collateral against outstanding financial guarantees and letters of credit associated with the credit facility (Note 7). In addition to amounts issued by ExOne GmbH under the credit facility, from time to time, ExOne GmbH enters into separate agreements with the same German bank for additional capacity for financial guarantees and letters of credit associated with certain commercial transactions requiring security. Terms of the separate agreements are substantially similar to those of the existing credit facility except that the German bank requires cash collateral to be posted by ExOne GmbH in connection with any related issuance. At March 31, 2018, total outstanding financial guarantees and letters of credit issued by ExOne GmbH under these separate agreements were approximately $99 (€80) with an expiration date of June 2022. Related to this separate agreement, the requirement for cash collateral was waived by the German bank as it also represents the counterparty in the related transaction.

Related Party Revolving Credit

Related Party Revolving Credit Facility	3 Months Ended
	Mar. 31, 2018
Related Party Transactions [Abstract]
Related Party Revolving Credit Facility	Note 11. 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, the Executive Chairman of the Company (a related party), 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 6.9% at inception and March 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 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 and March 31, 2018, the total estimated value of collateral was in significant excess of the maximum capacity of 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 the Executive Chairman 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 a sub-committee of independent members of the Board of Directors of the Company (which included each of the members of the Audit Committee of the Board of Directors). 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 pursuant to a separate Escrow Agreement by and among the parties. Loan proceeds held in escrow will be 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 through March 31, 2018. The Company incurred approximately $264 in debt issuance costs associated with the LBM Credit Agreement (including the aforementioned up front commitment fee paid at closing to LBM). During the three months ended March 31, 2018, the Company recorded interest expense relating to the LBM Credit Agreement of approximately $10, including approximately $4 associated with amortization of debt issuance costs (resulting in approximately $260 in remaining debt issuance costs at March 31, 2018, of which $88 is included in prepaid expenses and other current assets and $172 is included in other noncurrent assets in the accompanying condensed consolidated balance sheet) and $6 associated with the commitment fee on the unused portion of the revolving credit facility for the period from March 12, 2018 through March 31, 2018 (such amounts included in accrued expenses and other current liabilities in the accompanying condensed consolidated balance sheet at March 31, 2018). Amounts payable to LBM at March 31, 2018, were settled by the Company in April 2018.

Income Taxes

Income Taxes	3 Months Ended
	Mar. 31, 2018
Income Tax Disclosure [Abstract]
Income Taxes	Note 12. Income Taxes The provision for income taxes for the three months ended March 31, 2018 and 2017 was $17 and $0, respectively. The Company has completed a discrete period computation of its provision for income taxes for each of the periods presented. The discrete period computation was required as a result of jurisdictions with losses before income taxes for which no tax benefit can be recognized and an inability to generate reliable estimates for results in certain jurisdictions as a result of inconsistencies in generating net operating profits (losses) in those jurisdictions. The effective tax rate for the three months ended March 31, 2018 and 2017 was 0.3% (provision on a loss) and 0.0%, respectively. The effective tax rate differs from the United States federal statutory rate of 21.0% (2018) and 34.0% (2017) for each of the periods presented primarily due to net changes in valuation allowances for the periods. 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% to 21% 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 (“SAB 118”), which allows the Company to record provisional amounts during a measurement period not to extend beyond one year of the enactment date. As ongoing guidance and accounting interpretation are expected over the next year, the Company considers its accounting of the deferred tax re-measurements and other items to be incomplete due to the forthcoming guidance and its ongoing analysis of final December 31, 2017 data and tax positions. No provisional amounts have been recorded by the Company. The Company expects to complete its analysis within the measurement period in accordance with SAB 118. 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 Company has a liability for uncertain tax positions related to certain capitalized expenses and intercompany transactions. At March 31, 2018 and December 31, 2017, the liability for uncertain tax positions was approximately $883 and $858, respectively, and was included in accrued expenses and other current liabilities in the accompanying condensed consolidated balance sheet. At March 31, 2018 and December 31, 2017, the Company had an additional liability for uncertain tax positions related to its ExOne GmbH (Germany) subsidiary of approximately $348 and $323, respectively, which were fully offset against net operating loss carryforwards. At March 31, 2018 and December 31, 2017, the Company had an additional liability for uncertain tax positions related to its ExOne KK (Japan) subsidiary of approximately $673 and $594, respectively, which were fully offset against net operating loss carryforwards. At March 31, 2018, the Company’s ExOne GmbH (2010-2013) and ExOne Property GmbH (2013) subsidiaries were under examination by local taxing authorities. The Company is unable to reasonably predict an outcome related to this examination, the result of which may be material in a future period to the financial position, results from operations and cash flows of the Company.

