Summary of Significant Accounting Policies (Details 3) (Series D)	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012
Series D
Shareholders' Equity
Preferred shares, dividend yield (as a percent)	6.50%	6.50%
Percentage of average closing market price of the entity's common stock based on which ratio for conversion of preferred shares into common shares is determined	98.00%