Consolidated Statements of Beneficiaries' Equity (Unaudited) (Parenthetical) (USD $)	6 Months Ended
Jun. 30, 2011	Jun. 30, 2010
Distributions declared, per share	$ 0.30	$ 0.30
Cumulative Distributions
Distributions declared, per share	$ 0.30	$ 0.30
Non-Controlling Interests
Distributions declared, per share	$ 0.30	$ 0.30

Aggregate dividends declared during the period for each share of common stock outstanding.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 04
-Article 3

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