Award Type [Axis] Employee Stock Option [Member] Non Employee Awards [Member] Long-term Debt, Type [Axis] Subsidies to Stress Free Polishing project [Member] Subsidies to Electro Copper Plating project [Member] Property, Plant and Equipment, Type [Axis] Leasehold Improvements [Member] Office Equipment [Member] Transportation Equipment [Member] Tools, Dies and Molds [Member] Investment, Name [Axis] Ninebell [Member] Class of Stock [Axis] Common Class A [Member] Common Class B [Member] Range [Axis] Maximum [Member] Minimum [Member] Short-term Debt, Type [Axis] Short-term borrowings 1 Short-term borrowings 2 Short-term borrowings 3 Short-term borrowings 4 Short-term borrowings 5 Short-term borrowings 6 Short-term borrowings 7 Short-term borrowings 8 Related Party [Axis] Shanghai Zhangjiang Group Co., Ltd. [Member] Document Information [Table] Document Information [Line Items] Document Type Amendment Flag Document Period End Date Document Fiscal Year Focus Document Fiscal Period Focus Trading Symbol Entity Registrant Name Entity Central Index Key Current Fiscal Year End Date Entity Filer Category Entity Well-known Seasoned Issuer Entity Voluntary Filers Entity Current Reporting Status Entity Common Stock, Shares Outstanding Statement [Table] Statement [Line Items] Current assets: Cash and cash equivalents Accounts receivable, less allowance for doubtful accounts of $ nil as of March 31, 2018 and $ nil as of December 31, 2017 (note 3) Other receivables Inventory (note 4) Prepaid expenses Other current assets Total current assets Property, plant and equipment, net (note 5) Intangible assets, net Deferred tax assets (note 15) Investment in affiliates, equity method (note 10) Total assets Liabilities and Stockholders’ Equity Current liabilities: Short-term borrowings (note 6) Warrant liability (note 8) Accounts payable Advances from customers Income tax payable Other payables and accrued expenses (note 7) Total current liabilities Other long-term liabilities (note 9) Total liabilities Commitments and contingencies (note 16) Stockholders' equity (deficit): Common stock Additional paid in capital Accumulated deficit Accumulated other comprehensive loss Total stockholders’ equity Total liabilities and stockholders’ equity Scenario [Axis] Accounts receivable, allowance for doubtful accounts Common stock, par value Common stock, shares authorized Common stock, shares issued Common stock, shares outstanding Income Statement [Abstract] Revenue Cost of revenue Gross profit Operating expenses: Sales and marketing Research and development General and administrative Total operating expenses, net Loss from operations Interest income Interest expense Other expense, net Equity in net income of affiliates Loss before income taxes Income tax expense (note 15) Net loss Less: Net loss attributable to non-controlling interests Net loss attributable to ACM Research, Inc. Comprehensive loss: Net loss Foreign currency translation adjustment Comprehensive loss Less: Comprehensive loss attributable to non-controlling interests Total comprehensive loss attributable to ACM Research, Inc. (note 2) Net loss per common share (note 2): Basic Diluted Weighted-average common shares outstanding used in computing per share amounts (note 2): Basic Diluted Investment Company, Capital Share Transactions [Abstract] Cash flows from operating activities: Adjustments to reconcile net loss from operations to net cash provided by operating activities: Depreciation and amortization Undistributed earnings from investments in equity method affiliates Deferred income taxes Stock-based compensation Net changes in operating assets and liabilities: Accounts receivable Other receivables Inventory Prepaid expenses Other current assets Accounts payable Advances from customers Other payables and accrued expenses Other long-term liabilities Net cash (used in) provided by operating activities Cash flows from investing activities: Purchase of property and equipment Purchase of intangible assets Net cash used in investing activities Cash flows from financing activities: Proceeds from short-term borrowings Repayments of short-term borrowings Proceeds from stock option exercise to common stock Net cash provided by financing activities Effect of exchange rate changes on cash and cash equivalents Net (decrease) increase in cash and cash equivalents Cash and cash equivalents at beginning of period Cash and cash equivalents at end of period Supplemental disclosure of cash flow information: Interest paid Accounting Policies [Abstract] Description of Business Summary of Significant Accounting Policies Receivables [Abstract] Accounts