No definition available.

Name:	acmr_ClassificationOfInvestmentsAbstract
Namespace Prefix:	acmr_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

The amount of investment in partnership.

+ References

No definition available.

+ Details

Name:	acmr_InvestmentInPartnership
Namespace Prefix:	acmr_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

The number of investors with agreements entered pursuant to qualifying for the Listing and IPO.

+ References

No definition available.

+ Details

Name:	acmr_NumberOfInvestorsWithAgreementsEntered
Namespace Prefix:	acmr_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

The percentage ownership in Partnership's total subscribed capital.

+ References

No definition available.

+ Details

Name:	acmr_OwnershipPercentageInPartnership
Namespace Prefix:	acmr_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

This element represents the aggregate cost of investments accounted for under the equity method of accounting.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.12)
-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

+ Details

Name:	us-gaap_EquityMethodInvestmentAggregateCost
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 323
-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=114001798&loc=d3e33918-111571

+ Details

Name:	us-gaap_EquityMethodInvestmentOwnershipPercentage
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

This item represents the carrying amount on the entity's balance sheet of its investment in common stock of an equity method investee. This is not an indicator of the fair value of the investment, rather it is the initial cost adjusted for the entity's share of earnings and losses of the investee, adjusted for any distributions (dividends) and other than temporary impairment (OTTI) losses recognized.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 323
-SubTopic 10
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=109237563&loc=d3e33749-111570

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 25
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=120311839&loc=d3e8813-108599

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-Publisher FASB
-Name Accounting Standards Codification
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-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.12)
-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

+ Details

Name:	us-gaap_EquityMethodInvestments
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Sum of the carrying amounts as of the balance sheet date of all investments.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03.1(h))
-URI http://asc.fasb.org/extlink&oid=120400017&loc=d3e572229-122910

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Name:	us-gaap_Investments
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- References

No definition available.

+ Details

Name:	us-gaap_InvestmentsAbstract
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Number of shares of stock issued as of the balance sheet date, including shares that had been issued and were previously outstanding but which are now held in the treasury.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=109259400&loc=d3e21463-112644

+ Details

Name:	us-gaap_SharesIssued
Namespace Prefix:	us-gaap_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	instant

- Definition

Per share or per unit amount of equity securities issued.

+ References

No definition available.

+ Details

Name:	us-gaap_SharesIssuedPricePerShare
Namespace Prefix:	us-gaap_
Data Type:	num:perShareItemType
Balance Type:	na
Period Type:	instant

- Details

Name:	us-gaap_RelatedPartyTransactionsByRelatedPartyAxis=acmr_NinebellCompanyLimitedMember
Namespace Prefix:
Data Type:	na
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Period Type:

- Details

Name:	us-gaap_StatementClassOfStockAxis=us-gaap_CommonClassAMember
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- Details

Name:	us-gaap_RelatedPartyTransactionsByRelatedPartyAxis=acmr_ShengyiSemiconductorTechnologyCompanyLimitedMember
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- Details

Name:	us-gaap_RelatedPartyTransactionsByRelatedPartyAxis=acmr_HefeiShixiChanhengIntegratedCircuitIndustryVentureCapitalFundPartnershipMember
Namespace Prefix:
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LONG TERM INVESTMENTS (Details) $ / shares in Units, $ in Thousands	Sep. 05, 2019 shares	Sep. 30, 2020 USD ($)	Dec. 31, 2019 USD ($)	Sep. 30, 2019 USD ($)	Jun. 27, 2019 USD ($)	Sep. 11, 2017 USD ($) $ / shares shares
Classification of Investments [Abstract]
Total		$ 6,580	$ 5,934
Ninebell [Member]
Investments [Abstract]
Percentage of ordinary shares issued						20.00%
Purchase price						$ 1,200
Classification of Investments [Abstract]
Total		2,088	1,538
Ninebell [Member] \| Class A Common Stock [Member]
Investments [Abstract]
Purchase price						$ 1,000
Shares issued (in shares) \| shares						133,334
Share price (in dollars per share) \| $ / shares						$ 7.50
Shengyi [Member]
Investments [Abstract]
Percentage of ordinary shares issued					15.00%
Investment - equity method					$ 109
Number of investors with agreements entered \| shares	6
Classification of Investments [Abstract]
Total		134	107
Hefei Shixi [Member]
Investments [Abstract]
Investment in partnership				$ 4,200
Ownership percentage in partnership				10.00%
Classification of Investments [Abstract]
Total		$ 4,358	$ 4,289