Consolidated Balance Sheets (Parenthetical) (USD $) In Thousands, except Share data	Jun. 30, 2011	Dec. 31, 2010
ASSETS
Allowance for doubtful accounts	$ 27	$ 13
Shareholders' equity:
Preferred shares of beneficial interest, liquidation preference	$ 25	$ 25
Preferred shares of beneficial interest, par value	$ 0.01	$ 0.01
Preferred shares of beneficial interest, shares authorized	100,000,000	100,000,000
Preferred shares of beneficial interest, shares issued	5,000,000	5,000,000
Preferred shares of beneficial interest, shares outstanding	0	0
Common shares of beneficial interest, par value	$ 0.01	$ 0.01
Common shares of beneficial interest, shares authorized	500,000,000	500,000,000
Common shares of beneficial interest, shares issued	50,771,380	39,814,760
Common shares of beneficial interest, shares outstanding	50,771,380	39,814,760