Condensed Consolidated Balance Sheets [Parenthetical] (USD $)	Mar. 31, 2014	Dec. 31, 2013
Preferred stock, shares authorized	7,000,000	7,000,000
Preferred stock, shares issued	0	0
Preferred stock, shares outstanding	0	0
Common stock, par value (in dollars per share)	$ 0.01	$ 0.01
Common stock, shares authorized	150,000,000	150,000,000
Common stock, shares outstanding	86,688,613	77,886,031