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Represents the amount of weighted average daily rate of properties classified as real estate owned.

No definition available.

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Represents the weighted average occupancy rate of properties classified as real estate owned.

No definition available.

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Data Type:	num:percentItemType
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Represents the amount of weighted average revenue per available room of properties classified as real estate owned.

No definition available.

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Data Type:	xbrli:monetaryItemType
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The charge against earnings in the period to reduce the carrying amount of real property to fair value.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 360
-SubTopic 10
-Section 50
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The cumulative amount of depreciation for real estate property held for investment purposes.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
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Amount of real estate investment property which may include the following: (1) land available-for-sale; (2) land available-for-development; (3) investments in building and building improvements; (4) tenant allowances; (5) developments in-process; (6) rental properties; and (7) other real estate investments.

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Amount of real estate investment property, net of accumulated depreciation, which may include the following: (1) land available-for-sale; (2) land available-for-development; (3) investments in building and building improvements; (4) tenant allowances; (5) developments in-process; (6) rental properties; and (7) other real estate investments.

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Amount of cash and cash equivalents restricted as to withdrawal or usage. Cash includes, but is not limited to, currency on hand, demand deposits with banks or financial institutions, and other accounts with general characteristics of demand deposits. Cash equivalents include, but are not limited to, short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Name:	us-gaap_MortgageLoansOnRealEstateDescriptionTypeOfPropertyAxis=us-gaap_HotelMember
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Data Type:	na
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Period Type:

Name:	us-gaap_MortgageLoansOnRealEstateDescriptionTypeOfPropertyAxis=us-gaap_OfficeBuildingMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Name:	abr_MortgageLoansOnRealEstateSubTypeOfPropertyAxis=us-gaap_LandAndLandImprovementsMember
Namespace Prefix:
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