Name:	acre_DebtInstrumentMaturityDateLengthOfExtensionPeriod
Namespace Prefix:	acre_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

The number of times which the maturity date of the secured credit facility can be extended.

No definition available.

Name:	acre_LineOfCreditFacilityNumberOfExtensions
Namespace Prefix:	acre_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant

Amount of contractual principal due at origination of mortgage loan within investment in mortgage loan on real estate by entity with substantial portion of business acquiring and holding investment real estate or interest in real estate.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 12
-Paragraph Column F
-Subsection 29

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 948
-SubTopic 310
-Section S99
-Paragraph 1
-Subparagraph (SX 210.12-29(Column F))
-URI http://asc.fasb.org/extlink&oid=6589523&loc=d3e617274-123014

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

Aggregate dividends declared during the period for each share of common stock outstanding.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.3-04)
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Face amount or stated value per share of common stock.

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Percentage points added to the reference rate to compute the variable rate on the debt instrument.

No definition available.

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Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

No definition available.

Name:	us-gaap_DebtInstrumentTerm
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Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

The percentage points (also referred to as 'margin') added to the reference rate as stated in the loan agreement and used to compute the variable rate on the loans receivable. For instance, the loan agreement might state that the interest rate the borrower is obligated to pay is the London Interbank Offered Rate (LIBOR) plus three quarters (3/4) of a percentage point adjusted quarterly (each three months). LIBOR in this example is the index or reference rate, 3/4 percentage point is the margin, the reference rate plus the margin is the fully indexed rate. This element would be used to report separately the margin.

No definition available.

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

The balance represents the amount of loans that are secured by real estate mortgages, offset by the reserve to cover probable credit losses on the loan portfolio.

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(c))
-URI http://asc.fasb.org/extlink&oid=119400593&loc=d3e572229-122910

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

The cash inflow from the additional capital contribution to the entity.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 14
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=118932676&loc=d3e3255-108585

Name:	us-gaap_ProceedsFromIssuanceOfCommonStock
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

Number of new stock issued during the period.

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(29))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: 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

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-Name Accounting Standards Codification
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Name:	us-gaap_StockIssuedDuringPeriodSharesNewIssues
Namespace Prefix:	us-gaap_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration

Detail information of subsequent event by type. User is expected to use existing line items from elsewhere in the taxonomy as the primary line items for this disclosure, which is further associated with dimension and member elements pertaining to a subsequent event.

No definition available.

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

Name:	us-gaap_SubsequentEventTypeAxis=us-gaap_SubsequentEventMember
Namespace Prefix:
Data Type:	na
Balance Type:
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Name:	us-gaap_LineOfCreditFacilityAxis=acre_MorganStanleyBankN.A.Member
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Name:	us-gaap_DebtInstrumentAxis=acre_RevolvingMasterRepurchaseFacilityMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Name:	us-gaap_VariableRateAxis=acre_DebtInstrumentVariableRateBaseLIBOROneMonthMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Name:	srt_StatementGeographicalAxis=acre_DiversifiedPropertiesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Name:	srt_MortgageLoansOnRealEstateLoanTypeAxis=acre_SeniorMortgageLoansMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Name:	srt_MortgageLoansOnRealEstateDescriptionTypeOfPropertyAxis=srt_OfficeBuildingMember
Namespace Prefix:
Data Type:	na
Balance Type:
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Name:	us-gaap_DebtInstrumentAxis=acre_LIBORPlus3Point65PercentDueJanuary2023Member
Namespace Prefix:
Data Type:	na
Balance Type:
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Name:	us-gaap_VariableRateAxis=us-gaap_LondonInterbankOfferedRateLIBORMember
Namespace Prefix:
Data Type:	na
Balance Type:
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Name:	srt_StatementGeographicalAxis=stpr_TX
Namespace Prefix:
Data Type:	na
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Name:	srt_MortgageLoansOnRealEstateDescriptionTypeOfPropertyAxis=srt_MultifamilyMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Name:	us-gaap_DebtInstrumentAxis=acre_LIBORPlus3Point25PercentDueJanuary2023Member
Namespace Prefix:
Data Type:	na
Balance Type:
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Name:	srt_StatementGeographicalAxis=stpr_NY
Namespace Prefix:
Data Type:	na
Balance Type:
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Name:	srt_MortgageLoansOnRealEstateDescriptionTypeOfPropertyAxis=srt_IndustrialPropertyMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Name:	us-gaap_DebtInstrumentAxis=acre_LIBORPlus5Point00PercentDueJanuary2021Member
Namespace Prefix:
Data Type:	na
Balance Type:
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Name:	srt_StatementGeographicalAxis=stpr_WA
Namespace Prefix:
Data Type:	na
Balance Type:
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Name:	us-gaap_DebtInstrumentAxis=acre_LIBORPlus3Point00PercentDueJanuary2023Member
Namespace Prefix:
Data Type:	na
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Name:	us-gaap_StatementClassOfStockAxis=us-gaap_CommonStockMember
Namespace Prefix:
Data Type:	na
Balance Type:
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Name:	us-gaap_SubsidiarySaleOfStockAxis=us-gaap_OverAllotmentOptionMember
Namespace Prefix:
Data Type:	na
Balance Type:
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Name:	srt_RangeAxis=srt_MinimumMember
Namespace Prefix:
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