Receivable Inventory Disclosure [Abstract] Inventory Property, Plant and Equipment [Abstract] Property, Plant and Equipment, Net Debt Disclosure [Abstract] Short-Term Borrowings Payables and Accruals [Abstract] Other Payable and Accrued Expenses Text Block [Abstract] Warrant Liability Other Liabilities Disclosure [Abstract] Other Long-Term Liabilities Equity Method Investments and Joint Ventures [Abstract] Equity Method Investment Related Party Transactions [Abstract] Related Party Balances and Transactions Leases [Abstract] Leases Equity [Abstract] Common Stock Disclosure of Compensation Related Costs, Share-based Payments [Abstract] Stock-Based Compensation Income Tax Disclosure [Abstract] Income Taxes Commitments and Contingencies Disclosure [Abstract] Commitments and Contingencies Basis of Presentation and Principles of Consolidation Use of Estimates Basic and Diluted Net Loss per Common Share Recent Accounting Pronouncements Calculation of basic and diluted net loss per common share Accounts receivable Inventory Property, plant and equipment Short-term borrowings Other payable and accrued expenses Other long-term liabilities Summary of future minimum lease payments under non-cancelable lease agreements Summary of share option activities Summary of assumptions used to determine fair value of share options granted Earnings Per Share [Abstract] Numerator: Net income (loss) Net income (loss) attributable to non-controlling interest Net loss available to common stockholders, basic and diluted Denominator: Weighted average shares outstanding, basic Effect of dilutive securities Weighted average shares outstanding, diluted Net loss per common share: Accounts receivable Less: Allowance for doubtful accounts Total Allowance for doubtful accounts Accounts receivable were pledged as collateral for borrowings Raw materials Work in process Finished goods Total inventory, gross Inventory reserve Total inventory, net Inventory reserve Inventory pledged as collateral for borrowings Property, Plant and Equipment [Table] Property, Plant and Equipment [Line Items] Total cost Less: Total accumulated depreciation Construction in progress Total property, plant and equipment, net Property Plant And Equipment Capitalized Interest Costs [Abstract] Depreciation expense Schedule of Short-term Debt [Table] Short-term Debt [Line Items] Short-term borrowings Interest expense related to short-term borrowings Lease expenses and payable for leasehold improvement due to a related party (note 11) Commissions Accrued warranty Accrued payroll Accrued professional fees Accrued machine testing fee Others Total Other Long Term Liabilities [Table] Other Long Term Liabilities [Line Items] Other long-term liabilities Undistributed earnings attributable to ACM's equity method investment Schedule of Related Party Transactions, by Related Party [Table] Related Party Transaction [Line Items] Purchased materials amount Accounts payable-related party Leasing expense under lease agreement Lease expenses and payable for leasehold improvement due to a related party Operating Leases, Future Minimum Payments Receivable [Abstract] 2018 2019 2020 2021 2022 Total Rent expense Schedule of Stock by Class [Table] Class of Stock [Line Items] Consolidated Entities [Axis] Title of Individual [Axis] Legal Entity [Axis] Shares of common stock issued for stock option exercises Schedule of Share-based Compensation Arrangements by Share-based Payment Award [Table] Share-based Compensation Arrangement by Share-based Payment Award [Line Items] Number of Option Shares, Outstanding, Beginning balance Number of Option Shares, Outstanding, Granted Number of Option Shares, Outstanding, Exercised Number of Option Shares, Outstanding, Expired Number of Option Shares, Outstanding, Forfeited Number of Option Shares, Outstanding, Ending balance Vested and exercisable Weighted Average Grant Date Fair Value, Outstanding, Beginning balance Weighted Average Grant Date Fair Value, Granted Weighted Average Grant Date Fair Value, Exercised Weighted Average Grant Date Fair Value, Expired Weighted Average Grant Date Fair Value, Forfeited Weighted Average Grant Date Fair Value, Outstanding, Ending balance Weighted Average Exercise Price, Outstanding, Beginning balance Weighted Average Exercise Price, Granted Weighted Average Exercise Price, Exercised Weighted Average Exercise Price, Expired Weighted Average Exercise Price, Forfeited Weighted Average Exercise Price, Outstanding, Ending balance Weighted Average Remaining Contractual Term, Outstanding Fair value of common share Expected term in years Volatility Risk-free interest