Net Investments in Properties (Details 1) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2012	Dec. 31, 2011
Real Estate Investment Property At Cost
Accumulated depreciation (inclusive of amounts attributable to consolidated VIEs of $16,110 and $22,350, respectively)	$ (136,068)	$ (135,175)
Net investments in properties	2,295,248	621,182
Real Estate
Real Estate Investment Property At Cost
Land	509,530	111,483
Buildings	1,822,083	534,999
Accumulated depreciation (inclusive of amounts attributable to consolidated VIEs of $16,110 and $22,350, respectively)	(116,075)	(118,054)
Net investments in properties	2,215,538	528,428
Operating real estate
Real Estate Investment Property At Cost
Land	22,158	24,031
Buildings	77,545	85,844
Accumulated depreciation (inclusive of amounts attributable to consolidated VIEs of $16,110 and $22,350, respectively)	(19,993)	(17,121)
Net investments in properties	$ 79,710	$ 92,754

Aggregate of the carrying amounts as of the balance sheet date of investments in building and building improvements.

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- Definition

Carrying amount as of the balance sheet date of real estate held for productive use. This excludes land held for sale.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section 45

-Paragraph 4

-Subparagraph (e)

-URI http://asc.fasb.org/extlink&oid=6361293&loc=d3e6812-107765

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.13)

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

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- Definition

The cumulative amount of depreciation for real estate property held for investment purposes.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 944

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.7-03.1(3))

-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 1

-Article 7

+ Details

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- Definition

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.

+ References

+ Details

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