Equity-Based Compensation

Equity-Based Compensation	3 Months Ended
	Mar. 31, 2018
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Equity-Based Compensation	Note 13. Equity-Based Compensation On January 24, 2013, the Board of Directors of the Company 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 of Directors, provided that the maximum number of shares authorized under the Plan will not exceed 1,992,241 shares, subject to certain adjustments. 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 a contractual life which expires 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 of Directors of the Company adopted the 2018 Annual Incentive Program (the “Program”) as a subplan under the Plan. The Program provides an opportunity for performance-based compensation to senior executive officers of the Company (excluding the Executive Chairman), among others. The target annual incentive for each Program participant is expressed as a percentage of base salary and is conditioned on the achievement of certain financial goals (as approved by the Compensation Committee of the Board of Directors) or a combination of financial and non-financial goals. The Compensation Committee of the Board of Directors retains negative discretion over amounts payable under the Program. For 2018, the total target amount payable under the Program is approximately $1,423, with certain amounts to be settled with participants in cash, equity or a combination thereof. During the three months ended March 31, 2018, total compensation expense associated with the Program was approximately $142, split between cost of sales ($21), research and development ($43) and selling general and administrative expenses ($78) in the accompanying condensed statement of consolidated operations The following table summarizes the total equity-based compensation expense recognized under the Plan: Three Months Ended March 31, 2018 2017 Equity-based compensation expense recognized: Stock options $ 203 $ 343 Restricted stock 106 218 Other (a) 70 — Total equity-based compensation expense before income taxes 379 561 Benefit for income taxes (b) — — Total equity-based compensation expense net of income taxes $ 379 $ 561 (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 based on valuation allowances against net deferred tax assets. At March 31, 2018, total future compensation expense related to unvested awards yet to be recognized by the Company was approximately $679 for stock options and $384 for restricted stock. Total future compensation expense related to unvested awards yet to be recognized by the Company is expected to be recognized over a weighted-average remaining vesting period of approximately 1.3 years. During the three months ended March 31, 2018, the fair value of stock options granted was estimated on the date of grant using the Black-Scholes option pricing model with the following assumptions: March 16, 2018 Weighted average fair value per stock option $3.77 Volatility 62.58% Average risk-free interest rate 2.45% Dividend yield 0.00% Expected term (years) 3.3 During the three months ended March 31, 2017, the fair value of stock options granted was estimated on the date of grant using the Black-Scholes option pricing model with the following assumptions: February 10, 2017 Weighted average fair value per stock option $5.46 - $5.75 Volatility 62.89% - 63.75% Average risk-free interest rate 1.89% - 1.94% Dividend yield 0.00% Expected term (years) 5.0 - 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: Three Months Ended March 31, 2018 2017 Number Options Weighted Weighted Average Grant Date Fair Value Number Options Weighted 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 24,000 $ 8.36 $ 3.77 44,000 $ 10.10 $ 5.51 Stock options exercised — $ — $ — — $ — $ — Stock options forfeited (12,500 ) $ 7.91 $ 3.40 (500 ) $ 15.74 $ 9.60 Stock options expired — $ — $ — (666 ) $ 15.74 $ 9.60 Outstanding at end of period 685,970 $ 11.53 $ 6.37 357,137 $ 15.08 $ 8.99 Stock options exercisable at end of period 424,627 $ 12.93 $ 7.37 232,471 $ 15.77 $ 9.47 Stock options expected to vest at end of period 261,343 $ 9.25 $ 4.74 124,666 $ 13.80 $ 8.11 At March 31, 2018, there was no intrinsic value associated with stock options exercisable or expected to vest. The weighted average remaining contractual term of stock options exercisable and expected to vest at March 31, 2018, was approximately 6.3 years and 6.6 years, respectively. There were no stock option exercises during the three months ended March 31, 2018 or 2017. The activity for restricted stock was as follows: Three Months Ended March 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 25,000 $ 8.21 30,000 $ 10.10 Restricted stock vested (25,000 ) $ 10.10 (28,834 ) $ 14.69 Restricted stock forfeited — $ — — $ — Outstanding at end of period 52,502 $ 10.17 95,337 $ 12.85 Restricted stock expected to vest at end of period 52,502 $ 10.17 95,337 $ 12.85 Restricted stock vesting during the three months ended March 31, 2018 and 2017, had a fair value of approximately $205 and $299, respectively.

Fair Value Measurements

Fair Value Measurements	3 Months Ended
	Mar. 31, 2018
Fair Value Disclosures [Abstract]
Fair Value Measurements	Note 14. 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 both 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 remained outstanding at March 31, 2017, and during the three months ended March 31, 2017, generated an unrealized loss of less than $1 (€1). Neither of the contracts was designated as a hedging instrument and accordingly, realized and unrealized gains (losses) have been recorded to other expense (income) – net in the accompanying condensed statement of consolidated operations and comprehensive loss. The Company classified both contracts as Level 2 fair value measurements. There were no such contracts entered into by the Company during the three months ended March 31, 2018. There were no such contracts outstanding at either March 31, 2018 or December 31, 2017. The carrying values and fair values of other financial instruments (assets and liabilities) not required to be recorded at fair value were as follows: March 31, December 31, 2018 2017 Carrying Value Fair Value Carrying Value Fair Value Cash and cash equivalents $ 15,222 $ 15,222 $ 21,848 $ 21,848 Restricted cash $ 1,634 $ 1,634 $ 330 $ 330 Debt issuance costs (a) $ 260 $ — $ — $ — Current portion of long-term debt (b) $ 138 $ 144 $ 137 $ 142 Current portion of capital leases $ 19 $ 19 $ 15 $ 15 Long-term debt ̶ (b) $ 1,473 $ 1,496 $ 1,508 $ 1,533 Capital leases ̶ $ 46 $ 46 $ 36 $ 36 (a) Represents debt issuance costs associated with the Company’s related party revolving credit facility (Note 11) of which $88 are included in prepaid expenses and other current assets and $172 are included in other noncurrent assets in the accompanying condensed consolidated balance sheet at March 31, 2018. (b) Carrying values at The carrying amounts of cash and cash equivalents, restricted cash, current portion of long-term debt and current portion of capital leases approximate fair value due to their short-term maturities. The fair value of long-term debt – net of current portion and capital leases – net of current portion have been estimated by management based on the consideration of applicable interest rates (including certain instruments at variable or floating rates) and other available information (including quoted prices of similar instruments available to the Company). Cash and cash equivalents and restricted cash are classified in Level 1; current portion of long-term debt, current portion of capital leases, long-term debt – net of current portion and capital leases – net of current portion are classified in Level 2 .