rate Expected dividend Stock-based compensation expense Unrecognized employee stock-based compensation expense, net of estimated forfeitures Weighted-average period over which unrecognized compensation is expected to be recognized Number of options granted Income Taxes [Table] Income Taxes [Line Items] Tax Period [Axis] Statutory U.S federal income tax rate Statutory Chinese income tax rate Income tax provision (benefit) Unrecognized tax benefits Accrued Machine Testing Fee, Current ACM Shanghai [Member] ACM Wuxi. Document and entity information. Employee and non-employee. Line items represent disclosure of income taxes. Income Taxes [Table] Inventory Pledged As Collateral Line of credit Five Point Six Nine Percent due March Five Twenty Eighteen [Member] Line of credit Five Point Six Six Percent due July Three Twenty Seventeen [Member] Line of credit Five Point Six Six Percent due September Twenty Three Twenty Eighteen [Member] Line of credit Five Point Six Six Percent due September Twenty Two Twenty Eighteen [Member] Line of credit Three Point Two Percent due July Three Twenty Seventeen [Member] Loan agreement. Ninebel. Non-employee awards. Operating Lease Agreement [Member] Other Long Term Liabilities [Line Items] Other Long Term Liabilities [Table] Property Plant And Equipment Capitalized Interest Costs [Abstract] Series A Convertible Preferred Stock. Series B Convertible Preferred Stock. Series C Convertible Preferred Stock. Series D Convertible Preferred Stock. Series E Convertible Preferred Stock. Series F Convertible Preferred Stock. Shanghai Zhangjiang Group Co., Ltd. Share based compensation arrangement by share based payment award options exercised in period weighted average grant date fair value. Share based compensation arrangement by share based payment award options expired in period weighted average grant date fair value. Share based compensation arrangement by share based payment award options forfeited in period weighted average grant date fair value. Share based compensation arrangement by share based payment award options outstanding in period weighted average grant date fair value. Share-based Compensation Arrangement by Share-based Payment Award, Options Outstanding, Weighted Average Exercise Price, and Additional Disclosures [Abstract] Shengxin (Shanghai) Management Consulting Limited Partnership. Short-Term Borrowings Due February Ten Twenty Seventeen [Member] Short-Term Borrowings Due June Twenty Four Twenty Seventeen [Member] Subsidies to Electro Copper Plating project [Member] Subsidies to Patent project [Member] Subsidies to Stress Free Polishing project [Member] Warrant Liability [Text Block] Assets, Current Assets Liabilities, Current Liabilities Stockholders' Equity Attributable to Parent Liabilities and Equity Gross Profit Operating Expenses Operating Income (Loss) Interest Expense Income (Loss) from Continuing Operations before Income Taxes, Noncontrolling Interest Net Income (Loss) Attributable to Parent Comprehensive Income (Loss), Net of Tax, Including Portion Attributable to Noncontrolling Interest Comprehensive Income (Loss), Net of Tax, Attributable to Parent Weighted Average Number of Shares Outstanding, Diluted Increase (Decrease) in Receivables Increase (Decrease) in Other Receivables Increase (Decrease) in Inventories Increase (Decrease) in Prepaid Expense Increase (Decrease) in Other Current Assets Increase (Decrease) in Accounts Payable Increase (Decrease) in Customer Advances Net Cash Provided by (Used in) Operating Activities, Continuing Operations Payments to Acquire Property, Plant, and Equipment Payments to Acquire Intangible Assets Net Cash Provided by (Used in) Investing Activities, Continuing Operations Repayments of Short-term Debt Net Cash Provided by (Used in) Financing Activities, Continuing Operations Cash and Cash Equivalents, Period Increase (Decrease) Schedule of Inventory, Current [Table Text Block] Other Noncurrent Liabilities [Table Text Block] Net Income (Loss) Available to Common Stockholders, Basic Accounts Receivable, Gross, Current Inventory, Gross Accumulated Depreciation, Depletion and Amortization, Property, Plant, and Equipment Operating Leases, Future Minimum Payments Due Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number Share-based Compensation Arrangement by Share-based Payment Award, Options, Expirations in Period Share-based Compensation Arrangement by Share-based Payment Award, Options, Forfeitures in Period Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding In Period Weighted Average Grant Date Fair Value Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price