Represents the base management fees incurred as a percentage of stockholder's equity per annum.

No definition available.

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- Definition

Represents the incentive fee payable on cumulative core earnings that are equal to or less than zero.

+ References

No definition available.

+ Details

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- Definition

Represents the minimum amount of cumulative core earnings which was used to calculate the incentive fee payable.

+ References

No definition available.

+ Details

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- Definition

Related Party Transaction, Minimum Cumulative Core Earnings for Calculation of Incentive Fee, Number of Quarters

+ References

No definition available.

+ Details

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- Definition

Represents the percentage multiplied to arrive at difference of the first value which is affecting calculation of incentive fees.

+ References

No definition available.

+ Details

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- Definition

Represents the percentage multiplied to arrive at the first value which is affecting calculation of incentive fees.

+ References

No definition available.

+ Details

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- Definition

Represents the period whose fiscal quarters is considered to arrive at the first value which is affecting the calculation of incentive fees.

+ References

No definition available.

+ Details

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- Definition

Represents the previous period to calculate the product of weighted average price per share and weighted average number of shares of common stock and other shares.

+ References

No definition available.

+ Details

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- Definition

Represents the previous period for which core earnings are considered to arrive at the first value which is affecting calculation of incentive fees.

+ References

No definition available.

+ Details

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- Definition

Related Party Transactions, Management Fee Look Back Period

+ References

No definition available.

+ Details

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- Definition

Related Party Transactions, Management Fee Renewal Term

+ References

No definition available.

+ Details

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Namespace Prefix:	acre_
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- Definition

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.

+ References

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=120402547&loc=d3e617274-123014

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- Definition

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.

+ 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(c))
-URI http://asc.fasb.org/extlink&oid=120400017&loc=d3e572229-122910

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- Definition

Amount of transactions with related party during the financial reporting period.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 850
-SubTopic 10
-Section 50
-Paragraph 1
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-Topic 850
-SubTopic 10
-Section 50
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=6457730&loc=d3e39603-107864

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Balance Type:	debit
Period Type:	duration

- Definition

Expenses recognized resulting from transactions (excluding transactions that are eliminated in consolidated or combined financial statements) with related party.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 850
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=6457730&loc=d3e39549-107864

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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RELATED PARTY TRANSACTIONS - Narrative (Details)	1 Months Ended	3 Months Ended		9 Months Ended
RELATED PARTY TRANSACTIONS - Narrative (Details)	Jan. 31, 2020 USD ($)	Sep. 30, 2020 USD ($) quarter	Sep. 30, 2019 USD ($)	Sep. 30, 2020 USD ($) quarter	Sep. 30, 2019 USD ($)	Dec. 31, 2019 USD ($)	May 31, 2019 USD ($)
Related Party Transaction [Line Items]
Management fee renewal term				1 year
Management fee look back period				24 months
Loans held for investment		$ 1,778,199,000		$ 1,778,199,000		$ 1,682,498,000
Outstanding principal		1,789,145,000		$ 1,789,145,000		1,692,894,000
ACREM
Related Party Transaction [Line Items]
Base management fees as a percentage of stockholders' equity per annum				1.50%
Incentive fee payable (not less than)		$ 0		$ 0
Percentage multiplied to arrive at first value affecting calculation of incentive fees				20.00%
Previous period for which core earnings are considered to arrive at first value affecting calculation of incentive fees				12 months
Previous period for product of weighted average price per share and weighted average number of shares of common stock and other shares				12 months
Percentage multiplied to arrive at difference of first value affecting calculation of incentive fees				8.00%
Period whose fiscal quarters are considered to arrive at first value affecting calculation of incentive fees				12 months
Minimum cumulative core earnings, number of quarters \| quarter		12		12
Minimum cumulative core earnings for calculation of incentive fee		$ 0		$ 0
Residential
Related Party Transaction [Line Items]
Loans held for investment		44,300,000		44,300,000		$ 40,900,000
Continuing Operations \| ACREM
Related Party Transaction [Line Items]
Incentive fees incurred		2,680,000	$ 2,428,000	8,760,000	$ 7,813,000
Incentive fees \| Continuing Operations \| ACREM
Related Party Transaction [Line Items]
Incentive fees incurred		0	$ 0	303,000	$ 674,000
Senior Mortgage Loans \| Loan Purchase Commitments \| Industrial Property
Related Party Transaction [Line Items]
Outstanding principal							$ 200,000,000
Senior Mortgage Loans \| NORTH CAROLINA \| Loan Purchase Commitments \| Industrial Property
Related Party Transaction [Line Items]
Loan purchased from affiliate	$ 132,600,000
Outstanding principal	$ 107,100,000
Senior Mortgage Loans \| FLORIDA \| Loan Purchase Commitments \| Multifamily
Related Party Transaction [Line Items]
Loan purchased from affiliate				46,700,000
Outstanding principal		$ 46,200,000		$ 46,200,000