Concentration of Credit Risk

Concentration of Credit Risk	3 Months Ended
	Mar. 31, 2018
Risks And Uncertainties [Abstract]
Concentration of Credit Risk	Note 15. Concentration of Credit Risk During the three months ended March 31, 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. For the three months ended March 31, 2018 and 2017, the Company’s five most significant customers represented approximately 37.2% and 40.0% of total revenue, respectively. At March 31, 2018 and December 31, 2017, accounts receivable from the Company’s five most significant customers were approximately $1,262 and $4,199, respectively.

Related Party Transactions

Related Party Transactions	3 Months Ended
	Mar. 31, 2018
Related Party Transactions [Abstract]
Related Party Transactions	Note 16. Related Party Transactions Revenues Sales of products and/or services to related parties for the three months ended March 31, 2017 were approximately $8. None of the transactions met a threshold requiring review and approval by the Audit Committee of the Board of Directors of the Company. There were no sales of products and/or services to related parties during the three months ended March 31, 2018. There were no amounts due from related parties at March 31, 2018 or December 31, 2017. Expenses Purchases of products and/or services from related parties during the three months ended March 31, 2018 and 2017, were approximately $6 and $3, respectively. Purchases of products and/or services by the Company during the three months ended March 31, 2018 and 2017 included website design services and leased office space from related parties under common control by the Executive Chairman of the Company. None of the transactions met a threshold requiring review and approval by the Audit Committee of the Board of Directors of the Company. Amounts due to related parties at March 31, 2018 and December 31, 2017, were approximately $4 and $1, respectively. Amounts due to related parties for both periods are reflected in accounts payable in the accompanying condensed consolidated balance sheet. Other Refer to Note 11 for further discussion relating to a revolving credit facility with a related party entered into in March 2018.

Subsequent Events

Subsequent Events	3 Months Ended
	Mar. 31, 2018
Subsequent Events [Abstract]
Subsequent Events	Note 17. Subsequent Events The Company has evaluated all of its activities and concluded that no subsequent events have occurred that would require recognition in the condensed consolidated financial statements or disclosure in the notes to the condensed consolidated financial statements.

Basis of Presentation (Policies

Basis of Presentation (Policies)	3 Months Ended
	Mar. 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 condensed consolidated financial statements include the accounts of ExOne, its wholly-owned subsidiaries, ExOne Americas LLC (United States); ExOne GmbH (Germany); ExOne Property GmbH (Germany); ExOne KK (Japan); ExOne Italy S.r.l (Italy); and through December 2017, ExOne Sweden AB (Sweden). Collectively, the consolidated group is referred to as the “Company”. The Company filed a registration statement on Form S-3 (No. 333-223690) Basis of Presentation The condensed consolidated financial statements of the Company are unaudited. The condensed consolidated financial statements include all adjustments, consisting of normal recurring adjustments, considered necessary by management to fairly state the results of operations, financial position and cash flows of the Company. All material intercompany transactions and balances have been eliminated in consolidation. The results reported in these condensed consolidated financial statements are not necessarily indicative of the results that may be expected for the entire year. The December 31, 2017 condensed consolidated balance sheet data was derived from the audited financial statements but does not include all disclosures required by accounting principles generally accepted in the United States of America (“GAAP”). This Quarterly Report on Form 10-Q should be read in connection with the Company’s Annual Report on Form 10-K for the year ended December 31, 2017, which includes all disclosures required by GAAP. The preparation of these condensed 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. Certain amounts relating to provision for slow-moving, obsolete and lower of cost or net realizable value inventories – net ($427) in the accompanying condensed statement of consolidated cash flows for the three months ended March 31, 2017, have been reclassified from decrease in inventories to conform to current period presentation.
Recently Adopted and Issued Accounting Guidance	Recently Adopted Accounting Guidance On January 1, 2018, the Company adopted ASU 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 were assessed and determined to be either not applicable or are currently expected to have no impact on the consolidated financial statements of the Company. In February 2016, the FASB issued ASU 2016-02, “Leases.” As a result of this ASU, lessees will be required to recognize the following for all leases (with the exception of short-term leases) at the commencement date: a lease liability, which is a lessee’s obligation to make lease payments arising from a lease, measured on a discounted basis; and a right-of-use asset, which is an asset that represents the lessee’s right to use, or control the use of, a specified asset for the lease term. As a result of this ASU, lessor accounting is largely unchanged and lessees will no longer be provided with a source of off-balance sheet financing. This ASU becomes effective for the Company on January 1, 2019. Early adoption is permitted. Lessees (for capital and operating leases) and lessors (for sales-type, direct financing, and operating leases) must apply a modified retrospective transition approach for leases existing at, or entered into after, the beginning of the earliest comparative period presented in the consolidated financial statements. The modified retrospective approach would not require any transition accounting for leases that expired before the earliest comparative period presented. Lessees and lessors may not apply a full retrospective transition approach. Management is currently evaluating the potential impact of this ASU on the consolidated financial statements of the Company. 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. Management is currently evaluating the potential impact of these collective changes on the consolidated financial statements of the Company. The Company plans to utilize the modified retrospective method in connection with its future adoption of this ASU, as amended.
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 common 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 Comprehensi25

