Debt Instrument, Decrease In Participating Interest

No definition available.

Name:	ari_DebtInstrumentDecreaseInParticipatingInterest
Namespace Prefix:	ari_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Debt Instrument, Remaining Unfunded Commitment

+ References

No definition available.

+ Details

Name:	ari_DebtInstrumentRemainingUnfundedCommitment
Namespace Prefix:	ari_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Participating Mortgage Loans, Participation Liabilities, Amount Increase (Decrease)

+ References

No definition available.

+ Details

Name:	ari_ParticipatingMortgageLoansParticipationLiabilitiesAmountIncreaseDecrease
Namespace Prefix:	ari_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Face (par) amount of debt instrument at time of issuance.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 1B
-Subparagraph (a)
-URI https://asc.fasb.org/extlink&oid=123466505&loc=SL123495323-112611

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
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-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 55
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-URI https://asc.fasb.org/extlink&oid=114775985&loc=d3e28878-108400

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 50
-Paragraph 1
-URI https://asc.fasb.org/extlink&oid=124429444&loc=SL124452920-239629

Reference 5: http://www.xbrl.org/2003/role/exampleRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 55
-Paragraph 69C
-URI https://asc.fasb.org/extlink&oid=123466577&loc=SL123495737-112612

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 55
-Paragraph 69B
-URI https://asc.fasb.org/extlink&oid=123466577&loc=SL123495735-112612

+ Details

Name:	us-gaap_DebtInstrumentFaceAmount
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- 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 https://asc.fasb.org/extlink&oid=126734703&loc=d3e572229-122910

+ Details

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

- Definition

Interest paid other than in cash for example by issuing additional debt securities. As a noncash item, it is added to net income when calculating cash provided by or used in operations using the indirect method.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI https://asc.fasb.org/extlink&oid=126954810&loc=d3e3602-108585

+ Details

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

- 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

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

- Details

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Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_CreditFacilityAxis=us-gaap_SecuredDebtMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis=ari_GroundUpCondominiumDevelopmentNewYorkMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis=ari_OfficeBuildingLondonMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Participations Sold (Details) $ in Thousands, £ in Millions	1 Months Ended	3 Months Ended		12 Months Ended
Participations Sold (Details) $ in Thousands, £ in Millions	Jun. 30, 2021 USD ($)	Dec. 31, 2022 USD ($)	Dec. 31, 2021 USD ($)	Dec. 31, 2022 USD ($)	Dec. 31, 2020 USD ($)	Dec. 31, 2020 GBP (£)	Oct. 31, 2020 USD ($)	Jan. 31, 2020 USD ($)	Jan. 31, 2020 GBP (£)
Participating Mortgage Loans [Line Items]
Payment in kind interest		$ 10,000	$ 47,700	$ 46,700
Total carrying value, net		$ 8,681,990	$ 7,857,260	8,681,990
Participating mortgage loans, participation liabilities, amount decrease				$ 1,900
Mezzanine Loans
Participating Mortgage Loans [Line Items]
Debt instrument, decrease in participating interest	$ 27,700
Payment in kind interest	$ 2,700
Mezzanine Loans \| Secured Debt
Participating Mortgage Loans [Line Items]
Total carrying value, net					$ 88,100	£ 72.9
Mezzanine Loans \| Ground-up Condominium Development - New York
Participating Mortgage Loans [Line Items]
Debt instrument, face amount							$ 25,000
Mezzanine Loans \| Office Building - London
Participating Mortgage Loans [Line Items]
Debt instrument, face amount					8,900	6.7		$ 81,300	£ 62.2
Remaining unfunded commitment					$ 25,300	£ 19.1		$ 65,300	£ 50.0