Mortgage Loans on Real Estate, Funded Amount of Mortgages

No definition available.

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

- 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=6589523&loc=d3e617274-123014

+ Details

Name:	srt_MortgageLoansOnRealEstateFaceAmountOfMortgages
Namespace Prefix:	srt_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

The cash inflow from repayments of the balance excluding interest (principal) on loans receivable and leases held for investment purposes.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 12
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3179-108585

+ Details

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

- Definition

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.

+ References

No definition available.

+ Details

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Period Type:	duration

- Details

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- Details

Name:	us-gaap_FinancingReceivablePortfolioSegmentAxis=ari_CommercialMortgagePortfolioSegmentMember
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- Details

Name:	us-gaap_FinancingReceivablePortfolioSegmentAxis=ari_SubordinateMortgagePortfolioSegmentMember
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Subsequent Events (Details) - USD ($) $ in Millions	2 Months Ended
Subsequent Events (Details) - USD ($) $ in Millions	Feb. 14, 2019	Dec. 31, 2018
Subsequent Event [Member]
Subsequent Event [Line Items]
Proceeds from loan repayments	$ 213.9
Commercial Mortgage Portfolio Segment [Member]
Subsequent Event [Line Items]
Funded amount of mortgages		$ 65.2
Commercial Mortgage Portfolio Segment [Member] \| Subsequent Event [Member]
Subsequent Event [Line Items]
Original face amount	203.8
Funded amount of mortgages	197.0
Subordinate Mortgage Portfolio Segment [Member] \| Subsequent Event [Member]
Subsequent Event [Line Items]
Original face amount	$ 228.0