Accumulated Other Comprehensive Loss (Tables)	3 Months Ended
	Mar. 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: Three Months Ended March 31, Foreign currency translation adjustments 2018 2017 Balance at beginning of period $ (9,484 ) $ (14,735 ) Other comprehensive income 1,402 1,026 Balance at end of period $ (8,082 ) $ (13,709 )

Loss Per Share (Tables)

Loss Per Share (Tables)	3 Months Ended
	Mar. 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: Three Months Ended March 31, 2018 2017 Net loss $ (6,385 ) $ (6,791 ) Weighted average shares outstanding (basic and diluted) 16,138,506 16,028,906 Net loss per common share: Basic $ (0.40 ) $ (0.42 ) Diluted $ (0.40 ) $ (0.42 )

Cash, Cash Equivalents, and R27

Cash, Cash Equivalents, and Restricted Cash (Tables)	3 Months Ended
	Mar. 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 condensed consolidated balance sheet to the same such amounts shown in the accompanying condensed statement of consolidated cash flows: March 31, December 31, 2018 2017 Cash and cash equivalents $ 15,222 $ 21,848 Restricted cash 1,634 330 Cash, cash equivalents, and restricted cash $ 16,856 $ 22,178

Inventories (Tables)

Inventories (Tables)	3 Months Ended
	Mar. 31, 2018
Inventory Disclosure [Abstract]
Schedule of Inventories	Inventories consist of the following: March 31, December 31, 2018 2017 Raw materials and components $ 8,516 $ 7,171 Work in process 5,254 4,630 Finished goods 4,833 3,629 $ 18,603 $ 15,430

Product Warranty Reserves (Tabl

Product Warranty Reserves (Tables)	3 Months Ended
	Mar. 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 condensed consolidated balance sheet for each respective period): Three Months Ended March 31, 2018 2017 Balance at beginning of period $ 1,300 $ 1,115 Provisions for new issuances 219 236 Payments (208 ) (169 ) Reserve adjustments (187 ) (150 ) Foreign currency translation adjustments 24 12 Balance at end of period $ 1,148 $ 1,044

Equity-Based Compensation (Tabl

Equity-Based Compensation (Tables)	3 Months Ended
	Mar. 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 under the Plan: Three Months Ended March 31, 2018 2017 Equity-based compensation expense recognized: Stock options $ 203 $ 343 Restricted stock 106 218 Other (a) 70 — Total equity-based compensation expense before income taxes 379 561 Benefit for income taxes (b) — — Total equity-based compensation expense net of income taxes $ 379 $ 561 (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 based on valuation allowances against net deferred tax assets.
Assumptions for Fair Value of Stock Options Granted Estimated on the Date of Grant Using the Black-Scholes Option	During the three months ended March 31, 2018, the fair value of stock options granted was estimated on the date of grant using the Black-Scholes option pricing model with the following assumptions: March 16, 2018 Weighted average fair value per stock option $3.77 Volatility 62.58% Average risk-free interest rate 2.45% Dividend yield 0.00% Expected term (years) 3.3 During the three months ended March 31, 2017, the fair value of stock options granted was estimated on the date of grant using the Black-Scholes option pricing model with the following assumptions: February 10, 2017 Weighted average fair value per stock option $5.46 - $5.75 Volatility 62.89% - 63.75% Average risk-free interest rate 1.89% - 1.94% Dividend yield 0.00% Expected term (years) 5.0 - 5.5
Summary of Activity for Stock Options	The activity for stock options was as follows: Three Months Ended March 31, 2018 2017 Number Options Weighted Weighted Average Grant Date Fair Value Number Options Weighted 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 24,000 $ 8.36 $ 3.77 44,000 $ 10.10 $ 5.51 Stock options exercised — $ — $ — — $ — $ — Stock options forfeited (12,500 ) $ 7.91 $ 3.40 (500 ) $ 15.74 $ 9.60 Stock options expired — $ — $ — (666 ) $ 15.74 $ 9.60 Outstanding at end of period 685,970 $ 11.53 $ 6.37 357,137 $ 15.08 $ 8.99 Stock options exercisable at end of period 424,627 $ 12.93 $ 7.37 232,471 $ 15.77 $ 9.47 Stock options expected to vest at end of period 261,343 $ 9.25 $ 4.74 124,666 $ 13.80 $ 8.11
Summary of Activity for Restricted Stock Awards	The activity for restricted stock was as follows: Three Months Ended March 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 25,000 $ 8.21 30,000 $ 10.10 Restricted stock vested (25,000 ) $ 10.10 (28,834 ) $ 14.69 Restricted stock forfeited — $ — — $ — Outstanding at end of period 52,502 $ 10.17 95,337 $ 12.85 Restricted stock expected to vest at end of period 52,502 $ 10.17 95,337 $ 12.85

