Equity, Capital and Other Interests Preferred (Details) (USD $)	3 Months Ended	12 Months Ended
Mar. 31, 2015	Mar. 31, 2014	Dec. 31, 2014
Class of Stock [Line Items]
Preferred Shares of beneficial interest, $0.01 par value; 100,000,000 shares authorized; 803,600 shares issued and outstanding as of March 31, 2015 and 1,000,000 shares issued and outstanding as of December 31, 2014	$ 40,180,000us-gaap_PreferredStockValueOutstanding		$ 50,000,000us-gaap_PreferredStockValueOutstanding
Partial redemption of 8.29% Series K Cumulative Redeemable	9,820,000	0
Redemption Premium	2,789,000us-gaap_RedemptionPremium	0us-gaap_RedemptionPremium
OPERATING PARTNERSHIP
Class of Stock [Line Items]
Partial redemption of 8.29% Series K Cumulative Redeemable	9,820,000	0
Redemption Premium	(2,789,000)	0
Preferred Units	40,180,000		50,000,000
Series K Preferred Stock [Member]
Class of Stock [Line Items]
Preferred Stock Preference Units Dividend Rate Percentage	8.29%		8.29%
Preferred Stock Preference Units Redemption Price Per Share Unit	$ 50.00		$ 50.00
Preferred Stock Preference Units Issued	803,600		1,000,000
Preferred Stock Preference Units Outstanding	803,600		1,000,000
Preferred Stocks Preference Units Redemption Date	Dec. 10, 2026
Annual Dividend Per Preferred Share Preference Unit	$ 4.145
Preferred Shares of beneficial interest, $0.01 par value; 100,000,000 shares authorized; 803,600 shares issued and outstanding as of March 31, 2015 and 1,000,000 shares issued and outstanding as of December 31, 2014	40,180,000		50,000,000
Preferred Stock Preference Units Repurchased and Retired	196,400
Partial redemption of 8.29% Series K Cumulative Redeemable	9,820,000
Payments For Repurchase Of Preference Units	12,700,000
Redemption Premium	2,789,000
Series K Preferred Stock [Member] \| OPERATING PARTNERSHIP
Class of Stock [Line Items]
Preferred Stock Preference Units Dividend Rate Percentage	8.29%		8.29%
Preferred Stock Preference Units Redemption Price Per Share Unit	$ 50.00		$ 50.00
Preferred Stock Preference Units Issued	803,600		1,000,000
Preferred Stock Preference Units Outstanding	803,600		1,000,000
Preferred Stocks Preference Units Redemption Date	Dec. 10, 2026
Annual Dividend Per Preferred Share Preference Unit	$ 4.145
Preferred Units	$ 40,180,000		$ 50,000,000

Aggregate dividends payable during the year for each share/unit of preferred stock/preference units outstanding.

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The percentage rate used to calculate dividend payments on preferred shares/preference units.

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No definition available.

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Total number of preferred shares/preference units issued to security holders. May be all or portion of the number of preferred shares/preference units authorized. Excludes preferred shares/preference units that are classified as debt.

+ References

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Aggregate number of preferred shares/preference units held by security holders. Does not include preferred shares/preference units that have been repurchased.

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The price per share/unit at which the preferred share/preference units of the entity has priority over common shares/units in the distribution of dividends and in the event of liquidation of the entity is redeemed or may be called at. The redemption features of these preferred shares/units are solely within the control of the issuer.

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The date at which or after redeemable preferred stock/preference units may be redeemed for cash at the option of the company in whole or in part at a redemption price equal to the liquidation price per share/units plus accrued and unpaid distributions if any.

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No definition available.

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Value of all nonredeemable preferred stock (or preferred stock redeemable solely at the option of the issuer) held by shareholders, which is net of related treasury stock. May be all or a portion of the number of preferred shares authorized. These shares represent the ownership interest of the preferred shareholders.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.28)

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-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 29

-Article 5

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- Definition

The amount of the preferred partners' ownership interests.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 272

-SubTopic 10

-Section 50

-Paragraph 1

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-Publisher SEC

-Name Staff Accounting Bulletin (SAB)

-Number Topic 4

-Section F

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The excess of the (1) fair value of consideration transferred to the holders of a security in excess of (2) the carrying amount of the security reported on the registrant's balance sheet, which will be deducted from net earnings to derive net earnings available to common shareholders. This amount is generally an adjustment considered in the computation of earnings per share.

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Amount of decrease of par value, additional paid in capital (APIC) and retained earnings of common and preferred stock retired from treasury when treasury stock is accounted for under the par value method.

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Number of shares of common and preferred stock retired from treasury during the period.

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Equity impact of the cost of common and preferred stock that were repurchased during the period. Recorded using the par value method.

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 04

-Article 3

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

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