Summary of Significant Accounting Policies | Basis of Presentation and Principles of Consolidation The consolidated accounts include ACM and its subsidiaries ACM Shanghai, ACM Wuxi, CleanChip and ACM Korea. Subsidiaries are those entities in which ACM, directly and indirectly, controls more than one half of the voting power. All significant intercompany transactions and balances have been eliminated upon consolidation. The accompanying condensed consolidated financial statements of the Company have been prepared in accordance with accounting principles generally accepted in the United States of America (“GAAP”) for interim financial information and the rules and regulations of the SEC for reporting on Form 10-Q. Accordingly, they do not include all the information and footnotes required by GAAP for complete financial statements herein. The unaudited condensed consolidated financial statements herein should be read in conjunction with the historical consolidated financial statements of the Company for the year ended December 31, 2018 included in the Company’s Annual Report on Form 10-K for the year ended December 31, 2018. The accompanying condensed consolidated balance sheet as of June 30, 2019, the condensed consolidated statements of operations and comprehensive income for the three and six months ended June 30, 2019 and 2018, the condensed consolidated statements of changes in stockholders’ equity for the six months ended June 30, 2019 and 2018, and the condensed consolidated statements of cash flows for the six months ended June 30, 2019 and 2018 are unaudited. In the opinion of management, the unaudited condensed consolidated financial statements of the Company reflect all adjustments that are necessary for a fair presentation of the Company’s financial position and results of operations. Such adjustments are of a normal recurring nature, unless otherwise noted. The balance sheet as of June 30, 2019 and the results of operations for the three and six months ended June 30, 2019 are not necessarily indicative of the results to be expected for any future period. Use of Estimates The preparation of condensed consolidated financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the balance sheet date and the reported revenue and expenses during the reported period in the condensed consolidated financial statements and accompanying notes. The Company’s significant accounting estimates and assumptions include, but are not limited to, those used for the valuation and recognition of stock-based compensation arrangements and warrant liability, realization of deferred tax assets, assessment for impairment of long-lived assets, allowance for doubtful accounts, inventory valuation for excess and obsolete inventories, lower of cost and market value or net realizable value of inventories, depreciable lives of property and equipment, and useful life of intangible assets. Management of the Company believes that the estimates, judgments and assumptions are reasonable, based on information available at the time they are made. Actual results could differ materially from those estimates. Basic and Diluted Net Income per Common Share Basic and diluted net income per common share is calculated as follows: Three Months Ended June 30, Six Months Ended June 30, 2019 2018 2019 2018 Numerator: Net income $ 4,311 $ 3,215 $ 6,168 $ 435 Denominator: Weighted average shares outstanding, basic 16,090,937 15,838,540 16,067,924 15,611,863 Effect of dilutive securities 2,513,410 2,281,193 2,387,610 2,057,787 Weighted average shares outstanding, diluted 18,604,347 18,119,733 18,455,534 17,669,650 Net income per common share: Basic $ 0.27 $ 0.20 $ 0.38 $ 0.03 Diluted $ 0.23 $ 0.18 $ 0.33 $ 0.02 ACM has been authorized to issue Class A and Class B common stock since redomesticating in Delaware in November 2016. The two classes of common stock are substantially identical in all material respects, except for voting rights. Since ACM did not declare any dividends during the three and six months ended June 30, 2019 and 2018, the net income per common share attributable to each class is the same under the “two-class” method. As such, the two classes of common stock have been presented on a combined basis in the condensed consolidated statements of operations and comprehensive income and in the above computation of net income per common share. Diluted net income per common share reflects the potential dilution from securities that could share in ACM’s earnings. ACM’s potential dilutive securities consist warrants and stock options for the three and six months ended June 30, 2019 and 2018. Certain potential dilutive securities were excluded from the net income per share calculation because the impact would be anti-dilutive. Recent Accounting Pronouncements Recently Adopted Accounting Pronouncements In February 2016, the Financial Accounting Standards Board (“FASB”) issued Accounting Standards Update (“ASU”) 2016-02, Leases (Topic 842) Leases Leases Effective January 1, 2019, the Company adopted ASU 2016-02. The original guidance required application on a modified retrospective basis with the earliest period presented. In August 2018, the FASB issued ASU 2018-11, Targeted Improvements to ASC 842 Leases In June 2018, the FASB issued ASU 2018-07, Compensation—Stock Compensation (Topic 718)—Improvements to Nonemployee Share-Based Payment Accounting Compensation—Stock Compensation Revenue from Contracts with Customers (Topic 606) Recent Accounting Pronouncements Not Yet Adopted In August 2018, the FASB issued ASU 2018-13, Fair Value Measurement (Topic 820) In January 2017, the FASB issued ASU 2017-04, Intangibles—Goodwill and Other (Topic 350): Simplifying the Test for Goodwill Impairment In June 2016, the FASB issued ASU 2016-13, Financial Instruments-Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments |