Real Estate Real Estate (Summary Of Real Estate Investments) (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2011	Dec. 31, 2010
Real Estate Investments [Line Items]
Cost	$ 4,434,544	$ 3,895,942
Accumulated Depreciation and Amortization	(1,127,588)	(1,035,204)
Encumbrances	810,616	589,441
Retail And Mixed-Use Properties [Member]
Real Estate Investments [Line Items]
Cost	4,312,189	3,779,203
Accumulated Depreciation and Amortization	(1,087,704)	(999,209)
Encumbrances	724,287	505,934
Retail Properties Under Capital Leases [Member]
Real Estate Investments [Line Items]
Cost	113,605	108,381
Accumulated Depreciation and Amortization	(33,019)	(29,421)
Encumbrances	63,093	59,940
Residential [Member]
Real Estate Investments [Line Items]
Cost	8,750	8,358
Accumulated Depreciation and Amortization	(6,865)	(6,574)
Encumbrances	$ 23,236	$ 23,567

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The amount of a lien or mortgage outstanding as of the balance sheet date on a specific property.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 970

-SubTopic 360

-Section S99

-Paragraph 1

-Subparagraph (SX 210.12-28)

-URI http://asc.fasb.org/extlink&oid=6590653&loc=d3e638233-123024

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 04

-Paragraph c

-Subparagraph Schedule III

-Article 5

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 28

-Article 12

Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 205

-SubTopic 10

-Section S99

-Paragraph 6

-Subparagraph (SX 210.5-04.(c) Schedule III)

-URI http://asc.fasb.org/extlink&oid=6882300&loc=d3e5864-122674

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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 SEC

-Name Regulation S-X (SX)

-Number 210

-Article 7

-Section 03

-Paragraph 1

Reference 2: 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

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- Definition

Represents a total 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

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(d))

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

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