Consolidated Balance Sheets (Parenthetical) (USD $)	Sep. 30, 2011	Dec. 31, 2010
Common stock, par value	$ 0.01	$ 0.01
Common stock, shares authorized	100,000,000	100,000,000
Common stock, shares issued	39,240,264	30,972,353
Common stock, shares outstanding	39,240,264	30,972,353
8.034% Series A Cumulative Redeemable Perpetual Preferred Stock
Cumulative Redeemable Preferred Stock, par value per share	$ 0.01	$ 0.01
Cumulative Redeemable Preferred Stock, shares authorized	10,000,000	10,000,000
Cumulative Redeemable Preferred Stock, shares issued	8,000,000	0
Cumulative Redeemable Preferred Stock, shares outstanding	8,000,000	0
Series B Subordinated Non-Voting Cumulative Redeemable Preferred Stock
Cumulative Redeemable Preferred Stock, par value per share	$ 0.01	$ 0.01
Cumulative Redeemable Preferred Stock, shares authorized	1,740,000	0
Cumulative Redeemable Preferred Stock, shares issued	1,242,462	0
Cumulative Redeemable Preferred Stock, shares outstanding	1,242,462	0