Consolidated Statements of Changes in Stockholders' Equity (Parenthetical) (USD $) In Thousands, except Share data, unless otherwise specified	12 Months Ended
	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Consolidated Statements of Changes in Stockholders' Equity (Parenthetical) [Abstract]
Common shares issued (in shares)		458,342
Offering expenses related to issuance of common shares		$ 78,912
Number of preferred shares converted to common shares (in shares)	7,750	10,550
Number of common shares issued upon conversion of preferred stock (in shares)	128,738	175,249
Number of Series A Convertible Preferred Stock (Net) (in shares)			18,300
Number of restricted stock (in shares)	1,000		6,000
Number of Forfeiture of restricted stock (in shares)	625