Previously Consolidated Variable Interest Entities (Details 10) (Previously Consolidated Variable Interest Entities, Non-performing loans, USD $) In Thousands, unless otherwise specified	Dec. 31, 2011
Principal Balance	$ 424,357
Net Book Value	87,854
Senior Mortgage Loans
Principal Balance	24,700
Net Book Value	11,638
Subordinated interests in mortgages
Principal Balance	111,776
Net Book Value	55,677
Mezzanine and Other Loans
Principal Balance	248,483
Net Book Value	$ 20,539

Reflects the carrying amount of loans deemed to be questionable as to collection on which no interest is continuing to be recognized.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 7

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=7512638&loc=d3e5111-111524

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher AICPA

-Name Statement of Position (SOP)

-Number 01-6

-Paragraph 13

-Subparagraph g

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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