Fair Value Measurements (Tables

Fair Value Measurements (Tables)	3 Months Ended
	Mar. 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: March 31, December 31, 2018 2017 Carrying Value Fair Value Carrying Value Fair Value Cash and cash equivalents $ 15,222 $ 15,222 $ 21,848 $ 21,848 Restricted cash $ 1,634 $ 1,634 $ 330 $ 330 Debt issuance costs (a) $ 260 $ — $ — $ — Current portion of long-term debt (b) $ 138 $ 144 $ 137 $ 142 Current portion of capital leases $ 19 $ 19 $ 15 $ 15 Long-term debt ̶ (b) $ 1,473 $ 1,496 $ 1,508 $ 1,533 Capital leases ̶ $ 46 $ 46 $ 36 $ 36 (a) Represents debt issuance costs associated with the Company’s related party revolving credit facility (Note 11) of which $88 are included in prepaid expenses and other current assets and $172 are included in other noncurrent assets in the accompanying condensed consolidated balance sheet at March 31, 2018. (b) Carrying values at

Basis of Presentation - Additio

Basis of Presentation - Additional Information (Detail) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017	Jan. 01, 2017
Organization Consolidation And Presentation Of Financial Statements Disclosure [Line Items]
State of incorporation	Delaware
Date of incorporation	Jan. 1, 2013
Provision (recoveries) for slow-moving, obsolete and lower of cost or market inventories ̶ net		$ (427)
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)
Subsidiary Guarantor [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	Jan. 13, 2016	Jan. 11, 2016	Jan. 08, 2016	Sep. 09, 2013	Feb. 06, 2013	Mar. 31, 2018	Mar. 31, 2016	Dec. 31, 2017
Organization Consolidation And Presentation Of Financial Statements Disclosure [Line Items]
Net income (loss)							$ (6,385,000)
Cumulative unrestricted net proceeds of secondary public offering							168,361,000
Cash and cash equivalents							15,222,000		$ 21,848,000
LBM Holdings, LLC [Member] | Revolving Credit Facility [Member]
Organization Consolidation And Presentation Of Financial Statements Disclosure [Line Items]
Credit facility, expiration period	3 years
Line of credit facility, maximum borrowing capacity	$ 15,000,000						$ 15,000,000
IPO [Member]
Organization Consolidation And Presentation Of Financial Statements Disclosure [Line Items]
Common stock, new issuances						6,095,000
Common stock price per share						$ 18
Common stock, new shares sold by Company						5,483,333
Common stock, new shares sold by stockholder						611,667
Unrestricted net proceeds of initial public offering						$ 90,371,000
Secondary Public Offering [Member]
Organization Consolidation And Presentation Of Financial Statements Disclosure [Line Items]
Common stock, new issuances					3,054,400
Common stock price per share					$ 62
Common stock, new shares sold by Company					1,106,000
Common stock, new shares sold by stockholder					1,948,400
Unrestricted net proceeds of secondary public offering					$ 64,948,000
At Market Issuance Offering [Member] | FBR Capital Markets & Co. and MLV & Co. LLC [Member]
Organization Consolidation And Presentation Of Financial Statements Disclosure [Line Items]
Common stock, new shares sold by Company							0	91,940
Unrestricted net proceeds of secondary public offering								$ 595,000
Percentage of commission on sale of common stock				3.00%
Initial reimbursement of certain legal expenses				$ 25,000
Gross proceeds from the sale of shares								843,000
Offering costs								248,000
Payments related to initial reimbursement of certain legal expenses and commissions								$ 50,000
At Market Issuance Offering [Member] | FBR Capital Markets & Co. and MLV & Co. LLC [Member] | Maximum [Member]
Organization Consolidation And Presentation Of Financial Statements Disclosure [Line Items]
Sale of common stock, value				$ 50,000,000
At Market Issuance Offering [Member] | FBR Capital Markets & Co. and MLV & Co. LLC [Member] | Weighted Average [Member]
Organization Consolidation And Presentation Of Financial Statements Disclosure [Line Items]
Common stock price per share								$ 9.17
Registered Direct Offering [Member] | Rockwell Forest Products, Inc. and S. Kent Rockwell [Member]
Organization Consolidation And Presentation Of Financial Statements Disclosure [Line Items]
Common stock price per share			$ 9.13
Common stock, new shares sold by Company			1,423,877
Unrestricted net proceeds of secondary public offering		$ 12,447,000
Gross proceeds from the sale of shares		13,000,000
Offering costs		$ 553,000
Premium per share on closing price			$ 0.50

Accumulated Other Comprehensi34

Accumulated Other Comprehensive Loss - Summary of Changes in the Components of Accumulated Other Comprehensive Loss (Detail) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Statement Of Income And Comprehensive Income [Abstract]
Balance at beginning of period	$ (9,484)	$ (14,735)
Other comprehensive income	1,402	1,026
Balance at end of period	$ (8,082)	$ (13,709)

Accumulated Other Comprehensi35

Accumulated Other Comprehensive Loss - Additional Information (Detail) - USD ($)	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Statement Of Income And Comprehensive Income [Abstract]
Accumulated other comprehensive loss, tax	$ 0	$ 0
Amounts reclassified to earnings from accumulated other comprehensive loss	$ 0	$ 0

