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

Financing Receivable, Cost Recovery, Interest Received

No definition available.

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

Financing Receivable, Cost Recovery, Net

No definition available.

Name:	ari_FinancingReceivableCostRecoveryNet
Namespace Prefix:	ari_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

Financing Receivable, Loan Specific, Credit Loss, Expense (Reversal)

No definition available.

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

Guarantor Obligations, Maximum Exposure, Term

No definition available.

Name:	ari_GuarantorObligationsMaximumExposureTerm
Namespace Prefix:	ari_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

Mortgage Loans on Real Estate, Commercial and Consumer, Percentage of Portfolio

No definition available.

Name:	ari_MortgageLoansOnRealEstateCommercialAndConsumerPercentageOfPortfolio
Namespace Prefix:	ari_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

Proceeds From Pre-payment Penalties

No definition available.

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

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.

No definition available.

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

Maximum potential amount of future payments (undiscounted) the guarantor could be required to make under the guarantee or each group of similar guarantees before reduction for potential recoveries under recourse or collateralization provisions.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 460
-SubTopic 10
-Section 50
-Paragraph 4
-Subparagraph (b)(1)
-URI http://asc.fasb.org/extlink&oid=124440162&loc=d3e12069-110248

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

Carrying amount as of the balance sheet date of interest earned but not received. Also called accrued interest or accrued interest receivable.

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 210.5-02.8)
-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

Name:	us-gaap_InterestReceivable
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
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=120400017&loc=d3e572229-122910

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

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.

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 http://asc.fasb.org/extlink&oid=123570139&loc=d3e3602-108585

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

Name:	us-gaap_FinancingReceivablePortfolioSegmentAxis=ari_CommercialMortgageandSubordinatedPortfolioSegmentMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Name:	us-gaap_FinancingReceivablePortfolioSegmentAxis=ari_SubordinateMortgagePortfolioSegmentMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Name:	srt_MortgageLoansOnRealEstateDescriptionTypeOfPropertyAxis=ari_UrbanRetailMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Name:	us-gaap_FinancingReceivablesPeriodPastDueAxis=us-gaap_FinancingReceivablesEqualToGreaterThan90DaysPastDueMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Name:	us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis=ari_FloatingRateLoanMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Name:	us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis=ari_MezzanineLoansMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Name:	us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis=ari_SeniorMezzanineLoansMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Name:	us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis=ari_JuniorMezzanineALoanMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: