Debt instrument extension period.

No definition available.

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- Definition

Debt Instrument, Number of Extensions Available

+ References

No definition available.

+ Details

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Period Type:	duration

- Definition

Line of Credit Covenant, Consolidated Recourse Indebtedness

+ References

No definition available.

+ Details

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

- Definition

Line of Credit, Covenant, Maximum Debt to Tangible Net Worth Ratio

+ References

No definition available.

+ Details

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Namespace Prefix:	ari_
Data Type:	xbrli:pureItemType
Balance Type:	na
Period Type:	duration

- Definition

Line of Credit Covenant, Minimum EBITDA to Interest Expense Ratio

+ References

No definition available.

+ Details

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Namespace Prefix:	ari_
Data Type:	xbrli:pureItemType
Balance Type:	na
Period Type:	duration

- Definition

Line of Credit Covenant, Minimum Liquidity

+ References

No definition available.

+ Details

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

- Definition

Line of Credit Covenant, Minimum Liquidity Percentage

+ References

No definition available.

+ Details

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Namespace Prefix:	ari_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Line of Credit, Covenant, Minimum Net Asset Value

+ References

No definition available.

+ Details

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

- Definition

Line of Credit, Covenant, Minimum Shareholder's Equity of Gross Capital Proceeds

+ References

No definition available.

+ Details

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Namespace Prefix:	ari_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Line of Credit Facility, Covenant Terms, Minimum Consolidated Tangible Net Worth Covenant, Amount

+ References

No definition available.

+ Details

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Balance Type:	credit
Period Type:	instant

- Definition

Line of Credit Facility, Covenant Terms, Minimum Consolidated Tangible Net Worth Covenant, Percentage of Additional Net Cash Proceeds

+ References

No definition available.

+ Details

Name:	ari_LineofCreditFacilityCovenantTermsMinimumConsolidatedTangibleNetWorthCovenantPercentageofAdditionalNetCashProceeds
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Balance Type:	na
Period Type:	duration

- Definition

Line of Credit Facility, Covenant Terms, Minimum Net Income During Four Consecutive Quarters

+ References

No definition available.

+ Details

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

- Definition

Line of Credit Facility, Covenant Terms, Total Recourse Indebtedness, Percent

+ References

No definition available.

+ Details

Name:	ari_LineofCreditFacilityCovenantTermsTotalRecourseIndebtednessPercent
Namespace Prefix:	ari_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Line of Credit Facility, Estimated Fair Value of Collateral Pledged Percentage

+ References

No definition available.

+ Details

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Namespace Prefix:	ari_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Line of Credit Facility, Margin of Cash Borrowed, Percentage

+ References

No definition available.

+ Details

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Namespace Prefix:	ari_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Line of Credit Facility, Period of Potential Extension

+ References

No definition available.

+ Details

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

- Definition

Line of Credit Facility, Threshold Amount for Margin Calls

+ References

No definition available.

+ Details

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

- Definition

Number of Subsidiaries, Covenant Terms

+ References

No definition available.

+ Details

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Namespace Prefix:	ari_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
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

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Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

+ Details

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Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.19(b),22(b))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

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

- Definition

The fee, expressed as a percentage of the line of credit facility, for available but unused credit capacity under the credit facility.

+ References

No definition available.

+ Details

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Period Type:	duration

- Definition

Amount, after the effects of master netting arrangements, of funds outstanding borrowed in the form of a security repurchase agreement between the entity and another party for the sale and repurchase of identical or substantially the same securities at a date certain for a specified price. Includes liabilities not subject to a master netting arrangement and not elected to be offset.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 20
-Section 50
-Paragraph 3
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=51824906&loc=SL20225862-175312

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08.(m)(1)(a)(i))
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.13(1))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 20
-Section 55
-Paragraph 10
-URI http://asc.fasb.org/extlink&oid=51825145&loc=SL20226008-175313

Reference 5: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 20
-Section 45
-Paragraph 11
-URI http://asc.fasb.org/extlink&oid=49176635&loc=d3e9760-107771

Reference 6: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Repurchase Agreement Accounted for as a Collateralized Borrowing
-URI http://asc.fasb.org/extlink&oid=49203159

+ Details

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Borrowings - Additional Information (Details)			1 Months Ended			12 Months Ended
Borrowings - Additional Information (Details)	Sep. 29, 2016 USD ($) extension	Jan. 26, 2015 USD ($)	Apr. 30, 2014 USD ($)	Sep. 30, 2013 USD ($)	Jan. 31, 2010 subsidiary	Dec. 31, 2016 USD ($)	Dec. 31, 2015 USD ($)
Debt Instrument [Line Items]
Borrowings under repurchase agreements						$ 1,139,803,000	$ 918,421,000
Line of Credit [Member]
Debt Instrument [Line Items]
Borrowings under repurchase agreements						$ 1,139,803,000	$ 918,421,000
Line of Credit [Member] \| London Interbank Offered Rate (LIBOR) [Member]
Debt Instrument [Line Items]
Basis spread on interest rate						0.77%	0.43%
Line of Credit [Member] \| JP Morgan Chase [Member]
Debt Instrument [Line Items]
Maximum borrowing under facility						$ 943,000,000	$ 600,000,000
Borrowings under repurchase agreements						657,452,000	445,942,000
Line of Credit [Member] \| Deutsche Bank Repurchase Facility [Member]
Debt Instrument [Line Items]
Maximum borrowing under facility	$ 300,000,000					300,000,000
Extension option	1 year
Borrowings under repurchase agreements						137,355,000
Debt instrument, number of extension available \| extension	2
Line of Credit [Member] \| UBS [Member]
Debt Instrument [Line Items]
Borrowings under repurchase agreements						133,899,000	133,899,000
Line of Credit [Member] \| Deutsche Bank [Member]
Debt Instrument [Line Items]
Borrowings under repurchase agreements						177,203,000	300,005,000
Line of Credit [Member] \| Goldman Sachs [Member]
Debt Instrument [Line Items]
Borrowings under repurchase agreements						$ 40,657,000	$ 45,928,000
Line of Credit [Member] \| Goldman Sachs [Member] \| London Interbank Offered Rate (LIBOR) [Member]
Debt Instrument [Line Items]
Basis spread on interest rate						3.50%	3.50%
Line of Credit [Member] \| Minimum [Member] \| JP Morgan Chase [Member] \| London Interbank Offered Rate (LIBOR) [Member]
Debt Instrument [Line Items]
Basis spread on interest rate						2.25%	2.25%
Line of Credit [Member] \| Minimum [Member] \| Deutsche Bank Repurchase Facility [Member] \| London Interbank Offered Rate (LIBOR) [Member]
Debt Instrument [Line Items]
Basis spread on interest rate						2.66%
JP Morgan Facility [Member] \| Line of Credit [Member] \| JP Morgan Chase [Member]
Debt Instrument [Line Items]
Number of subsidiaries \| subsidiary					2
Amended and Restated JPMorgan Facility [Member] \| Line of Credit [Member] \| JP Morgan Chase [Member]
Debt Instrument [Line Items]
Maximum borrowing under facility						$ 943,000,000
Term of debt instrument						3 years
Extension option						1 year
Threshold amount for margin calls						$ 250,000
Covenant terms, minimum net asset value						$ 750,000,000
Covenant terms, minimum consolidated tangible net worth, additional percentage of net cash proceeds						75.00%
Covenant terms, maximum debt to tangible net worth ratio						3
Covenant terms, minimum liquidity percentage						5.00%
Covenant terms, consolidated recourse indebtedness						$ 15,000,000
Amended and Restated JPMorgan Facility [Member] \| Line of Credit [Member] \| Minimum [Member] \| JP Morgan Chase [Member]
Debt Instrument [Line Items]
Estimated fair value of collateral pledged, percentage						25.00%
Amended and Restated JPMorgan Facility [Member] \| Line of Credit [Member] \| Minimum [Member] \| JP Morgan Chase [Member] \| London Interbank Offered Rate (LIBOR) [Member]
Debt Instrument [Line Items]
Basis spread on interest rate						2.25%
Amended and Restated JPMorgan Facility [Member] \| Line of Credit [Member] \| Maximum [Member] \| JP Morgan Chase [Member]
Debt Instrument [Line Items]
Estimated fair value of collateral pledged, percentage						80.00%
Amended and Restated JPMorgan Facility [Member] \| Line of Credit [Member] \| Maximum [Member] \| JP Morgan Chase [Member] \| London Interbank Offered Rate (LIBOR) [Member]
Debt Instrument [Line Items]
Basis spread on interest rate						4.75%
Repurchase Facility [Member] \| Line of Credit [Member] \| JP Morgan Chase [Member]
Debt Instrument [Line Items]
Maximum borrowing under facility						$ 800,000
Asset Specific Financing [Member] \| Line of Credit [Member] \| JP Morgan Chase [Member]
Debt Instrument [Line Items]
Maximum borrowing under facility						$ 143,000
DB Facility [Member] \| Line of Credit [Member] \| Deutsche Bank [Member]
Debt Instrument [Line Items]
Covenant terms, minimum shareholder's equity of gross capital proceeds			50.00%
DB Facility [Member] \| Line of Credit [Member] \| Deutsche Bank [Member] \| Three Month LIBOR [Member]
Debt Instrument [Line Items]
Maximum borrowing under facility			$ 300,000
DB Facility [Member] \| Line of Credit [Member] \| Minimum [Member] \| Deutsche Bank [Member] \| Three Month LIBOR [Member]
Debt Instrument [Line Items]
Basis spread on interest rate			1.80%
DB Facility [Member] \| Line of Credit [Member] \| Maximum [Member] \| Deutsche Bank [Member] \| Three Month LIBOR [Member]
Debt Instrument [Line Items]
Basis spread on interest rate			2.32%
Undrawn non-use fee percentage			1.80%
Goldman Facility [Member] \| Line of Credit [Member] \| Goldman Sachs [Member]
Debt Instrument [Line Items]
Maximum borrowing under facility		$ 52,524,000
Covenant terms, maximum debt to tangible net worth ratio		3
Covenant terms, minimum consolidated tangible net worth		$ 750,000
Covenant terms, minimum liquidity		$ 15,000
Covenant terms, total recourse indebtedness, percent		5.00%
Covenant terms, minimum EBITDA to interest expense ratio		1.5
Covenant terms, minimum net income		$ 1
Goldman Facility [Member] \| Line of Credit [Member] \| Goldman Sachs [Member] \| London Interbank Offered Rate (LIBOR) [Member]
Debt Instrument [Line Items]
Basis spread on interest rate		3.50%
UBS Facility [Member] \| Line of Credit [Member] \| UBS [Member]
Debt Instrument [Line Items]
Maximum borrowing under facility				$ 133,899,000
Estimated fair value of collateral pledged, percentage				100.00%
Covenant terms, minimum net asset value				$ 500,000,000
Covenant terms, maximum debt to tangible net worth ratio				3
Length of potential extension				1 year
Margin of cash borrowed, percentage				22.50%
UBS Facility [Member] \| Line of Credit [Member] \| UBS [Member] \| Six Month LIBOR [Member]
Debt Instrument [Line Items]
Basis spread on interest rate				1.55%