CONDENSED CONSOLIDATED BALANCE SHEETS (Parenthetical) - $ / shares	Sep. 30, 2015	Dec. 31, 2014
Schedule of Stockholders' Equity [Line Items]
Preferred stock, par value	$ 100	$ 100
Preferred stock, shares authorized	100,000	100,000
Preferred stock, redemption value per share (in dollars per share)	$ 10,000	$ 10,000
Common stock, par value	$ 0.01	$ 0.01
Common stock, shares authorized	228,000,000
Common stock, shares issued	73,297,205	71,568,936
Treasury stock, shares	455,689	262,070
Series A Preferred Stock
Schedule of Stockholders' Equity [Line Items]
Preferred stock, issued	7,070	7,945
Series B Preferred Stock
Schedule of Stockholders' Equity [Line Items]
Preferred stock, issued	32,500	32,500