Loss Per Share - Additional Inf

Loss Per Share - Additional Information (Detail) - shares	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Stock Option [Member]
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Potential shares of anti-dilutive common stock	685,970	357,137
Restricted Stock [Member]
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Potential shares of anti-dilutive common stock	52,502	95,337

Loss Per Share - Computation of

Loss Per Share - Computation of Basic and Diluted Loss Per Common Share (Detail) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Earnings Per Share [Abstract]
Net loss	$ (6,385)	$ (6,791)
Weighted average shares outstanding (basic and diluted)	16,138,506	16,028,906
Net loss per common share:
Basic	$ (0.40)	$ (0.42)
Diluted	$ (0.40)	$ (0.42)

Restructuring - Additional Info

Restructuring - Additional Information (Detail) - USD ($)	May 09, 2017	Apr. 21, 2017	Mar. 31, 2018	Dec. 31, 2017	Jun. 30, 2017	Mar. 31, 2017	Jun. 30, 2018
Restructuring Cost And Reserve [Line Items]
Proceeds from sale of property and equipment			$ 25,000			$ 37,000
Gain (loss) on disposal of assets			(9,000)			8,000
Desenzano Del Garada, Italy 3D Printing Operations [Member]
Restructuring Cost And Reserve [Line Items]
Involuntary employee terminations charges				$ 72,000
Total restructuring charges			245,000
Other exit costs			17,000
Asset impairment charges			228,000
Additional charges expected to be incurred			0
Desenzano Del Garada, Italy 3D Printing Operations [Member] | Scenario, Forecast [Member]
Restructuring Cost And Reserve [Line Items]
Additional charges expected to be incurred							$ 11,000
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					$ 32,000	110,000
Total restructuring charges						984,000
Other exit costs						7,000
Asset impairment charges						867,000
Additional charges expected to be incurred			$ 0
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]
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
Direct cost of assets		$ 128,000
Gain (loss) on disposal of assets					(42,000)
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]
Proceeds from sale of property and equipment	$ 1,950,000
Direct cost of assets					$ 347,000
Gain (loss) on disposal of assets	$ 137,000
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
	Mar. 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 R40

Cash, Cash Equivalents, and Restricted Cash - Schedule of Reconciliation of Cash, Cash Equivalents, and Restricted Cash (Detail) - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017	Mar. 31, 2017	Dec. 31, 2016
Cash And Cash Equivalents [Abstract]
Cash and cash equivalents	$ 15,222	$ 21,848
Restricted cash	1,634	330
Cash, cash equivalents, and restricted cash	$ 16,856	$ 22,178	$ 28,334	$ 28,155

Cash, Cash Equivalents, and R41

Cash, Cash Equivalents, and Restricted Cash - Additional Information (Detail) - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017
Cash Cash Equivalents And Restricted Cash [Line Items]
Restricted cash associated with cash collateral	$ 1,634	$ 330
German Bank [Member]
Cash Cash Equivalents And Restricted Cash [Line Items]
Restricted cash associated with cash collateral	1,134
United States Bank [Member]
Cash Cash Equivalents And Restricted Cash [Line Items]
Restricted cash associated with cash collateral	$ 500	$ 330

Inventories - Schedule of Inven

Inventories - Schedule of Inventories (Detail) - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017
Inventory Disclosure [Abstract]
Raw materials and components	$ 8,516	$ 7,171
Work in process	5,254	4,630
Finished goods	4,833	3,629
Inventories	$ 18,603	$ 15,430

Inventories - Additional Inform

Inventories - Additional Information (Detail) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
	Mar. 31, 2018	Dec. 31, 2017
Inventory Disclosure [Abstract]
Allowance for slow-moving and obsolete inventories	$ 3,530	$ 3,437
Inventory (credit) charge	$ (15)	$ 206

Product Warranty Reserves - Add

Product Warranty Reserves - Additional Information (Detail)	3 Months Ended
	Mar. 31, 2018
Product Warranties Disclosures [Abstract]
Standard product warranty period	Substantially all of the Company’s 3D printing machines 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.

Product Warranty Reserves - Sum

Product Warranty Reserves - Summary of Changes in Product Warranty Reserves (Detail) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Guarantees [Abstract]
Balance at beginning of period	$ 1,300	$ 1,115
Provisions for new issuances	219	236
Payments	(208)	(169)
Reserve adjustments	(187)	(150)
Foreign currency translation adjustments	24	12
Balance at end of period	$ 1,148	$ 1,044

Contingencies and Commitments -

Contingencies and Commitments - Additional Information (Detail) - Germany [Member] - German Bank [Member] € in Thousands	3 Months Ended
	Mar. 31, 2018USD ($)	Mar. 31, 2018EUR (€)	Dec. 31, 2017USD ($)	Dec. 31, 2017EUR (€)
Line Of Credit Facility [Line Items]
Credit facility, maximum borrowing capacity	$ 1,600,000	€ 1,300
Credit facility, minimum increments	100,000	100
Credit facility, commitment fee	$ 0
Minimum [Member]
Line Of Credit Facility [Line Items]
Debt Instrument, term	30 days
Commercial Transactions Requiring Security [Member]
Line Of Credit Facility [Line Items]
Credit facility, interest rate	1.75%
Credit facility, outstanding amount	$ 1,134,000	920	$ 1,128,000	€ 941
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	$ 99,000	80
Expiration date, description	June 2,022
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
Short-Term Loans [Member]
Line Of Credit Facility [Line Items]
Outstanding borrowings in form of overdraft credit or short-term loans	0		$ 0
Commercial Transactions Requiring Security Expiring From May Twenty Eighteen Through July Twenty Eighteen [Member]
Line Of Credit Facility [Line Items]
Credit facility, outstanding amount	$ 841,000	682
Expiration date, description	May 2018 through July 2018
Commercial Transactions Requiring Security Without Expiration [Member]
Line Of Credit Facility [Line Items]
Credit facility, outstanding amount	$ 293,000	€ 238

