Fair Value (Details) (USD $) In Thousands, unless otherwise specified	Jun. 30, 2013	Dec. 31, 2012
Financial assets accounted for at fair value on a recurring basis by level within fair value hierarchy
Investments in private equity funds	$ 111,093
Real estate securities, available for sale	55,289	29,582
Financial assets measured at non-recurring basis	0	0
Financial liabilities measured at non-recurring basis	0	0
Recurring basis \| Level 1
Financial assets accounted for at fair value on a recurring basis by level within fair value hierarchy
Investments in private equity funds	7,500
Recurring basis \| Level 2
Financial assets accounted for at fair value on a recurring basis by level within fair value hierarchy
Real estate securities, available for sale	55,289	29,582
Recurring basis \| Level 3
Financial assets accounted for at fair value on a recurring basis by level within fair value hierarchy
Investments in private equity funds	111,093
Recurring basis \| Total
Financial assets accounted for at fair value on a recurring basis by level within fair value hierarchy
Investments in private equity funds	118,593
Real estate securities, available for sale	$ 55,289	$ 29,582

This element represents the aggregate of the assets reported on the balance sheet at period end measured at fair value on a nonrecurring basis by the entity. This element is intended to be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements.

No definition available.

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 25

-Paragraph 1

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=28360136&loc=d3e22054-111558

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 50

-Paragraph 5

-Subparagraph (aa)

-URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27232-111563

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 45

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6871852&loc=d3e26610-111562

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- Definition

Fair value portion of investments in an entity not consolidated. Includes, but is not limited to, investments in an entity that is affiliated with the reporting entity by means of direct or indirect ownership, an entity in which the reporting entity shares control of the entity with another party or group, an entity which the company has significant influence, but does not have control and subsidiaries that are not required to be consolidated and are accounted for using the equity or cost method.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 820

-SubTopic 10

-Section 50

-Paragraph 1

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=25499696&loc=d3e19190-110258

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- Definition

Aggregation of the liabilities reported on the balance sheet measured at fair value on a nonrecurring basis by the entity.

+ References

No definition available.

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