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

No definition available.

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- Definition

Loan and Leases Receivable, Deferred income [Roll Forward]

+ References

No definition available.

+ Details

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- Definition

Loan and Leases Receivable, Gross [Roll Forward]

+ References

No definition available.

+ Details

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- Definition

Loan and Leases Receivable, Net [Roll Forward]

+ References

No definition available.

+ Details

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- Definition

Loans and Leases Receivable, Deferred Income, Gain (Loss) On Sale

+ References

No definition available.

+ Details

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Balance Type:	credit
Period Type:	duration

- Definition

Loans and Leases Receivable, Gain (Loss) on Sales, Gross

+ References

No definition available.

+ Details

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Balance Type:	credit
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- Definition

Loans and Leases Receivable, Net, Realized Gain (Loss) On Investment

+ References

No definition available.

+ Details

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- Definition

Loans and Leases Receivable, Deferred Income, Amortization

+ References

No definition available.

+ Details

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- Definition

Loans and Leases Receivable, Deferred Income, Period Increase

+ References

No definition available.

+ Details

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- Definition

Loans and Leases Receivable, Deferred Income, Unamortized Loan Commitment and Origination Fees, and Unamortized Discounts or Premiums, Period Increase

+ References

No definition available.

+ Details

Name:	ari_LoansandLeasesReceivableDeferredIncomeUnamortizedLoanCommitmentandOriginationFeesandUnamortizedDiscountsorPremiumsPeriodIncrease
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Balance Type:	credit
Period Type:	duration

- Definition

Loans and Leases Receivable, Deferred Income, Unrealized Gain On Foreign Currency Translation

+ References

No definition available.

+ Details

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- Definition

Loans and Leases Receivable, Gross, Foreign Currency Gain (Loss)

+ References

No definition available.

+ Details

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- Definition

Loans and Leases Receivable, Gross, Paid-in-Kind Interest, Loan Commitment and Origination Fees, and Discounts or Premiums, Amortization

+ References

No definition available.

+ Details

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- Definition

Loans and Leases Receivable, Net, Deferred Income, PIK Interest, Loan Commitment and Origination Fees, and Discounts or Premiums, Amortization

+ References

No definition available.

+ Details

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- Definition

Loans and Leases Receivable, Net, Foreign Currency Gain (Loss)

+ References

No definition available.

+ Details

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- Definition

Mortgage Loans on Real Estate, Commercial and Consumer And Financing Receivable, Net

+ References

No definition available.

+ Details

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- Definition

Off-Balance-Sheet, Credit Loss, Liability, Amount Excluded

+ References

No definition available.

+ Details

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

Payments to Purchase Loans Held-for-sale, Add-on Funding

+ References

No definition available.

+ Details

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

- Definition

The reserve to cover probable credit losses related to specifically identified fixed maturity real estate loans as well as probable credit losses inherent in the remainder of that loan portfolio.

+ References

No definition available.

+ Details

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Period Type:	instant

- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

No definition available.

+ Details

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- Definition

Amount excluding accrued interest, of allowance for credit loss on financing receivable. Excludes net investment in lease.

+ References

+ Details

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- Definition

Amount of fee received for commitment to originate or purchase financing receivable where likelihood of commitment being exercised is remote, to be recognized as service income.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 310
-SubTopic 20
-Name Accounting Standards Codification
-Section 45
-Paragraph 2
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481598/310-20-45-2

+ Details

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Balance Type:	credit
Period Type:	instant

- Definition

Amortized cost excluding accrued interest, after allowance for credit loss, of financing receivable. Excludes net investment in lease.

+ References

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
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Period Type:	instant

- Definition

Amortized cost excluding accrued interest, before allowance for credit loss, of financing receivable. Excludes net investment in lease.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 45
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479344/326-20-45-1

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 3B
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479319/326-20-50-3B

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 5
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479319/326-20-50-5

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- Definition

The cash inflow from collection of repayments from borrowers on loans that are secured with real estate mortgages and are held with the intention to resell in the near future.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 230
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 21
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482740/230-10-45-21

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 230
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 16
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482740/230-10-45-16

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- Details

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Commercial Mortgage Loans, Subordinate Loans and Other Lending Assets, Net - Activity Relating to Loan Investment Portfolio (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023	Jun. 30, 2022	Jun. 30, 2021	Dec. 31, 2023
Principal Balance
Principal value, beginning balance	$ 8,384,575
Principal value, ending balance	8,318,448
Specific CECL Allowance
Specific provision for loan loss, beginning	(193,000)
Specific provision for loan loss, ending	(335,000)
Carry Value, Net
Increase in Specific CECL Allowance, net			$ 10,000	$ (20,000)
Valuation allowance, loan held for sale	0	$ (4,624)
General CECL allowance	(32,558)				$ (26,482)
Carrying value, net	8,285,890				$ 8,358,093
Off-balance-sheet, credit loss, liability, amount excluded	3,600
Commercial Mortgage and Subordinated Portfolio Segment
Principal Balance
Principal value, beginning balance	8,610,110
Add-on loan fundings	321,766
Loan repayments	(175,731)
Gain (loss) on foreign currency translation	(72,337)
Valuation allowance, loan held for sale	(679)
Amortization of fees	0
Principal value, ending balance	8,683,129
Deferred Fees/Other Items
Deferred fees/other items, beginning	(32,535)
Gain (loss) on foreign currency translation	289
Valuation allowance, loan held for sale	0
Deferred fees and other items	(4,936)
Amortization of fees	7,501
Deferred fees/other items, ending	(29,681)
Specific CECL Allowance
Specific provision for loan loss, beginning	(193,000)	(133,500)
Specific provision for loan loss, ending	(335,000)	$ (133,500)
Carry Value, Net
Carrying value, beginning balance	8,384,575
Add-on loan fundings	321,766
Loan repayments	(175,731)
Gain (loss) on foreign currency translation	(72,048)
Increase in Specific CECL Allowance, net	(142,000)
Valuation allowance, loan held for sale	(679)
Deferred fees and other items	(4,936)
Amortization of fees	7,501
Carrying value, ending balance	$ 8,318,448