Noncontrolling Interests (Operating Partnership Of Preferred Units Outstanding) (Details) (USD $) In Thousands, except Share data	6 Months Ended
Jun. 30, 2011	Dec. 31, 2010
Units Outstanding	223,300	2,136,700
Amount	$ 5,583	$ 53,418
Series J [Member]
Issuance Date	May & June, 2004
Dividend Rate	7.500%
Units Outstanding		1,710,000
Amount		42,750
Series N [Member]
Issuance Date	December, 2005
Earliest Potential Redemption Date	Dec. 01, 2010
Dividend Rate	7.125%
Units Outstanding	223,300	223,300
Amount	5,583	5,583
Series Q [Member]
Issuance Date	March, 2007
Dividend Rate	6.550%
Units Outstanding		203,400
Amount		$ 5,085

Preferred Equity Issuance Date.

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- Definition

Carrying amount of the equity interests owned by noncontrolling preferred unit holders in an entity included in the reporting entity's consolidated financial statements.

+ Details

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- Definition

Dividend payment percentage rate or fixed dollar amount per share, such as three percent or $2.67 per share.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 129
-Paragraph 2, 3, 4, 5, 6, 7, 8

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher AICPA
-Name Accounting Principles Board Opinion (APB)
-Number 12
-Paragraph 10

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 04
-Article 3

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 02
-Paragraph 29
-Article 5

+ Details

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- Definition

The date upon which capital stock of an entity that has priority over common stock in the distribution of dividends and in the event of liquidation of the entity is redeemed. The redemption features of this capital stock are solely within the control of the issuer.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 129
-Paragraph 4, 8

+ Details

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- Definition

The number of preferred units outstanding. Preferred partners are partners in a publicly listed limited partnership or master limited partnership with preferential rights and privileges.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Staff Accounting Bulletin (SAB)
-Number Topic 4
-Section F

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Emerging Issues Task Force (EITF)
-Number 87-21

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher AICPA
-Name Practice Bulletin (PB)
-Number 14
-Paragraph 8, 10, 15

+ Details

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