Fair Value (Details 3) (USD $)	Mar. 31, 2013 creditfacility	Dec. 31, 2012
Financial assets:
Real estate debt investments, net	$ 624,377,000	$ 514,058,000
Investments in and advances to unconsolidated ventures	112,280,000
Real estate securities, available for sale	53,999,000	29,582,000
Financial liabilities:
Securitization bonds payable	124,559,000	124,491,000
Credit facilities	180,371,000	126,321,000
Credit Facilities
Number of term credit facilities under which amounts are outstanding	5
Principal Amount
Financial assets:
Real estate debt investments, net	623,684,000	513,833,000
Investments in and advances to unconsolidated ventures	112,280,000
Real estate securities, available for sale	104,542,000	30,575,000
Future funding commitments related to real estate debt investments	25,900,000
Financial liabilities:
Securitization bonds payable	124,659,000	124,659,000
Credit facilities	180,371,000	126,321,000
Carrying Value
Financial assets:
Real estate debt investments, net	624,377,000	514,058,000
Investments in and advances to unconsolidated ventures	112,280,000
Real estate securities, available for sale	53,999,000	29,582,000
Financial liabilities:
Securitization bonds payable	124,559,000	124,491,000
Credit facilities	180,371,000	126,321,000
Fair Value
Financial assets:
Real estate debt investments, net	623,684,000	513,833,000
Investments in and advances to unconsolidated ventures	112,280,000
Real estate securities, available for sale	53,999,000	29,582,000
Financial liabilities:
Securitization bonds payable	124,892,000	124,862,000
Credit facilities	$ 180,371,000	$ 126,321,000

Represents the number of term credit facilities under which amounts are outstanding.

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Represents the amount of the entity's total future funding commitments, which are subject to certain conditions that borrowers must meet to qualify for such fundings.

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No definition available.

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Represents the carrying value, as of the balance sheet date, of bonds payable, which are secured by commercial mortgage loans.

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Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

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- Definition

Total investments in (A) an entity in which the entity has significant influence, but does not have control, (B) subsidiaries that are not required to be consolidated and are accounted for using the equity and or cost method, and (C) an entity in which the reporting entity shares control of the entity with another party or group. Includes long-term advances receivable from a party that is affiliated with the reporting entity by means of direct or indirect ownership.

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The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

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The balance represents the amount of loans that are secured by real estate mortgages, offset by the reserve to cover probable credit losses on the loan portfolio.

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