Related Party Revolving Credi47

Related Party Revolving Credit Facility - Additional Information (Detail) - USD ($)	Mar. 12, 2018	Mar. 31, 2018	Mar. 31, 2017
Related Party Transaction [Line Items]
Amortization of debt issuance costs		$ 5,000	$ 2,000
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		172,000
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
Credit facility, expiration date	Mar. 12, 2021
Credit facility, description of variable rate basis	one month LIBOR
Credit facility, interest rate	6.70%	6.90%
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		264,000
Interest expense relating to the Credit Agreement		10,000
Amortization of debt issuance costs		4,000
Debt issuance costs, net		260,000
Interest expense relating to the commitment fee		6,000
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		$ 172,000
Revolving Credit Facility [Member] | LBM Holdings, LLC [Member] | One Month LIBOR [Member]
Related Party Transaction [Line Items]
Credit facility, basis spread on variable rate	5.00%

Income Taxes - Additional Infor

Income Taxes - Additional Information (Detail) - USD ($) $ in Thousands	3 Months Ended		12 Months Ended
	Mar. 31, 2018	Mar. 31, 2017	Dec. 31, 2017
Schedule Of Income Taxes [Line Items]
Provision (benefit) for income taxes	$ 17	$ 0
Effective tax rate	0.30%	0.00%
United States statutory rate	21.00%		34.00%
Liability for uncertain tax positions	$ 883		$ 858
Subsidiaries [Member] | Germany [Member]
Schedule Of Income Taxes [Line Items]
Liability for uncertain tax positions	348		323
Subsidiaries [Member] | Japan [Member]
Schedule Of Income Taxes [Line Items]
Liability for uncertain tax positions	$ 673		$ 594

Equity-Based Compensation - Add

Equity-Based Compensation - Additional Information (Detail) - USD ($)	Jan. 24, 2013	Mar. 31, 2018	Mar. 31, 2017
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation expense		$ 379,000	$ 561,000
Weighted-average remaining vesting period		1 year 3 months 18 days
Intrinsic value, stock options expected to vest		$ 0
Incentive stock options exercised		0	0
Stock Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation expense		$ 203,000	$ 343,000
Total future compensation expense		679,000
Intrinsic value, stock options exercisable		$ 0
Weighted average remaining contractual term of stock options exercisable		6 years 3 months 18 days
Weighted average remaining contractual term of stock options expected to vest		6 years 7 months 6 days
Incentive stock options exercised		0	0
Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation expense		$ 106,000	$ 218,000
Total future compensation expense		384,000
Fair value of restricted shares vested		$ 205,000	$ 299,000
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
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		142,000
Compensation expense, expected to be settled in equity		66,000
2018 Annual Incentive Program [Member] | Cost of Sales [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation expense		21,000
2018 Annual Incentive Program [Member] | Selling, General and Administrative Expenses [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation expense		43,000
2018 Annual Incentive Program [Member] | Research and Development [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation expense		$ 78,000

Equity-Based Compensation - Sum

Equity-Based Compensation - Summary of Total Equity-Based Compensation Expense Recognized for All ISOs, Restricted Stock and Stock Bonus Awards (Detail) - USD ($) $ in Thousands		3 Months Ended
		Mar. 31, 2018	Mar. 31, 2017
Equity-based compensation expense recognized:
Total equity-based compensation expense before income taxes		$ 379	$ 561
Benefit for income taxes	[1]	0	0
Total equity-based compensation expense net of income taxes		379	561
Stock Options [Member]
Equity-based compensation expense recognized:
Total equity-based compensation expense before income taxes		203	343
Restricted Stock [Member]
Equity-based compensation expense recognized:
Total equity-based compensation expense before income taxes		106	218
Other [Member]
Equity-based compensation expense recognized:
Total equity-based compensation expense before income taxes	[2]	$ 70	$ 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 - S51

Equity-Based Compensation - Summary of Total Equity-Based Compensation Expense Recognized for All ISOs, Restricted Stock and Stock Bonus Awards (Parenthetical) (Detail) - USD ($) $ in Thousands		3 Months Ended
		Mar. 31, 2018	Mar. 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	Mar. 16, 2018	Feb. 10, 2017
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted average fair value per stock option	$ 3.77
Volatility	62.58%
Average risk-free interest rate	2.45%
Dividend yield	0.00%	0.00%
Expected term (years)	3 years 3 months 19 days
Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted average fair value per stock option		$ 5.46
Volatility		62.89%
Average risk-free interest rate		1.89%
Expected term (years)		5 years
Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted average fair value per stock option		$ 5.75
Volatility		63.75%
Average risk-free interest rate		1.94%
Expected term (years)		5 years 6 months

