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Represents information pertaining to the percentage of indirect ownership in a business.

No definition available.

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Represents information pertaining to the percentage of noncontrolling interest in equity method investment.

No definition available.

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Represents the number of equity affiliates formed.

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Cost basis for investment of equity participation interest.

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Represents expenses related to the distribution from the equity investments.

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The period of time over which the litigation settlement will be paid.

No definition available.

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The cash outflow associated with the purchase of or advances to equity method investments by the company, along with a consortium of independent outside investors.

No definition available.

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Represents period of each extension option available.

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Represents the percentage of equity participation redeemed.

No definition available.

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Represents the percentage of ownership of common stock or equity participation owned by related party in the entity.

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

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Amount of distribution received from equity method investee for return on investment, classified as operating activities. Excludes distribution for return of investment, classified as investing activities.

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The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

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This item represents the carrying amount on the entity's balance sheet of its investment in common stock of an equity method investee. This is not an indicator of the fair value of the investment, rather it is the initial cost adjusted for the entity's share of earnings and losses of the investee, adjusted for any distributions (dividends) and other than temporary impairment (OTTI) losses recognized.

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This item represents the entity's proportionate share for the period of the net income (loss) of its investee (such as unconsolidated subsidiaries and joint ventures) to which the equity method of accounting is applied. This item includes income or expense related to stock-based compensation based on the investor's grant of stock to employees of an equity method investee.

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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.

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Amount of litigation expense, including but not limited to legal, forensic, accounting, and investigative fees.

No definition available.

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The carrying amount of the outstanding balance due under the mortgage loan.

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The number of real estate properties owned as of the balance sheet date.

No definition available.

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The cash outflow associated with the purchase of or advances to an equity method investments, which are investments in joint ventures and entities in which the entity has an equity ownership interest normally of 20 to 50 percent and exercises significant influence.

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Carrying value as of the balance sheet date, including the current and noncurrent portions, of collateralized debt obligations (with maturities initially due after one year or beyond the operating cycle, if longer). Such obligations include mortgage loans, chattel loans, and any other borrowings secured by assets of the borrower.

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Name:	us-gaap_MortgageLoansOnRealEstateLoanTypeAxis=abr_ResidentialMortgageBankingCompanyAcquisitionsMember
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Name:	us-gaap_RelatedPartyTransactionsByRelatedPartyAxis=abr_ArborCommercialMortgageLLCMember
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Name:	us-gaap_MortgageLoansOnRealEstateLoanTypeAxis=abr_NonQualifiedResidentialMortgageMember
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Name:	us-gaap_RangeAxis=us-gaap_MaximumMember
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Name:	invest_InvestmentAxis=abr_JTPrimeMember
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