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] Manufacturing Equipment [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] Ninebell [Member] Shanghai Zhangjiang Group Co., Ltd. [Member] Subsidies to Polytetrafluoroethylene [Member] Short-term borrowings 9 Equity Components [Axis] Common Stock Class A Common Stock Class B Additional Paid-In Capital Accumulated Deficit Accumulated Other Comprehensive Income Short-term borrowings 10 Short-term borrowings 11 Other [Member] Statement [Table] Statement [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 Emerging Growth Company Entity Ex Transition Period Entity Small Business Entity Current Reporting Status Entity Common Stock, Shares Outstanding Current assets: Cash and cash equivalents Accounts receivable, less allowance for doubtful accounts of $0 as of March 31, 2019 and $0 as of December 31, 2018 (note 3) Other receivables Inventories (note 4) Prepaid expenses Total current assets Property, plant and equipment, net (note 5) Operating lease right-of-use assets, net (note 8) Intangible assets, net Deferred tax assets (note 15) Investment in affiliates, equity method (note 10) Other long-term assets Total assets Liabilities and Stockholders' Equity Current liabilities: Short-term borrowings (note 6) Accounts payable Advances from customers Income tax payable Other payables and accrued expenses (note 7) Current portion of operating lease liability (note 8) Total current liabilities Long-term operating lease liability (note 8) 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 income (loss) Total stockholders' equity Total liabilities and stockholders' equity 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 Income (loss) from operations Interest income Interest expense Other expense, net Equity income in net income of affiliates Income (loss) before income taxes Income tax expense (note 15) Net income (loss) attributable to ACM Research, Inc. Comprehensive income (loss) Net income (loss) Foreign currency translation adjustment Total comprehensive income (loss) (note 2) Net income (loss) per common share (note 2): Basic Diluted Weighted average common shares outstanding used in computing per share amounts (note2): Basic Diluted Beginning balance, shares Beginning balance, amount Net income Exercise of stock option, shares Exercise of stock option, amount Stock-based compensation Exercise of common stock warrant issued to SMC, shares Exercise of common stock warrant issued to SMC, amount Ending balance, shares Ending balance, amount Statement of Cash Flows [Abstract] Cash flows from operating activities: Adjustments to reconcile net income (loss) from operations to net cash used in operating activities: Depreciation and amortization Equity income in net income of affiliates Deferred income taxes Net changes in operating assets and liabilities: Accounts receivable Other receivables Inventory Prepaid expenses Other current assets Accounts payable Advances from customers Income tax payable Other payables and accrued expenses Other long-term liabilities Net cash used in 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 Organization, Consolidation and Presentation of Financial Statements [Abstract] Description of Business Accounting Policies [Abstract] Summary of Significant Accounting Policies Receivables [Abstract] Accounts Receivable Inventory Disclosure [Abstract] Inventories 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 Leases [Abstract] Leases 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 Warrant Liability Warrant Liability 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 Income (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 Lease expense Supplemental cash flow information related to operating lease Maturities of our lease liabilities for all operating leases Weighted average remaining lease terms and discount rates Other long-term liabilities Summary of share option activities Numerator: Denominator: Weighted average shares outstanding, basic Effect of dilutive securities Weighted average shares outstanding, diluted Net income (loss) attributable to ACM 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 Total cost Less: total accumulated depreciation Construction in progress Total property, plant and equipment, net Depreciation expense Short-term borrowings Interest expense related to short-term borrowings Lease expenses and payable for leasehold improvement due to a related party (note 11) Accrued commissions Accrued warranty Accrued payroll Accrued professional fees Accrued machine testing fee Others Total Operating lease cost Short-term lease cost Lease cost Cash paid for amounts included in the measurement of lease liabilities: Operating cash outflow from operating leases Operating cash outflow from operating leases 2019 2020 2021 2022 2023 2024 Total payments Less: interest Present value of lease liabilities Weighted average remaining lease term (years) Weighted average discount rate Other long-term liabilities Purchased materials amount Accounts payable-related party Prepaid for material purchases Leasing expense under lease agreement Lease expenses and payable for leasehold improvement due to a related party 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 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 Statutory U.S federal income tax rate Statutory Chinese income tax rate Income tax provision (benefit) Unrecognized tax benefits Commitments Accrued Machine Testing Fee, Current ACM Shanghai [Member] ACM Wuxi. Document and entity information. Employee and non-employee. 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] 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. 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 Comprehensive Income (Loss), Net of Tax, Attributable to Parent Weighted Average Number of Shares Outstanding, Diluted Shares, Outstanding Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest 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 Increase (Decrease) in Income Taxes Payable, Net of Income Taxes Receivable 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) Warrant Liability [Text Block] Other Noncurrent Liabilities [Table Text Block] Accounts Receivable, Gross, Current Inventory, Gross Accumulated Depreciation, Depletion and Amortization, Property, Plant, and Equipment Operating Lease, Payments Lessee, Operating Lease, Liability, Undiscounted Excess Amount 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