Equity-Based Compensation - S53

Equity-Based Compensation - Summary of Activity for Stock Options (Detail) - $ / shares	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Stock options outstanding, Beginning balance	674,470	314,303
Stock options granted	24,000	44,000
Stock options exercised	0	0
Stock options forfeited	(12,500)	(500)
Stock options expired		(666)
Stock options outstanding, Ending balance	685,970	357,137
Stock options exercisable at end of period	424,627	232,471
Stock options expected to vest at end of period	261,343	124,666
Weighted average exercise price, Beginning balance	$ 11.58	$ 15.62
Weighted average exercise price, Stock options granted	8.36	10.10
Weighted average exercise price, Stock options exercised	0	0
Weighted average exercise price, Stock options forfeited	7.91	15.74
Weighted average exercise price, Stock options expired		15.74
Weighted average exercise price, Ending balance	11.53	15.08
Weighted average exercise price, Stock options exercisable	12.93	15.77
Weighted average exercise price, Stock options expected to vest, net of forfeitures	9.25	13.80
Weighted average grant date fair value, Beginning balance	6.41	9.38
Weighted average grant date fair value, Stock options granted	3.77	5.51
Weighted average grant date fair value, Stock options exercised	0	0
Weighted average grant date fair value, Stock options forfeited	3.40	9.60
Weighted average grant date fair value, Stock options expired		9.60
Weighted average grant date fair value, Ending balance	6.37	8.99
Weighted average grant date fair value, Stock options exercisable	7.37	9.47
Weighted average grant date fair value, Stock options expected to vest, net of forfeitures	$ 4.74	$ 8.11

Equity-Based Compensation - S54

Equity-Based Compensation - Summary of Activity for Restricted Stock Awards (Detail) - Restricted Stock [Member] - $ / shares	3 Months Ended
	Mar. 31, 2018	Mar. 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	25,000	30,000
Number of Restricted Shares, vested	(25,000)	(28,834)
Number of Restricted Shares, forfeited	0	0
Number of Restricted Shares, outstanding, Ending Balance	52,502	95,337
Number of Restricted Shares, expected to vest	52,502	95,337
Weighted Average Grant Date Fair Value, Beginning Balance	$ 11.07	$ 14.29
Weighted Average Grant Date Fair Value, granted	8.21	10.10
Weighted Average Grant Date Fair Value, vested	10.10	14.69
Weighted Average Grant Date Fair Value, forfeited	0	0
Weighted Average Grant Date Fair Value, Ending Balance	10.17	12.85
Weighted Average Grant Date Fair Value, expected to vest	$ 10.17	$ 12.85

Fair Value Measurements - Addit

Fair Value Measurements - Additional Information (Detail) - Level 2 Fair Value Measurements [Member] - German Bank [Member] € in Thousands, $ in Thousands	3 Months Ended
	Mar. 31, 2017USD ($)Contract	Mar. 31, 2017EUR (€)Contract	Mar. 31, 2018Contract	Dec. 31, 2017Contract
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Number of foreign exchange forward contracts	2	2	0
Gain realized on settlement of foreign exchange forward contracts	$ 16	€ 15
Number of foreign exchange forward contracts outstanding			0	0
Maximum [Member]
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Unrealized loss on foreign exchange forward contracts	$ 1	€ 1

Fair Value Measurements - Carry

Fair Value Measurements - Carrying Values and Fair Values of Other Financial Instruments (Detail) - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and cash equivalents	$ 15,222	$ 21,848
Restricted cash	1,634	330
Current portion of long-term debt	138	137
Current portion of capital leases	19	15
Long-term debt ̶ net of current portion	1,473	1,508
Capital leases ̶ net of current portion	46	36
Carrying Value [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and cash equivalents	15,222	21,848
Restricted cash	1,634	330
Debt issuance costs	260
Current portion of long-term debt	138	137
Current portion of capital leases	19	15
Long-term debt ̶ net of current portion	1,473	1,508
Capital leases ̶ net of current portion	46	36
Fair Value [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and cash equivalents	15,222	21,848
Restricted cash	1,634	330
Current portion of long-term debt	144	142
Current portion of capital leases	19	15
Long-term debt ̶ net of current portion	1,496	1,533
Capital leases ̶ net of current portion	$ 46	$ 36

Fair Value Measurements - Car57

Fair Value Measurements - Carrying Values and Fair Values of Other Financial Instruments (Parenthetical) (Detail) - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Unamortized debt issuance costs	$ 29	$ 30
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	$ 172

Concentration of Credit Risk -

Concentration of Credit Risk - Additional Information (Detail) - Five Most Significant Customers [Member] - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017	Dec. 31, 2017
Revenue, Major Customer [Line Items]
Accounts receivable from significant customers		$ 1,262	$ 4,199
Customer Concentration Risk [Member] | Sales Revenue, Net [Member]
Revenue, Major Customer [Line Items]
Revenue concentration, by most significant customers	37.20%	40.00%

Related Party Transactions - Ad

Related Party Transactions - Additional Information (Detail) - USD ($)	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017	Dec. 31, 2017
Related Party Transaction [Line Items]
Revenue - related parties	$ 0	$ 8,000
Amounts due from related parties reflected in accounts receivable	0		$ 0
Accounts Payable [Member]
Related Party Transaction [Line Items]
Amounts due to related party	4,000		$ 1,000
Former Chairman and Chief Executive Officer [Member]
Related Party Transaction [Line Items]
Purchases from related parties	$ 6,000	$ 3,000